ObservatoryUniversity of HelsinkiAnnual Report 2009

Observatory P.O. Box 14, FI-00014 University of Helsinki, Finlandhttp://www.astro.helsinki.fi/

ForewordThere is no need to repeat the contents of my foreword in theprevious annual report dated June 6th, 2009. From a profes-sional point of view, I find nothing good to write about therest this year. The following lines

Anger may in time change to gladness;vexation may be succeeded by content.But a kingdom that has once been destroyed can nevercome again into being;nor can the dead ever be brought back to life.

There is a wisdom which tells:When to go and when to return.What is to be done and what is to be left undone.What is fear and what is courage.What is bondage and what is liberation.This is pure wisdom.

are quotations from two completely different kinds of books.Now it is a good time to read those books again.

Lauri JetsuDirector of the ObservatoryHelsinki, December 22nd, 2009

Contents1 Interstellar medium, star formation and magnetic activity of stars 3

1.1 Research activities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31.2 Progress and highlights of scientific results in 2009 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

1.2.1 Magnetic activity in stars and circumstellar discs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31.2.2 Interstellar clouds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41.2.3 Prestellar cores and star formation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61.2.4 The Planck and Herschel satellite projects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61.2.5 Extragalactic Background Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

1.3 External financing and resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91.4 Tests of learning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91.5 Visits abroad . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101.6 Papers read at scientific conferences, symposia, meetings etc. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111.7 Visiting academics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111.8 Membership in scientific and scholarly societies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121.9 Other activities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121.10 Refereeing and Other Publishing Activities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

2 High Energy Astrophysics 132.1 General approach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132.2 Science topics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

2.2.1 The solar corona . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132.2.2 Clusters of galaxies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

2.3 Development of data analysis software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142.4 External financing and resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152.5 Tests of learning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152.6 Visits abroad . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152.7 Membership in scientific and scholarly societies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

3 Planetary System Research 193.1 Research activities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193.2 External financing and resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213.3 Tests of learning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213.4 Visits abroad . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213.5 Papers read at scientific conferences, symposia, meetings etc. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 223.6 Visiting academics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 233.7 Membership in scientific and scholarly societies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 233.8 Refereeing and Other Publishing Activities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

4 Lectures in 2009 25

5 Library 265.1 Library Merger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 265.2 LISA VI Conference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 265.3 Membership in scientific and scholarly societies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

6 Observatory Board 2007–2009 27

7 Publications 287.1 Articles in refereed journals (B1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 287.2 Papers in conference publications and compilations (B2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

8 Academic degrees 1995–2009 31

1 Interstellar medium, star formationand magnetic activity of starsStaff with a Ph.D. Thomas Hackman, Ph.D.

Lauri Haikala, DocentJorma Harju, DocentMika Juvela, DocentMaarit Korpi, DocentPetri Kapyla, Ph.D.Kimmo Lehtinen, DocentKalevi Mattila, Prof.Ilkka Tuominen, Prof.emer.Nathalie Ysard, Ph.D.

Ph.D. students Anne Liljestrom, M.ScMarjaana Lindborg, M. ScTuomas Lunttila, M.Sc.Johanna Malinen, M.Sc.Minja Makela, M.Sc.Oskari Miettinen, M.Sc.Marianna Ridderstad, M.Sc.Kyosti Ryynanen, M.Sc.Olli Sipila, M.Sc.Jan Snellman, M.Sc.

Associated scientists Axel Brandenburg, Ph.D., Prof.(Nordita, Stockholm, Sweden),

Thorsten Carroll, Ph.D.(Astroph. Inst. Potsdam, Germany)

Stephan Hotzel, Ph.D.(Cologne, Germany)

Ilya Ilyin, Ph.D.(Astroph. Inst. Potsdam, Germany),

Peter Johansson, Ph.D.(University Observatory, Munich)

Oleg Kochukhov, Ph. D.Uppsala University, Sweden),

Heidi Korhonen, Ph.D.(ESO, Garching, Germany)

Veli-Matti Pelkonen, PhD.(IPAC, Pasadena)

Jaan Pelt, Ph.D.(Tartu Observatory, Estonia)Peter Petrov, Ph.D.

(Crimean Astroph. Obs., Ukraine),Nikolai Piskunov, Ph.D., Prof.

(Uppsala University, Sweden),Mark Rawlings, Ph.D.

(Joint ALMA office, Santiago, Chile)Petri Vaisanen, Ph.D.

(SALT, South Africa)Nadezhda Zolotova, Ph.D.

Saint-Petersburg State Univ., Russia

1.1 Research activitiesThe activities of the research group are directed to the fol-lowing fields: (1) the formation of protostars in dense molec-ular cloud cores; (2) the properties and evolution of dust andmolecular gas in interstellar clouds; (3) radiative transfer andmagnetohydrodynamic (MHD) modelling of interstellar cloudsand protostellar accretion discs; (4) MHD-modelling of solarand active late-type star convection and turbulent dynamosand related optical spectropolarimetric observations using in-version methods; (5) the optical and infrared extragalacticbackground radiation.

The group uses ground-based and space-borne optical /infrared, (sub)millimetre, and radio telescopes. The stud-ies often are conducted in collaboration with research groupsfrom other countries. In recent years the ESO facilities havebeen of growing importance. The group has successfullyperformed several ESO/VLT observing programs and spe-

cial attention is paid to the 12-m Atacama Pathfinder Ex-periment (APEX) and to the Atacama Large Millimetre Ar-ray (ALMA). APEX became publicly available in 2006 andALMA will start its operation in 2010. The group has beenwell informed about available ESO telescopes and facilities:Mattila has been Finland’s representative in the ESO Councilsince 2004. Haikala has been (after Tuominen) Finland’s rep-resentative in the Scientific Technical Committee since 2007.Harju was since 2004 a member of the ALMA European Sci-entific Advisory Committee and, from the beginning of Febru-ary 2009, Haikala has acted as the Finnish representative. Ju-vela has served as a member and Harju as an Expert Advisorin the ESO Observing Programmes Committee.

During the past several years ESA’s Infrared Space Ob-servatory (ISO) has been important for the group. The ex-ploitation of the ISO data has continued intensively, often incombination with near-IR and (sub)mm data from ESO andother ground based telescopes such as the Australian Tele-scope Compact Array, the Effelsberg 100-m and the Onsala20-m radiotelescopes, and the 2.5-m Nordic Optical Tele-scope.

Based on its ISO experience, the group has been par-ticipating in the relevant Planck Surveyor science projects.Among the other future ESA missions the group is particu-larly well-prepared to make use of the Herschel Space Obser-vatory mission and is already coordinating one Herschel opentime key programme. Our plans also include expanding andemphasizing our theoretical research of star formation and in-terstellar cloud physics.

Spectropolarimetric observations of active late-type starsusing the high resolution Echelle spectrograph SOFIN at theNordic Optical Telescope, La Palma, Spain, have continuedsuccessfully. The time series of spectroscopic observationsfor surface temperature maps already extend over 18 years.Simultaneous local and global MHD modelling and modeldevelopment has been actively carried out, applications rang-ing from the solar dynamo activity to the active rapid rotatorsfollowed up by the observational programme, also includingMHD turbulence in accretion disks around pre- or protostel-lar cores, and molecular clouds and star-forming regions ingalaxies.

1.2 Progress and highlights of scientific resultsin 2009

(for references see the list of publications)

1.2.1 Magnetic activity in stars and circumstellar discs

We have successfully continued the investigation of the mag-netic field structure, especially the polarity of the field in spotsof two active longitudes, in active late-type stars (detectedearlier on by the group using surface temperature maps andnamed as ”active star Hale rule”). Spectroscopic observa-

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tions, based on which surface temperature maps have beeninverted, were started in 1991 with the high resolution spec-trograph SOFIN at the Nordic Optical Telescope, La Palma.The time series collected since is one of the few most exten-sive and complete existing data sets to study long-term vari-ability (cycles) in active late-type stars. An important devel-opment is the magnetic inversions based on new spectropo-larimetic data with upgraded spectropolarimeter and reduc-tion software, giving the first observational proof for the the-oretical prediction of the magnetic field polarity. The work isdone in collaboration with astronomers in Uppsala, Sweden,and Potsdam, Germany, most of the collaborators originallyhaving worked in Helsinki Observatory and/or Oulu Univer-sity. We have also continued the research on the behaviourof solar activity using sunspot data over 400 years, from theMaunder minimum to the present one. This is also gener-ally important because the solar activity has now been in verylong minimum and solar irradiance to Earth’s atmospere hasdecreased.

Simultaneously to the observations, local and global MHDmodels (PENCIL-CODE, MEFISTO; Korpi, Kapyla, Lilje-strom, Lindborg, Snellman) have been developed and uti-lized, to be able to investigate the transformation from solar-like dynamo activity to the activity seen in the active rapid ro-tators. Numerical modeling has yielded new results in a vari-ety of systems: local turbulence models have been utilized tostudy the turbulent transport of angular momentum (Snellmanet al. 2009, Korpi et al. 2009 in press), and numerical studiesof convection have, for the first time, revealed a large-scaledynamo (Kapyla et al. 2009a,b,c). The latter project was ac-cepted to the DEISA-DECI programme (CONVDYN PId byKorpi), from which 900 000 CPU hours of computing timewas granted and used during the year 2009. An internationalconference on the topic of Astrophysical Magnetohydrody-namics was organised by the MHD-group in Kiljava, Nurmi-jarvi, Finland, during 6.–10. of April 2009, with roughly 50participants from 13 different countries.

1.2.2 Interstellar clouds

Molecular line and NIR study of cometary clouds. Cometaryshape is common in the interstellar space. The objects rangefrom tiny globulettes embedded in HII regions to parsec sizedcometary globules and to cometary shaped star forming re-gions like Corona Australis. We are using molecular line ob-servations and NIR imaging to study the properties of thesesources (size, mass, density, dynamics, star formation) to gaininsight to their formation mechanism.

Even though Cometary globule 12 (CG 12) has been clas-sified as a cometary globule it is in fact a medium- and lowmass star forming region 210 pc above the Galactic plane.To complement our earlier molecular line studies (Haikala et.al 2006 and Haikala and Olberg 2007) NIR J, H, and Ksimaging obtained with SOFI at the La Silla NTT telescope

was used to analyse the stellar content and the structure ofCG 12. A color coded SOFI image of CG 12 is shown in 1.Several new members and member candidates of the CG 12stellar cluster were found. The new members include in par-ticular a highly embedded source with a circumstellar disk orshell. The central source of the known collimated molecu-lar outflow in CG 12 and an associated “hourglass”-shapedobject due to reflected light from the source were also de-tected. HIRES-enhanced IRAS images were used togetherwith SOFI JHKs imaging to study the two associated IRASpoint sources. Two new 12 µm sources coinciding with NIRexcess stars were detected in the direction of IRAS 13546–3941. The IRAS 13547–3944 emission at 12 and 25 µm orig-inates in the Herbig AeBe star h4636n and the 60 and 100 µmemission from an adjacent cold source. The study will appearin A&A (Haikala and Reipurth 2009, in press).

Cometary Globule 1 is the archetype cometary globulein the Gum nebula. NTT SOFI NIR Js, H, and Ks imag-ing and stellar photometry is used to analyse the structureof CG 1 and the extinction of stars in its direction (Haikalaand Makela). Preliminary results include an embedded, pre-viously unknown protostar in the globule head. The observedmaximum extinction in the cloud is ∼10 magnitudes in vi-sual. Like in the case of CG 12 HIRES enhanced IRAS im-ages were used together with SOFI JHKs imaging to study theassociated IRAS point source, 07178-4430. This point sourceresolves into two separate sources. The 12 and 25 µm emis-sion comes from the Herbig AeBe star NX Puppis and the60 and 100 µm emission from the adjacent, newly detectedprotostar.

