The Gemini Science Archive (GSA)

The Gemini Science Archive, the GSA, exists to provide a permanent archive for all science data from Gemini (N & S) facility (and some visiting) instruments. It additionally provides the mechanism whereby Gemini data is distributed to queue (including SV and DD programs) and classical program PIs via electronic transfer.

The GSA has been developed and is hosted by the Canadian Astronomical Data Center, the CADC, located at HIA in Victoria, B.C. Canada. The current Gemini and CADC Project Scientists for the GSA are Paul Hirst and David Bohlender, respectively. Severin Gaudet is the CADC GSA Project Manager.

Queries about the GSA should be sent via the Gemini HelpDesk.

Click on logo above or the following link to go directly to the GSA at CADC !

Alternatively, you can go to the URLs below. All these URLs take you to the CADC GSA web site.

http://archive.gemini.edu        http://gsa.gemini.edu        http://cadc.hia.nrc.ca/gemini

Note, you need a CADC user account before you can access the GSA for retrieval. If you do not already have an account then you can quickly obtain one via the registration form. Click on this link to go to the registration page CADC User Registration Page.

The Gemini Science Archive is powered by software developed by CONICYT and the CADC, and contains data and meta-data provided by the Gemini Telescopes.

April 1998: The Gemini Science Committee (GSC) endorsed the following resolution concerning a Science Archive for Gemini:

"The GSC thinks a Gemini science archive is scientifically compelling. Such an archive would provide the scientific community with tools for effective online access to all Gemini science data and supporting information in order to promote further scientific exploitation of those data. The Gemini Science Archive should guarantee that the valuable datasets obtained with the Gemini Telescopes are usable by future generations for research and education. The Project should further study the implementation and the resources required for a Gemini science archive."

The Gemini Board has endorsed the GSC views on a Gemini Science Archive, and agreed that the Project should study the specifications and requirements for a science archive.

September 1998: In order to provide a basis for the science archive conceptual design activities, Gemini sponsored a workshop to asses the feasibility of a viable Gemini Science Archive and recommend prioritized specifications and requirements for the science archive. The Science Archive Workshop was held on Monday 14 September 1998, in the Gemini Hilo Base Facility, Hilo, Hawaii. The recommendations of the Workshop are given below as is a summary of the presentations and discussions.

Workshop recommendations       Summary of workshop presentations and discussion

The Board also approved, for planning purposes, the use of a portion of Gemini operations funding for the development and continued support of a Gemini Science Archive. The Gemini Director has established a guideline of 5% of the Instrument and Facilities Development Fund (about $175K per year) for the continuing support of a possible Gemini Science Archive.

November 2000: The Functional and Performance Requirements Document and the Operational Concept Definition Document issued.  These documents can be viewed at the link below.

FPRD Document (PDF)

OCDD Document (PDF)

November 2001: A review of the GSA Phase II Operations and Development Plan is held at CADC, Victoria B.C. The final version of the resulting document, from August 2002, is presented at the following link.

GSA Phase II Development Document (PDF)

May 2002: Concept Design Document issued. This document can be viewed at the link below.

Concept Design Document (PDF)

January 2003: Documentation on the nature, extent and operation of the GSA and Meta-Data-Database, the MDDB, are generated. These documents are available via the links below.

Gemini Science Archive Overview Document (PDF)    MDDB Definitions Document  (PDF)

February 2003:  The GSA Phase II Development contract is signed by NRC, CADC and Gemini !!

March 2003: CADC staff visit Gemini North, Hilo for a week of finalizing basic archive capabilities, MDDB structure and content and operational model.

October 2003: The GSA Operations contract is signed. CADC will operate the GSA for an initial 5 year period.

November 2003: The prototype GSA, the GSAp, is released to the public on the first day of the November 2003 Gemini Board Meeting!

September 2004: Full Basic GSA 1.0 release to public! A milestone!

November 2004: Design Study proposal for Advanced Capabilities-1 "Electronic Transfer and PI Distribution" signed by Gemini/HNRC.

February 2005: Contract signed for AC-1 ETPIED mandatory components (Gemini/NRC).

March 2005: GSA Version 1.1 released. Included GNIRS, Michelle, Science Program queries, keyword queries, new dedicated web server, and SV data at CADC.

