The Balloon-borne Large-Aperture Submillimeter Telescope for polarization: BLAST-pol

• Main Authors: Marsden, G., Bock, J. J.
• Other Authors: Duncan, William D., Holland, Wayne S., Withington, Stafford, Zmuidzinas, Jonas
• Format: Book Part
• Language: English
• Published: Society of Photo-optical Instrumentation Engineers (SPIE) 2008
• Subjects: Arctic; Milky Way; Antarc*; Antarctica
• Online Access: https://authors.library.caltech.edu/90832/; https://authors.library.caltech.edu/90832/1/702002.pdf; https://resolver.caltech.edu/CaltechAUTHORS:20181112-085646846

The Balloon-borne Large Aperture Submillimeter Telescope (BLAST) is a sub-orbital experiment designed to study the process of star formation in local galaxies (including the Milky Way) and in galaxies at cosmological distances. Using a 2m Cassegrain telescope, BLAST images the sky onto a focal plane, which consists of 270 bolometric detectors split between three arrays, observing simultaneously in 30% wide bands, centered at 250, 350, and 500 μm. The diffraction-limited optical system provides a resolution of 30" at 250 μm. The pointing system enables raster-like scans with a positional accuracy of ~30", reconstructed to better than 5" rms in postflight analysis. BLAST had two successful flights, from the Arctic in 2005, and from Antarctica in 2006, which provided the first high-resolution and large-area (~0.8−200 deg^2) submillimeter surveys at these wavelengths. As a pathfinder for the SPIRE instrument on Herschel, BLAST shares with the ESA satellite similar focal plane technology and scientific motivation. A third flight in 2009 will see the instrument modified to be polarization-sensitive (BLAST-pol). With its unprecedented mapping speed and resolution, BLAST-pol will provide insights into Galactic star-forming nurseries, and give the necessary link between the larger, coarse resolution surveys and the narrow, resolved observations of star-forming structures from space and ground based instruments being commissioned in the next 5 years.