Scattered Hα from interstellar clouds. Lehtinen, Ju-vela & Mattila have identified an undocumented large translu-cent cloud, detected by means of its enhanced radiation onthe SHASSA (Southern H-Alpha Sky Survey Atlas) survey.They compared the observed Hα surface brightness of thecloud with predictions of a radiative transfer model, by us-ing the WHAM (Wisconsin H-Alpha Mapper) survey as asource for the Galactic α interstellar radiation field illumi-nating the cloud. Visual extinction through the cloud is de-rived from 2MASS J, H and K band photometry. Far-infraredISOSS (ISO Serendipitous Survey), IRAS and DIRBE datawas used to study the thermal emission of dust, and LAB(The Leiden/Argentine/Bonn Galactic HI Survey) was usedto study 21 cm HI emission associated with the cloud. Radia-tive transfer calculations of the Galactic diffuse Hα radiationindicated that the surface brightness of the cloud can be ex-plained solely by radiation scattered off dust particles in thecloud. The maximum visual extinction through the cloud isabout 1.4 mag. The cloud is found to be associated with 21 cmHI emission at a velocity ∼ −9 km s−1. The total molecularmass of the cloud is about 310–460 solar masses. There wasno sign of star formation in this cloud. The distance of thecloud is from the Hipparcos data estimated to be ∼ 75 pc,making it one of the closest translucent molecular clouds.

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Figure 1: Colour coded SOFI image of CG 12. The J, H, and Ks bands are coded in blue, green and red, respectively. Squareroot scaling has been used to better bring out the faint surface brightness structures.

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Magnetic fields in interstellar clouds. Studies were com-pleted of the polarized sub-millimeter emission from dust grainsin interstellar clouds. In a magnetic field, dust grains remainaligned as long as their rotation speed is significantly largerthan their thermal rotation speed. The grains are believed tobe spinned up mainly by radiative torques. The efficiencyof radiative torques was investigated using magnetohydrody-namic cloud simulations and detailed radiative transfer mod-elling (Pelkonen et al. 2009). Results indicate large spatialvariations in the polarization efficiency. In particular, in denseclouds, the dust emission is not likely to probe magnetic fieldsdeeper than a few magnitudes in AV.

Through Zeeman effect, magnetic fields cause splitting ofsome radio lines. Because the split components have oppositecircular polarization, the line-of-sight component of the mag-netic field can be estimated from the Stokes I and V spectra.With radiative transfer modelling, three-dimensional magne-tohydrodynamic simulations could be compared with existingmeasurements of the Zeeman effect in cloud cores (Lunttilaet al. 2009). Good agreement was found between models ofsuper-Alfvenic turbulence, combined with self-gravity, andavailable observations of OH molecule lines. This suggeststhat the average magnetic field of molecular clouds may below and supports the idea of turbulence as a central factorbehind the formation of self-gravitating cloud cores.

1.2.3 Prestellar cores and star formation

Infrared dark clouds as precursors to high-mass stars andstar clusters. The so-called infrared dark clouds (IRDCs),which are identified as extinction features against the brightmid-infrared (MIR) Galactic background radiation, are likelyto represent very early stages of high-mass star/star clusterformation. In particular, some of the IRDCs may harbourhigh-mass starless cores (HMSCs), which provide the besttargets to study the initial conditions of high-mass star forma-tion. We have mapped the IRDC G304.75+01.32 in the 870µm dust continuum emission with the LABOCA bolometeron APEX. The obtained LABOCA map is presented in Fig. 2(Miettinen & Harju 2009, submitted). Twelve clumps wereidentified from the 870 µm map. Star formation has alreadystarted in the cloud as four of the clumps are associated withinfrared (MSX and/or IRAS) point sources. The remainingeight clumps are MIR dark. The masses of these MIR darkclumps, ∼ 40 − 200 M¯, are sufficiently large to enable high-mass star formation. Thus, some of them could be candidatesof being/harbouring HMSCs. The submillimetre map of thecloud also enabled us to study the clump mass and spatialdistributions. The clump masses in G304.74 were comparedwith the clump mass spectra from more extensive surveys ofIRDCs. It was found that the clump mass distributions inG304.74 and in several other IRDCs probably represent thesubsamples of the same parent distribution. Also clump sep-arations in different IRDCs are comparable to each other, and

also to the corresponding random distributions. This suggeststhat the fragmentation length-scale does not vary much fromcloud to cloud. The results of this study support the scenariothat the origin of IRDCs, and their further fragmentation intosmaller subunits is caused by supersonic turbulence in accor-dance with results from giant molecular clouds.

Chemical modelling of prestellar cores. Taking advan-tage of recently published chemical rate coefficients for theH+3 + H2 reacting system (Hugo et al. 2009, J. Chem. Phys.,130, 164302), we have developed chemical models to calcu-late chemical abundances in prestellar cores. Chemical evo-lution in the cores affects, among other things, the observ-able emission radiation from these objects, and thus chemicalmodels can be used to constrain the properties of the cores bycomparing model predictions with observations.

One such comparison is presented in Fig. 3. In the Fig-ure, an observation by Harju et al. (2008) of line emissionproduced in the H2D+ 110 - 111 transition is plotted againstthe model prediction of Sipila et al. (2009, in press). Theagreement between the observation and the model predictionis good, even though the chemical model in this case includesonly the lightest elements. This result is consistent with thedepletion of heavy substances toward the centers of prestellarcores, as has been widely discussed in the literature.

1.2.4 The Planck and Herschel satellite projects

The Planck and Herschel satellites were launched success-fully in May 2009. By the end of 2009, the first data werereceived from both satellites.

We participate in several science projects within the PlanckSurveyor satellite consortium. The main emphasis is on stud-ies of dense interstellar clouds and especially their cold andcompact cloud cores. The population of cold cores (Tdust <12 K) is still poorly known. Planck is the first space bornemission that has the sensitivity and the resolution necessaryfor the study of the cold core population over the whole sky.At the end of 2009, Planck has already scanned a significantfraction of the whole sky and the preliminary analysis of theobservations has resulted in the detection of hundreds of newcold cores.

We are coordinating a Herschel Open Time Key Programme,where a sample of the Planck-detected cores are investigatedin more detail using the Herschel PACS and SPIRE instru-ments. Herschel can observe wavelengths close to the peakof dust emission, λ ∼ 100 − 500 µm. Compared to Planck,Herschel has much higher spatial resolution. This makes itpossible to study the internal structure of the selected coresand to determine their evolutionary stages and their relationto future star formation. The key programme was awarded∼151 hours of observing time on the Herschel satellite. Themain observations are expected to start at the end of 2010.However, a few cores were already mapped as part of theHerschel Science Demonstration Phase and the initial results

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Figure 2: LABOCA map of the 870 µm dust continuum emission from the IRDC G304.74. The green and black plus signsmark the positions of the IRAS and MSX point sources, respectively.

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Figure 3: Model predictions for the line emission producedin the ground-state transitions of ortho-H2D+ (372 GHz, top)and para-D2H+ (692 GHz, bottom) from the prestellar coreOph D as observed with APEX (Sipila et al. 2009, in press).The H2D+ line is plotted against the observed profile (dottedcurve, Harju et al. 2008). Both transitions are potential toolsof prestellar core studies with ALMA.

were presented in a workshop in December 2009.We participate in several other Planck science projects,

including the study of nearby galaxies. We are also involvedin the Herschel key programme HiGal that is going to map alarge fraction of the plane of our Galaxy.

1.2.5 Extragalactic Background Light

Search for the optical Extragalactic Background Light.Using our understanding of the light scattering in dense in-terstellar clouds of dust, we have been developing a methodfor the detection of the optical extragalactic background light.This is the so-called “shadow of a dark cloud method”. Basedon our previous photometric EBL observing program we havedeveloped a spectroscopic analogy for it. This new tech-nique utilizes the difference between the spectra of the dif-fuse galactic scattered light (absorption line spectrum) andthe EBL (pure continuum spectrum with possible discontinu-ities). For the spectroscopic observing program we (Mattila,Lehtinen, Vaisanen) earlier received 20 hours observing timeat ESO VLT telescope and FORS instrument. For the ESOPeriod 82, 18.5 hours were again allocated but only a fewhours were realised in 2008/09.

The modelling of the FORS spectra requires knowledgeof the spectrum of the Local Interstellar Radiation Field (ISRF).A new population synthetic spectral model is being devel-oped along the lines of an earlier model by Mattila based onthe high-resolution stellar spectrum library STELIB (Borgneet al. 2003, A&A 4002, 433) and on stellar distribution pa-rameters derived from HIPPARCOS and other recent data byFlynn et al. (MNRAS 372, 1149, 2006). An excellent fitis found between the ISRF spectrum thus derived and theobserved scattered light spectrum of the dark nebula Lynds1642, our target for the VLT FORS spectroscopy.

Far-infrared Extragalactic Background Light. Usingdata from the ISOPHOT instrument of the ISO satellite, wehave completed a study of the extragalactic far-infrared back-ground light at 90, 150 and 180 µm (Juvela, Mattila et al.2009, the ISOPHOT EBL project). The signal represents asignificant fraction of the cosmic energy output from starsthat has been reprocessed by interstellar dust and is redshiftedto far-infrared wavelengths. Our study is the first independentmeasurement of the absolute surface brightness of the cos-mic infrared background radiation (CIRB) obtained since theCOBE result some ten years earlier. Our values are in agree-ment with the published COBE results, confirming the inten-sity of this extragalactic component at a level of ∼1 MJy sr−1

at wavelengths ∼150–180 µm.Identification of far-infrared sources at the North Galac-

tic Pole. As a follow-up of the far-infrared extragalactic back-ground light (ISOPHOT EBL) project Vaisanen (SALT, SouthAfrica), Juvela, Mattila et al.(2009) have performed observa-tions of the far-infrared (FIR) sources detected as part of thatproject. We have observed the fields at the North Galactic

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Pole region in the optical and near-IR, and complement thesedata with Sloan Digital Sky Survey SDSS photometry, andspectroscopy where available, and present identifications ofthe 25 FIR sources which reach down to 150 mJy in all threeISOPHOT bands at 90, 150 and 180 µm. Identifications aredone by means of full spectral energy density fitting to allsources in the FIR error circle areas. Approximately 80 percent are identified as star-forming or star-bursting galaxies atredshifts z<0.3. We also found that more than half of thecounterparts have disturbed morphologies, and some 40 percent are blends of two or more nearby star-forming galaxies.The blended sources have an effect on the FIR source counts.In particular, taking into account realistic confusion or blend-ing of sources, the differential FIR counts move down by afactor of 1.5 and steepen in the 100 to 400 mJy range.

