February 2014 SOCIETY JOURNAL · 2014-02-03 · SOCIETY JOURNAL February 2014 February Monthly...

SOCIETY JOURNALFebruary 2014

February Monthly MeetingMonday 10 February at 8.00pM

dr. eliot Quataert provides an overview of the modern understanding of our origins in astrophysics.

the story begins in the infant universe, which we now know was remarkably smooth compared to what we see around us today, with only tiny

differences in its properties from one part to another. by contrast, in the present universe there are enormous differences in the properties of

matter in different locations. dr. Quataert describes how the universe has evolved to its current state, emphasizing how gravity reigns supreme

and builds up the planets, stars, and galaxies required for biological evolution to proceed.

dr. Quataert is professor of astronomy and director, theoretical astrophysics Center at uC berkeley.

this video lecture was recently given (oct 2013) as part of the Silicon Valley Lecture Series.

“How the Universe Went from Smooth to Lumpy: The Modern Origins Story”Video LeCture with dr. eLiot Quataert (uniVerSity oF CaLiFornia, berkeLey)

2 society journal, February 2014

Astronomy popularizer John Dobson diesBy Michael E. Bakich, Astronomy.com

Dobson revolutionized the hobby with his altitude-azimuth mount for reflecting telescopes and his efforts in sidewalk astronomy.

corporate arena for only a year.

in 1944, dobson joined the city’s Vedanta Society monastery. there, he spent 23 years as a monk of the ramakrishna order. he saw one of his tasks as reconciling astronomy with the society’s teachings.

dobson built his first telescope — a 2-inch refractor — in 1956. he used a lens he purchased in a junk store and an eyepiece from old binoculars. through it he saw the rings of Saturn.

one of his fellow monks mentioned that it was possible to grind a mirror and construct a reflecting telescope. dobson quickly made his first mirror out of a 12-inch piece of porthole glass from a marine salvage yard. when he looked at the Last Quarter Moon through his finished scope, he was surprised and deeply moved by what he saw. his first thought was, “everybody’s got to see this.”

in 1958, the order transferred dobson to the monastery in Sacramento. he made numerous telescopes there, the first being a 5-inch reflector.

he left the monastery in 1967, hitch-hiked back to San Francisco, and co-founded the SFSa the next year with two of his students, bruce Sams and Jeff roloff. in lieu of formal

it’s a sad moment for amateur astronomy. the San Francisco Sidewalk astronomers (SFSa) reported yesterday the passing of

John dobson. he died peacefully wednesday morning, January 15, in burbank, California. he was 98. he leaves behind a son, numerous close friends, and fans and admirers worldwide.

dobson is best known for inventing a revolutionary mount for reflecting telescopes. now known as the dobsonian mount, it is an altitude-azimuth assembly that is both simple and inexpensive to build. and although he also taught telescope making — including how to grind and polish mirrors — the benchmark moment came when he devised the mount.

during the past four decades, uncounted thousands of observers have dobson to thank for letting them enjoy views of the heavens through larger (and often much larger) telescopes than they could have afforded prior to his invention.

dobson was born September 14, 1915, in beijing, China, where his maternal grandfather had founded peking university in 1898. the family moved to San Francisco in 1927.

dobson graduated from the university of California, berkeley, with a master’s degree in chemistry. afterward, he worked in the

John Dobson revolutionized amatuer astronomy. He passed away January 15, 2014, at age 98. (Credit: Richard Berry)

John Dobson was always willing to help a fellow amateur astronomer. He was an expert in grinding mirrors and making tele-scopes and mounts. Image: Jim Baumgardt

membership meetings, club members would set up telescopes on the city sidewalk for passers-by to view the heavens and learn more about astronomy.

over time, original members of the group left the area and founded other astronomy clubs throughout the united States. and although the original chapter and some newer ones have kept their city designations, the group renamed itself the Sidewalk astronomers in 1976. you can visit the organization’s website at www.sidewalkastronomers.us.

on March 8, in honour of dobson, the Sidewalk astronomers will dedicate this year’s international Sidewalk astronomy night to his memory. amateur astronomers around the globe can join in and celebrate dobson’s life and continue to carry the torch that he lit back in 1968.

3www.astroNoMy.org.Nz

PO Box 24187, Roya l Oak, Auck land 1345, New Zea land • www.ast ronomy.org .nz

Notice of Annual General Meeting

The Annual General Meeting of the Auckland Astronomical Society Inc. will be held in the Sun Room of the Stardome Observatory, One Tree Hill Domain on Monday 28nd April 2014 starting at 8:00pm.

All society members are encouraged to attend and help with the future of the Society.

The agenda and a copy of the reports will be posted on the member’s area of the society website (www.astronomy.org.nz) at least one week before the meeting. Printed copies will also be distributed at the meeting.

Nominations are open for all council positions; President, Vice President, Treasurer, Secretary, Librarian, Curator of Instruments, Editor and three to Þve council members. Nominations must be received by the Secretary by Monday 7th April 2014 and must be made using the form below. Note nominees, nominators and seconders must be current Þnancial members.

Any questions or enquires can be directed to Grant Christie (President) by email to [email protected] or phone 09 636 3437.

NOMINATION FOR AUCKLAND ASTRONOMICAL SOCIETY COUNCIL

To be completed by the nominator & a seconder. Both must be a current Þnancial member.

!I nominate .................................................................... .............................................................................

for the position of ................................................................................

signed: dated: ...................................................... .........

I second the nomination of .................................................................... .............................................................

for the position of ................................................................................

signed: dated: ...................................................... .........

To be completed by the nominee. The nominee must be a current financial member and have been so for at least one year.

!I accept nomination for .................................................................... ........................................................

signed: dated: ...................................................... .........

SEND FORM TO: The Secretary, Auckland Astronomical SocietyPO Box 24187, Royal Oak, Auckland 1345

Must be received by 7th April 2014.


