e-science telescopes for astronomical research iain steele liverpool john moores university
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e-Science Telescopes for Astronomical Research
Iain SteeleLiverpool John Moores University
http://www.estar.org.uk/
Lead Institutes
• Liverpool John Moores University– Astrophysics Research Institute
• Observational and Theoretical astronomers– Liverpool Telescope
• National facility (2 metre, fully robotic telescope)• Associated engineering team (optical, mechanical, electronic and
software)
• Exeter University– Department of Physics and Astronomy
• Observational and Theoretical astronomers• Small astronomical software group (mainly data reduction)
• Total funding (DTI, PPARC, EPSRC, JISC, STFC) ≈ £0.5M
Observational Astronomy
Science Challenge• Move from “Wavelength Exploration” to “Temporal Exploration” of
the Universe– Rapid reaction to “Targets of Opportunity”– Monitoring on timescales from seconds to years– Integrate archive and new data (“telescope as database”)
Hardware Requirements I
• Geographical Diversity
Hardware requirement II
• Different sizes and instrumentation
Hardware requirement III
• Flexibly Scheduled (ideally Robotic)
Sun Feb27 E2! Mon Feb28 B S/D ISIS Licandro Mon Feb28 I ! " Mon Feb28 E ! Mon Feb28 E2! Tue Mar 1 B N4 Groot ISIS Licandro Tue Mar 1 I ! ISIS Tue Mar 1 E ! Tue Mar 1 E2! Wed Mar 2 L C56 Zeilinger ISIS Evans Wed Mar 2 I ! " Wed Mar 2 E ! Wed Mar 2 E2! Thu Mar 3 L C56 Zeilinger ISIS Thu Mar 3 I ! " Thu Mar 3 E ! Thu Mar 3 E2! Fri Mar 4 L C51 Lopez-Sanchez ISIS Licandro Fri Mar 4 I ! " Fri Mar 4 E ! Fri Mar 4 E2! Sat Mar 5 L C52 Gorgas ISIS Lennon
PROPOSAL: PL00B18
THIS INFORMATION GENERATED AT Thu May 5 12:08:11 2005
* Priority: 0 * Allocated Time: 26.0 hours o BRIGHT EXCELLENT: 1.00 hours o BRIGHT AVERAGE: 12.00 hours o DARK EXCELLENT: 1.00 hours o DARK AVERAGE: 12.00 hours * Used Time: 16.21944 hours * Allocated Fixed Fraction: 0.0 * Used Fixed Time: 0 hours * Activation Date: 2004-07-29T15:00:00 WEST * Expiry Date: 2006-02-01T12:00:00 WET
Extra-Solar Sources:Name RA DEC PmRA PmDec Parallax RV2005am 9h 16m 12.47 -16 18' 16.00 0.0 0.0 0.0 0.02005M 9h 37m 32.36 23 12' 2.70 0.0 0.0 0.0 0.02005al 13h 50m 0.33 -30 34' 34.20 0.0 0.0 0.0 0.02004eo 20h 32m 54.19 9 55' 42.70 0.0 0.0 0.0 0.02004gs 8h 38m 23.18 17 37' 39.80 0.0 0.0 0.0 0.02004ef 22h 42m 10.2 19 59' 40.40 0.0 0.0 0.0 0.02004fz 2h 1m 6.41 31 52' 44.20 0.0 0.0 0.0 0.0
Software requirement:
• Common API for telescopes and databases• Distributed Allocation mechanism• Intelligent agents to act as my proxy• Security (authentication, integrity)
e-Science solutions
Agent Based Workflow
• User Agents - developed by astronomers to address their own science drivers. Can request and analyze data.
• Telescope Embedded Agents – telescopes or archives which deliver astronomical data or other resources.
• Protocols – Communication “carrier” - Web Services – Communication “syntax” - Robotic Telescope markup language (RTML).
User Agents
• Written in e.g. Perl, Python• Can be customized for particular science tasks• “Closing the observational astronomy loop”
What sort of variable?
• Mines SIMBAD to find variable stars at this location.
How much is known?
• Mines ADS, SIMBAD for papers, and for other data.
