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From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

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Page 1: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

From Photons to Petabytes:Astronomy in the Era of Large Scale Surveys and Virtual Observatories

From Photons to Petabytes:Astronomy in the Era of Large Scale Surveys and Virtual Observatories

R. Chris Smith

AURA/NOAO/CTIO/LSST

Page 2: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

“Classical” OpticalAstronomy“Classical” OpticalAstronomy

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

Page 3: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

“Classical” Optical Astronomy“Classical” Optical Astronomy• 1-4 investigators propose for telescope time• Obtain 1 to 5 nights, or 1 to 5 hours!

Oversubscription on largest telescopes (e.g. Gemini) severely limits time per investigator

• Travel to distant telescope siteor not: Remote Observing, Service Observing, Queue

• Observeor not: clouds (OUCH!)

• Take .5 to 50 GB of data home (on tapes)• Reduce & Analyze “by hand”

Extract every detail from those bits Often takes months per night of data

Page 4: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

Optical WindowsOptical Windows

QuickTime™ and aMotion JPEG A decompressor

are needed to see this picture.

Page 5: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

Can “classical” techniques answer the BIG questions?Can “classical” techniques answer the BIG questions?

• Where do we come from?Star Formation, Nucleosynthesis

• Are we alone?Proto-planetary disks, search for planets

• Where are we going?Big Bang & the Expansion of the Universe

• What is the Universe made of?What types of matter? What types of energy?

Page 6: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

Where are we going? A “Repulsive” ResultWhere are we going? A “Repulsive” Result• In 1990s, began looking for deceleration

• Found expansion of Universe is accelerating!!!

• Implies something NEW!

• Regions of empty space REPEL each other?

“Cosmological constant”?

• Einstein’s greatest blunder… OR NOT?!!

Something going on in the vacuum?

• NEW FUNDAMENTAL PHYSICS!

Page 7: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

Today’s BIG Questions:Dark Energy & Dark MatterToday’s BIG Questions:Dark Energy & Dark Matter

Dark Energy is the dominant constituent of the Universe.Dark Matter is next.

95% of the Universe is in Dark Energy and Dark Matter, for which we have little or no detailed understanding.

1998 and 2003 Science breakthroughs of the year

Page 8: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

Attacking the Question of Dark EnergyAttacking the Question of Dark Energy• “Classical” approach won’t work

Not enough telescope time Difficult to control calibrations & systematics

• LARGE SURVEYS Goal: Provide large, uniform, well calibrated,

controlled, and documented datasets to allow for advanced statistical analyses

Control calibrations & systematics to <1% Larger collaborations provide both manpower and

diverse expertise• Including traditional astronomers, high-energy physicists,

mathematicians, and computer scientists

Page 9: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

Sociology of Dark EnergySociology of Dark Energy

• Dark Energy may be pushing the universe APART

• But it is pulling the Astronomy, High Energy Physics (HEP), and Computer Science (CS) communities TOGETHER HEP interests in fundamental physics HEP experience in large datasetsCS interest in CPUs, Storage, Networks, and (of

course) algorithms & optimization!

Page 10: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

Dark EnergyROADMAP to understandingDark EnergyROADMAP to understanding• Today

ESSENCE, large international group of astronomers

• Coming Soon to a telescope nearby Dark Energy Survey

• Camera built by Fermilab, majority DOE funding• Data Management System led by NCSA• Groups from Spain, United Kingdom, and Brazil recently joined

• The next BIG step LSST

• Camera built by SLAC, Data Mgmt with NCSA, • NSF + DOE funding, also inc. LLNL, Brookhaven, others

• Stepping UP Space-based work: JDEM (SNAP and/or others)

• NASA + DOE funding

Page 11: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

Today:ESSENCE (+SuperMACHO)Today:ESSENCE (+SuperMACHO)• Use a LARGE (~200 SNe), UNIFORM set of

supernova light curves to allow us to study the evolution of the expansion of the universe Constrain “w”, the equation of state parameter of Dark