Mapping the Milky Way’s Armsby Kelly Beatty, Sky and Telescope

Artist’s concept of the Milky Way’s structure, with only two major arms, based on Spitzer Space Telescope data. NASA / JPL-Caltech / R. Hurt


Using a 12-year survey of massive stars, a research team concludes that four major arms, not two, are wrapped around our home galaxy’s central bar.

two arms, or two more

arms — that is the question.

with apologies to prince hamlet,

astronomers can’t agree on whether the

Milky way boasts two dominant spiral

arms (and some smaller appendages)

or four of them. the evidence is murky,

because observers are deducing details

of the spiral shape from within the disk.

everyone agrees that our galaxy has an

elongated central region — a fat bar

crowded with stars — that’s several

thousand light-year long, though its true

length is a matter of debate. and they

agree that two big arcs of stars spiral out

from the bar’s ends: the perseus arm and

Scutum-Centaurus arm. these names

correspond to the constellations in which

the arms are tangent to our line of sight,

creating an apparent pileup of stars.

Several decades ago, radio-wavelength observations suggested the existence of two other major appendages dubbed the Sagittarius and norma arms. but by 2008, astronomers had a potent new observational tool: the Spitzer Space telescope. its detailed infrared survey of the galactic plane, involving 800,000 images recording more than 110 million stars, confirmed the perseus and Scutum-Centaurus arms. but strong evidence for the other two arms was absent, leading robert benjamin (university of wisconsin) and others to conclude that they’d “gone missing” and were probably just minor appendages like the orion Spur, on which our Sun lies. not everyone accepted the Spitzer-based result, however. other researchers, led by thomas Steiman-Cameron (indiana university), mapped pockets of interstellar gas using far-infrared observations from the Cosmic background explorer (Cobe) satellite. their results backed the four-arc model. now a new shot has been fired in the Great arm war. James urquhart (Max planck institute for radio astronomy) and others have analysed 12 years of observations

collected by radio telescopes in australia, the united States, and China that determined the distance and brightness of massive stars just emerging from their natal cocoons of gas and dust. these stars, each with at least eight times the Sun’s mass and 10,000 times its luminosity, last only about 10 million years. So they don’t survive long enough to meander to new locations as they orbit the galactic centre. (our Sun, for example, has already circled around 10 times during its 4½-billion-year existence.) in January 11th’s Monthly notices of the royal astronomical Society, urquhart’s team reports that a 3-d map of 1,650 such massive stars clearly delineates all four spiral arms. in fact, the Sagittarius arm stands out in the new survey more prominently than the better-known perseus arm does. the new result appeared online last week. “it isn’t a case of our results being right and those from Spitzer’s data being wrong,” comments co-author Melvin hoare (university of Leeds) in a press release. “Spitzer only sees much cooler, lower-mass stars - stars like our Sun - which are much more numerous than the massive stars that we were targeting.”

A new survey of young, massive stars (red dots) throughout our galaxy reveals that the Milky Way has four prominent arms after all — not just two (Perseus and Scutum-Centaurus), as earlier observations had suggested. No observations were made in the gray area, due to confusion with the galactic center.J. Urquhart / MNRAS; background: NASA / JPL / R. Hurt


MARCH PROGRAMME

Mon 3 7:00pm

8:00pm

astrophotography Group

practical astronomy with bill thomas

Fri 7 7:30 pm young astronomers with Margaret arthur

Mon 9 8:00pm Monthly meetingSubject tba

Mon 17 8:00pm intro to astronomy with bernie brenner

Mon 24 8:00pm Film night march

Can we make it to Mars

FEBRUARY PROGRAMME

wed 5 7:30pm young astronomers with Margaret arthur

Mon 3 8:00pm practical astronomy Feb - telescopes and Mountsbill thomas

Mon 24 8:00pm Special General Meeting

Mon 10 8:00pm February Monthly Meeting - dr. eliot Quataert, Video Lecture“how the universe went from Smooth to Lumpy: the Modern origins Story”

Mon 17 8:00pm intro to astronomy with bernie brenner

Mon 24 8:00pm Special General Meeting

Film night February - Seven ages of Starlight

Calendar and Events

FilM NiGHt FEBRUARYMonday 24th February at 8:00pm

with Gavin Logan

a documentary showing how stars are created, age and eventually die. it covers the different types of stars and discusses what makes them different in terms of lifespan, chemical composition, size, density and luminance.

WElCOME NEW MEMBERs

Lisa Currie (ordinary)brian wheeler (family)Vishnu Seger (ordinary)aubrey Symons (country)Justin LeGrice (ordinary)Michael Liew (ordinary)Clint baker (family)Christie walker (ordinary)kirsty Glassborow (family)Garry Sheeran (ordinary)tate pichon (youth)Manya Craig (family)Chris Cumming (ordinary)James Stone (family)nicholas o’Flaherty (family)Grant eades (ordinary)

sPECiAl GENERAl MEEtiNG Monday 24 February, 2014 at 8:00pmVenue: stardome

a Special General Meeting has been called to consider the below motion. it will be held at the start of the Film night

astronomy nZ Ltd (astronz) is a company fully owned by the auckland astronomical Society selling telescopes and accessories to the new Zealand market.

astronz is planning on expanding its product range in 2014 and is seeking to borrow funds from the Society to use as working capital to fund the purchase of stock. due to the amount (up to $30,000) it is being referred to membership for approval.

the SGM is being called to consider the motion:

“that the Society loan astronomy nZ Ltd up to $30,000 to be used as working capital to fund the purchase of stock”.

the directors of astronz will be at the meeting to answer any questions.