1.3 External financing and resources2009: Person-months of work: 184

Academy of Finland: 440 000 eMinistry of Education: 100 000 eFoundations: 28 500 e

1.4 Tests of learningPelkonen, Veli-Matti

Ph.D. thesis: Two views on interstellar dust: near-infrared scattering and polarized thermal dust emis-sion; 2009, University of Helsinki, Department of As-tronomy

Kainulainen, JouniPh.D. thesis: Studies of the star-forming struc-

tures in the dense interstellar medium: a view by dustextinction; 2009, University of Helsinki, Departmentof Astronomy

Lehtinen, JyriM.Sc. thesis: Continuous period search method

and its application to stellar photometry; 2009, Univer-sity of Helsinki, Department of Astronomy

Suutarinen, AleksiM.Sc. thesis: CH- ja OH-molekyylien

pylvastiheyksien valinen korrelaatio tahtienvalisessamolekyylipilvessa TMC-1; 2009, University ofHelsinki, Department of Astronomy

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1.5 Visits abroadHackman, Thomas

NORDITA workshop “Solar and stellar dynamosand cycles”, Stockholm, Sweden, 5.–7.10.2009, 3 days

NOT OPC Meeting 4.-5.6.2009, Lund, Sweden,3.–6.6.2009, 4 days

NOT OPC Meeting, La Palma, Spain, 4.–8.12.2009, 5 days

Haikala, LauriESO STC Meeting, Garching, Germany, 21.–

23.4.2009, 3 daysESO ESAC Meeting, Garching, Germany,

15.6.2009, 1 dayUniversity of Stockholm,Stockholm. Sweden

23.–24.11.2009, 2 days

Harju, JormaEuropean ALMA Science Advisory Committee,

ESO, Garching, Germany, 8.–10.1.2009; 3 daysObservations with the Effelsberg 100-m telescope,

Germany, 23.–26.11.2009, 4 daysI. Physikalisches Institut, Universitat zu Koln,

27.11.2009, 1 day

Juvela, MikaAKARI Meeting, University of Tokyo, Japan,

14.–23.2.2009, 10 daysPlanck Satellite working group meeting,

Toulouse, France, 31.3.–5.4.2009, 6 daysASTROSIM project Steering Committee meeting,

Paris, 11.–12.9.2009; 2 daysPlanck Core Team and Consortium Meetings,

Bologna, Italy, 1.–7.11.2009; 7 daysIPAC, Pasadena, USA, 12.–19.11.2009; 8 daysHerschel workshop meeting, Madrid, Spain, 13.–

19.12.2009, 7 days

Kainulainen, JouniMax Planck Institut fur Astronomi, Heidelberg,

Germany, 13.–16.1.2009, 4 days

Korpi, MaaritPI of the NORDITA-programme ’Solar and stel-

lar dynamos and cycles’, Stockholm, Sweden, 27.9–17.10.2009, 20 days

’MHD days’ AIP, Potsdam, Germany, 7.–11.12.2009, 5 days

Kapyla, Petri5.–12.2.2009 NORDITA, Stockholm, Sweden24.–30.5.2009 NORDITA, Stockholm, Sweden18.–22.8.2009 NORDITA, Stockholm, Sweden30.8.–5.9.2009 ‘Natural Dynamos’, Stara Lesna,

Slovakia27.9.–25.10.2009 ‘Solar and stellar dynamos and

cycles’, NORDITA, Stockholm, Sweden7.–11.12.2009 ‘MHD-Days’, AIP, Potsdam, Ger-

many

Liljestrom, AnneCASA workshop, ESO Headquarters, Garching,

Germany, 10.–13.5.2009, 4 days

Lindborg, MarjaanaIAU General Assembly, Rio de Janeiro, Brazil,

3.–14.8.2009, 11 daysNORDITA, Stockholm, Sweden, 5.–9.10.2009, 5

daysSEAC 2009, Alexandria, Egypt, 28.-31.10.2009,

4 days

Lunttila, TuomasRadiative Transfer workshop, Gent, Belgium,

18.–22.8.2009, 5 days

Malinen, JohannaAKARI Meeting, University of Tokyo, Japan,

14.–23.2.2009, 10 daysHerschel workshop, Madrid, Spain and Planck

meeting, Toulouse, France, 25.3.–5.4.2009, 12 daysHerschel data processing and Initial results,

Madrid, Spain, 13.–19.12.2009, 7 days

Mattila, KaleviESO Committee of Council, Garching, Germany,

2.–3.3.2008ESO Council, Vienna, Austria, 3.–4.6.2008ESO Council, Garching, Germany, 9.–10.12.2008

Miettinen, OskariCASA Workshop, ESO Headquarters, Garching,

Germany, 10.–13.5.2009, 4 daysObservations with the Effelsberg 100-m telescope,

Germany, 23.–26.11.2009, 4 days

Makela, MinjaUniversity of Stockholm, Sweden, 23.–

24.11.2009, 2 days

10

Pelkonen, Veli–MattiPlanck WG7 Meeting, Toulouse, France, and Her-

schel Workshop, Madrid, Spain, 1.–3.4.2009 and 25.3.-.5.4.2009, 12 days

Snellman, JanNORDITA, Stockholm, Sweden, 27.9.–

3.10.2009, 7 days

Tuominen, IlkkaIAU General Assembly, Rio de Janeiro, Brazil,

3.–14.8.2009, National representative of Finland, 11days

NORDITA, Stockholm, Sweden, 4.–13.10.2009,10 days

Nathalie YsardPlanck consortium meeting, Bologna, Italy, 3.–

7.11.2009, 5 days

1.6 Papers read at scientific conferences, sym-posia, meetings etc.Hackman, Thomas

”Detecting differential rotation from spectro-metric and photometric observations”, NORDITA-programme Solar and stellar dynamos and cycles,Stockholm, Sweden, 27.9.–23.10.2009

Korpi, Maarit”Mean-field dynamo models of rapidly rotat-

ing stars”, NORDITA-programme Solar and stel-lar dynamos and cycles, Stockholm, Sweden, 27.9–23.10.2009

”Dynamos and magnetic field detachement inthermally unstable interstellar flows”, AstrophysicalMagnetohydrodynamics, Kiljava, Finland

Kapyla, Petri“Large-scale dynamos in local models of con-

vection”, Astrophysical Magnetohydrodynamics’, 6.–10.4.2009 Kiljavanranta, Nurmijarvi, Finland

“Bridging the gap between local and globalconvection simulations”, Natural Dynamos, 30.8.–5.9.2009, Stara Lesna, Slovakia

“Convection-driven dynamos in spherical wedgegeometry”, Solar and stellar dynamos and cycles,27.9.–25.10.2009, NORDITA, Stockholm, Sweden

“Convection-driven dynamos in spherical wedgegeometry”, MHD-Days, 8.–9.12.2009, AIP, Potsdam,Germany

Liljestrom, Anne”Predicting turbulent stresses in a local disk

model”, Astrophysical Magnetohydrodynamics, Kil-java, Finland

Lindborg, Marjaana”Surface temperature maps for II Peg during

1999–2002”, Lindborg, M., Korpi, M.J., Tuominen, I.,Ilyin, I., Piskunov, N., IAU General Assembly, Sympo-sium 264, 3-7/8 Solar and stellar variability-Impact onEarth and Planets, Rio de Janeiro, Brazil, poster

”Stellar magnetic fields: observations and nonlin-ear modelling” Astrophysical Magnetohydrodynamics,Kiljava, Finland

”Jatinkirkkojen aurinkosuuntauksia”, PenttiKoivusen juhlaseminaari, Oulu University, Oulu,Finland, 2.10.2009

Tuominen, Ilkka”Self-consistent magnetic Doppler imaging of ac-

tive stars”, Kochukhov O., Piskunov N., Ilyin I.,Tuominen I. IAU General Assembly, Symposium 264,3-7/8 Solar and stellar variability-Impact on Earth andPlanets, Rio de Janeiro, Brazil, poster

”Some notes on sunspot statistics”, NORDITA-programme Solar and stellar dynamos and cycles,Stockholm, Sweden, 27.9–23.10.2009

1.7 Visiting academicsHaikala, Lauri

Shimariji, Yoshito, PhD, National Radio Observa-tory, Japan, 31.8.–6.9.2009

Harju, JormaDr. Stephan Hotzel, GRS mbH, Koln, 15.–30.8.

Korpi, MaaritProf. Anvar Shukurov, University of Newcastle,

10.–19.4.2009, 9 days

Kapyla, PetriDhrubaditya Mitra, PhD, Queen Mary College,

University of London, UK, 20.–22.7.2009

Mattila, KaleviProfessor Adolf Witt, Ritter Astrophysical Re-

search Center, University of Toledo, USA, 23.–29.5.2009

Professor Douglas Whittet, Department ofPhysics and Astronomy, Rensselaer PolytechnicInstitute, Troy, NY, USA, 27.9.–6.10.2009

11

Dr. Martin Haas, Astronomische Institut, Univer-sitat Bonn, Germany, 24.–28.8.2009

Dr. Karl D. Gordon, Space Telescope Science In-stitute, Baltimore, USA, 22.–25.2.2009

Vaisanen, Petri, PhD, South African Astronomi-cal Observatory, 30.11.–4.12.2009

Tuominen, IlkkaJaan Pelt, PhD, Tartu Observatory, Estonia, 14.–

19.6.2009Nadezhda Zolotova, PhD, St. Petersburg State

University, Russia 7.–10.12.2009

1.8 Membership in scientific and scholarly so-cietiesHaikala, Lauri

ESO Scientific Technical Committee, EuropeanALMA Scientific Advisory Committee, February2009–

Harju, JormaEuropean ALMA Scientific Advisory Committee,

until February 2009

Mattila, KaleviOdin Science Team, 1991–ISO/ISOPHOT Consortium, 1991–Planck LFI, 1998–Finnish National Committee for Astronomy

(IAU), Finland, chairEuropean Southern Observatory, CouncilTuorla Observatory of University of Turku, advi-

sory board, ChairCouncil of the European Southern Observatory:

Delegate of FinlandInternational Astronomical Union, Commission

21: SOC member

Tuominen, IlkkaFinnish National Committee for Astronomy

(IAU), representative for Finnish Academy of Scienceand Letters

Deutsche Forschunggemeinschaft, expertNational Committee for Astronomy for Finland:

Chairman

1.9 Other activitiesMattila, Kalevi

Faculty of Science, University of Helsinki, Fac-ulty Board Member

1.10 Refereeing and Other Publishing Activi-ties

Korpi, MaaritAstronomische Nachricten, Germany, refereeAstronomische Nachricten, Germany, guest editor

Kapyla, PetriAstrophysical Journal, refereeAstronomy & Astrophysics, referee

Mattila, KaleviAstronomy and Astrophysics, France, refereeAstrophysical Journal, USA, refereeMonthly Notices of the R.A.S., U.K., referee

Tuominen, IlkkaAstronomy and Astrophysics, member of board of

directors

12

2 High Energy AstrophysicsProject number 91525005Research agreements Academy of Finland

TekesESA, ESO

Type of research Basic research, share: 50 %Development work, share: 50 %

Director of research Docent Huovelin, JuhaniTelephone 19122948Fax 19122952E-mail Juhani.Huovelin@Helsinki.FiSenior (Ph.D. or higher) Juhani Huovelin, Docent

Jukka Nevalainen, docentLinnea Hjalmarsdotter, Ph.D.Seppo Korpela, D.Sc. (Tech.)

Ph.D. student(s) Lauri Alha, Ph.Lic.Karri Koljonen, M.Sc.Tuomas Lehto, M.Sc.Sami Maisala, M.Sc.Tero Oittinen, M.Sc.Otto Solin, M.Sc.(Tech.)Auni Somero, M.Sc.Tuure Takala, M.Sc.Mikko Vaananen. M.Sc.

Students Jussi AhorantaEero EskoJasmin Haikonen

Associated scientists Pasi Hakala, docent (Turku)Diana Hannikainen, Docent

(Helsinki Univ. of Technology)Rami Vainio, Ph.D.

2.1 General approachThe activities of high energy astrophysics research of HESA(High Energy Space Astronomy) are divided into three areas,(1) fundamental science, (2) development of new instrumentsfor space research, and (3) development of data analysis soft-ware. The first part consists of scientific return (guaranteedtime) from the instrument projects (INTEGRAL, SMART-1,Chandrayaan-1), complemented by data from other satellites(e.g. XMM-Newton, HST, RXTE, Chandra, Suzaku). Thesecond part is a continuation to the ongoing hardware projectsincluding research also in detector physics. The science top-ics addressed include coronae and flaring in active stars andthe Sun, and studies of clusters of galaxies and related ques-tions in cosmology. In particular, the very broad spectral cov-erage (INTEGRAL) and the possibility for a very long mon-itoring (SMART-1, Chandrayaan-1), coupled to the sophisti-cated modelling, are the key ingredients of the science. De-velopment of new instruments is a natural continuation to theongoing projects, providing valuable access to the guaranteedtime also in the future. The aim is to utilise the advances in in-strument performances carried along with bigger telescopes,larger field-of-view and decreased noise of new systems in thefuture plans of ESA, NASA and JAXA (IXO, InternationalX-ray Observatory, and Lobster). The specific improvementsthat are meaningful are: (1) the huge enhancement of sensi-tivity and spectral resolution with IXO, which enables stud-ies of X-ray spectra of Galactic sources with the same qual-ity we nowadays can investigate the solar corona, (2) almostfull sky field-of-view in X-rays with moderate spectral res-

olution (Lobster)) giving a freedom to select targets of in-terest and study their temporal and spectral behaviour in alltime scales from seconds to months. The systems under de-velopment are: (1) The SIXS instrument for BepiColombo(2) common DPU and onboard software of SIXS and MIXSinstruments for BepiColombo, and (3) SQUID readout elec-tronics for the X-ray Spectrometer (XRS) for IXO. The ac-tivities of HESA have resulted in the completion of threespace science instruments, and a successful aunch of IN-TEGRAL, SMART-1 and Chandrayaan-1 missions with ourworking hardware onboard. The scientific use of INTEGRALresulted in a number of scientific papers published in 2003-8. SMART-1/XSM made effective observations of the Sunfrom March 2004 to August 2006. Several refereed paperson the instruments have already been published, and severalpapers on solar coronal science with very high quality datafrom XSM/SMART-1 are in preparation, and two PhD thesesare just under or close to submission. At present, the scientificutilization of INTEGRAL and SMART-1 continues. Obser-vation programs with other satellites (RXTE, XMM-Newton,Chandra, Suzaku) were continued.

