After the Big Bang, the dominant agent for evolution in the universe has
been the birth and death of stars. The continuing enrichment of the
interstellar medium of galaxies by the products of nucleosynthesis in stars
is responsible for the current elemental abundances of our galaxy and our
solar system. They, in turn, determine the nature of the physical processes
occurring in the universe today and set the stage for the emergence of
life. To understand the life cycle of stars, particularly the birth of
stars and the nature of star formation in the early universe, infrared
measurements are essential. The dense interstellar clouds where stars are
born are opaque to visible light. Infrared light readily penetrates the
clouds, allowing astronomers to directly observe the thermal emission from
newborn stars, circumstellar nebulae, and the clouds themselves. Because
light from the early universe is shifted toward longer wavelengths by the
relativistic expansion of space, the infrared also provides a window into
the time when stars and galaxies first formed.
Because thermal backgrounds from telescopes at
temperate sites swamp the astrophysical signal, it is difficult to study
the 3-5 micron band from the ground. For broadband studies, the thermal
background simply saturates the detectors.
Placing a large-format 3-5 micron camera at the South Pole overcomes this
problem. Because the site is so cold (typical wintertime temperatures are
-80 to -100 F), the background in the thermal IR is 20 - 50 times lower
than at temperate sites. This enormous advantage in sensitivity allows
small telescopes at the South Pole to outperform much larger telescopes at
CARA infrared instruments include:
Special page on IR results.
Site characterization information.