2014 PROGRAMME

there have been some changes to our standard program-me this year. For 2014 the regular schedule will be:First Monday practical astronomya club night based on learning the night sky and using your telescopeFirst Friday young astronomersaimed at the younger members of the Society. Suitable for age 7 years and up.Second Monday Monthly Meetingnormally is a talk by a guest speaker.third Monday introduction to astronomyan introductory astronomy course covering different topics throughout the year.Fourth Monday Film nightwe screen a range of astronomy and science documentaries

please check the journal or aaS website for the latest upates and programme changes


December’s Great Mars Debate.AAS December monthly meeting

by Oana Jones

december’s monthly meeting

hosted the aaS Great Mars

debate, a 3-a-side discussion

about Mars colonisation and migration.

after a workshop with Mary Marshall,

an international speech champion and

seasoned debator, the teams of debating

volunteers only had a week to formulate

their arguments and prepare.

the room was packed, with a fantastic

turnout for a december meeting so close

to everyone’s holiday breaks, and the mood

was festive and excited. while there were

many familiar faces, we were also lucky

enough to meet some members that made

the trip especially for the debate.

Gavin Logan, Carol Varughese and paul

Jones did a fantastic job of shoring up the

affirmative team against the onslaught

of david britten, Steve hennerley and

niven brown on the negative team.

while the affirmative team tantalised

everyone with forward-thinking ideas and

creative problem solving to some of Mars

colonisation’s greatest issues, the negative

team brought the room back down to

earth by exposing the harsh realities of the

situation, which they summed up neatly

in their team’s main point; if you move to

Mars, you’ll die.

everyone got involved, with points, jokes

and arguments flowing freely from the

audience in favour of both teams. Grant

Christie was kind enough to chair the

debate and had several witty retorts of his

own to add to the discussion.

despite a fantastic offence by the negative

team, the affirmative team took out the

victory, proving that a room of hopeful

amateur astronomers are excited and

eager for the next step in human space

flight, and both teams received a roaring

round of applause.

the debate however was not really at

an end, spilling over to smaller group

discussions during supper and then well

into the night. it was a fantastic evening full

of facts, quips and fun and it couldn’t have

happened without everyone’s boundless

enthusiasm.

if you missed the debate, or want to watch

it again and pore over the details, a dVd

will be available in the library towards the

end of February.

thank you to everyone, and especially our

wonderful volunteer debaters.

Training Sessions

we will be conducting telescope training sessions at 7pm on the 1st and 3rd Mondays before the ‘intro to astronomy’ and ‘practical astronomy’ sessions. this will enable members to:

• Learn to use the Society rental equipment. note there are a number of new items being added to the rental range.

• bring along your own telescope for lesson on how to best use it.

• Learn to use the large ewb telescope at Stardome.

For more information, please contact andrew buckingham or Steve hennerley.

Gavin Logan makes his point at the Mars Debate

Steve Hennerley keeps the debate grounded for the negative team


Library Corner by Tony Reynolds, Auckland Astronomical Society

Featured Section – QB35 Biographies

our collection of biographies of astronomers includes tycho, kepler, Galileo, herschel, payne-Gaposchkin, Moore and more. if you aren’t familiar

with any of these names you should be! Get in here and before long you’ll be dropping names around the society like a pro.

we also have a number of biographies of physicists in our physics section - QC, in particular newton and einstein.

regards

tony reynolds

Overdue Notices

Some of you may have received an overdue notice where our records show outstanding items. our records are a bit out of date so if you believe

this an error, simply reply to the email stating as much as i will correct the records. if you do have an overdue item, or you find an item you thought

you’d returned, just drop it in the returns box in the library.

New Books - The following titles have been recently added to the library.

Europe to the Stars

Govert SchillingSumptuously illustrated coffee-table book taking the reader behind the scenes at the most productive ground-based observatory of the world. Contains the best 300 hand-picked images from eSo’s large collection of more than 100,000 images. produced especially for eSo’s 50th anniversary.

Catalogue section: Qb81

Lessons from the Masters: Current Concepts in Astronomical Image Processing

Robert GendlerCatalogue section: Qb

Hubble’s Universe: Greatest Discoveries and Latest Images

Terence Dickinson no other telescope combines instant name recognition with the production of consistently spectacular images. yet few people outside of the astronomy community realize that hubble is now at the apex of its imaging capabilities.

a collection of stunningly detailed pictures, made possible by the new wide Field Camera 3.

Catalogue section: Qb


Slide off roof observatory for sale

needs to be removed from site.

it is screwed together so can be taken apart, removed in pieces and reassembled at a new site. 2.7 metres by 2.7 metres in size it is made from a modified garden shed. Selling it because i am selling my house and the townhouse i am moving to does not have a suitable site for it. works well. has polystyrene lining to minimise moisture.

open to all reasonable offers.

phone Gavin Logan on (09) 820 6001 or 021 144 1055 for more detail or inspection. email: [email protected]

sOCiEtY COUNCil ANd OFFiCERs

president Grant Christie 021 024 04992Vice-president bill thomas 09 478 4874treasurer & andrew buckingham 09 473 5877MembershipSecretary kleo Zois 022 691 2055Curator of Graham beazley 09 537 1313instrumentsLibrarian tony reynolds 09 480 8607 telescope hire Steve hennerley 0027 245 644 Journal editors Clive bolt 09 534 2946 Shaun Fletcher 09 480 5648 Milina ristić 029 912 4748 Council bernie brenner 09 534 4103 Gavin Logan 09 820 6001 david britten 09 846 3657 oana Jones 021 236 2962

sOCiEtY CONtACts

auckland astronomical Society inc, po box 24187, royal oak, auckland 1345, new Zealand

email [email protected] [email protected] www.astronomy.org.nzFacebook facebook.com/auckastroSoctwitter @auckastroSoc

Membership enquiries:contact andrew buckingham at [email protected] or by phone on 09 473 5877 or 027 246 2446


Giant Sunspot, Larger Than Earth’s Diameter, Appears On Sunby Science Daily

an enormous sunspot, labelled ar1944, slipped into view over the Sun’s left horizon late on

Jan. 1, 2014. the sunspot steadily moved

toward the right, along with the rotation

of the Sun, and now sits almost dead

centre, as seen in the image above from

naSa’s Solar dynamics observatory.

