Improved mirrors and light masks have been demonstrated in the lab which would enable telescopes to directly image earth sized planets with a space telescope. This accomplishment marks a dramatic step forward for missions like the proposed Terrestrial Planet Finder, designed to hunt for an Earth twin that might harbor life. They have shown that a fairly simple coronagraph – an instrument used to “mask” a star’s glare – paired with an adjustable mirror, could enable a space telescope to image a distant planet 10 billion times fainter than its central star. For their next steps, Trauger and Traub plan to improve the suppression of speckles by a factor of 10, and extend the method to accommodate many wavelengths of light simultaneously.
Three simulated planets — one as bright as Jupiter, one half as bright as Jupiter and one as faint as Earth — stand out plainly in this image created from a sequence of 480 images captured by the High Contrast Imaging Testbed at JPL. A roll-subtraction technique, borrowed from space astronomy, was used to distinguish planets from background light. The asterisk marks the location of the system’s simulated star. Image credit: NASA/JPL-Caltech