Download presentation
Presentation is loading. Please wait.
Published byWillis Bond Modified over 9 years ago
2
7 th Annual GSC-II Project Meeting C B A S GSC-II and DSS-II Projects 2001 Annual Report Brian McLean 22 nd October 2001
3
7 th Annual GSC-II Project Meeting C B A S Project Goals Provide products/tools to increase efficiency of telescope operations and observation planning. ALL-SKY Will support HST, GEMINI, VLT, TNG and NGST Digitize available Schmidt Survey photographic plates Distribute 10x compressed images to community Build object catalogues from images Positions, Proper motions, Magnitudes, Colors, Classification Distribute to community Provide access tools to images and catalogue. Enable use for observing and science
4
7 th Annual GSC-II Project Meeting C B A S Community Partnership STScI recognized center for sky surveys. GSC-I DSS-I Created international consortium to develop and complete DSS-II and GSC-II projects. Collaborations Palomar/AAO ESO/ST-ECF,CADC SDSS science archive Tycho GAIA InstitutionDSS-IIGSC-II Space Telescope -European Coordinating Facility X European Space Agency - Astrophysics division X European Southern ObservatoryXX Osservatorio Astronomico di Torino X International GEMINI projectXX Canadian Astronomical Data CenterX Centre de Donnee StellaireX Anglo-Australian ObservatoryX Royal Observatory EdinburghX National Astronomical Observatory JapanX Beijing Astronomical ObservatoryX Palomar ObservatoryX
5
7 th Annual GSC-II Project Meeting C B A S DSS-II Overview Scan new survey plates from the Palomar and UK Schmidt telescopes All-sky, minimum 3 bandpasses (J, F, N) 15 ”) sampling, 23040x23040 pixels of 1.2 GB each STScI scan archive FITS images on MOD (8TB)+8mm tape backup 10x compressed images on-line in MAST CDROM jukeboxes being replaced by NAS RAID array 10x images distributed to ESO, CADC, CDS, NAOJ, BAO, ROE, GEMINI and Australian consortium. Photometric and astrometric calibration of all images calibrations provided in image headers SurveyNumber Plates (7952) POSS-I E880 POSS-I O880 Pal-QV614 POSS-II J897 POSS-II F897 POSS-II N897 SERC-J/EJ894 SERC-QV90 PPARC-ER288 AAO-SES606 AAO-GR109 UKSTU-IR894 Special XX6
6
7 th Annual GSC-II Project Meeting C B A S Summary of Plate Scans Notes to the First Generation Table. All scans (except POSS-I O plate) were made with 25 m (1.7”) sampling. [1] Used in the GSC-I. [2] These scans are part of the 102 volume CD set distributed as DSS-I. [3] Not published, but available on the STScI network server. [4] Plans include completing the -18, -24, and -30 degree zones as time permit. [5] Selected fields only. [6] About 150 J/EJ fields at the lowest latitudes are also being rescanned with 15 m sampling.