Sunspots are dark areas on the

Sun’s surface that contain complex

arrangements of strong magnetic

fields that are constantly shifting. the

largest dark spot in this configuration

is approximately two earths wide, and

the entire sunspot group is some seven

earths across. For comparison, another

giant sunspot, five to six earths across, is shown below from 2005.

the image was captured by the european Space agency and naSa’s Solar and heliospheric observatory. Sunspots are part of what’s known as active regions, which also include regions of the Sun’s atmosphere, the corona, hovering above the sunspots.

active regions can be the source of some of the sun’s great explosions: solar flares that send out giant bursts of light and radiation due to the release of magnetic energy, or coronal mass ejections that send huge clouds of solar material out into space. as the sunspot group

One of the largest sunspots in the last nine years, labelled AR1944, was seen in early January 2014, as captured by NASA’s Solar Dynam-ics Observatory. An image of Earth has been added for scale. (Credit: NASA/SDO)

continues its journey across the face of the Sun, scientists will watch how it changes and evolves to learn more about how these convoluted magnetic fields can cause space weather events that can affect space-borne systems and technological infrastructure on earth.


Mission to MarsFilm Night December - by Gavin Logan

Astronauts on the surface of Mars in the science fiction film “Mission to Mars”

A very good audience at the pre-Christmas science fiction film night.

december’s film night was surprisingly well attended considering it was held two days

before Christmas. Society members who attended had a choice of four science fiction movies. based on an audience vote a film that no one attending had seen was chosen. it was a film made for american tV called “Mission to Mars”.

in many ways the film was the complete space flight enthusiast’s fantasy. it covered a futuristic manned mission to Mars in which a survivor of an earlier mission that had gone wrong was found along with the story of what had happened to a human civilisation that had disappeared from Mars. the survivor had created his own insulated Mars habitat. it combined all the elements of love, romance, death and high drama to make compelling viewing. a complete array of futuristic type exploring equipment along with a Mars orbiter was shown in the film. although relatively far-fetched the audience was treated to an entertaining film that at least had some semblance of scientific plausibility. refreshments

and a light supper including cinema type popcorn were also enjoyed by attendees.

the first film night of 2014 is on Monday 24th February at 8 pM at Stardome. it features a film called “Seven ages of Starlight” which goes through the different types of stars, showing how stars are created, age and eventually die.

it covers the different types of stars and discusses what makes them different in terms of lifespan, chemical composition, size, density and luminance For Mars travel enthusiasts March’s film night will feature documentary that gives some real facts on the feasibility of a manned Mars mission.


First Radiation Measurements from the Surface of Marsby Science Daily

in the first 300 days of the Mars Science Laboratory surface mission, the Curiosity rover cruised around

the planet’s Gale Crater, collecting soil

samples and investigating rock structures

while the on board radiation assessment

detector made detailed measurements of

the radiation environment on the surface

of Mars.

Swri scientists published radiation

surface dose rates from the first 300

days on Mars in Science online dec. 9.

Curiosity’s radiation assessment detector

observed a spike in the radiation dose

associated with one hard solar energetic

particle event and three dips in radiation

associated with soft interplanetary

coronal mass ejections, which provided

magnetic shielding against galactic cosmic

rays. occasional brief gaps are typically

when rad was powered off to minimize

interference with other activities.

“our measurements provide crucial

information for human missions to

Mars,” said dr. don hassler, a Southwest

research institute program director

and rad principal investigator. hassler

is the lead author of “Mars’ Surface

radiation environment Measured with

the Mars Science Laboratory’s Curiosity

rover,” scheduled for publication in the

journal Science online on december 9,

2013. “we’re continuing to monitor the radiation environment, and seeing the effects of major solar storms on the surface and at different times in the solar cycle will give additional important data. our measurements also tie into Curiosity’s investigations about habitability. the radiation sources that are of concern for human health also affect microbial survival as well as the preservation of organic chemicals.”

two forms of radiation pose potential health risks to astronauts: a chronic low dose of galactic cosmic rays (GCrs) and the possibility of short-term exposures to the solar energetic particles (Seps) associated with solar flares and coronal mass ejections. the radiation on Mars is much harsher than on earth for two reasons: Mars lacks a global magnetic field and the Martian atmosphere is much thinner than earth’s, providing little shielding to the surface.

this environmental factor poses a challenge for future human exploration of Mars and is also important in understanding both geological and potential biological evolution on Mars. both GCrs and Seps interact with the atmosphere and, if energetic enough, penetrate into the Martian soil, or regolith, where they produce secondary particles that contribute to the complex radiation environment on the Martian surface, which is unlike anything on earth.

“the rad surface radiation data show an average GCr dose equivalent rate of 0.67 millisieverts per day from august 2012 to June 2013 on the Martian surface,” said hassler. radiation dose is measured in units of sievert (Sv) or millisievert (1/1000 Sv). “in comparison, rad data show an average GCr dose equivalent rate of 1.8 millisieverts per day on the journey to Mars, when rad measured the radiation inside the spaceship.”

using the data collected by Swri’s radiation assessment detector on board the Curiosity rover, this chart compares the radiation dose equivalent for a 500-

Using the data collected by SwRI’s Radiation Assessment Detector onboard the Curiosity rover, this chart compares the radiation dose equivalent for a 500-day stay on Mars to the dose associated with a 180-day journey to Mars, a six-month stay on the International Space Station and several Earth-based sources of radiation. (Credit: Image courtesy of Southwest Research Institute)


day stay on Mars to the dose associated with a 180-day journey to Mars, a six-month stay on the international Space Station and several earth-based sources of radiation.

according to rad data, most mission radiation exposure will be during outbound and return travel, when the astronauts will be exposed to the radiation environment in interplanetary space, shielded only by the spacecraft itself. the total during just the transit phases of a Mars mission would be approximately 0.66 Sv for a round trip with current propulsion systems and during similar solar activity. a 500-day mission on the surface would bring the total exposure to around 1 Sv.