May 2005: GSA Version 1.2 released. Included Phase 1 of PI Electronic Distribution (raw data, weather data), MDF links, new database server for improved reliability and performance.

July 2005: Contract signed (Gemini/HNRC) for AC-1 ETPIED desireable components (advanced logging and reporting).

October 2005: GSA Version 1.3 released. Included Full PI Electronic Distribution (raw data, weather data, processed cals, iraf scripts/logs, xml science programs, readme files etc), Processed Cal query page, sacience results page linked to processed cals.

October 2005: Gemini DataFlow project DataManager transferring 'raw' data from Gemini South to GSA within minutes of acquisition. The 'raw' data is overwritten by checked/quality controlled data when available. Gemini North to follow suit in December 2005.

October 2005: GMOS-N and GMOS-S reduced pre-imaging data is ingested into GSA as soon as av available. PIs retrieve pre-imaging from GSA rather than sftp.

November 2005: First fully reduced Gemini data (GMOS imaging) published to VO world. Example datasets only, users can search for NGC891 and V1647 Ori on Datascope web site and see CADC/Gemini data!

November 2005: Discussions on VO-enabling GSA with aim of contract development for early 2006.

Early 2006: Additional GSA Advanced Capabilities requirements to be discussed and prioritized. Aiming for full VO presence in 2006. Features being discussesd are implementation of VO data model for GSA, World Coordinate System refinement at GSA, advanced source extraction and cataloging, advanced data (internal and external) associations.

The current GSA operational plan involved the following:

• Data acquired at Gemini North and Gemini South using facility instruments is sent directly to GSA via electronic transfer in 'raw' form.
• Ancillary meta-data is ingested into the MDDB at CADC.
• Gemini staff perform data quality control and assessment on 'raw' data and re-ingest checked data to GSA. This process can take a few days.

• Data and meta-data is available to PIs (with Phase 2 numeric keycode) as soon as it is ingested into GSA.

• Data and meta-data is available to the community after the proprietary period of 18 months has expired (3 months for SV data).
• Data headers are available to the community immediately upon ingest since these are considered non-proprietary.

OVERVIEW - Some brief help on GSA functionality can be found at the GSA web site under the 'Overview' link.

FORM HELP - Help on using the query forms including the format of queries etc can also be found at the GSA web site under the 'Form Help' link.

QUERY HELP - Under the GSA drop-down menus (blue bar) are several query links. The main drop-down menu users of the GSA will use is the "GSA Queries" item. Under this item are 7 entries. Briefly these do the following:

• Search for Science Data - Users can search the GSA for science data by coordinate or target name or other constraints. If the data is public (the proprietary period has expired) then the datasets can be marked and retrieved. If the data is still proprietary then the dataset is shown to exist but is not downloadable.

• Search Complete Catalog - The complete catalog of science and calibration data can be searched using any FITS header parameter as a constraint. Some canned queries are available but need to be expanded to all instruments.

• Search for Processed Calibrations - Search the GSA for reduced/processed calibration files. Search by Gemini program ID (e.g. GN-2005B-Q-1) or calibration type (e.g. bias). calibration table contains everything that has CALTYPE not equal to SCIENCE.

• Search Science Programs - Search xml science programs by Phase 1 keyword or title/abstract word, or PI/Co-I name etc.

• Find Weather Images - Find weather images for certain UT date/time or over period.

• Retrieve Gemini SV Data - Takes you to the GSA SV data package page. All SV data packages are ingested in GSA and in the future SV data itself will be available in the same manner as queue and classical data.

• Access your PI Data - Users with OT phase 2 numeric keycodes can authorize themselves to access their own proprietary datasets. Anyone (ANYONE!) with the Phase 2 numeric keycode can get access to that particular proprietary dataset so if Co-I's want data, the PI must give them to GEMPRGID and numeric keycode.

COOKBOOK - a GSA Cookbook is coming! Check back here often!

Based on observations obtained at the Gemini Observatory (acquired through the Gemini Science Archive), which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the Particle Physics and Astronomy Research Council (United Kingdom), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), CNPq (Brazil) and SECYT (Argentina).

Last update 10 October 2007; Rachel Mason