Energy, to ~10%

• 30 half-nights per year for 5 years (2002-2006)• Use other half of nights to constrain possible

DARK MATTER candidates The ‘SuperMACHO’ project Search the Large Magellanic Cloud for microlensing

Page 12: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

Searching for Supernovae (and other transients)Searching for Supernovae (and other transients)

High-z SN Team

Page 13: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

ESSENCE+SuperMACHOThe data flows…ESSENCE+SuperMACHOThe data flows…• The telescope

CTIO’s Blanco 4m

• The camera MOSAIC 8Kx8K imager (67 megapixels)

• Exposures of 60s to 400s• Collect 20GB of RAW data per night• Data must be reduced and analyzed in near REAL

TIME (within ~10min)• Data ‘Reduction’ = >5x EXPANSION!

Roughly 3TB per year

Page 14: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

… and flows… and flows

• MUCH larger data flow than most other astronomical projects

• With ADDITIONAL complication of real-time reduction & alert requirement Must plan spectroscopic follow up on LARGEST

telescopes (Gemini, Keck, VLT, Magellan, …)

• We THOUGHT we were ready A few CPUs (cluster of 20 x 1GHz)A few disks (4 x 4TB “data bricks”)

• But…

Page 15: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST
Page 16: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

ChallengesChallenges

• Moving the data From Chile to the U.S.

• Storing the data Filling up racks with “data bricks” Keeping track of the data Initial database didn’t cut it

• Reprocessing the data Pipeline can keep up with real time flow But need to reprocess past years of data when

improvements are made to software

Page 17: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

Coming Soon (2009?):Dark Energy SurveyComing Soon (2009?):Dark Energy Survey• Investigate Dark Energy using 4 complementary

and independent methods Various types of distance measurements, based on

standard luminosities, standard yardsticks, and standard volumes

• Combine the results to provide the best (to date) constraints on the equation of state of Dark Energy

Page 18: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

The Instrument:Dark Energy CameraThe Instrument:Dark Energy Camera

Focal Plane:• 64 2k x 4k CCDs

• Plus guiding and WFS• 0.5 GIGApixel camera

Page 19: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

The Data:Dark Energy SurveyThe Data:Dark Energy Survey• Each image = 1GB• 350 GB of raw data / night• Data must be moved to supercomputer center

(NCSA) before next night begins (<24 hours) Need >36Mbps internationally

• Data must be processed within ~24 hours Need to inform next night’s observing

• Total raw data after 5 yrs ~0.2 PB• TOTAL Dataset 1 to 5 PB

Reprocessing planned using TeraGrid resources

Page 20: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

The Large Synoptic Survey Telescope – Massively Parallel Astronomy

The Large Synoptic Survey Telescope – Massively Parallel Astronomy

Survey the entire sky every 4-5 nights, to simultaneously detect and study: Dark Matter via Weak gravitational lensing Dark Energy via thousands of SNe per year Potentially hazardous near earth asteroids Tracers of the formation of the solar system Fireworks in the heavens – GRBs, quasars… Periodic and transient phenomena...…the unknown

Page 21: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

LSST: The InstrumentLSST: The Instrument• 8.2m telescope

Optimized for WIDE field of view (FOV)

• 3.5 degree FOV• 3.5 GIGApixel camera

• Deep images in 15-30s• Able to scan whole

sky every 4-5 nights

Page 22: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

LSST: Deep, Wide, FastLSST: Deep, Wide, Fast

Field of view (FOV)

KeckTelescope

0.2 degrees10 m

3.5 degrees

LSST

Page 23: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

LSST Site: Cerro Pachon in Northern ChileLSST Site: Cerro Pachon in Northern Chile

Soar

Gemini

LSST ~1.5m caltelescope

Support

LSST site plan

ElPenon

Gemini (South)SOAR

Page 24: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

LSST: Distributed Data ManagementLSST: Distributed Data Management

Long-Haul CommunicationsData transport & distribution

Base FacilityReal time processing

Mountain Sitedata acquisition, temp. storage

Archive/Data Access CentersData processing, long term storage, & public access

Page 25: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

LSST: The Data FlowLSST: The Data Flow• Each image roughly 6.5GB• Cadence: ~1 image every 15s• 15 to 18 TB per night

ALL must be transferred to U.S. “data center”• Mtn-base within image timescale (15s), ~10-20Gbps • Internationally within <24 hours, >2-10Gbps

• REAL TIME reduction, analysis, & alerts Send out alerts of transient sources within minutes Provide automatic data quality evaluation, alert to

problems Processed data grows to >100TB per night!