Long-term population studies have shown that exposure to radiation increases a

person’s lifetime cancer risk; exposure to a dose of 1 Sv is associated with a five percent increase in fatal cancer risk. although naSa has generally established a three percent increased risk of fatal cancer as an acceptable career limit for astronauts in low earth orbit, it does not currently have a limit for deep space missions, and is working with the national academies institute of Medicine to determine appropriate limits for deep space missions, such as a mission to Mars in the 2030s.

Swri, together with Christian albrechts university in kiel, Germany, built rad with funding from the naSa human exploration and operations Mission directorate and Germany’s national aerospace research centre, deutsches Zentrum für Luft- und raumfahrt.

naSa’s Jet propulsion Laboratory, a division of the California institute of technology, pasadena, Calif., manages the Mars Science Laboratory project. the naSa Science Mission directorate, at naSa headquarters in washington, manages the Mars exploration program.

2014 NZ Astronomical Yearbook

the 2014 edition of the nZ astronomical yearbook is now available.

published by Stardome observatory it is a great resource on current events and what is happening in 2014.

as well as monthly sky guides and star charts, it includes articles on:

• Supernova hunter Stuart parker

• the Chelyabinsk Meteor

• astrophotographers Mark Gee & rolf olsen

• Colonising Mars & Getting a Closer Look at the red planet

• how will we Find earth-Like planets?

• the origin of earth’s water

• eclipses in 2014

• Meteor Showers for 2014

• Sunrise / Sunset and Moonrise / Moonset information for 2014

the book is full of spectacular images from new Zealand astrophotographers.

aaS members can order directly from the Society at the discounted price of $14.00 (normally $20.00) + $2.50 postage

the 2014 yearbook will be available at any aaS meeting or can be ordered from andrew buckingham at [email protected] or phone 09 473 5877


The Evening Sky in February 2014By Alan Gilmore, University of Canterbury‘s Mt John Observatory, www.canterbury.ac.nz

Jupiter is the ‘evening star’, appearing in the north soon after sunset. well above it is Sirius, the brightest true star. Continuing the arc south of overhead finds Canopus, the second brightest star.

Jupiter shines with a steady golden light. a telescope will easily show the four bright moons first seen by Galileo in 1610. binoc-ulars, steadily held, often show one or two moons looking like faint stars very close to the planet. Jupiter is 670 million km from us

now. the planet is 11 times earth’s diame-ter and 320 times earth’s mass. it sets in the northwest in the morning hours.

Sirius, ‘the dog Star’, marks the head of Canis Major the big dog. a group of stars above and right of it make the dog’s hind-quarters and tail. procyon, in the northeast below Sirius, marks the smaller of the two dogs that follow orion the hunter across the sky. Sirius is eight light years* away.

below and left of Sirius are bluish rigel and orange betelgeuse, the brightest stars in orion. between them is a line of three stars: orion’s belt. to southern hemisphere star watchers, the line of three makes the bottom of ‘the pot’. the handle of the pot is orion’s sword, a fainter line of stars above the bright three. at its centre is the orion nebula; a glowing gas cloud around 1300 light years away.

orion’s belt points down and left to the or-


ange star aldebaran. Continuing the line finds the pleiades or Matariki star cluster. aldebaran is arabic for ‘the eye of the bull’. it is on one tip of an upside-down V that makes the face of taurus. the V-shaped group is called the hyades cluster. it is 130 light years away. aldebaran is not a mem-ber of the cluster but merely on the line of sight, 65 light years from us. it is 145 times brighter than the sun. the pleiades or Matariki star cluster is also known as the Seven Sisters and Subaru. Six stars are seen by eye; dozens are visible in binoculars. the cluster is 400 light years from us. its stars formed around 100 million years ago. From northern new Zealand the bright star Capella is on the north skyline. it is 90,000 times brighter than the sun and 3300 light years away.

Crux, the Southern Cross, is in the south-east. below it are beta and alpha Centauri, often called ‘the pointers’. alpha Centauri is the closest naked-eye star, 4.3 light years away. beta Centauri, like most of the stars

in Crux, is a blue-giant star hundreds of light years away. Canopus is also a very lu-minous distant star; 13 000 times brighter than the sun and 300 light years away.

the Milky way is brightest in the southeast toward Crux. it can be traced up the sky, fading where it is nearly overhead. it be-comes very faint east or right of orion. the Milky way is our edgewise view of the gal-axy, the pancake of billions of stars of which the sun is just one.

the Clouds of Magellan, LMC and SMC are high in the south sky, easily seen by eye on a dark moonless night. they are two small galaxies about 160 000 and 200 000 light years away.

Mars (not shown on the chart) rises a little south of due east about 11 pm mid month, a bright orange-red ‘star’ below fainter blue-white Spica. Mars is brightening as we catch it up. it will be 140 million km away mid month. it is small in a telescope but it

will be only half as big again when we pass it by in april.

Saturn (not shown) rises in the southeast around midnight mid month. it is a little fainter than Mars and has a creamy colour. well to its right is orange antares, marking the Scorpion’s heart. Saturn is 1460 million km away mid month. it is always worth a look in a telescope.

Venus (not shown) rises in the south-east about 4:30 a.m. at the beginning of the month; 3:40 by the 28th. it is bright enough to cast shadows in dark locations. it is 60 million km away mid month, looking like a tiny crescent moon in a telescope. it is leaving us behind as it moves to the far side of the sun.

Mercury (not shown) begins a morning sky appearance in the last week of February, ris-ing nearly two hours before the sun, below and right of Venus. it appears very small in a telescope.

Fast Radio Bursts Might Come from Nearby Starsby Science Daily

First discovered in 2007, “fast radio bursts” continue to defy explanation. these cosmic chirps last for only a

thousandth of a second. the characteristics of the radio pulses suggested that they came from galaxies billions of light-years away. however, new work points to a much closer origin - flaring stars within our own galaxy.

“we propose that fast radio bursts aren’t as exotic as astronomers first thought,” says lead author avi Loeb of the harvard-Smithsonian Center for astrophysics (Cfa).

