NASA’s Roman Coronagraph tool has completed its testing phase at the Jet Propulsion Laboratory (JPL) in Southern California and has been sent to the Goddard Space Flight Center in Maryland. It’s set to aid the Nancy Grace Roman space telescope in its mission to explore habitable exoplanets outside our solar system. This instrument utilizes an advanced Coronagraph system, incorporating masks, prisms, detectors, and adaptive mirrors, all designed to reduce the brightness from distant stars, thus enabling the observation of planets orbiting them.
The primary goal of the Roman Coronagraph is to capture high-resolution images of exoplanets and dusty disks surrounding stars. Its aim is to achieve image quality that surpasses existing observatories by a significant margin, potentially reshaping the landscape of space-based imaging technology and paving the way for future advancements in telescopic systems.
“The Coronagraph instrument will suppress starlight so well that it should be two or three orders of magnitude more powerful than any other coronagraph ever flown onboard a space telescope,” NASA says.
“As light that has traveled tens of light-years from an exoplanet enters the telescope, thousands of actuators move like pistons, changing the shape of the mirrors in real time. The flexing of these “deformable mirrors” compensates for tiny flaws and changes in the telescope’s optics,” according to the agency.
At the heart of the Coronagraph’s capabilities lie its two flexible mirrors, each equipped with numerous actuators capable of real-time adjustments to compensate for optical imperfections. NASA emphasizes the remarkable precision of these mirrors, capable of correcting errors smaller than the width of a DNA strand.
During its evaluation at JPL, the Coronagraph underwent rigorous testing, including simulations of space conditions such as the “dark hole test.” By utilizing masks to block out the star’s light, the instrument enhances the visibility of faint objects nearby, a crucial technique for detecting exoplanets. Notably, the Coronagraph’s movable components allow it to actively mitigate unwanted starlight, distinguishing it as the first “active” coronagraph intended for space deployment.
NASA underscores the importance of directly imaging Earth-like exoplanets in the search for habitable worlds. While indirect methods have identified over 5,000 exoplanets, direct imaging has been limited, with fewer than 70 confirmed detections, most of which are larger and hotter than Earth. The advanced capabilities of the Roman Coronagraph offer new possibilities for imaging planets potentially capable of supporting life, especially those within the habitable zone of their host stars.
“At its maximum capability, it could image an exoplanet similar to Jupiter around a star like our Sun: a large, cool planet just outside the star’s habitable zone,” NASA says.
NASA envisions the Habitable Worlds Observatory, a proposed telescope concept aimed at imaging 25 Earth-like planets. The success of this ambitious project relies on technological advancements exemplified by instruments like the Roman Coronagraph. JPL’s Ilya Poberezhskiy, the project systems engineer for the Coronagraph, highlights the significance of active components, such as deformable mirrors, in achieving the goals of missions like the Habitable Worlds Observatory.
“The active components, like deformable mirrors, are essential if you want to achieve the goals of a mission like the Habitable Worlds Observatory,” said JPL’s Ilya Poberezhskiy, the project systems engineer for the Roman Coronagraph.