The activities have also evolved and grown to a higherlevel of collaboration with new plans for instruments andsatellites, which combine the expertise and experience of thegroup and its collaborators. The wide scientific and techno-logical expertise within this framework have made it possibleto start planning bigger contributions in international spacescience programs, e.g. participation at PI level in the nextESA cornerstone mission to Mercury (BepiColombo). We arealso involved at Co-PI level in the India-ESA collaborativeMoon mission Chandaryaan-1 (launched in 2008 andendedin August 2009) with an XSM similar to that of SMART-1.The in-kind contribution of Finland*s entrance fee to ESOwas completed successfully by the Finnish Sampo project,and ESO continued to support the development of ESO Re-flex by our team with one and a half year*s extension withESO funding. We also submitted as a coordinator an EU col-laborative project proposal (E-SQUID)for the Space Call 3in December 2009. The goal for the aimed research is todevelop a super-sensitive readout electronics with SQUID-technology to space detectors in the X-rays, optical and farinfrared/submm wavelengths. The main collaborators in thisproject plan are VTT, Max Institute, University of Leicester,SRON, and IPHT from Jena, Germany.

2.2 Science topics2.2.1 The solar corona

The aim of this research is to disentangle the properties of thehot solar corona by analysing the X-ray spectra obtained withour own instruments flying on-board space missions, likeXSM/SMART-1 and XSM/Chandrayaan-1. The hot coronaof the Sun radiates strongly in X-rays. The solar corona ex-

13

hibits in apparently random intervals very strong eruptions,which are called flares. Big flares are associated with strongenhancement of electromagnetic emission at all wavelengths,and large amounts of accelerated energetic particles. Theeruptions occur most frequently and they are strongest onaverage during Sunspot maximum. In solar flares and alsogenerally in the solar corona the radiation in X-rays domi-nates, which is due to the high temperature of the ionized gas(plasma). Our research aims at clarifying the physical mech-anism of the eruptions by examining the X-ray spectrum andits variation during flares, and by comparing different flares.Also time behaviour over longer time span is studied with theaim of studying the changes of the properties of solar coronaduring the Sunspot (11 years) cycle. The methods include de-veloping improved theoretical models based on extensive newvery high quality spectroscopic X-ray data. The observationsof the Sun are made with X-ray instruments on-board satel-lites. The most important of the instruments is the FinnishXSM X-ray spectrometer on the ESA*s SMART-1 satellite.In addition, data from the RHESSI and the GOES satellitesare used as complementary sources of information. After theend of SMART-1 operations (September 2006), more similardata has already been received from a Finnish solar monitoron the Indian Chandrayaan-1 mission (launched in Septem-ber 2008 and terminated operation in August 2009), and later,especially, with the Finnish solar monitor SIXS on ESA*sBepiColombo (launch August 2014), which all are projectslead by the HESA group. The data will enable obtaining athorough new insight in electromagnetic processes and X-rayemission mechanisms in hot coronal plasma of the Sun, andwill also form a basis in producing a realistic model databasefor modelling the X-ray spectra of other stars, with the aim ofunderstanding their coronae.

Figure 4: XSM sensor box (Alha, 2009)

2.2.2 Clusters of galaxies

Our research aims in characterising the thermal and nonther-mal processes in clusters of galaxies. We use this informationto derive the distribution of baryonic and dark matter in clus-ters and to constrain the cosmological parameters. We alsoderive properties of the relativistic electron populations andmagnetic fields in clusters. The main analysis tools utilizedby us are high resolution imaging and spatially resolved spec-troscopy of the hot intracluster gas. For this work we use X-ray and gamma-ray data of clusters of galaxies obtained withXMM-Newton, Suzaku and INTEGRAL satellites. We haveobtained observation time via our own proposals which wecombine with the available archival data.

Since clusters of galaxies are massive and hot, they inter-act with the Cosmic Microwave background via the Sunyaev-Zeldovich effect. In a working group of Planck satellite, weare planning the usage of this effect based on the Planck data.We are participating in a international project IACHEC whichaims at studying the cross-calibration of high energy satel-lites. JN is leading the cluster working croup of the project.Comparison of X-ray measurements of clusters of galaxiesallows us to estimate the calibration accuracy of different in-struments. We are currently developing cluster-based calibra-tion tools for the future X-ray missions.

2.3 Development of data analysis softwareESO-connected data analysis activities have also grown sig-nificantly since the beginning of Finland’s membership in2004. The project, called ESO-Sampo, conducted develop-ment of science data analysis environment for ESO. Four ITprofessionals worked full-time for the in-kind contributionin the period 1.1.2005- 31.1.2008 in a Tekes-funded projectat the Observatory, University of Helsinki, and have contin-ued the same work with partial funding from ESO until theend of September 2009. The main result of the project isthe ESO Reflex workflow engine, an advanced science anal-ysis environment which ESO plans to implement as standardESO software for the reduction of VLT and other ESO data.HESA team has also participated actively in the preparationof national technology return from ESO. These have alreadylead to a request from ESO to continue ESO Reflex devel-opment by partial ESO funding, and a parallel developmentof an application for other sciences and also commercial usewith Tekes funding, which continued until September 2009.Further, future activities from this are (1) a Tekes projectfor developing a Situation Awareness System using Multidi-mensional Information (MIFSAS), and (2) a proposal to theEU for a collaborative project called Combined Analysis ofMulti-Source Astronomical Data (CAMSAD).

14

2.4 External financing and resources2009: Man-months of work: 109

Academy of Finland: 110 000 eNational Technology Agency: 2 600 000 eUniversity of Helsinki: 17 000 eEuropean Southern Observatory: 46 000 e

2.5 Tests of learningKettula, Kimmo

M.Sc. thesis: Relativistic electron population ofthe Ophiuchus cluster of galaxies; 2009, University ofHelsinki, Department of Astronomy

2.6 Visits abroadEsko, Eero

MIS Workshop, The Netherlands, 11.–14.5.2009,4 days

Huovelin, JuhaniBepiColombo project meeting ESOC, Darmstadt,

Germany, 26.5.2009, 1 dayBepiColombo SWT meeting, Paris, France, 24.–

28.10.2009, 5 daysEU project preparatory meeting, SRON, The

Netherlands, 2.10.2009, 1 day

Korpela, SeppoBepiColombo meeting, Madrid, Spain, 14.–

16.1.2009, 3 daysAntenna field tests at Stevenage, U.K., 3.–

5.2.2009, 3 daysBepiColombo Mission, 7th MPO Science Work-

ing Group Meeting (MPO SWG-7), ESTEC, Newton2, 6./7. April 2009, 6.–7.4.2009, 2 days

MIXS Team Conference at University of Leices-ter, U.K., 31.5.–3.6.2009, 4 days

EU project preparatory meeting, The Netherlands,2.10.2009, 1 day

Maisala, SamiTaverna 2.0 workshop, University of Manchester,

U.K., 17.–20.2.2009, 4 daysESO-Reflex technical meeting, Garching, Ger-

many, 23.–24.4.2009, 2 daysESO Reflex Technical meeting, ESO, Garching,

Germany, 7.–9.7.2009, 3 days

Nevalainen, JukkaIACHEC meeting, Osaka, Japan, 22.–29.4.2009,

8 daysPlanck consortium meeting, CNR Conference

center, Bologna, Italy, 4.–8.11.2009, 5 days

Oittinen, TeroTaverna 2.0 workshop, University of Manchester,

U.K., 17.–20.2.2009, 4 daysESO technical discussions, Germany, 23.–

24.4.2009, 2 days

Takala, TuureTaverna 2.0 workshop, University of Manchester,

U.K., 17.–20.2.2009, 4 daysESO technical discussions, Germany, 23.–

24.4.2009, 2 days

Vainio, RamiEGU 2009, Vienna, Austria, 19.–24.4.2009, 6

daysBepiColombo SWG, ESTEC, Amsterdam, The

Netherlands, 6.–7.4.2009, 2 daysBepiColombo project meeting, ESOC, Darmstadt,

Germany, 26.5.2009BepiColombo SWT, Blois, France, 26.–

29.10.2009, 4 days

Vaananen, MikkoInvited AIP conference Talk, Big Island Hawaii,

USA, 30.4.–10.5.2009, 11 days

2.7 Membership in scientific and scholarly so-cietiesHuovelin, Juhani

Finnish COSPAR committee, FinlandResearch school for astronomy and space physics,

Finland, boardAcademy of Finland assessor pool, Finland, ex-

pertFinnish Space Committee (ANK), permanent ex-

pert

Nevalainen, JukkaPlanck Working Group 5, 30.3.2007–, expertInternational Astronomical Consortium for High

Energy Calibration, 9.5.2007–, expert

15

Figure 5: Media realisations with 4 × 106 particles with ρ = 0.55, Gc roughness (upper images) of (from left to right)σ/L = 0.012, l = 0.05, 0.25, 0.5, and fBm roughness (lower images) of σ/L = 0.012, H = 0.3, 0.5, 0.7. Parviainen andMuinonen (2009B1)

18

3 Planetary System ResearchProject number 02525008Research agreements Academy of FinlandType of research Basic researchDirector of research Professor Muinonen, KarriTelephone 19122941Fax 19122952E-mail Karri.Muinonen@Helsinki.FiResearch staff with a Ph.D. Karri Muinonen, Prof.

Kari Lumme, Prof. emer.Evgenij Zubko, Ph.D.Mark Paton, Ph.D.

Phd students Antti Penttila, Lic.S.Sc.Dagmara Oszkiewicz, M.Sc.Hannu Parviainen, M.Sc.Jani Tyynela, M.Sc.Hannakaisa Lindqvist, M.Sc.Jarkko Niemela, M.Sc.

Students Tuomo PieniluomaAssociated scientists Markku Poutanen, Prof. (Finnish Geodetic Institute

Lauri Pesonen, Prof.Jari Valkonen, Prof.Jouni Peltoniemi, Docent (Finnish Geodetic Institute)Timo Nousiainen, DocentJenni Virtanen, Ph.D. (Finnish Geodetic Institute)Mikael Granvik, Ph.D. (University of Hawaii)Johanna Torppa, Ph.D. (Geological Survey of Finland)Jyri Naranen, Ph.D. (Finnish Geodetic Institute)

3.1 Research activitiesResearch within the Planetary-System Research -group(PSR) at the University of Helsinki Observatory entails theo-retical, observational, and experimental studies on key top-ics of solar-system exploration. In fundamental planetaryphysics, PSR theoretical research is focussed on light scat-tering by single small particles, on multiple scattering bycomplex media of small particles, and the celestial mechan-ics of the few-body problem. Experiments have been car-ried out to measure backscattering characteristics of particu-late media (scatterometer at the Observatory), to assess theX-ray fluorescence by planetary-regolith analog samples (atthe Department of Physical Sciences), and to measure mete-orite spectra in visible and near-infrared wavelengths (at theGeological Survey of Finland and at the Finnish Geodetic In-stitute). Observations have been made using both space-basedand ground-based telescopes.