Fast radio bursts are both brief and bright, packing a lot of energy into a short time. only six have been discovered to date, all of them in archival data. each was detected only once, making follow-up studies difficult.

a detailed analysis of the bursts showed that the pulses passed through a large column of electrons on their way to earth. if those electrons were spread out across intergalactic space, then the pulses must have crossed billions of light-years. as a result, they would have to come from extremely energetic events. Gamma-ray bursts don’t produce the right radio frequencies, so astronomers looked to other extreme events like the collapse of a neutron star into a black hole.

Loeb and his colleagues reasoned that if the bursts came from a closer location, within the Milky way galaxy, then they wouldn’t require as much energy. the explanation could be more mundane.

Stellar flares fit the bill. tightly packed electrons in the stellar corona would cause the same effect as the more diffuse intergalactic electrons.

two types of stars are known to create radio bursts: young, low mass stars and solar-mass “contact” binaries which orbit so close that they share their outer, gaseous envelopes. both types of star system would also fluctuate in brightness at optical wavelengths (i.e. visible light).

to test their theory Loeb and his colleagues searched the locations of three fast radio bursts to look for variable stars, using the telescopes at tel-aviv university’s wise observatory, in israel. “it was straightforward to monitor these fields for several nights, to see if they showed anything unusual,” says dani Maoz of tel aviv university.

“we were surprised that, apparently, no one had done this before,” adds yossi Shvartzvald, a graduate student who led the observations.

they discovered a contact binary system in one location. the binary consists of two Sun-like stars orbiting each other every 7.8 hours. they are located about 2,600 light-years from earth. Statistics of stars across the observed field of view show that there is less than a 5 percent chance that the binary star is in the right place by coincidence.

“whenever we find a new class of sources, we debate whether they are close or far away,” says Loeb. Gamma-ray bursts were initially thought to be coming from within the Milky way; only later did astronomers learn they came from cosmological distances. ”here we have exactly the opposite,” explains Loeb. Fast radio bursts, initially thought to be distant, may actually originate from our own galaxy.

New research suggests that mysterious events known as fast radio bursts might come from nearby flaring stars, rather than more energetic events in the distant universe. This image of the Sun, from NASA’s Solar Dynamics Observatory, shows a lower-energy exam-ple of the kind of event that could cause fast radio bursts.


NASA‘s Cassini Spacecraft Obtains Best Views of Saturn Hexagon from Science DailynaSa’s Cassini spacecraft has obtained the highest-resolution movie yet of a unique six-sided jet stream, known as the hexagon, around Saturn’s north pole.

this is the first hexagon movie of its kind, using colour filters, and the first to show a complete view of the top of Saturn down to about 70 degrees latitude. Spanning about 30,000 kilometres across, the hexagon is a wavy jet stream of 322 kilometres per hour winds with a massive, rotating storm at the centre. there is no weather feature exactly, consistently like this anywhere else in the Solar System.

“the hexagon is just a current of air, and weather features out there that share similarities to this are notoriously turbulent and unstable,” said andrew ingersoll, a Cassini imaging team member at the California institute of technology in pasadena. “a hurricane on earth typically lasts a week, but this has been here for decades - and who knows - maybe centuries.”

weather patterns on earth are interrupted when they encounter friction from landforms or ice caps. Scientists suspect the stability of the hexagon has something to do with the lack of solid landforms on Saturn, which is essentially a giant ball of gas.

better views of the hexagon are available now because the Sun began to illuminate its interior in late 2012. Cassini captured images of the hexagon over a 10-hour time span with high-resolution cameras, giving scientists a good look at the motion of cloud structures within.

they saw the storm around the pole, as well as small vortices rotating in the opposite direction of the hexagon. Some of the vortices are swept along with the jet stream as if on a racetrack. the largest of these vortices spans about 3,500 kilometres, or about twice the size of the largest hurricane recorded on earth.

Scientists analysed these images in false colour, a rendering method that makes it easier to distinguish differences among the types of particles suspended in the atmosphere - relatively small particles that make up haze - inside and outside the hexagon.

“inside the hexagon, there are fewer large haze particles and a concentration of small haze particles, while outside the hexagon, the opposite is true,” said kunio Sayanagi, a Cassini imaging team associate at hampton university in Virginia. “the hexagonal jet stream is acting like a barrier, which results in something like earth’s antarctic ozone hole.”

the antarctic ozone hole forms within a region enclosed by a jet stream with similarities to the hexagon. wintertime conditions enable ozone-destroying chemical processes to occur, and the jet stream prevents a resupply of ozone from the outside. at Saturn, large aerosols cannot cross into the hexagonal jet stream from outside and large aerosol particles are created when sunlight shines on the atmosphere. only recently, with the start of Saturn’s northern spring in august 2009, did sunlight begin bathing the planet’s northern hemisphere.

“as we approach Saturn’s summer solstice in 2017, lighting conditions over its north pole will improve, and we are excited to track the changes that occur both inside and outside the hexagon boundary,” said Scott edgington, Cassini deputy project scientist at naSa’s Jet propulsion Laboratory in pasadena, Calif.

a black-and-white version of the imaging camera movie and movies obtained by Cassini’s visual and infrared mapping spectrometer are also tools Cassini scientists can use to look at wind speeds and the mini-storms inside the jet stream.

Cassini launched in 1997 and arrived at Saturn on July 1, 2004. its mission is scheduled to end in September 2017. the Cassini-huygens mission is a cooperative project of naSa, the european Space agency and the italian Space agency. JpL manages the mission for naSa’s Science Mission directorate in washington. JpL designed, developed and assembled the Cassini orbiter and its two on-board cameras. the imaging team is based at the Space Science institute, boulder, Colo.

