Untwinkling the Stars: Improving our view of the universe with laser guide star adaptive optics

The Earth's turbulent atmosphere blurs the images acquired with ground-based telescopes.  In principle, larger telescopes have smaller diffraction limits and can resolve the finer details of astronomical objects.  In practice, while a large telescope does reap the benefits of collecting more light, it can resolve details no better than a backyard 8-inch diameter telescope.  Placing telescopes at high altitude, such as on Mauna Kea in Hawaii, can reduce the atmospheric blurring, but does not eliminate it. One solution is to put telescopes in space, but there are limits to how large space telescopes can be and how many can be launched.  To take full advantage of large ground-based telescopes, one must use another approach.  Adaptive optics is a technology where the atmospheric turbulence is measured using either a natural star or a laser beacon and corrected in real time to "untwinkle" the stars and generate diffraction limited images.

Elinor will discuss how adaptive optics is implemented at Lick Observatory and the new technologies that they are testing for the next generation of adaptive optics instruments and giant telescopes.