High contrast observations of bright stars with a starshade

• Published in: Experimental astronomy 2017-11, Vol.44 (2), p.209-237
• Main Authors: Harness, Anthony, Cash, Webster, Warwick, Steve
• Format: Article
• Language: English
• Subjects: Astronomical models; Astronomy; Celestial bodies; Chemistry and Earth Sciences; Computer Science; Extrasolar planets; Image contrast; Observations and Techniques; Original Article; Photometry; Physics; Physics and Astronomy; Stars; Statistics for Engineering; Technology
• ISSN: 0922-6435; 1572-9508
• DOI: 10.1007/s10686-017-9562-1

Starshades are a leading technology to enable the direct detection and spectroscopic characterization of Earth-like exoplanets. In an effort to advance starshade technology through system level demonstrations, the McMath-Pierce Solar Telescope was adapted to enable the suppression of astronomical sources with a starshade. The long baselines achievable with the heliostat provide measurements of starshade performance at a flight-like Fresnel number and resolution, aspects critical to the validation of optical models. The heliostat has provided the opportunity to perform the first astronomical observations with a starshade and has made science accessible in a unique parameter space, high contrast at moderate inner working angles. On-sky images are valuable for developing the experience and tools needed to extract science results from future starshade observations. We report on high contrast observations of nearby stars provided by a starshade. We achieve 5.6 × 10 − 7 contrast at 30 arcseconds inner working angle on the star Vega and provide new photometric constraints on background stars near Vega.