This colourful view from NASA’s Cassini mission is the high-est-resolution view of the unique six-sided jet stream at Saturn’s north pole known as “the hexagon.” This movie, made from images obtained by Cassini’s imaging cameras, is the first to show the hexagon in colour filters, and the first movie to show a complete view from the north pole down to about 70 degrees north latitude. (Credit: NASA/JPL-Caltech/SSI/Hampton)


Gemini Planet Imager’s first light image of the light scattered by a disk of dust orbiting the young star HR4796A. This narrow ring is thought to be dust from asteroids or comets left behind by planet formation; some scientists have theorized that the sharp edge of the ring is defined by an unseen planet. The left image shows normal light, including both the dust ring and the residual light from the central star scattered by turbulence in the Earth’s atmosphere. The right image shows only polarized light. Leftover starlight is unpolarized and hence removed from this image. The light from the back edge of the disk is strongly polarized as it scatters towards us. (Credit: Image courtesy of DOE/Law-rence Livermore National Laboratory)

Out-Of-This-World First Light Images Emerge from Gemini Planet Imager from Science dailyafter nearly a decade of development, construction and testing, the world’s most advanced instrument for directly imaging and analysing planets orbiting around other stars is pointing skyward and collecting light from distant worlds.

“even these early first-light images are almost a factor of 10 better than the previous generation of instruments. in one minute, we were seeing planets that used to take us an hour to detect,” says bruce Macintosh of Lawrence Livermore national Laboratory, who led the team who built the instrument.

For the past decade, Lawrence Livermore has been leading a multi-institutional team in the design, engineering, building and optimization of the instrument, called the Gemini planet imager (Gpi), which will be used for high-contrast imaging to better study faint planets or dusty disks next to bright stars. astronomers - including a team at LLnL- have made direct images of a handful of extrasolar planets by adapting astronomical cameras built for other purposes. Gpi is the first fully optimized planet imager, designed from the ground up for exoplanet imaging deployed on one of the world’s biggest telescopes, the 8-metre Gemini South telescope in Chile.

probing the environments of distant stars in a search for planets has required the development of next-generation, high-contrast adaptive optics (ao) systems, in which Livermore is a leader. these systems are sometimes referred to as extreme ao.

Macintosh said direct imaging of planets is challenging because planets such as Jupiter are a billion times fainter than their parent stars. “detection of the youngest and brightest planets is barely within reach of today’s ao systems,” he said. “to see other solar systems, we need new tools.”

and those new tools are installed in the Gemini planet imager with the most advanced ao system in the world. in addition to leading the whole project, LLnL also was responsible for the ao system. designed to be the world’s “most sophisticated” astronomical system for compensating turbulence in the earth’s atmosphere - an ongoing problem for ground-based telescopes - the system senses atmospheric turbulence and corrects it with a 2-centimetre-square deformable mirror with 4,000 actuators. this deformable mirror is made of etched silicon, similar to microchips, rather than the large reflective glass mirrors used on other ao systems. this allows Gpi to

be compact and stable. the new mirror corrects for atmospheric distortions by adjusting its shape 1,000 times per second with accuracy better than 1 nanometre. together with the other parts of Gpi, astronomers can directly image extra-solar planets that are 1 million to 10 million times fainter than their host stars.

Gpi carried out its first observations in november 2013 - during an extremely smooth debut for an extraordinarily complex astronomical instrument the size of a small car. “the Gpi team’s huge amount of high quality work has begun to pay off and now holds the promise of many years of important science to come,” said LLnL project Manager david palmer.

For Gpi’s first observations, it targeted previously known planetary systems - the 4-planet hr8799 system (co-discovered by an LLnL-led team at the Gemini and keck observatory in 2008) and the beta pictoris system, among others. Gpi has obtained the first-ever spectrum of the very young planet beta pictoris b.

the first-light team also used the instrument’s unique polarization mode - tuned to look at starlight scattered by tiny particles - in order to study a ring of dust orbiting the very young star hr4796. with previous instruments, only the edges of this dust ring (which may be the debris remaining from planet formation) could be seen. Gpi can follow the entire circumference of the ring. the images were released today at the

223rd meeting of the american astronomical Society in washington d.C., Jan. 5-9.

“Gpi’s performance requirements are extremely challenging,” explained LLnL engineer Lisa poyneer, who developed the algorithms used to correct for atmospheric turbulence, and led the testing of the adaptive optics system in the laboratory and at the telescope. “as a result, the ao system features several original technologies that were designed specifically for exoplanet science. after years of development and testing, it is very rewarding to see the ao system operating so well and enabling these remarkable images.”

imaging exoplanets is highly complementary to other exoplanet success stories like naSa’s kepler mission. kepler is extremely sensitive to small planets close to their parent star and focuses on mature stars - Gpi detects infrared radiation from young Jupiter-like objects in wide orbits, the equivalent of the giant planets in our Solar System not long after their formation.

“Gpi represents a critical step in the road toward understanding how planetary systems form and develop,” said dmitry Savransky, an LLnL postdoc who worked on the integration and testing of Gpi before moving to a position at Cornell. “while broad survey missions, such as kepler, have revealed the variety of planets that exist in our galaxy, Gpi will allow us to study a few dozen planets in exquisite detail.”


You Can’t Get Entangled Without a Wormhole: Physicist Finds Entanglement Instantly Gives Rise to a Wormholefrom Science daily

Quantum entanglement is one of the more bizarre theories to come out of the study of quantum me-

chanics - so strange, in fact, that albert einstein famously referred to it as “spooky action at a distance.”

essentially, entanglement involves two par-ticles, each occupying multiple states at once - a condition referred to as superposi-tion. For example, both particles may simul-taneously spin clockwise and counter clock-wise. but neither has a definite state until one is measured, causing the other particle to instantly assume a corresponding state. the resulting correlations between the par-

ticles are preserved, even if they reside on opposite ends of the universe.

but what enables particles to communi-cate instantaneously - and seemingly fast-er than the speed of light - over such vast distances? earlier this year, physicists pro-posed an answer in the form of “worm-holes,” or gravitational tunnels. the group showed that by creating two entangled black holes, then pulling them apart, they formed a wormhole - essentially a “short-cut” through the universe - connecting the distant black holes.

now an Mit physicist has found that, looked at through the lens of string theory,

the creation of two entangled quarks - the building blocks of matter - simultaneously gives rise to a wormhole connecting the pair.

the theoretical results bolster the relatively new and exciting idea that the laws of grav-ity holding together the universe may not be fundamental, but arise from something else: quantum entanglement.

