Deformable Mirrors in space may help find alien life in universe

Deformable mirrors (DM) are mirrors whose surfaces can be bent to achieve wavefront control and optical aberration correction, and their shape can be controlled with speed. 

National Aeronautics and Space Administration (NASA) said that these mirrors may enable direct imaging of exoplanets by correcting imperfections or shape changes in a space telescope down to subatomic scales. Notably, deformable mirrors are used in conjunction with wavefront sensors and real-time control systems in adaptive optics. 

Scientists always look for Earth-like planets orbiting neighbouring stars and study them so that we can find whether or not we are alone in the universe. While doing so, it is vital to directly photograph such planets to investigate them and determine whether they can support life. 

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The reality is that these planets are difficult to see because the host star's light obscures them with its brightness. Hence, a coronagraph apparatus can be used to reduce the host star's glare light, which will allow the reflected light from the planet to be captured. 

A report by NASA stated that a deformable mirror is a crucial component of a coronagraph because it can repair even the smallest flaws in the telescope. It can also remove any remaining starlight contamination. 

NASA report said in a report published on November 21, "Detecting an Earth-like planet poses significant challenges as the planet is approximately 10 billion times fainter than its parent star. The main challenge is to block nearly all of the star's light so that the faint light reflected from the planet can be collected." 

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The report said that a coronagraph can filter starlight, but any instability in the telescope's optics can result in starlight leakage, generating glare that obscures the planet. 

Hence, the NASA report said detecting an Earth-like planet using a coronagraph requires "precise control of both the telescope and the instrument's optical quality, or wavefront, to an extraordinary level of 10s of picometers (pm), which is approximately on the order of the size of a hydrogen atom". 

NASA said in the report that future space coronagraphs will be able to reach this level of control because of flexible mirrors. These devices will be tested in space on a coronagraph technology demonstration instrument aboard NASA's Roman Space Telescope, which is scheduled to launch in May 2027.