The numerical method for computing coherent backscat-tering by complex particulate media developed at UHO hasbeen successfully applied to polarimetric observations oftransneptunian objects (TNOs). Boehnhardt et al. describedpolarimetry in planetary science, in particular, tying the VLTadvances to future needs with ELTs. At ESO/VLT, PSRhas continued to participate in polarimetric observations ofcometary nuclei: these observations are the first-ever system-atic polarimetric observations of cometary nuclei.

Penttila and Lumme have studied the effects of the prop-erties of porous media on light scattering (Penttila & Lumme,2009). They have used numerical wave-optical methods forlight scattering simulations to asses the effect of porosity onthe optical properties of paper coating. Both constant poros-

ity profile and media with porosity contrast between layersat different depths are considered. This can lead to optimalpaper coating structures for both brightness and gloss.

Juuti et al. (2009) have studied the spectral properties andsurface uniformity of black glass gloss references. Commer-cial glossmeters are usually provided with a gloss referenceand in some cases the reference is derived from black glass.Light reflection from the reference depends both on the com-plex refractive index and on the surface quality, such as theroughness and the cleanness of the black glass. The complexrefractive index, as a function of wavelength, was measuredwith an ellipsometer, and the reflectance at standardized glossmeasurement angles was calculated for the case of nonpolar-ized light. Furthermore, the gloss variation of the referencewas detected with a diffractive-optical-element-based gloss-meter.

Lindqvist et al. (2009B1) studied light scatteringby coated, concave-hull-transformed clusters of spheresand Gaussian-random-sphere particles. Nousiainen et al.(2009B1) focused on optical modeling of thin calcite flakesusing Discrete-Dipole Approximation. Zubko et al. (2009B1)studied light scattering by agglomerated debris particles com-posed of highly absorbing material, and the applicability ofDDA to conductive particles. Muinonen et al. (2009B1) in-troduced diffuse scatterers in the ray-optics treatment for lightscattering by particles large compared to wavelength.

Tyynela et al. (2009B1) carried out radar-scattering com-putations from spherical and spheroidal particles, as well asclusters of spherical particles in the C-band using the discrete-dipole approximation method (DDA). The results were com-pared to those from exact methods.

Parviainen and Muinonen (2009B1) studied volume andsurface shadowing in particulate random media, providinga realistic light-scattering model for rough particulate sur-faces. PSR continued an in-depth study on the interpretationof the SMART-1/AMIE photometry. Naranen et al. (2009B1)studied regolith effects in planetary X-ray fluorescence spec-troscopy concentrating on laboratory studies at 1.7 - 6.4 keV.Huovelin et al. (2009B1) and Fraser et al. (2009B1) de-scribed the Solar Intensity X-ray and particle Spectrometer(SIXS) and Mercury Imaging X-ray Spectrometer (MIXS)onboard the ESA BepiColombo mission to Mercury (launchin 2014). Rothery et al. (2009B1) described forecoming Mer-cury surface and compositional studies using BepiColombo.

In studies of asteroid phase curves, Muinonen et al.(2009, paper submitted to Icarus) presented methods for thederivation of empirical magnitude systems for asteroid phasecurves. Their goal is to develop a new magnitude system forasteroids, revising the two-parameter H, G magnitude systemcurrently adopted by IAU.

Establishing links between asteroids and meteorites isproblematic. Meteorites allow us to peer inside asteroids butwhich asteroids are we looking at? Reflectance spectra mea-surements are a popular remote sensing technique of asteroids

19

Figure 6: Lauri Jetsu and Karri Muinonen at the Observatory 175h anniversary reception, November 2009 (Photo: EvaIsaksson)

20

as they are relatively easy to do and provide information oncomposition. These can then be compared with reflectancespectra measurements of meteorites to find a match. How-ever, reflectance spectra measurements of asteroids are fromthe surface and this may be unrepresentative of the interiordue to surface effects and geological processes. Reflectancespectra of 27 meteorites, representing undifferentiated (C, H,L, LL, and E) to differentiated meteorites, were obtained us-ing a spectrometer at the Geological Survey of Finland. Fea-tures in the reflectance spectra were explored by Paton etal. (paper in preparation) to determine if they revealed diag-nostic features among the various meteorite groups and sub-groups, if they correlated with meteorite physical properties(e.g. mineralogy, density, porosity, or susceptibility) or withweathering or shock degree. Classification methods, usingthese non-destructive physical and spectral property measure-ments of meteorites, are developed for possible application tofuture remote sensing of asteroids and to strengthen the linkbetween meteorites and asteroids.

Oszkiewicz et al. completed a paper (D. Oszkiewicz, K.Muinonen, J. Virtanen, M.Granvik, Meteoritics and Plane-tary Science, in press, 2009) that introduces a new Markov-Chain Monte-Carlo orbital ranging method for poorly ob-served single-apparition asteroids with two or more astro-metric observations. The method has been applied to near-Earth, main-belt, and transneptunian objects. Obtained dis-tributions of orbital elements can then serve as a base inEarth impact probability computation, dynamical classifica-tion, ephemeris prediction, linking between apparitions prob-lems, and in other applications.

Granvik et al. M. Granvik, J. Virtanen, D. Oszkiewicz, K.Muinonen, Meteoritics and Planetary Science, in press, 2009)describe an open-source asteroid-orbit-computation softwarepackage called OpenOrb. In addition to the well-knownleast-squares method, OpenOrb contains both Monte-Carloand Markov-Chain Monte-Carlo versions of the statistical or-bital ranging method (Ranging) based on well-establishedBayesian inversion theory. As an example, OpenOrb wasused to search for candidate retrograde objects similar to2008 KV42 in the known population of transneptunian ob-jects.

PSR contributed to the preparation of the ESA astromet-ric cornerstone mission Gaia (launch in 2012): this entailedorbital-inverion software delivery to the Gaia Data Process-ing and Analysis Pipeline (DPAC) and further developmentof Markov-Chain Monte Carlo methods for inversion of fore-coming Gaia photometry for asteroid spin and shape charac-teristics. Preparations continued for a successful competitionof the Marco Polo near-Earth-object sample return missionwithin the ESA Cosmic Vision Programme, with PSR repre-sented in the ESA Science Study Team of the mission.

3.2 External financing and resources2009: Man-months of work: 100

Academy of Finland, ’Light Scattering by Solar-System Small Particles’:117 740 e

European Commission, ’European Leadership inSpace Astrometry’ (ELSA)’: 62 000 e

Tekes intelligent production technologies project :153 000 e

Tekes forest cluster project Re-engineering paper:21 000 e

3.3 Tests of learningNaranen, Jyri

Ph.D. thesis: Multiwavelength studies of regolitheffects in planetary remote sensing; 2009, University ofHelsinki, Department of Astronomy

Niemela, JarkkoM.Sc. thesis: Asteroid polarimetry: review and

new observations; 2009, University of Helsinki, De-partment of Astronomy

3.4 Visits abroadMuinonen, Karri

ELSA Mid-Term-Review meeting, Brussels, Bel-gium, 1.–5.2.2009, 5 days

Gaia GREAT network kick-off meeting, Cam-bridge, U.K., 25.–29.3.2009

1st Planetary Defense Conference, Granada,Spain, 26.4.–1.5.2009, 6 days

GAIA CU4 meeting, Turin, Italy, 28.–30.5.2009,3 days

IAU General Meeting, Rio de Janeiro, Brazil, 2.–15.8.2009, 14 days

Marco Polo mission meeting, Paris, France, 17.–21.5.2009, 5 days

International Symposium on Atmospheric LightScattering and Remote Sensing, Xian, China, 13.-17.7.2009, 5 days

Marco Polo Science Study team Meeting, ESTEC,The Netherlands, 9.–11.9.2009, 3 days

Marco Polo Science study team -meeting, ES-TEC/ESA, The Netherlands, 22.–24.9.2009

ELSA School ”The Techniques of Gaia”, Heidel-berg, Germany, 27.9.–3.10.2009, 7 days

Marco Polo -mission Science Study Team meet-ing, Paris, France, 30.11.–2.12.2009: 3 days

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Niemela, JarkkoObservations with NOT-telesscope, La Palma,

Spain, 28.7.–2.8.2009, 6 days,

Naranen, JyriEGU General Assembly 2009, Wien, Austria,

19.–25.4.2009, 7 daysSoft X-ray fluorescence spectroscopy workshop,

ESTEC,The Netherlands, 1.–2.9.2009BepiColombo 6th SWT meeting, Blois, France,

26.–30.10.2009, 5 days

Oszkiewicz, DagmaraELSA Mid-Term-Review meeting, Brussels, Bel-

gium, 1.–4.2.2009, 4 daysWorkshop dealing with technical concerns im-

posed by Gaia and DPCC host frame work, Paris Ob-servatory, France, 16.–18.2.2009, 3 days

1. ELSA secondment, Paris, France and 2.GREAT Kickoff meeting, Cambridge, U.K., 14.–27.3.2009, 14 days

1st Planetary Defense Conference, Granada,Spain, 23.4.–3.5.2009, 11 days

DPAC CU4 -meeting 7 28-29 May 2009 INAF,Osservatorio Astronomico di Torino, Italy, 27.–30.5.2009, 4 days

International Astronomical Union general assem-bly, Rio de Janeiro, Brazil 20.7.–15.8.2009, 26 days

International conference of Young Astronomers(ICYA), Krakow, Poland, 6.–19.9.2009, 14 days

ELSA School on the Techniques of Gaia, Heidel-berg, Germany, 27.9.–3.10.2009, 7 days

Gaia Coordination Unit 4 ”Object processing”The 8th Meeting, Lohrmann Observatory, Dresden,Germany, 11.–16.11.2009, 6 days

Parviainen, HannuEGU 2007, Austria, 18.–26.4.2009, 9 days

Zubko, E.Scientific collaboration with Ukrainian colleagues

Prof. Yu. Shkuratov and Dr. D. Petrov, Ukraine, 24.7.–17.8.2009, 25 days

Scientific discussion with Dr. G. Videen at AmyResearch Laboratory, (Adelphi, MD,USA) and partici-pation in 41st annual meeting of the Division for Plane-tary Sciences of the American Society, Fajardo, PuertoRico, USA, 29.9.–10.10.2009, 12 days

3.5 Papers read at scientific conferences, sym-posia, meetings etc.Oszkiewicz, Dagmara

”Asteroid orbits with Gaia using Markov-Chain Monte-Carlo ranging”, D. A. Oszkiewicz,K.Muinonen, J.Virtanen, M.Granvik (Granada, Spain,27.–30.4.2009), poster

”Time evolution of collision probabilities for 2004AS1 2008 TC3 2009 DD45.” D. A. Oszkiewicz,K.Muinonen, J.Virtanen, M.Granvik, IAU‘s XXVIIGENERAL ASSEMBLY, Rio de Janeiro (Brazil)3.–14.8.2009, poster

”Time evolution of collision probabilities for 2004AS1 2008 TC3 2009 DD45.” D. A. Oszkiewicz,K.Muinonen, J.Virtanen, M.Granvik, The Interna-tional Conference of Young Astronomers (ICYA) 7.–13.09.2009 Krakow, Poland, poster

”Time evolution of collision probabilities for 2004AS1 2008 TC3 2009 DD45.” D. A. Oszkiewicz,K.Muinonen, J.Virtanen, M.Granvik, FinCOSPAR 3.–5.9.2009 Rokua National Park, poster ”Asteroid rang-ing with Markov-Chain Monte-Carlo” D. A. Os-zkiewicz, K. Muinonen, J.Virtanen, M.Granvik (In-stitut Seminar, Astronomical Observatory, Poznan,Poland, 8.1.2009)

”Asteroid orbital inversion using statistical meth-ods”, D. A. Oszkiewicz, K. Muinonen (Brussels, Bel-gium, 2.2.2009)

