Multi-mission Archive at Space Telescope (MAST)
(Optical/UV Science Archive Research Center)
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 delivery plans, and
assuring data quality control.
MAST Data Holdings
Number of Observations
Active Mission Duration
Sept. 1993; Nov. 1996
Sept. 1993; Nov. 1996
Dec. 1990; March 1995
Dec. 1990; March 1995
Dec. 1990; March 1995
IUE Final Archive
CATALOGS & SURVEYS
SDSS: Early Data Release
Digitized Sky Surveys
GSC I, II
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 continues is on a time-available basis. Full
support for HST related software is provided by the MAST Help Desk and
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/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.
In September, 2002 FUSE Project began reprocessing all
and new data with a new pipeline system. The reprocessed version
contain new data products, such as files which can alert the PI
to image wander during an exposure. The products also contain
several types of browse products, both coadded for each "channel"
(wavelength range) of an observation and also for constituent
exposures that constitute a FUSE "observation." Use can browse
these images to search the pre-extracted spectral images for flaws,
for image draft, and for trends in count rate.
As the reprocessed data are ingested,
they supplant the older data version. The MAST contract with FUSE
ended on March 31, 2003, limiting MAST's role to continuation of
On April 29, 2003 the GALEX
satellite was launched. (This satellite will survey images and spectra
in the UV, including an all-sky image survey, to faint light limits.)
To prepare for the data archiving,
MAST and CalTech co-wrote an Interface Control Document with the GALEX
In anticipation of a small small data release in late 2003, MAST
staff have created a database management system based on Microsoft
SqlServer. Using simulated data products from the GALEX Project, MAST
wrote and tested ingest procedures on its GALEX webserver. This website
is now open to the public but at the moment serves simulated data.
Ultraviolet spectropolarimetric previews have been received from
the WUPPE Project
and ingested into the MAST database.
MAST is working with the Astrophysics Data Center
(ADEC) on a project to build a
simple interoperability framework among the NASA astronomical data
centers referring service in a web-based search in a Web-based
search, pointing MAST users to relevant data at other data centers
and alerting users at these other centers of MAST data that may be
of interest. This project has the immediate goal of improving the
interaction between data centers and of laying the framework for
the National Virtual Observatory.
ACTIVITIES AND MAJOR ACCOMPLISHMENTS OF THE LAST YEAR
Data Ingests and Retrievals:
The combined active mission (HST, FUSE) annual data ingest rate
increased markedly to 5.8 TB, raising the total to 14.0 TB. This
upturn was due mainly to the addition of data from the ACS and
NICMOS instruments, which started operations late in the previous
year. For all major missions (active and archival) the number of
requested datasets has increased over the past year.
Over the last year a new data storage array was delivered to the
Institute. Staff have completed the the migration of DADS data
(HST, FUSE), as well as data previously stored in other media.
MAST Data Ingest & Retrieval Activity
Ingest Volume (GB) - Active Missions
Retrieval Volume (GB) - Active Missions
Retrieval Volume (GB) - Legacy Missions
Datasets Retrieved - Active Missions
Datasets Retrieved - Legacy Missions
*As MAST does not maintain retrieval statistics for DSS and SDSS, the number of searches are displayed to show the interest level in these datasets.
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
and the Great Observatories Origins Deep Survey (GOODS) observations. This service
also reduces the number of requests made to the sometimes overloaded DADS retrieval system.
All the GOODS observations were completed May 27, 2003.
The FastAccess service was a great success with over 900 unique computer domains (users) retrieving over
1.2 TB of data (25,000+ files) over the past year.
Near the end of the year, the ACS/ERO and some of the GOODS data
were temporarily removed from the FastAccess area due to lack of space on the new
RAIDTEC staging array. The data are now available from the new EMC storage area.
New Storage Media:
A 32 Terrabyte RAID array purchased from the EMC Corporation will
serve as the new primary storage/backup medium for all DADS, MAST, and
GALEX datasets (as well as a staging area for OTF and OPUS operations).
