Google SkyGoogle SkyStatus and GoalsStatus and Goals

Data ResourcesData ResourcesSDSSSDSS DSSDSS PMMPMM COSMOSCOSMOS

CoverageCoverage 80008000 4000040000 4000040000 4000040000

SourceSource CCDCCD PhotoPhoto PhotoPhoto PhotoPhoto

BandsBands ugrizugrizJFN (N)JFN (N)

JFN (S)JFN (S)JFN (N)JFN (N)

JF (S)JF (S)JF (N)JF (N)

JFN (S)JFN (S)

DepthDepth 23.5 mag23.5 mag 21.0 mag21.0 mag 21.0 mag21.0 mag 21.0 mag21.0 mag

Plate scalePlate scale 0.45”0.45” 1”1” 0.5”0.5” 0.7”0.7”

RangeRange 32 bit32 bit 16 bit16 bit 8 bit8 bit 16 bit16 bit

StatusStatus JP2JP2 FITSFITS FITSFITS FITSFITS

SDSS DSS

COSMOS PMM

FusionFusion

Enterprise BoxEnterprise Box Delivered (fusion and server)Delivered (fusion and server)

200 sq degrees ingested and served200 sq degrees ingested and served SDSS reprocessed as compressed JPEG2000 (single SDSS reprocessed as compressed JPEG2000 (single

resolution)resolution) SDSS 280,000 regions, 8000 sq degrees 1300x1900 SDSS 280,000 regions, 8000 sq degrees 1300x1900

pixels (11m)pixels (11m) DSS 180,000 regions, 2500x2500 pixels (16m)DSS 180,000 regions, 2500x2500 pixels (16m)

Tested all skyTested all sky WMAPWMAP

Current StatusCurrent Status IssuesIssues

Timing for fusionTiming for fusion 350 frames (0.1% of SDSS)350 frames (0.1% of SDSS)

274986 tiles touched274986 tiles touched 2 days 17 hrs > 2000 days? 2 days 17 hrs > 2000 days? 2-3 hours to build pyramid of 14 levels2-3 hours to build pyramid of 14 levels

Merging assetsMerging assets Limit on number and resolution of assetsLimit on number and resolution of assets

All assets same resolution, must be broken into individual assetsAll assets same resolution, must be broken into individual assets Merged at project levelMerged at project level Auto mask -> feathering between assest (dark bands)Auto mask -> feathering between assest (dark bands) No mask -> does not build all resolution levels (appear at differnet zooms)No mask -> does not build all resolution levels (appear at differnet zooms)

ArtifactsArtifacts Detail at different zoomsDetail at different zooms Diffraction spikes etc – what will public acceptDiffraction spikes etc – what will public accept Image quality at polesImage quality at poles

Generic Reduction PipelineGeneric Reduction Pipeline

Simplify Astronomer’s IngestionSimplify Astronomer’s Ingestion Assumes World Coordinate SystemAssumes World Coordinate System

wcsOverlapwcsOverlap Calculates overlap between imagesCalculates overlap between images

wcsTanProjwcsTanProj Project onto tangent plane (base image and overlaps)Project onto tangent plane (base image and overlaps) Background subtractBackground subtract Lanczos interpolation (windowed sinc function)Lanczos interpolation (windowed sinc function)

imageColorimageColor Applies color mapping for input images (Lupton Applies color mapping for input images (Lupton

algorithm)algorithm)I ≡ (r + g + b)/3

R = r ∗ f(I)/IG = g ∗ f(I)/I B = b ∗ f(I)/I

Rotation and background

Color Definition

SDSS

DSS JFN

DSS JF extrapolate

Pipeline RequirementsPipeline Requirements Base Map Processing Estimates (no optimization)Base Map Processing Estimates (no optimization)

Fits reduction pipelineFits reduction pipeline 2-3 hrs per plate per color2-3 hrs per plate per color 10-20,000 hrs10-20,000 hrs

FusionFusion 24-50,000 hours24-50,000 hours

Space EstimatesSpace Estimates DSSDSS

7 TB (FITS)7 TB (FITS) 1.5 TB (1 arcsec, JP2)1.5 TB (1 arcsec, JP2)

SDSSSDSS 10 TB (FITS)10 TB (FITS) 1.2 TB (0.45 arcsec, JP2)1.2 TB (0.45 arcsec, JP2)

