Multi-mission Archive at Space Telescope (MAST)
(Optical/UV Science Archive Research Center)
Supporting Organization:
Space Telescope Science Institute
3700 San Martin Drive
Baltimore, MD 21218
Overall Mission: MAST supports active and legacy mission data sets
and related catalogs and surveys, focusing primarily on data in the
ultraviolet, optical, and near-IR parts of the spectrum. Support includes
curation of the data, providing expert support to users of the data, providing
access to data-specific calibration and analysis software, providing user
support for this software, and maintaining public access interfaces to the
data. MAST works with new mission teams in the supported wavelength
regions to assist in the development of data management plans, especially in
the areas of data formats, descriptive metadata and standardization of
keywords, in the development of data access and data delivery plans, and
in assuring data quality control.
MAST Data Holdings
Name
Size
Number of Observations
Active Mission Duration
ACTIVE MISSIONS
FUSE
221 GB
2214
1999-
HST
8.6 TB
266,926
1990-
LEGACY MISSIONS
ORFEUS: BEFS
4.1 GB
332
Sept. 1993; Nov. 1996
ORFEUS: IMAPS
0.3 GB
643
Sept. 1993; Nov. 1996
ORFEUS: TUES
0.2 GB
229
Nov. 1996
EUVE
96 GB
1377
1992-Jan. 2001
ASTRO: UIT
56 GB
1,442
Dec. 1990; March 1995
ASTRO: HUT
0.6 GB
516
Dec. 1990; March 1995
ASTRO: WUPPE
0.1 GB
238
Dec. 1990; March 1995
IUE Final Archive
475 GB
103,552
1978-1996
IUE SIPS
125 GB
104,296
1978-1996
Copernicus
0.8 GB
551
1972-1981
CATALOGS & SURVEYS
SDSS: Early Data Release
1 TB
n/a
1998-
VLA-FIRST
109 GB
14,940
1993-
Digitized Sky Surveys
5 TB
n/a
1950-58, 1975-99
GSC I, II
2 TB
n/a
1950-58, 1975-99
Services Provided: MAST provides support for users seeking
to understand the properties and instrumental signatures of all archived
data sets and assistance with the interfaces to browse and retrieve these
data. Access to non-HST mission and instrument specific calibration
and analysis software and assistance in its use is on a best-effort basis
(full support for HST related software is provided by the MAST Helpdesk
and staff).
Non-HST Data Analysis Software Provided: IUE RDAF package
(IDL-based), IUE Final Archive processing software (IRAF port), EUVE analysis
software package (IRAF-based), Copernicus data analysis software (IDL-based),
UIT data reduction and analysis software (FORTRAN, C, and IDL routines),
WUPPE data analysis software (FORTRAN routines requiring the FITSIO library),
and HUT data reduction software (IRAF-based) are available through MAST.
Mission Interfaces:
MAST staff members continued to coordinate with the FUSE mission on data
ingest, creation of preview data, database queries, and web access. The FUSE
Project has undertaken a reprocessing effort to improve the quality of the
processed data and to provide files suitable for the "quick look" preview data
that are made available through the MAST archive.
Staff members coordinated with the GALEX team in drafting the Interface Control
Document (ICD), which specifies data characteristics, file structure, keyword
definitions, and delivery mode. A preliminary database has been created using
data models and file and keyword information. Test queries based on GALEX team input have
are being used to help define the user interface. A detailed testing and
implementation plan has been created, in preparation for the launch of GALEX
later this year.
MAST has developed working relationships with the teams from three planned NASA
missions: Kepler, a newly approved Discovery mission to detect planets; the
Cosmic Hot Interstellar Plasma Spectrometer (CHIPS), a University-class
Explorer mission; and the Spectroscopy and Photometry of the IGMs Diffuse
Radiation (SPIDR), a Small Explorer class mission. All three projects plan to
archive their data with MAST. Staff members continued to coordinate with teams
from the ORFEUS Project, the Sloan Digital Sky Survey (SDSS), and Voyager
UVS.
Interoperability Activities:
MAST is working with the Astrophysics Data
Centers Executive Council (ADEC) on a project to build a simple
interoperability framework among the NASA data centers. This project will
initially act as a referring service in a Web-based search, pointing MAST users
to relevant data at other data centers and alerting users at other data
centers of MAST data that may be of interest. This project has the
immediate goal of improving the interaction between data centers, and will also
help lay the interoperability groundwork for the VO.
MAST has provided leadership on a collaborative literature link project between
the ADEC and the scientific journals. The goal of the project is to define
ways to structure dataset identifiers and object names that can be used by
authors to identify datasets and astronomical sources in a published article.