”Asteroid orbits with Gaia using MCMC rang-ing” D. A. Oszkiewicz, K. Muinonen, J. Virtanen, M.Granvik (Geophysics Days, 3.–14.5.2009, Helsinki)

”Asteroid orbits with Gaia using MCMC rang-ing” D. A. Oszkiewicz, K. Muinonen, J. Virtanen, M.Granvik (CU4#7 meeting, 29.05.2009, Torino)

”MCMC orbital ranging and its applications”, D.A. Oszkiewicz, K. Muinonen, J. Virtanen, M. Granvik, ELSA School, Heideberg 28.9.–2.10.2009

”MCMC ranging – convergence diagnostics”,D. A. Oszkiewicz, PSR group seminar presentation5.10.2009, Helsinki

”Metsahovi-Kumpula project, a platform for si-multaneous observation of meteors and air-plane track-ing” D. A. Oszkiewicz, Jyri Naranen, 9.11.2009, PSRgroup seminar, Helsinki

”DU456 progress report” D. A. Oszkiewicz,K. Muinonen, CU4#8 meeting, Dresden (12.–13.11.2009), Germany

22

Penttila, Antti”Simulation of optical properties and NFC-filler

structures”. Seminar of Intelligent and Resource-Efficient Production Technologies (EffTech) pro-gramme, Espoo, Dipoli Congress Centre, 6.9.2009

3.6 Visiting academicsMuinonen, Karri

Dr. Harrison Schmitt, Apollo 17 Astronaut, April16, 2009

Prof. Nicolas Thomas, University of Bern, March4–7, 2009

Prof. Claes-Ingvar Lagerkvist, Uppsala Univer-sity, March 6, 2009

Dr. Michael Weiler, Paris Observatory, March 2–13, 2009

Dr. Mikael Granvik, University of Hawaii, May 7,2009

Mr. Benoit Frezouls, CNES, France, June 15–19,2009

Mr. Christophe Ordenovic, Observatoire de laCote d’Azur, June 15–19, 2009

Dr. Maria Gritsevich, ESA/ESTEC, November16–17, 2009

3.7 Membership in scientific and scholarly so-cietiesMuinonen, Karri

International Astronomical Union, Commission20 Organizing Committee, 2006–, France

ELSA Steering Committee (European Leadershipin Space Astrometry), 1.10.2006–, Sweden

International Astronomical Union, Task Group onAsteroid Magnitudes, 2006–, France

International Astronomical Union, Task Groupon Asteroid Polarimetric Albedo Calibration, 2006–,France

Marco Polo Science Study Team, ESA, 2007–,France

International Astronomical Union, Task Group onGeophysical and Geological Properties of Asteroidsand Cometary Nuclei, 2008–, France, chair

3.8 Refereeing and Other Publishing ActivitiesMuinonen, Karri

Icarus, USA, refereePlanetary and Space Science, The Netherlands,

refereeAstronomy and Astrophysics, France, refereeJournal of Quantitative Spectroscopy & Radiative

Transfer, referee

23

Figure 7: Students at the Observatory lecture hall, November 2009 (Photo: Eva Isaksson)

24

4 Lectures in 2009Course (English) Course (Finnish)

spring termbasic studies perusopinnot

Universe now Maailmankaikkeus nyt (lectured in English)Universe now Maailmankaikkeus nyt (lectured in Finnish)Universe now Maailmankaikkeus nyt (lectured in Swedish)Basics of observational astronomy I Havaitsevan tahtitieteen peruskurssi IBasic astronomy Tahtitieteen perusteetPractical methods in astronomy Tahtitieteen kaytannon menetelmia

subject studies aineopinnotStructure of the Milky Way Linnunradan rakenne

advanced studies syventavat opinnotAstrobiology AstrobiologiaScattering of light on small particles II Valon sironta pienhiukkasista IIPlanetary geophysics Planetaarinen geofysiikkaAdvanced course in dynamics Dynamiikan jatkokurssiInfrared astronomy InfrapunatahtitiedeSubmillimetre astronomy AlimillimetritahtitiedeMagnetohydrodynamics Magnetohydrodynamiikka

other muutClimate changes of planet Earth Planeetta Maan ilmastonvaihtelutTelling about astronomy – a course on Kerro tahtitieteesta – populaarikirjoittamisen

popularization kurssiIntroduction to project management Johdatus projektityohonChronology: history and calendars Ajanlasku: historiaa ja kalentereita

seminars seminaaritAstrophysics seminar Astrofysiikan seminaariPlanetary system research seminar Planeettakunnan tutkimusseminaari

autumn termbasic studies perusopinnot

Universe now Maailmankaikkeus nyt (lectured in Finnish)Basics of observational astronomy II Havaitsevan tahtitieteen peruskurssi IIBasic astronomy Tahtitieteen perusteet

subject studies aineopinnotX-ray analysis of galaxy clusters Galaksijoukkojen rontgenanalyysiStructure and evolution of stars Tahtien rakenne ja kehitysBasic course in astrophysics Astrofysiikan peruskurssiPhysics of the Solar system Aurinkokunnan fysiikka

advanced studies syventavat opinnotHigh energy astrophysics Suurenergia-astrofysiikkaaInterstellar medium Tahtienvalinen aine

lecture series on astrobiology – astrobiologian luentosarjaInterferometry at radio and infrared Radio- ja infrapuna-alueen interferometria

wavelengthsother muut

Introduction to astrobiology Johdatus astrobiologiaanIntroduction to expert tasks Johdatus asiantuntijatehtaviinIntroduction to applications of Johdatus pallotahtitieteen sovelluksiin

spherical astronomyseminars seminaarit

Astrophysics seminar Astrofysiikan seminaariPlanetary system research seminar Planeettakunnan tutkimusseminaari

25

5 LibraryLibrarian Eva Isaksson, M.Sc.E-mail astro-library@helsinki.fi

5.1 Library MergerThe Observatory library will merge with the Kumpula Cam-pus Library in January 2010. To prepare the merger, a work-group consisting of librarians and astronomers was set up todecide on best practices and priorities.

The Observatory library collection is exceptional and pro-vides a comprehensive view on two centuries of astronomicalresearch and publishing activities. The Kumpula Campus li-brary is a modern library serving research, teaching and stud-ies. It has limited space available for older collections nolonger in active use, thus it is a major challenge to preservethese historical collections.

The transfer of books to Kumpula was started in Novem-ber 2009, and serials will be transferred in early 2010.

Figure 8: Books awaiting transfer

5.2 LISA VI ConferenceThe Library and Information Services in Astronomy (LISA)conferences, arranged every 4th year, bring together astron-omy librarians, publishers and information specialists fromall over the world.

The librarian acts as co-chair of the Scientific OrganizingCommittee of the next LISA conference to be held in Pune,India in February 14-17, 2010.

5.3 Membership in scientific and scholarly so-cietiesIsaksson, Eva

Library and Information Services in Astronomy(LISA) VI SOC, co-chair

26

6 Observatory Board 2007–2009DirectorDoc. Lauri Jetsu

ProfessorsProf. Kalevi MattilaProf. Karri Muinonen (starting 8.4.2009)

StaffDoc. Mika JuvelaProf. Karri Muinonen (until 8.4.2009)Doc. Juhani Huovelin (starting 8.4.2009)

StudentsSuvi Jentze (until 26.8.2008)Karri Koljonen (until 7.1.2009)Jussi Aaltonen (starting 26.8.2009)Merli Lahtinen (starting 7.1.2009)

Figure 9: Some participants of the last Observatory Board meeting 15.12.2009. From left to right: Hannikainen, Aaltonen,Huovelin, Jetsu, Toriseva, Muinonen. (Photo: Jenni Toriseva)

27

7 Publications7.1 Articles in refereed journals (B1)

1. Ahoranta, J.; Uunila, M.; Huovelin, J.; Andersson, H.;Vainio, R.; Virtanen, A.; Kettunen, H.: Radiation hardnessstudies of CdTe and HgI2 for the SIXS particle detector on-board the BepiColombo spacecraft. Nuclear Instruments andMethods in Physics Research A 605 (2009): 344-349.

2. Alha, L.: Off-solar X-ray observations and a new detectorconcept with a concentrator optics. Nuclear Instruments andMethods in Physics Research A 604 (2009): 497-504.

3. Alha, L.; Huovelin, J.; Nygård, K.; Andersson, H.; Esko, E.;Howe, C.J.; Kellett, B.J.; Narendranath, S.; Maddison, B.J.;Crawford, I.A.; Grande, M.; Shreekumar, P.: Ground cali-bration of the Chandrayaan-1 X-ray Solar Monitor (XSM).Nuclear Instruments and Methods in Physics Research A 607(2009): 544-553.

4. Boehnhardt, H.; Tozzi, G. P.; Sterzik, M.; Bagnulo, S.;Kolokolova, L.; Muinonen, K.: Polarimetry in Planetary Sci-ence – A Step Forward with the VLT and a Need for the ELTs.Earth, Moon, and Planets 105 (2009): 95-100

5. Crawford, I. A.; Joy, K. H.; Kellett, B. J.; Grande, M.; Anand,M.; Bhandari, N.; Cook, A. C.; d’Uston, L.; Fernandes, V.A.; Gasnault, O.; Goswami, J.; Howe, C. J.; Huovelin, J.;Koschny, D.; Lawrence, D. J.; Maddison, B. J.; Maurice,S.; Narendranath, S.; Pieters, C.; Okada, T.; Rothery, D.A.; Russell, S. S.; Sreekumar, P.; Swinyard, B.; Wieczorek,M.; Wilding, M.: The scientific rationale for the C1XS X-rayspectrometer on India’s Chandrayaan-1 mission to the moon.Planetary and Space Science 57 (2009): 725-734.

6. Grande, M.; Maddison, B. J.; Howe, C. J.; Kellett, B. J.;Sreekumar, P.; Huovelin, J.; Crawford, I. A.; d’Uston, C. L.;Smith, D.; Anand, M.; Bhandari, N.; Cook, A.; Fernandes,V.; Foing, B.; Gasnaut, O.; Goswami, J. N.; Holland, A.;Joy, K. H.; Kochney, D.; Lawrence, D.; Maurice, S.; Okada,T.; Narendranath, S.; Pieters, C.; Rothery, D.; Russell, S. S.;Shrivastava, A.; Swinyard, B.; Wilding, M.; Wieczorek, M.:The C1XS X-ray Spectrometer on Chandrayaan-1. Planetaryand Space Science 57 (2009) p. 717-724.

7. Fraser, G.; Carpenter, J.; Rothery, D. A.; Muinonen, K. and41 others: The Mercury Imaging X-ray Spectrometer (MIXS)on BepiColombo. Planetary and Space Science, in press(2009).

8. Granvik, M.; Virtanen, J.; Oszkiewicz, D.; Muinonen, K.:OpenOrb: Open-source asteroid-orbit-computation softwareincluding Ranging. Accepted to MAPS (2009).

9. Hakala, Pasi; Hjalmarsdotter, Linnea; Hannikainen, DianaC.; Muhli, Panu: Light curve morphology study of UW CrB– evidence for a 5 d superorbital period. Monthly NoticesR.A.S. 394 (2009): 892-899.

10. Hjalmarsdotter, L.; Zdziarski, A. A.; Szostek, A.; Han-nikainen, D. C.: Spectral variability in Cygnus X-3. MonthlyNotices of the R.A.S. 392 (2009): 251-263.

11. Howe, C. J.; Drummond, D.; Edeson, R.; Maddison, B.;Parker, D. J.; Parker, R.; Shrivastava, A.; Spencer, J.; Kellett,

B. J.; Grande, M.; Sreekumar, P.; Huovelin, J.; Smith, D. R.;Gow, J.; Narendranath. K. C., S.; d’Uston, L.: Chandrayaan-1 X-ray Spectrometer (C1XS) – Instrument design and tech-nical details. Planetary and Space Science 57 (2009): 735-743.