• Just catalogs >3 PB per year!

Page 26: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

DES, LSST, … and now for the REST of the ScienceDES, LSST, … and now for the REST of the Science• Ongoing (ESSENCE, SuperMACHO, etc.)

and future (DES, LSST, etc.) projects will provide PETABYTES of archived data

• Only a small fraction of the science potential will be realized by the planned investigations

• How do we maximize the investment in these datasets and provide for their future scientific use?

Page 27: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

The Virtual ObservatoryThe Virtual Observatory

• What is VO?Provides the framework for global access to the various

data archives by facilitating the standardization of archiving and data-mining protocols.

Enables data analysis by providing common standards and state-of-the-art analysis tools which work over high-speed wide area networks

• What is VO not?An organization funded to provide a single universal

archive of all astronomical dataA provider of resources (storage, computation,

bandwidth)

Page 28: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

VO: A Global EffortVO: A Global Effort

BR-VO

Page 29: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

VO ChallengesVO Challenges

• Provide Access to the Content Multiple distributed archives, some on the

scale of many petabytesArchives provide content, the VO knits those

resources together

• Provide the Standards Allow variety of archives talk to each other Develop generalized data model(s) for

different instruments/different wavelengths

Page 30: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

VO ChallengesVO Challenges

• Provide the User Interfaces Streamline data discovery, data understanding,

data movement, and data analysis

• Support the Analysis Support large queries across distributed DBs Support statistical analysis across results

(Grid)

• All the “boring” bits (infrastructure) Security, handshaking, resource management

Page 31: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

Chris Miller/NOAO

Page 32: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

VO Case Study: NOAO Data Products ProgramVO Case Study: NOAO Data Products Program• Management of data from all NOAO and some

affiliated facilitiesKPNO, including Mayall 4m (MOSAIC, NEWFIRM)CTIO, including Blanco 4m (MOSAIC, ISPI)SOAR & WIYN systems

• Virtual Observatory “back end”; CONTENTProvide access to large volume (TBs to PBs) of archived

ground-based optical & infrared data and data products

• Virtual Observatory “front end”; UI and TOOLSEnable science based upon distributed data and data

products, developing tools and services

Page 33: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST
Page 34: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

NVO portal @ NOAONVO portal @ NOAO

• Focus on Scientific USER

• First support data DISCOVERY

• NOAO Supported NVO Portals:http://nvo.noao.eduAnd for S.America…http://nvo.ctio.noao.edu

• 15Mbps for Chilean use!

Page 35: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

Many challenges ahead…Many challenges ahead…

• Security enforcing proprietary periods while allowing

PIs to combine data

• VOSpace virtual (and real) distributed workspaces to

collect and analyze data from many sites shared spaces for collaborations

• Combining GRID storage and CPU resources with VO queries and analysis

Page 36: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST

Strategic PartnershipsStrategic Partnerships

• In Local Systems Vendors: Local Storage, Processing, Servers

• In Remote Systems Supercomputer center(s) to provide bulk storage, large scale

processing (e.g., NCSA, SDSC’s SRB) Grid processing, storage

• Connectivity High-speed national and international bandwidth

• Scientific VO Partners to develop standards, provide tools Providing services to, and collecting feedback from, physics and

astronomy user communities Providing strong VO node in South America

Page 37: From Photons to Petabytes: Astronomy in the Era of Large Scale Surveys and Virtual Observatories R. Chris Smith AURA/NOAO/CTIO/LSST