7
7 th Annual GSC-II Project Meeting C B A S GSC-II Overview All-sky catalogue of positions, proper motions, magnitudes and colours Use all available images : DSS-I/DSS-II images + unpublished (QV,XO) complete to a minimum of V=18 (Goal is plate limited) GSC-II will have ~5 billion entries for ~ billion objects GSC-II project is partially funded by external partners OATo, GEMINI, ESA/ST-ECF and ESA/SA Receive prepublication data access for telescope operations and science projects
8
7 th Annual GSC-II Project Meeting C B A S GSC-II Specifications Positions < 0.50 ” absolute; average across a single plate; < 0.20 ” relative, over 1/2 o field < 0.15 ” adherence to ICRS reference frame, average over all plates Proper Motions Errors due to limited time baseline between observation epochs typically 5-30 mas/year in North and 20-40 mas/year in South Photometry 0.2mag error between 12-18 magnitude Classification: 95% accuracy within two magnitudes of plate limit
9
7 th Annual GSC-II Project Meeting C B A S Improved Reference Catalogues Astrometric Reference catalogues TYCHO - 2 ICRS reference frame Now precision is limited by measurement error Photometric Reference catalogues Obtaining CCD sequences (14-18 magnitude) for all survey plates Second Guide Star Photometric Catalogue (GSPC-II) 95% sky observed Classification Training sets Availability of deep CCD catalogues over significant area Tools to allow visual classification of objects from plates
10
7 th Annual GSC-II Project Meeting C B A S Improved Plate Processing Improved software system to process images Sky determination and Object detection, improved deblending Position calibration using Tycho-2 (ICRS) Derived systematic corrections (Masks and Filters) Magnitude calibration using GSPC-II Improved vignetting function and derived emulsion sensitivity variations. Object classification using decision tree based on ranked object features All objects loaded into commercial object-oriented database (Objectivity) Database designed to support recalibration Use best available calibration during plate processing Recalibrate within database as algorithms/plate modeling/etc improved
11
7 th Annual GSC-II Project Meeting C B A S 2001 Highlights GSC 2.2.n deliveries Public release Internal science version DSS-II Plate scanning is approaching completion POSS-II completed UKSTU obtained observable missing fields UKSTU SES, ER and IV-N close to completion ‘B’ grade plates for ALL remaining southern fields Continued scanning IV-N plates and started POSS-I O Processing begun for IV-N plates Expansion of disk space for COMPASS 3.6TB on-line for ooDB files STScI will host SDSS public archive
12
7 th Annual GSC-II Project Meeting C B A S 2001 Lowlights Schedule slip GSC 2.2 delivered 3 months behind schedule Resource reductions Staffing – Garcia, Laidler, Morrison,Wolfe GSC 2.3 Schedule impact? Objectivity limitation DB pagefile issue will require DB rebuild 7 Missing POSS-II IV-N fields
13
7 th Annual GSC-II Project Meeting C B A S Catalog Release History GSC 2.0January 1999 Sky coverage prioritized for GEMINI SV, HST BOP Two-passbands (J,F), without proper motions Deliverable to GEMINI and ESO/VLT only GSC 2.1.0March 2000 Same as GSC 2.0, but with available sky coverage Preliminary application of astrometric masks GSC 2.1.1August 2000 Same as GSC 2.1.0, increased sky coverage Improved Photometric calibration with GSPC 2 Improved Astrometric calibration with Tycho 2
14
7 th Annual GSC-II Project Meeting C B A S Catalog Releases in 2001 GSC 2.2.0June 2001 99.9% complete sky coverage in 2 passbands to J=18.5 Computed error fields Initial community release (www, data-centers) GSC 2.2.01July 2001 Complete sky coverage in 2 passbands to J=18.5 Corrections to TYCHO entries GSC 2.2.1August 2001 Complete sky coverage to plate limit Internal consortium release for science and QA
15
7 th Annual GSC-II Project Meeting C B A S Planned Catalog Release GSC 2.3June 2002 ? Adds available XE, XO, QV plates + IR (XI, XN) Proper motions computed Reclassification with final decision trees Add links to Skymap, 2MASS, SDSS Improved precision, etc., depending on resources final astrometric masks and magnitude equation and vignetting Galaxy photometry Improved global error analysis and removal of systematic errors colour corrections proper motion corrections
16
7 th Annual GSC-II Project Meeting C B A S Goals for this meeting Celebrate GSC 2.2 Identify all critical issues related to GSC 2.3 Completion of calibration tasks GSPC 2.3 Magnitude equation Multi-plate tasks Galaxy photometry ReClassification QA Export catalog format GSC-II paper(s) SCIENCE PR plans
17
7 th Annual GSC-II Project Meeting C B A S Summary GSC 2.2 is already a success Satisfies requirements for telescope pointing Project approaching completion Solid infrastructure Scanning, Processing, COMPASS, GSPC-II BUT a lot of work remaining with limited resources GSPC-II, Recalibration/Reclassification,QA Need to keep focused on final goal Continue collaborative efforts STScI – production OATo – QA and Science ESO/GEMINI – Ops/Science feedback
Similar presentations
© 2024 SlidePlayer.com. Inc.
All rights reserved.