NASA’s upcoming Nancy Grace Roman Space Telescope, set to launch as early as next month, aims to revolutionize our understanding of the cosmos through its innovative technology. One of the key features of this mission is the first space-bound active coronagraph, an advanced instrument designed to minimize the overwhelming light from stars during observations. This capability will enable astronomers to capture images of exoplanets that resemble those in our solar system, potentially paving the way for future missions aimed at photographing Earth-like worlds. Brandon Creager, the lead mechanical engineer for the instrument at NASA’s Jet Propulsion Laboratory (JPL), emphasizes the telescope’s significance, stating that it could serve as a crucial stepping stone in the quest to find planets like Earth.
The Roman telescope is equipped with a wide-field camera boasting approximately 300 megapixels, allowing it to capture images that are about 100 times larger than those of the Hubble Space Telescope at similar resolutions. This enhancement will enable scientists to delve into the mysteries of dark matter and dark energy, as well as discover a multitude of new exoplanets. Harvard research scientist Javier Via likens the telescope’s capabilities to shifting from interviewing a few individuals to conducting a comprehensive global census, underscoring the leap in observational power. The coronagraph will focus on one stellar system at a time, providing an unprecedented view of the space surrounding stars and enabling the detection of smaller, dimmer exoplanets that were previously hidden from view.
Unlike earlier coronagraphs used in space telescopes, the Roman’s design incorporates two deformable mirrors that employ active wavefront control to counteract unwanted light. This cutting-edge technique allows the telescope to measure and suppress stray light before observations, creating a clearer view of potential exoplanets. Each mirror is fitted with a grid of actuators, which can make minor adjustments to shape the mirror’s surface precisely. This meticulous control results in a doughnut-shaped region around the star where starlight is suppressed, enhancing the visibility of exoplanets. As a result, the Roman telescope is expected to significantly improve the sensitivity to exoplanets against the glare of their host stars, potentially revealing planets that were previously undetectable. The intricate combination of mirrors and masks will guide preserved planetary light towards the detectors, marking a new era in the direct imaging of exoplanets and opening the door to discovering true Jupiter analogs orbiting sun-like stars.
Source: Shape-shifting mirrors on NASA’s new space telescope could unveil Jupiters like our own via MIT Technology Review