This would permit the automatic association between journal articles and their
associated datasets and objects, and vice versa; the current MAST literature
link activity is labor-intensive. MAST staff members are developing a dataset
verifier tool to facilitate the literature link project as well as data
access among the various centers. The software tool parses a dataset name,
verifies the format, and checks for the existence of the dataset.
Major Activities and Accomplishments of the Past Year:
Data Ingest and Retrievals:
The rate of data ingested into the archive continued to grow, with 2.0 TB of
data coming from the active missions HST and FUSE. Data retrievals from the
same missions was 9.2 TB, which exceeds the size of the entire HST and FUSE
archives (8.8 TB). The addition of a RAID array to the distribution system has
permitted MAST to provide faster access to non-HST/FUSE data and a larger
staging area for HST and FUSE data. The non-HST/FUSE data originally stored on
a CD jukebox is now also stored on the RAID array, allowing immediate access to
the files.
The large size of ACS files poses logistical problems for transfer of these
files to users. Staff members created a
"FastAccess" area on
the MAST website from which users can retrieve popular and non-proprietary ACS
files via ftp, including ACS Early Release Observations (ERO) and the Great
Observatories Origins Deep Survey (GOODS) observations. Over 2500 individual
ACS files from the ERO and GOODS programs have been retrieved from the site by
about 200 users thus far.
MAST Data Ingest & Retrieval Activity
Date
Ingest Volume (GB) - Active Missions
Retrieval Volume (GB) - Active Missions
Retrieval Volume (GB) - Legacy Missions
Datasets Retrieved - Active Missions
Datasets Retrieved - Legacy Missions
Jul 2001
102.0
655.5
3.4
78572
2046
Aug 2001
129.9
717.2
2.0
92075
1260
Sep 2001
112.6
640.2
1.3
88996
2541
Oct 2001
126.4
690.3
7.9
93303
5869
Nov 2001
110.2
745.6
1.3
125264
4168
Dec 2001
105.2
682.1
6.8
101499
6038
Jan 2002
129.9
735.1
2.9
113238
7687
Feb 2002
109.2
690.0
7.0
85553
4310
Mar 2002
134.6
904.7
12.2
136705
5061
Apr 2002
257.0
957.2
5.2
89875
7146
May 2002
339.0
967.4
34.1
76942
26848
Jun 2002
382.8
832.8
2.0
69713
7493
TOTALS
2.0 TB
9.2 TB
86.1 GB
1,151,735
80,467
Research Tools for Data Exploration and Evaluation:
MAST members continued to develop new capabilties for researchers to locate
and evaluate data available from the archive.
Pointings Tables and Search Tool.
The new "pointings"
tool allows the user to search for HST images in a more
powerful way. A researcher may query the pointings tables to find
specific regions in the sky, i.e. pointings, that fulfill requirements
such as having been observed several times, in multiple bandpasses,
within a range of galactic latitude, and with a limited timespan. Tables
of pointings have been created for WFPC2, STIS, and FOC images thus
far.
MAST Scrapbook. The "MAST Spectral and Image
Scrapbook" allowed a researcher to select and view representative MAST data
for an astronomical object. The initial release, which included EUVE, FOS,
GHRS, HUT, IUE, and WFPC2, was enhanced with the addition of the STIS,
FOC, HUT, UIT, WUPPE, BEFS, and TUES data. In addition, staff members added
the capability to select and display selected scrapbook spectra from various
instruments. Editor's Note - Sept. 2024: The Scrapbook has since been retired.
High-Level Science Products: Guidelines have been established for
the contribution of
High-Level Science Products (HLSP) to MAST. HLSP are defined as fully
reduced and processed images and spectra from the MAST missions, as well
as closely related ground-based observations, theoretical data products,
object catalogs, and original reduction/analysis software. Science-ready
products currently available include atlases, sky surveys, and catalogs
created using various MAST mission datasets including HST, IUE, FUSE,
EUVE, Copernicus, and the Sloan DSS. In addition, major contributions are
expected from the HST Treasury, Archival Legacy, and Large programs begun
in Cycle 11.
WFPC2 Association Project:
A collaboration between MAST, the Canadian Astronomy Data Center (CADC),
and the ST-European Coordinating Facility (ST-ECF) was recently undertaken
to make combined WFPC2 images available jointly from each of the three
archives. These images represent combinations of individual WFPC2 images
of a given field taken with a given filter, and are being created for the
entire WFPC2 archive using software developed by CADC and ST-ECF. The combined images
will enhance the existing archives by providing deep images suitable for
scientific analysis and better previews of these fields.