Scheduling Observations• Aim is a “global optimization”• Scoring model:
– Intelligent Agent requests a score from each Telescope Node.– Score reflects how well the object is positioned in the sky.– Can reflect weather, state of the telescope, how important what telescope is
doing already is etc.• Economic Model: (collaboration with IC, Southampton, Industry)
– “currency” which can be allocated by Time Allocation committees and used to negotiate a contract
– Airline model (book early for cheaper prices)– Auction Model (eBay analogue)
• Archives as well as telescopes can participate if they have the data already (ASTROGRID / Virtual Observatory)
• An international standard (“The HTN Standard” – Allan et al. 2006) has been agreed
Robotic Telescope Markup Language
• Defined by XML DTD– Extensible / backwards compatible– Implementation free definition
• Originally designed for real-time control (Hessman) (RTML v2.0)
• Extended to V2.1– Now observation (not control) based
• Freeware parsing tools (libXML (C), Perl) – some from our project, some from others
Delivering RTML
MANY DELIVERY STANDARDS OVER THE YEARS…
• Unix socket• Globus sockets• Grid Services• Web Services (cookie based authentication)• Web Services (certificate based
authentication)
Another part of the jigsaw … VOEvent
• Another XML Standard agreed internationally• Delivers notification of interesting events (not
specific observing requests)– WHAT– WHERE– WHEN– WHY– WHO
VOEvent Network
VOEvents in Google Sky
And it works…
First ever microlensing detection of an extrasolar planet in April 2005, incorporating data from Robonet…
And it works II …Date: Sun, 1 May 2005 22:16:30 -0400From: Bacodine <[email protected]>To: [email protected], [email protected]: GCN/INTEGRAL_POSITION
TITLE: GCN/INTEGRAL NOTICENOTICE_DATE: Mon 02 May 05 02:14:36 UTNOTICE_TYPE: INTEGRAL WakeupTRIGGER_NUM: 2484, Sub_Num: 0GRB_RA: 202.4403d {+13h 29m 46s} (J2000), 202.4982d {+13h 29m 60s} (current), 201.8971d {+13h 27m 35s} (1950)GRB_DEC: +42.6722d {+42d 40' 20"} (J2000), +42.6448d {+42d 38' 41"} (current), +42.9301d {+42d 55' 48"} (1950)
Date: Mon, 2 May 2005 03:18:40 +0100From: Engineer account <[email protected]>To: [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected]: GRB Alert : LT : OT CANDIDATE
I have completed detection mode.The best optical transient I could find has a position of 13:29:46.25 ,+42:40:27.50 (J2000).Thats at (approximate) pixel position (760.260010,567.530029) on the detectionmode images.It has a magnitude of 15.575000 (vs USNOB1) and counts 13166.900391.The astrometric fit has a residual of 0.160000 arc-seconds.The confidence level is 1.000000.I am confident that I have found an genuine OT.I am now changing to lt_ot_imaging mode.
15
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0 0.2 0.4 0.6 0.8 1Time (hours)
Mag
nit
ud
e
High impact scientific papers
• Steele et al, Nature 2009– First every optical polarization of a GRB
• Tanvir et al, Nature, 2009 – highest redshift GRB
• Gaudi et al, Science 2008 – first extrasolar solar-system analogue
• Beaulieu et al, Nature, 2006 – First extrasolar Neptune Mass Planet
• ~10 Astronomy Refereed Journal Publications
What has it delivered?
• Enhanced International Collaboration– YES. Standards used by many projects/facilities
• Data Sharing– Astronomers have always shared data anyway
• Better Sharing Methods– YES. VOEvent is a good example – sharing data about
interesting events in real time
• Software used by other projects– YES. Los Alamos RAPTOR, UKIRT, MONET all use our
software (and we use theirs)
More deliverables…
• Interaction with other disciplines– YES. First time I have worked with computer
scientists.
• Use of major NG or JISC investments– NO. Not appropriate to our domain (we are
telescope not computer limited!)
• Contributed back to larger research community?– LIMITED. Of interest to time domain astronomers
but not the general majority of astronomers.
Even more deliverables…
• Major Impact on your research programme?– YES. High profile scientific results that would have been
very difficult without• Major Impact on your education programme?
– NO. Small pilot. No real funding imperative.• Vision for e-Science in the future?
– Astronomy is deeply conservative in how it allocates and uses telescope time. Breaking the sociological barriers is the challenge, not technology. At present there is no “killer-app” that every astronomer wants/needs.
Final Thoughts
• Liverpool Telescope running cost ~ £1M/yr• The addition of ~0.1 M/yr e-Science funding has allowed
us to participate in (and in some cases lead) international projects with high scientific return
• Without the framework of having specific funding and objectives to create generic solutions we would have “hacked-together” something for some specific science problems, continually reinventing the wheel
• We are now well placed for participation in future high impact science projects (IceCube, LOFAR etc.) with little effort.