A Flexible Mirror Is A Step Towards The Search For Life Outside Of Our Solar System

Even in the vast expanse of space, the smallest detail can make a big difference. A launch experiment soon from MIT shows how. The demonstration mission of deformable mirror (DeMi) CubeSat will test a new mirror of the telescope before the end of the year. It could equip future satellites with the tools to find the exoplanets most likely to contain life.

What makes this mirror exceptional cannot be seen until you get close. Behind its reflective surface, there are 140 small actuators that will allow the mirror to bend and adapt to obtain clearer light readings from stars outside our solar system.

These changes are necessary because when you are in orbit, conditions can be difficult. One side of your satellite may be burning in the sun, while the other side may be very cold. As the temperature changes, the pieces change size and move. Spinning and pushing can also make things vibrate. "All these disturbances make small spots on the photos you're taking," says Kerri Cahoy, an associate professor of aeronautics and astronautics at MIT.

To solve this, the mirror can detect errors in the image and bend to correct them. He does it by analyzing the light when he hits the mirror. Printed circuit boards send signals to the bars, which adjust the shape of the mirror accordingly. It does not need to move much: we are talking about 10 to 20 nanometers. But these slight changes could combat any distortion in the light that the telescope is catching. "One good thing about this type of technique is that the contrast is very good," says Paula do Vale Pereira, a Ph.D. student at MIT and mechanical leader of the project.

Researchers could use a larger version of this deformable mirror to take better images of the stars, block the light of a star and obtain images of nearby exoplanets. The mirror will also help them to capture the light more clearly so that they can see the spectrum of gases that the planet is emitting. This provides information on the composition of its atmosphere, says Cahoy. That could give us a clearer picture of the things we are observing outside of our solar system.

While this is only a test to ensure that the mirror works in space, future missions that use larger versions will look for gases such as carbon and traces of water to give clues to life.

The technique may be new in space, but it has been used on Earth for years to combat the distortion caused by our own atmosphere. Terrestrial observatories have mirrors that adapt many times per second in response to readings of how winds and atmospheric gases affect light.

Eventually, the data from this small experiment will inform future space telescopes. Researchers would love for the next "to have the ability to find out if there is life on another planet by observing the spectra of a planet or other star," says Cahoy.

By: Preeti Narula

Content: https://www.technologyreview.com/s/613597/a-bendable-mirror-is-a-step-toward-finding-life-outside-our-solar-system/