User Interface Enhancements:
Customized and Multiple Spectral Plots. The interactive plotting
option, originally available on the HUT, IUE, and EUVE preview pages,
has been enhanced to handle WUPPE data. Users may also select spectra
from an IUE or EUVE search to coplot interactively. The coplotting
capability has been enhanced to allow scaling of individual spectra.
Ultraviolet Spectra from BEFS, HUT, and IUE for the Wolf-Rayet Star
HD 50896
Proposal Information. Observing program abstracts have been
placed online for IUE, and EUVE abstracts will soon be made available.
The abstracts are linked with
the associated data that were obtained under the individual programs.
The new information makes it possible for researchers to better understand
the observing strategy and techniques used by the original observers.
Links to the scientific publications complete the end-to-end documentation
of the scientific utilization of the data.
Scientific and Technical Publications:
Publications and Literature Links. The publications database
and the links between scientific publications
and the MAST datasets they involve were updated as new publications
became available through the ADS. About 1/8 of all publications involving
MAST datasets involved more than one mission. The HST publications database
was brought up to date following the same criteria used for other MAST
datasets. A list of MAST-based papers can now be searched at the Astrophysics Data
System (ADS), which now provides dedicated forms for HST and IUE papers,
accessible at
http://adsabs.harvard.edu/Groups/search/HST and
http://adsabs.harvard.edu/Groups/search/IUE. Users can search on all the usual
ADS fields, which include authors, object names, and abstract. Alternatively,
one can scroll down the ADS main page
(http://adsabs.harvard.edu/abstract_service.html), select "At least one of the
following groups (OR)", and then select HST and/or IUE from the group list.
Observatory Technical Publications. A pilot project was
undertaken to make handbooks and technical publications provided
by the various MAST missions easier for users to locate. Many of the
handbooks were not distributed widely or are now available only from the
MAST website,
but contain essential information for researchers working with the data.
A staff member worked with the ADS to create entries for the handbooks,
allowing researchers to query the widely used ADS database to locate the
technical information they need.
Press Releases. Three STScI press releases were based on MAST
data.
PR01-19: "Magnetic Fields Weave Rings Around Stars". Rings of material
were found around massive stars, formed due to stellar winds and magnetic
fields.
PR01-27: "New View of Primordial Helium Traces the Structure of
Early Universe". FUSE observations were used to find intergalactic helium,
tracing the structure of the early universe.
PR01-29: "Ancient Black Hole Speeds Through Sun's
Galactic Neighborhood". DSS images were used to discover a nearby ancient
black hole, XTE J1118+480.
Plans and Schedule for the Coming Year:
MAST plans to continue to enhance the interoperability and scientific
utility of our data holdings in the coming year through activities in the
following areas.
Additional Ultraviolet and Optical Data Sets
Continue to incorporate additional ultraviolet and optical data sets as they
become available, including data from the active missions FUSE and HST.
Complete preparations for supporting the GALEX data archive, including
the completion of the ICD, the database, and the user interface. GALEX
is expected to launch late this year, with the first delivery of data in
2004.
Coordinate with the Kepler project to put together plans for the
development of the ground system, including the Data Management Center
which will involve MAST. STScI will provide data receipt, calibration and
archiving of the photometry for 100,000 stars measured every 15 minutes
at extremely high precision over several years. Launch is planned for
2007.
Continue to work with new astrophysics mission projects, including
the CHIPS and SPIDR teams to assure access to these data sets via MAST
and to help them develop plans for data delivery and long-term data access.
CHIPS is expected to launch in late 2002, with the delivery of data
in 2004. SPIDR is expected to launch in 2005.
Improved Services for Archival Researchers
The Pointings tool will be enhanced by including additional datasets
and permitting queries of multiple tables.
MAST will continue to upgrade the MAST website to improve capabilities and
navigability. Complete the redesign of the catalog search software to make it
more flexible and maintainable. New capabilities will be incorporated to
improve search engines, handle very large databases, provide new interactive
research tools, and promote interoperability.
Staff members will work with Starview and Specview developers to
incorporate new spectral analysis tools into Starview and into the
web interface.
MAST will continue to provide assistance for archival researchers with
questions about searches, retrievals, data characteristics, analysis software,
and other issues related to MAST data.
Continue to acquire and make available High-Level Science data products,
including those from the HST Treasury, Archive Legacy, and Large programs
and the combined WFPC2 images.
Inter-archive Coordination Activities
In collaboration with the Chandra Data Archive (CDA), MAST will
implement an interface to coordinated HST/Chandra observing programs, which
will also link the two observatories in a more general way.
Continue leadership of literature link project through participation in
ADEC. Establish guidelines for electronic data identification
standards.
Participate in the development of prototype query services for the
National Virtual Observatory.
Continue active participation in the Astrophysics Data Center
Executive Council.