A RAIDTEC array purchased the previous year is now being used for
FastAccess data (see below) and as a staging area for DADS retrievals.
Improved MAST Services:
document "How MAST Works" has been posted for users of MAST data to
and data flow within the organization.
A survey of MAST users was conducted to provide feedback on the
efficiency and usefulness of various MAST services. A major concern
expressed in the responses was the lack of a secure FTP site for
uploading of proprietary data. A request for a compilation of most
popular HST proposals was approved and implemented. The resulting
list of programs shows that "SNAP" proposals" are those most
frequently utilized, thus providing feedback to the TAC on reviews
of new HST proposals.
Data Discovery/Search Tools:
Scrapbook and Pointings Table:
STIS and NICMOS images were added to the Spectral/Imaging Scrapbook.
New datasets are added to the Scrapbook table each month from HST
and FUSE observations. Data for active instrument missions, such as
for STIS, WFPC2, and NICMOS, are added weekly the Pointings Table.
This chart shows the number of times each tool was used for a search or display over the past year.
The first set of HLSP from the
(Great Observatories Origins Deep Survey) HST Treasury program
have been delivered to MAST.
In addition to these HLSP data being visible through the HST and HLSP
they may be accessed via anonymous ftp
A HLSP search
form has been created similar to those for actual MAST missions.
This form allows searches based on project name, object coordinates,
target name. It also permits searches based on instrument, product
type (image, spectrum, or catalog), and file format. The results
pages for all missions now include a column pointing to any HLSP
dataset. The plots below show time histories of data volume (GB)
of HLSP data downloaded each month and the number of new users
(computer domains) added. The roughly constant positive slope in
the latter plot shows that many new astronomers are still discovering
this data resource.
WFPC2 Associations: The Canadian Astronomical Data Center
the Space Telescope
- European Coordinating Facility
ST-ECF , and MAST collaborated in
creating and providing access to a set of ~16,000 combined
image datasets from the current archive of ~50,000
individual WFPC2 observations recorded in the MAST/HST archives.
These associations are coadded datasets for sky regions observed several
times and facilitate usage with the highest quality WFPC2 images.
The grayscale figure shows an example of a WFPC2 association image
(right) and one of its constituent observations (left).
Atlases: spectral atlases (FUSE data of OB stars, and IUE data of
pre-main sequence stars). One of these atlases includes computed
spectra of H2 absorptions for an array of column densities,
while another includes identification of metallic interstellar features.
These presentations are of special
value to all FUSE proposer interested in distant objects near the
Galactic plane. An image atlas of the Helix nebula has also
been added to the HLSP collection. Newly observed data continue to be
added to the existing Magellanic Cloud Planetary Nebula HLSP site.
User Interface Enhancements:
Proposal abstracts searches:
Abstracts for the IUE mission have been optically scanned and
entered into a database, permitting searches of them by author
A similar text-search program has been implemented for HST, FUSE,
and EUVE proposals, thus enhancing the search capability for
programs in these missions.
A new search interface form has been written in the PHP scripting
language for the MAST missions. This interface includes expanded
functionality and more standardization in queried parameters among
different MAST missions. Search results can be listed in multiple
formats, including the newly adopted VOTable format of the NVO.
A dataset verifying tool has been written that allows a user to
determine the essential attributes of an input name of a MAST
dataset. This tool will be used for verification of dataset names
by authors submitting lists of these names to the Astrophysical
Data System (ADS) catalog.
The Astrophysical Data Centers Executive Council:
MAST has played an active role within the ADEC
to coordinate and provide common standards for the data services
of NASA's astronomical data archive centers. Acting on request
from NASA/OSS's Science Archive Working Group, the ADEC wrote and
submitted a white paper on "NASA Science-Archive Interoperabililty"
Acting on Headquarters request, the ADEC wrote and submitted a
white paper on "NASA Science-Archive Interoperabililty" to NASA
Headquarters (no formal response, as of this writing).