12. Hubbard, A.; Del Sordo, F.; Kapyla, P.; Brandenburg, A.:The α effect with imposed and dynamo-generated magneticfields. Monthly Notices R.A.S. Online Early

13. Huovelin, J.; Vainio, R.; Andersson, H.; Valtonen, E.; Alha,L.; Malkki, A.; Grande, M.; Fraser, G. W.; Kato, M.; Koski-nen, H.; Muinonen, K.; Naranen, J.; Schmidt, W.; Syrjasuo,M.; Anttila, M.; Vihavainen, T.; Kiuru, E.; Roos, M.; Pel-tonen, J.; Lehti, J.; Talvioja, M.; Portin, P.; Prydderch , M.:Solar Intensity X-ray and particle Spectrometer (SIXS). Plan-etary and Space Science, available online Dec. 2008

14. Juuti, M.; Tuononen, H.; Penttila, A.; Myller, K.; Lumme,K.; Peiponen, K.-E.: Spectral properties and surface unifor-mity of black glass gloss references. Optical Engineering 48(2009): 033603-033603-5 (2009).

15. Juvela, M.; Mattila, K.; Lemke, D.; Klaas, U.;Leinert, C.;Kiss, Cs.: Determination of the cosmic far-infrared back-ground level with the ISOPHOT instrument. Astron. As-trophys. 500 (2009): 763-768

16. Juvela, M.; Pelkonen, V.-M.; Porceddu, S.: A Corona Aus-tralis cloud filament seen in NIR scattered light. II. Com-parison with sub-millimeter data. Astron. Astrophys. 505(2009): 663-671.

17. Kainulainen, J. T.; Alves, J. F.; Beletsky, Y.; Ascenso, J.;Kainulainen, J. M.; Amorim, A.; Lima, J.; Marques, R.;Moitinho, A.; Pinhao, J.; Rebordao, J.; Santos, F. D.: Uncov-ering the kiloparsec-scale stellar ring of NGC 5128. Astron.Astrophys. 502 (2009): L5-L8

18. Kainulainen, J.; Lada, C. J.; Rathborne, J. M.;Alves, J. F.:The fidelity of the core mass functions derived from dust col-umn density data. Astron. Astrophys. 497 (2009): 399-407

19. Korhonen, H.; Hubrig, S.; Berdyugina, S. V.; Granzer, Th.;Hackman, T.; Scholler, M.; Strassmeier, K. G.; Weber, M.:First measurement of the magnetic field on FK Com and itsrelation to the contemporaneous star-spot locations. MonthlyNotices of the Royal Astronomical Society, Volume 395, Is-sue 1, pp. 282-289.

20. Korpi, M.J.; Kapyla, P. J.; Vaisala, M. S.: Influence of Ohmicdiffusion on the excitation and dynamics of MRI. Astron.Nachr. 331 (2010): 34.

21. Kapyla, P.; Brandenburg, A.: Turbulent Dynamos with Shearand Fractional Helicity. The Astrophys. J. 699 (2009): 1059-1066

22. Kapyla, P.J.; Korpi, M. J.; Brandenburg, A.: The alpha effectin rotating convection with sinusoidal shear. Mon. Not. R.Astron. Soc. (2009), early view.

23. Kapyla, P.; Korpi, M. J.; Brandenburg, A.: Alpha effect andturbulent diffusion from convection. Astron. Astrophys. 500(2009): 633-646

24. Kapyla, P.; Korpi, M.;Brandenburg, A.: Large-scale Dy-namos in Rigidly Rotating Turbulent Convection. The As-trophys. J. 697 (2009): 1153-1163

28

25. Kapyla, P. J.; Korpi, M. J.; Brandenburg, A.; Mitra, D.;Tavakol, R.: Convective dynamos in spherical wedge geom-etry. Astron. Nachr. 331 (2010): 73.

26. Kapyla, P.; Mitra, D.; Brandenburg, A.: Numerical studyof large-scale vorticity generation in shear-flow turbulence.Physical Review E 79 (2009) id. 016302

27. Liljestrom, A. J.; Korpi, M. J.; Kapyla, P. J.; Brandenburg,A.; Lyra, W.: Turbulent stresses as a function of shear rate ina local disk model. Astronomische Nachrichten 330 (2009):92-99.

28. Lindqvist, H.; Muinonen, K.; Nousiainen, T.: Light scatter-ing by coated Gaussian and aggregate particles. Journal ofQuantitative Spectroscopy & Radiative Transfer 110 (2009):1398-1410.

29. Lunttila, T.; Padoan, P.; Juvela, M.; Nordlund, Å.: The Super-Alfvenic Model of Molecular Clouds: Predictions for Mass-to-Flux and Turbulent-to-Magnetic Energy Ratios. The As-trophys. J. 702 (2009): L37-L41

30. Lyytinen, J.; Jetsu, L.; Kajatkari, P.; Porceddu, S.: Detec-tion of real periodicity in the terrestrial impact crater record:quantity and quality requirements. Astron. Astrophys. 499(2009): 601-613

31. Miettinen, O.; Harju, J.; Haikala, L. K.; Kainulainen, J.; Jo-hansson, L. E. B.: Prestellar and protostellar cores in OrionB9. Astron. Astrophys. 500 (2009): 845-860

32. Mitra, D.; Kapyla, P. J.; Tavakol, R.; Brandenburg, A.: Alphaeffect and diffusivity in helical turbulence with shear. Astron.Astrophys. 495 (2009): 1-8

33. Muinonen, K.; Nousiainen, T.; Lindqvist, H.; Muoz, O.;Videen, G.: Light scattering by Gaussian particles with inter-nal inclusions and roughened surfaces using ray optics. Jour-nal of Quantitative Spectroscopy & Radiative Transfer 110(2009): 1628-1639.

34. Nevalainen, J.; Eckert, D.; Kaastra, J.; Bonamente, M.; Ket-tula, K.: XMM-Newton and INTEGRAL analysis of theOphiuchus cluster of galaxies. Astron. & Astrophys. in press(2009), arXiv: astro-ph/0910.1364

35. Nousiainen, T.; Zubko, E.; Niemi, J. V.; Kupiainen, K.;Lehtinen, M.; Muinonen, K.; Videen, G.: Single-scatteringmodeling of thin, birefringent mineral-dust flakes using thediscrete-dipole approximation. Journal of Geophysical Re-search 114 (2009): CiteID D07207

36. Naranen, J.; Carpenter, J.; Parviainen, H.; Muinonen, Karri;Fraser, G.; Peura, M.; Kallonen, A.: Regolith effects in plan-etary X-ray fluorescence spectroscopy: Laboratory studies at1.7 - 6.4 keV. Advances in Space Research 44 (2009): 313-322.

37. Oszkiewicz, D.; Muinonen, K.; Virtanen, J.; Granvik, M.:Asteroid ranging with Markov-Chain Monte-Carlo. Ac-cepted to MAPS (2009).

38. Padoan, P.; Juvela, M.; Kritsuk, A.; Norman, M. L.: ThePower Spectrum of Turbulence in NGC 1333: Outflows orLarge-Scale Driving? The Astrophysical Journal Letters,Volume 707, Issue 2, pp. L153-L157 (2009).

39. Parviainen, H.; Muinonen, K.: Bidirectional reflectance ofrough particulate media: Ray-tracing solution. Journal ofQuantitative Spectroscopy & Radiative Transfer 110 (2009):1418-1440.

40. Pelkonen, V.-M.; Juvela, M.; Padoan, P.: Predictions of po-larized dust emission from interstellar clouds: spatial varia-tions in the efficiency of radiative torque alignment. Astron.Astrophys. 502 (2009): 833-844

41. Penttila, A.; Lumme, K.: The effect of the properties ofporous media on light scattering. Journal of QuantitativeSpectroscopy & Radiative Transfer 110 (2009): 1993-2001.

42. Rathborne, J. M.; Lada, C. J.; Muench, A. A.; Alves, J. F.;Kainulainen, J.; Lombardi, M.: Dense Cores in The PipeNebula: An Improved Core Mass Function. The Astrophys.J. 699 (2009): 742-753

43. Rothery, D.; Marinangeli, L.; Anand, M.; Carpenter, J.;Christensen, U.; Crawford, I. A.; De Sanctis, M. C.; Epi-fani, E. M.; Erard, S.; Frigeri, A.; Fraser, G.; Hauber, E.;Helbert, J.; Hiesinger, H.; Joy, K.; Milillo, A.; Mitrofanov, I.;Muinonen, K.; Naranen, J.; Pauselli, C.; Potts, P.; Warell, J.;and Wurz, P. Mercury’s surface and composition to be stud-ied by BepiColombo. Planetary and Space Science, in press(2009).

44. Savolainen, P.; Hannikainen, D. C.; Vilhu, O.; Paizis, A.;Nevalainen, J.; Hakala, P.: Exploring the spreading layerof GX 9+9 using RXTE and INTEGRAL. Monthly NoticesR.A.S. 393 (2009): 569-578.

45. Snellman, J. E.; Kapyla, P. J.; Korpi, M. J.; Liljestrom, A. J.:Reynolds stresses from hydrodynamic turbulence with shearand rotation. Astron. Astrophys. 505 (2009): 955-968.

46. Tyynela, J.; Nousiainen, T.; Goke, S.; Muinonen, K.: Model-ing C-band single scattering properties of hydrometeors usingdiscrete-dipole approximation and T-matrix method. Jour-nal of Quantitative Spectroscopy & Radiative Transfer 110(2009): 1654-1664.

47. Valtonen, E.; Peltonen, J.; Dudnik, O. V.; Kudin, A. M.; An-dersson, H.; Borodenko, Yu. A.; Eronen, T.; Huovelin, J.;Kettunen, H.; Kurbatov, E. V.; Lehti, J.; Nenonen, S.; Rossi,M.; Vainio, R.; Virtanen, A.: Radiation Tolerance Tests ofSmall-Sized CsI(Tl) Scintillators Coupled to Photodiodes.IEEE Transactions on Nuclear Science, vol. 56, issue 4, pp.2149-2154

48. Vilhu, O.; Hakala, P.; Hannikainen, D. C.; McCollough, M.;Koljonen, K.: Orbital modulation of X-ray emission lines inCygnus X-3. Astron. Astrophys. 501 (2009): 679-686

49. Vaananen, M.; Schultz, J.; Nevalainen, J.: Flare loop sizes inyoung suns. Baltic astronomy 18 (2009): 1

50. Zubko, E.; Kimura, H.; Shkuratov, Y.; Muinonen, K.; Ya-mamoto, T.; Okamoto, H.; Videen, G.: Effect of absorptionon light scattering by agglomerated debris particles. Jour-nal of Quantitative Spectroscopy & Radiative Transfer 110(2009): 1741-1749.

29

7.2 Papers in conference publications andcompilations (B2)

1. Carroll, T. A.; Kopf, M.; Strassmeier, K. G.; Ilyin, I.; Tuomi-nen, I.: Zeeman-Doppler imaging of II Peg Cosmic MagneticFields: From Planets, to Stars and Galaxies, Proceedings ofthe International Astronomical Union, IAU Symposium, Vol-ume 259, p. 437-438.

2. Cooray, A. and 48 coauthors, including Mattila, K.: A NewEra in Extragalactic Background Light Measurements: TheCosmic History of Accretion, Nucleosynthesis and Reioniza-tion. Astro2010: The Astronomy and Astrophysics DecadalSurvey, Science White Papers, no. 54.

3. David, L.; Nevalainen, J.: A Comparison of Cluster Tempera-tures Derived from Chandra and XMM-Newton. Proceedingsof the 2009 Chandra Calibration Review (2009).

