The balloon-borne large aperture sub-millimeter telescope Original Research Article

The balloon-borne large aperture sub-millimeter telescope (BLAST) is a new instrument to study galaxies at high redshift and to help answer questions about our galaxy and star formation. BLAST will fly from a long duration balloon. The telescope design incorporates a 2-m primary mirror with large-format bolometer arrays operating at 250, 350 and 500 μm with 149, 88 and 43 detectors, respectively. By providing the first sensitive large-area (≫10 deg2) sub-mm surveys at these wavelengths, BLAST will address some of the most important galactic and cosmological questions regarding the formation and evolution of stars, galaxies and clusters. Galactic and extragalactic BLAST surveys will do the following: (i) identify large numbers of high-redshift galaxies; (ii) measure photometric redshifts, rest-frame far-infrared luminosities and star formation rates thereby constraining the evolutionary history of the galaxies that produce the far-infrared and sub-mm background; (iii) measure cold pre-stellar sources associated with the earliest stages of star and planet formation; (iv) make high-resolution maps of diffuse galactic emission over a wide range of galactic latitudes. The BLAST long duration balloon experiment will also provide catalogues of 3000–5000 extragalactic sub-mm sources and a ≫100 deg2 sub-mm galactic plane survey which will serve as a legacy to be followed at other wavelengths and resolutions, including sub-arcsecond imaging with the Atacama Large Millimeter Array.