Julian Sonner, a senior postdoc in Mit’s Laboratory for nuclear Science and Center for theoretical physics, has published his re-sults in the journal physical review Letters, where it appears together with a related paper by kristan Jensen of the university of Victoria and andreas karch of the university of washington.

The tangled web that is gravityever since quantum mechanics was first proposed more than a century ago, the main challenge for physicists in the field has been to explain gravity in quantum-me-chanical terms. while quantum mechanics works extremely well in describing interac-tions at a microscopic level, it fails to explain gravity - a fundamental concept of relativity, a theory proposed by einstein to describe the macroscopic world. thus, there appears to be a major barrier to reconciling quan-tum mechanics and general relativity; for years, physicists have tried to come up with a theory of quantum gravity to marry the two fields.

“there are some hard questions of quan-tum gravity we still don’t understand, and we’ve been banging our heads against these problems for a long time,” Sonner says. “we need to find the right inroads to understanding these questions.”

a theory of quantum gravity would suggest that classical gravity is not a fundamental concept, as einstein first proposed, but

A diagram of a wormhole, a hypothetical “shortcut” through the universe, where its two ends are each in separate points in spacetime. (Credit: Wikimedia commons/Creative Commons Attribution-Share Alike 3.0 Unported license)


Society Telescopes for Hirethe Society has a wide range of telescopes for hire to members.

if you are looking to purchase or upgrade a telescope and are not sure what to buy, this is a very good way to evaluate some of the available equipment. See also the advertisement on the back page.

the Society does, of course, have more telescopes and other equipment, and you will start to see this equipment being made available to members as rental gear; including some equipment more suited for experienced members as well as beginners. three items that are now newly available for rental include:

• CelestronC55”SCToniOptronMinitowerComputerisedGoTomount

• CelestronNexstar55”SCTonacomputerisedGoToAlt/Azmountwithtripod

• Meade90mmAchromaticRefractoronamanualEquatorialMount.

if you have a project idea where this telescope or other Society equipment may help, particularly if you are happy to write a short article for the journal, please see Steve or Graham.

the Society is also keen to hear what members would like to have available for rental (the availability of the C5 scopes is in response to a member request for a more portable rental option). any submissions and ideas, or any questions or queries regarding rental equipment should go to rental Coordinator, Steve hennerley at [email protected] or on 027 245 6441

For advice on telescope maintenance, repairs or any other questions about astronomical Society instruments, Curator of instruments, Graham beazley can be contacted on 09 5371313/021 537610

rather emerges from a more basic, quan-tum-based phenomenon. in a macroscopic context, this would mean that the universe is shaped by something more fundamental than the forces of gravity.

this is where quantum entanglement could play a role. it might appear that the concept of entanglement - one of the most funda-mental in quantum mechanics - is in direct conflict with general relativity: two entan-gled particles, “communicating” across vast distances, would have to do so at speeds faster than that of light - a violation of the laws of physics, according to einstein. it may therefore come as a surprise that using the concept of entanglement in order to build up space-time may be a major step toward reconciling the laws of quantum mechanics and general relativity.

Tunnelling to the fifth dimensionin July, physicists Juan Maldacena of the institute for advanced Study and Leonard Susskind of Stanford university proposed a theoretical solution in the form of two en-tangled black holes. when the black holes were entangled, then pulled apart, the theorists found that what emerged was a wormhole - a tunnel through space-time that is thought to be held together by grav-ity. the idea seemed to suggest that, in the case of wormholes, gravity emerges from the more fundamental phenomenon of en-

tangled black holes.

Following up on work by Jensen and karch, Sonner has sought to tackle this idea at the level of quarks - subatomic building blocks of matter. to see what emerges from two entangled quarks, he first generated quarks using the Schwinger effect - a concept in quantum theory that enables one to create particles out of nothing. More precisely, the effect, also called “pair creation,” allows two particles to emerge from a vacuum, or soup of transient particles. under an elec-tric field, one can, as Sonner puts it, “catch a pair of particles” before they disappear back into the vacuum. once extracted, these particles are considered entangled.

Sonner mapped the entangled quarks onto a four-dimensional space, considered a rep-resentation of space-time. in contrast, grav-ity is thought to exist in the next dimension as, according to einstein’s laws, it acts to “bend” and shape space-time, thereby ex-isting in the fifth dimension.

to see what geometry may emerge in the fifth dimension from entangled quarks in the fourth, Sonner employed holographic duality, a concept in string theory. while a hologram is a two-dimensional object, it contains all the information necessary to represent a three-dimensional view. essen-tially, holographic duality is a way to derive a more complex dimension from the next

lowest dimension.

using holographic duality, Sonner derived the entangled quarks, and found that what emerged was a wormhole connecting the two, implying that the creation of quarks simultaneously creates a wormhole. More fundamentally, the results suggest that gravity may, in fact, emerge from entan-glement. what’s more, the geometry, or bending, of the universe as described by classical gravity, may be a consequence of entanglement, such as that between pairs of particles strung together by tunnelling wormholes.

“it’s the most basic representation yet that we have where entanglement gives rise to some sort of geometry,” Sonner says. “what happens if some of this entangle-ment is lost, and what happens to the ge-ometry? there are many roads that can be pursued, and in that sense, this work can turn out to be very helpful.”

February 2014 SOCIETY JOURNAL · 2014-02-03 · SOCIETY JOURNAL February 2014 February Monthly...

Documents

Transcript of February 2014 SOCIETY JOURNAL · 2014-02-03 · SOCIETY JOURNAL February 2014 February Monthly...