4. Fletcher, Andrew; Korpi, M.; Shukurov, A. Dynamicallydominant magnetic fields in the diffuse interstellar mediumCosmic Magnetic Fields: From Planets, to Stars and Galax-ies, Proceedings of the International Astronomical Union,IAU Symposium, Volume 259, p. 87-88

5. Foing, B. H.; Koschny, D.; Grieger, B.; Josset, J.-L.; Beau-vivre, S.; Grande, M.; Huovelin, J.; Keller, H. U.; Mall, U.;Nathues, A.; Malkki, A.; Noci, G.; Sodnik, Z.; Kellett, B.;Pinet, P.; Chevrel, S.; Cerroni, P.; de Sanctis, M. C.; Barucci,M. A.; Erard, S.; Despan, D.; Muinonen, K.; Shevchenko,V.; Shkuratov, Y.; Ellouzi, M.; Peters, S.; Borst, A.; Baxkens,F.; Boche-Sauvan, L.; Mahapatra, P.; Almeida, M.; Frew, D.;Volp, J.; Heather, D.; McMannamon, P.; Camino, O.; Racca,G.: SMART-1 Results and Targets for LRO. Lunar Recon-naissance Orbiter Science Targeting Meeting, held June 9-11,2009 in Tempe, Arizona. LPI Contribution No. 1483, p.39-40

6. Grande, M.; Kellett, B. J.; Maddison, B. J.; Sreekumar, P.;Huovelin, J.; Howe, C. J.; Crawford, I. A.; Narendranath,S.: Initial Results from the C1XS X-Ray Spectrometer onChandrayaan-1. 40th Lunar and Planetary Science Confer-ence, (Lunar and Planetary Science XL), held March 23-27,2009 in The Woodlands, Texas, id.1840

7. Kochukhov, O.; Piskunov, N.; Ilyin, I.; Tuominen, I.: Mag-netic Doppler Imaging of Active Stars. Cool stars, stellarsystems and the Sun: Proceedings of the 15th CambridgeWorkshop on Cool Stars, Stellar Systems and the Sun. AIPConference Proceedings, Volume 1094, pp. 720-723 (2009).

8. Kochukhov, Oleg; Piskunov, N.; Ilyin, I.; Tuominen, I.: Mag-netic Doppler imaging of II Peg. Cosmic Magnetic Fields:From Planets, to Stars and Galaxies, Proceedings of the In-ternational Astronomical Union, IAU Symposium, Volume259, p. 439-440

9. Kopf, M.; Carroll, T. A.; Ilyin, I.; Strassmeier, K. G.; Tuomi-nen, I.: A New Zeeman-Doppler Imaging Code for ActiveLate Type-stars. An Application to II Peg. Solar Polarization5: In Honor of Jan Stenflo ASP Conference Series, Vol. 405,proceedings of the conference held 17-21 September, 2007at Centro Stefano Franscini–Monte Verit, Ascona, Switzer-land. Edited by Svetlana V. Berdyugina, K. N. Nagendra,and Renzo Ramelli. San Francisco: Astronomical Society ofthe Pacific, 2009., p. 517

10. Korhonen, H.; Berdyugina, S. V.; Ilyin, I. V.; Strassmeier, K.G.; Hackman, T.: Spot evolution and active longitudes on FKCom: more than a decade of detailed surface mapping Mag-netic Fields in the Universe II: From Laboratory and Stars tothe Primordial Universe. Supplementary CD (Eds. A. Es-quivel, J. Franco, G. Garca-Segura, E. M. de Gouveia DalPino, A. Lazarian, S. Lizano, & A. Raga) Revista Mexicanade Astronoma y Astrofsica (Serie de Conferencias) Vol. 36,pp. CD323-CD327 (2009).

11. Korhonen, H.; Hubrig, S.; Kovarii, Z.; Weber, M.; Strass-meier, K.; Hackman, T.; Wittkowski, M.: The Applicationof FORS1 Spectropolarimetry to the Investigation of CoolSolar-like Stars The Messenger, 138 (2009): 15-18

12. Martindale, A.; Pearson, J. F.; Fraser, G. W.; Carpenter,J. D.; Willingale, R.; Stevenson, T.; Whitford, C.; Gian-nini, F.; Fairbend, R.; Seguy, J.; Sclater, E.; Delgado, I.;Kaipiainen, M.; Nenonen, S.; Pilvi, T.; Schyns, E.; Bul-loch, C.; Sawyers, C.; Muinonen, K.: The Mercury ImagingX-ray Spectrometer: optics design and characterisation- In-struments and Methods for Astrobiology and Planetary Mis-sions XII. Edited by Hoover, Richard B.; Levin, Gilbert V.;Rozanov, Alexei Y.; Retherford, Kurt D.. Proceedings of theSPIE, Volume 7441 (2009), pp. 744117-744117-9 (2009).

13. Martindale, A.; Pearson, J. F.; Whitford, C.; Fraser, G. W.;Rothery, D. A.; Talboys, D.; Carpenter, J. D.; Stevenson,T.; Bunce, E.; Fairbend, R.; Seguy, J.; Sclater, E.; Del-gado, I.; Dixon, A.; Treis, J.; Mas-Hesse, J. M.; San Juan,J. L.; Muinonen, K.; Sawyers, C.; Bulloch, C.; Schyns,E.: The Mercury Imaging X-ray Spectrometer: instrumentoverview. Instruments and Methods for Astrobiology andPlanetary Missions XII. Edited by Hoover, Richard B.; Levin,Gilbert V.; Rozanov, Alexei Y.; Retherford, Kurt D.. Proceed-ings of the SPIE, Volume 7441 (2009)., pp. 744115-744115-9 (2009). (SPIE Homepage)

14. Okkonen J. and Ridderstad M., ”Jatinkirkkojen aurinkosu-untauksia”, in Ei kiveakaan kaantamatta – Juhlakirja PenttiKoivuselle, eds. J. Ikaheimo and S. Lipponen, PenttiKoivusen juhlakirjatoimikunta, Tornion kirjapaino, 129-136(2009)

15. Pelkonen, V.-M.; Juvela, M.; Padoan, P.; Mattila, K.: Twoviews on dust: polarized thermal dust emission and near-infrared scattering. Proceedings of the conference The Evolv-ing ISM in the Milky Way and Nearby Galaxies, The FourthSpitzer Science Center Conference, Eds.: K. Sheth et al.

16. Tuominen, Ilkka; Korpi, Maarit J.; Kapyla, Petri J.; Lindborg,Marjaana; Ilyin, Ilya: Stellar nonlinear dynamos: observa-tions and modelling. Cosmic Magnetic Fields: From Planets,to Stars and Galaxies, Proceedings of the International Astro-nomical Union, IAU Symposium, Volume 259, p. 417-418

17. Witt, A. N.; Murthy, J.; Gustafson, B. Å. S.; Baggaley, W.J.; Dwek, E.; Levasseur-Regourd, A.-C.; Mann, I.; Mattila,K.; Watanabe, J.: Commission 21: Light of the Night Sky.Transactions IAU 4 27A, Reports on Astronomy 2006-2009.Edited by Karel van der Hucht. Cambridge: Cambridge Uni-versity Press, 2008, p. 171-173.

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8 Academic degrees 1995–2009Year Degree Supervisor(s)1995 Ph.D. Pasi Hakala O. Vilhu1995 Ph.D. Juri Poutanen D.I. Nagirner, O. Vilhu1995 M.Sc. Diana Hannikainen O. Vilhu1996 Ph.Lic. Paivi Harjunpaa T. Liljestrom, K. Mattila1997 Ph.D. Mika Juvela K. Mattila1997 M.Sc . Thomas Hackman I. Tuominen1997 M.Sc. Asko Palviainen J. Harju, K. Mattila1998 Ph.D. Kimmo Lehtinen J. Harju, K. Mattila1999 Ph.D. Diana Hannikainen O. Vilhu1999 Ph.D. Jukka Piironen K. Muinonen1999 M.Sc. Jere Kahanpaa M. Juvela, K. Mattila1999 M.Sc. Juho Schultz P. Hakala1999 M.Sc. Johanna Torppa M. Kaasalainen1999 M.Sc. Jenni Virtanen K. Muinonen2000 Ph.D. Jukka Nevalainen O. Vilhu2001 Ph.D. Petri Vaisanen K. Mattila2001 M.Sc. Peter Johansson K.J. Donner, P. Vaisanen2003 Ph.D. Sanna Kaasalainen K. Muinonen, J. Piironen2003 M.Sc. Mikael Granvik K. Muinonen2003 M.Sc. Jyri Naranen J. Peltoniemi, J. Piironen2003 M.Sc. Cajus Pomren J. Harju2003 M.Sc. Kyosti Ryynanen M. Kaasalainen, J. Piironen2003 M.Sc. Jani Tyynela K. Lumme2004 M.Sc. Jouni Kainulainen J. Harju, K. Lehtinen, K. Mattila2004 M.Sc. Jari Rantala M. Kaasalainen2005 Ph.D. Thomas Hackman L. Jetsu, I. Tuominen2005 Ph.D. Jenni Virtanen K. Muinonen2005 M.Sc. Kristiina Byckling P. Hakala2005 M.Sc. Oskari Miettinen J. Harju, L. Haikala2006 Ph.D. Paivi Harjunpaa J. Harju, K. Mattila2006 Ph.D. Petri Kapyla M. Korpi, I. Tuominen2006 Ph.D. Juho Schultz D. Hannikainen, O. Vilhu2006 M.Sc. Onni Jarvinen K. Muinonen, J. Piironen2006 M.Sc. Tuomas Lehto P. Heinamaki, P. Teerikorpi2006 M.Sc. Anne Liljestrom J. Harju, M. Korpi2006 M.Sc. Tuomas Lunttila M. Juvela2006 M.Sc. Hannu Parviainen K. Muinonen2006 M.Sc. Auni Somero P. Hakala2007 M.Sc. Karri Koljonen D. Hannikainen2007 M.Sc. Johanna Mynttinen D. Hannikainen2007 M.Sc. Sebastian Porceddu L. Jetsu, T. Markkanen2007 M.Sc. Petri Savolainen D. Hannikainen2007 M.Sc. Minttu Uunila J. Huovelin, R. Vainio2008 Ph.D. Mikael Granvik K. Muinonen2008 Ph.D. Linnea Hjalmarsdotter D. Hannikainen2008 Ph.D. Johanna Torppa M. Kaasalainen, K. Muinonen2008 Ph.Lic. Lauri Alha J. Huovelin2008 M.Sc. Hannakaisa Erkkila K. Muinonen2008 M.Sc. Mikko Eronen L. Haikala2008 M.Sc. Perttu Kajatkari D. Hannikainen2008 M.Sc. Mari Kolehmainen D. Hannikainen2008 M.Sc. Marjaana Lindborg M. Korpi, P. Kapyla, I. Tuominen2008 M.Sc Joonas Lyytinen L. Jetsu2008 M.Sc. Minja Makela M. Juvela, K. Lehtinen, K. Mattila2008 M.Sc. Arttu Raja-Halli J. Nevalainen2008 M.Sc. Minerva Schultz J. Harju, M. Juvela2008 M.Sc. Tuure Takala J. Huovelin, E. Kyrola2008 M.Sc. Maija Ylosmaki J. Harju, M. Juvela2009 Ph.D. Jouni Kainulainen J. Alves, M. Juvela, K. Mattila2009 Ph.D. Jyri Naranen K. Muinonen2009 Ph.D. Veli-Matti Pelkonen M. Juvela2009 M.Sc. Jarkko Niemela K. Muinonen

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M.Sc. Ph.Lic. Ph.D.1995 1 – 21996 – 1 –1997 2 – 11998 – – 11999 4 – 22000 – – 12001 1 – 12002 – – –2003 5 – 12004 2 – –2005 2 – 22006 6 – 32007 5 – –2008 11 1 32009 1 – 3

– Number of degrees completed between 1995 and 2009

– Number of articles in refereed journals (Closed diamonds: Scale on the right)– Budget funding from the University of Helsinki (Closed squares: Scale on the left ke)– Project funding for Observatory (Closed circles: Scale on the left ke)– Project funding for Observatory including industrial subcontracts (Open circles: Scale on the left ke)

Editor’s note:Some material is missing from this annual report due to the fact that it had to be finished already in December 2009.

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A group of Observatory faculty, students and staff at a Xmas party with some of their future colleagues from Kumpula campu,sDecember 4, 2009. (Photo: Eva Isaksson)