The publications database and the links between scientific
papers and the MAST datasets they link to were regularly updated
as new citations became available through the ADS. About 1/8 of
all papers utilizing MAST datasets referred to more than one
Press Releases from MAST Data (HST-archival only):
PR02-15 "Colorful Fireworks Finale Caps a Star's Life" - R. Fesen
PR02-23 "Odd Couple Widely Separated by Time and Space" - R. Knacke
PR03-05 "Scientists Find Faint Objects with Hubble that May
Have Ended the Universe's 'Dark Ages'" - H. Yan
PR03-06 "Close up of M27, the Dubbell Nebula" - C. O'Dell
PR03-07 "Hubble Resolves a Blaze of Stars in a Galaxy's Core"
- M. Tosi
PR03-09 "Rainbow Image of a Dusty Star" - R. Sahai
PR03-13 "Hubble Captures a Perfect Storm of Turbulent Gases,"
- J. Nester
JHU Press release: "Uncovering a Hidden Supernova Remnant" - C.
JHU Press release: "Cooling off the hottest stars," L. Bianchi and
PLANS FOR COMING YEAR
MAST will ingest of GALEX Data release "0" in the fall of 2003.
This will mark the inauguration
of the MAST public website (see figure) many new features such as
"active images" and the ability to plot returned data on line.
MAST will respond to the Kepler mission's request for a level
of support of technical developers in fall, 2003 and coordinate
with the Kepler Program manager and OPUS (both are STScI entities).
Kepler will be launched in 2007, will observe obtain brightnesses
of 100,000 Sun-like stars every 15 minutes, and ultimately archive
its data products (some 0.5 TB) within MAST,
MAST will ingest of UVSTAR (Shuttle mission) spectral data products,
MAST will design help and data-retrieval web pages for the CHIPS
mission. Ingest of CHIPS data is expected in the late-2004.
New services for archival research:
Interfaces will be constructed
to allow HST/FUSE PIs to authorize other users and oneself to
access proprietary data rather than having to set up an account,
Interface scripts formerly written in CGI will be rewritten
in PHP to permit more complicated queries and to make them adaptable
as templates for interfaces to other missions,
The Spectrum Coplotting tool will provide the capability of
displaying a mean-averaged spectrum for a set of input of spectra
from the same instrument and grating/dispersion configuration,
An enhanced website for GALEX researchers will be designed for
on-line queries, browsing and data-plotting (see plot),
The reprocessed FUSE dataset will be added to the Spectral Scrapbook,
WFPC2 associations and ACS data will be included in the Pointings
Using the HTM sky-meshing scheme, MAST will construct a field-of-view
"footprint" service, first for GALEX and then other missions.
This service will
return a list of all observations from MAST missions that encompass
a pair of coordinates specified by a user of tne service,
Adding search interface for press releases for STScI's Office of
Thumbnail of GALEX data "return page" from querying on an observed object
(data are simulated). Click on thumbnail for larger version
or go to the
MAST will continue to vigorously support activities of the
Astrophysical Data Centers Executive Council, and the International
Virtual Observatory Alliance (NVO).
MAST will assist in the development of spectral format protocols
analogous to the Simple Image Access Protocol as well as new
applications written with this protocol.
MAST will coordinate with other archiving centers to implement common
interfaces for coordinated observing programs, such as the HST/Chandra
With SIRTF and IRSA, MAST will participate in setting up standards for
the access of data from multiple arctive centers to center-wide tools, such
as an interarchive-center Scrapbook,
The Pointings table will be enhanced to permit cross-instrument searches.
Continued Services to Archival Researchers:
CADC and MAST will create and stage a second group of WFPC2
association images and associated catalogs of all objects in them
will be generated. Similar work will begin on ACS associations,
previews, and catalogs,
MAST continues to acquire and make available High-Level Data
Science Products, such as spectral and image atlases,
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.
Drafting of next senior review proposal to NASA.
This document will detail MAST activities over the last four years
and describe plans for the future.