Balloon-borne Large Aperture Submillimeter Telescope

Balloon-borne Large Aperture Submillimeter Telescope
Name	Balloon-borne Large Aperture Submillimeter Telescope
Acronym	BLAST
Type	Stratospheric balloon telescope
Wavelength	Submillimeter (250–500 μm)
Operator	University of Pennsylvania; NASA; Columbia University; University of Toronto
First flight	2003
Location	Antarctica; Esrange; Kiruna

Balloon-borne Large Aperture Submillimeter Telescope The Balloon-borne Large Aperture Submillimeter Telescope operated as a stratospheric platform to observe far-infrared and submillimeter sky emission, enabling studies of star formation, galaxy evolution, and cosmology using a large-aperture cryogenic bolometer array. Developed through collaborations among research groups at institutions such as the University of Pennsylvania, Columbia University, and the University of Toronto, BLAST flew on long-duration balloon campaigns from sites including McMurdo Station and Esrange, delivering data complementary to satellites like Herschel Space Observatory and Planck (spacecraft). Its instrumentation and operations drew on heritage from projects such as BOOMERanG, MAXIMA, and SPIDER (balloon), while informing later observatories such as Atacama Large Millimeter Array and SOFIA.

Overview

BLAST was conceived to bridge gaps between ground-based facilities like James Clerk Maxwell Telescope and space missions like Spitzer Space Telescope, providing arcminute-scale mapping at wavelengths near the peak of dust emission. The project brought together teams from the University of Pennsylvania, Columbia University, University of Toronto, Cardiff University, Imperial College London, and agencies including NASA and the National Science Foundation. Using long-duration ballooning techniques pioneered by groups associated with NASA Wallops Flight Facility and launches from McMurdo Station and Esrange Space Center, BLAST targeted molecular clouds such as Orion Molecular Cloud Complex, Vela Molecular Ridge, and extragalactic fields observed by surveys like GOODS and COSMOS (survey). The program influenced instrument concepts used by collaborators at Harvard–Smithsonian Center for Astrophysics and Max Planck Institute for Radio Astronomy.

Design and Instrumentation

The BLAST payload featured a meter-class primary mirror, cold optics, and an array of transition-edge sensor bolometers cooled via helium refrigerators developed alongside groups at Jet Propulsion Laboratory and NIST. The optical design incorporated elements from submillimeter projects at Caltech and Cornell University, and detectors were fabricated with expertise from University of British Columbia and Cardiff University. Pointing and attitude control systems used sensors and actuators influenced by technologies from Lockheed Martin and tested with support from Columbia Scientific Balloon Facility. The payload integrated electronics and data systems similar to those on BOOMERanG and calibration strategies allied with Herschel Space Observatory instrument teams. Cryogenic systems benefited from collaborations with Pennsylvania State University and components tested at NASA Ames Research Center.

Science Goals and Observations

BLAST aimed to measure the spectral energy distributions of cold dust in star-forming regions and distant galaxies, constraining models developed by researchers at Caltech, Princeton University, and University of Cambridge. Observations targeted protostellar cores in regions cataloged by Infrared Astronomical Satellite and followed up sources identified by Submillimeter Common-User Bolometer Array on James Clerk Maxwell Telescope, and by SCUBA-2. Extragalactic surveys compared measurements to luminosity functions studied by teams at Yale University and University of California, Berkeley, and probed clustering statistics relevant to work from Harvard University and University of Chicago. BLAST data informed theories from groups associated with Sterzik Lab and models referenced in publications by researchers at Max Planck Institute for Astrophysics and University of Wisconsin–Madison.

Flight Campaigns and Operations

BLAST conducted multiple flights with varying durations, including a significant long-duration Antarctic flight launched from McMurdo Station and circumpolar missions supported by National Science Foundation logistics and United States Antarctic Program. Other campaigns operated from Esrange Space Center and launch facilities in collaboration with Swedish Space Corporation and personnel from NASA Johnson Space Center. Operations teams included staff from University of Pennsylvania, Columbia University, and University of Toronto, with mission planning informed by atmospheric studies from NOAA and stratospheric modeling groups at NCAR. Recovery and refurbishment activities involved partnerships with University of Oxford and engineering support from Ball Aerospace.

Data Processing and Calibration

Data reduction pipelines for BLAST adapted algorithms developed for BOOMERanG, Planck (spacecraft), and Herschel Space Observatory, with map-making and time-stream filtering implemented by teams at University of Pennsylvania and Cardiff University. Calibration used celestial standards such as Mars (planet), Jupiter (planet), and compact sources cataloged by Infrared Astronomical Satellite and IRAS teams, while cross-calibration efforts compared results to datasets from Spitzer Space Telescope and SCUBA. Systematic error characterization employed statistical techniques from groups at Princeton University and University of Chicago, and data archiving followed practices used by NASA/IPAC and European Space Agency archives.

Results and Impact

BLAST produced high-impact maps of Galactic star-forming regions, catalogs of cold cores, and measurements of the cosmic infrared background that influenced studies by Herschel Space Observatory and Planck (spacecraft). The project yielded publications with collaborators from University of Pennsylvania, Columbia University, University of Toronto, Imperial College London, and Cardiff University, and advanced detector and ballooning technology used by subsequent experiments like EBEX (experiment), SPIDER (balloon), and proposals to NASA Astrophysics Division. BLAST legacy products continue to support research at institutions such as Caltech, Harvard–Smithsonian Center for Astrophysics, and Max Planck Institute for Extraterrestrial Physics, and informed observing strategies for facilities including Atacama Pathfinder Experiment and South Pole Telescope.

Category:Balloon telescopes