What advantages will JWST provide over a future 30-meter telescope on the ground?
JWST is designed to make observations that are not possible from the ground, regardless of ground-based telescope aperture. The Astronomy and Astrophysics Advisory Committee, which evaluates ground- and space-based programs by NASA, NSF, and the Department of Energy, commissioned an extensive report on the complementary natures of JWST and a 30-meter ground-based telescope (available at http://www.nsf.gov/mps/ast/aaac/reports/gsmt-jwst_synergy_combined.pdf). Between 1 and 2.5 microns, JWST’s strengths are complementary to those of the next-generation 30-meter aperture telescopes. Beyond about 2.5 microns, where ground-based sensitivity is severely limited by thermal emission from the atmosphere, JWST’s advantage in sensitivity will be immense, and JWST wavelength coverage extends to 28.5 microns. • What are the policies and plans for observing with JWST? The policies for JWST observers will be very similar to those of the other Great Observatories, with more than 80% of the observing t