OptimizationOptimization Generate initial images on the fusion grid?Generate initial images on the fusion grid? Optimal input image size?Optimal input image size? Low priority queuesLow priority queues

ActionsActions Defining Coordinate SystemDefining Coordinate System

ICRS (J2000)ICRS (J2000) GIS: -180 to 180 deg GIS: -180 to 180 deg Astro 0 to 360 degAstro 0 to 360 deg New coordinate grid on sky, new client?New coordinate grid on sky, new client?

ProjectionProjection North up East left?North up East left?

Color BalancingColor Balancing Image scaling for bright stars Image scaling for bright stars

Images appear noisy at low zoomImages appear noisy at low zoom Recreate images at each zoom levelRecreate images at each zoom level

Balance between images/surveysBalance between images/surveys Need to optimize overlaps of DSS and SDSSNeed to optimize overlaps of DSS and SDSS Colors for astrophysics or public?Colors for astrophysics or public?

KML and CatalogsKML and Catalogs

Prototype of press release and catalog queryPrototype of press release and catalog query HST, SIAP, DBMSHST, SIAP, DBMS

ScalingScaling Querying images/pointsQuerying images/points

How many points, images in cacheHow many points, images in cache How many kml objects can be servedHow many kml objects can be served Need for addition astrophysics tagsNeed for addition astrophysics tags What altitudes to we view a set of pointsWhat altitudes to we view a set of points

Query based on field of viewQuery based on field of view

IssuesIssues

Data SourcesData Sources What catalogs/overlays for publicWhat catalogs/overlays for public

Hubble press releases, ACSHubble press releases, ACS Bayer, NGC/UGC, RC3, Clusters, Constellations Bayer, NGC/UGC, RC3, Clusters, Constellations

LayersLayers Layers of expertise for usersLayers of expertise for users

Deploying Google SkyDeploying Google Sky

How to get to BetaHow to get to Beta New Client or New databaseNew Client or New database

EC can do thisEC can do this How many base mapsHow many base maps Base map transparency?Base map transparency? What functionality in initial betaWhat functionality in initial beta

Coordinate system and gridCoordinate system and grid Excluding adsExcluding ads Licensing statusLicensing status What is the process to deploy to data centersWhat is the process to deploy to data centers

New FeaturesNew Features

Hierarchy of imagesHierarchy of images Small user – single image (OK)Small user – single image (OK) Large user – base map (OK)Large user – base map (OK)

More than one base mapMore than one base map Intermediate userIntermediate user

WMS standard interfaceWMS standard interface Fast but needs GS to cache imagesFast but needs GS to cache images Persistent and rapid update of imagesPersistent and rapid update of images How will things scaleHow will things scale

New FeaturesNew Features

Time/Frequency DomainTime/Frequency Domain Real time eventsReal time events

Press release (linked via CNN etc)Press release (linked via CNN etc) RSS feeds of new eventsRSS feeds of new events Sharing of events from users (comets, asteroids etc)Sharing of events from users (comets, asteroids etc)

Imaging surveysImaging surveys Multiple realizationsMultiple realizations

SDSS 25 repeats over 300 sq degreeSDSS 25 repeats over 300 sq degree LSST/PanSTARRS 100s over 20,000 sq degreesLSST/PanSTARRS 100s over 20,000 sq degrees Equivalent to different wavelengths (Xray, Near-IR)Equivalent to different wavelengths (Xray, Near-IR) Movie of the dynamic skyMovie of the dynamic sky

Embedding into Google Earth?Embedding into Google Earth? Provide sky around GEProvide sky around GE

Short-term Critical ActionsShort-term Critical Actions

Low priority processing queuesLow priority processing queues Need 40,000+ cpu hours Need 40,000+ cpu hours MapReduce (already reduced)MapReduce (already reduced) Which resources are availableWhich resources are available

Ingestion/MagratheanIngestion/Magrathean Enterprise box can store and serve final Enterprise box can store and serve final

products (network disk)products (network disk) Enterprise box cant process imagesEnterprise box cant process images