Not so long ago in resignation was sent to the space telescope “Kepler”, which scientists have confirmed the existence of thousands of exoplanets. His successor, TESS goes to work instead of “Kepler” and is going to find more celestial bodies. But after we find exoplanets, for more information about them we need large and more powerful space telescopes. These telescopes need a very large mirror — much like the space telescope James Webb, the launch of which is constantly delayed.
It will use a 6.5-meter mirror for the observation of extremely distant galaxies. And like James Webb, mirrors for space telescopes of the future could consist of many individual segments — Webb 18.
How to see an exoplanet?
Although such design does allow to send into space very large telescopes, it has its problems. For example, the need for exceptional stability. “Any disturbance on the spacecraft, a small change of the slope, turn off electronics item, change the amount of heat dissolving in the cosmic system — this will lead to easy expansion or compression of the structures,” says MIT postdoc Evan Douglas. “If the disturbance exceeds 10 PM, you will begin to see changes in the structure of the stellar light inside the telescope, and these changes will mean that you will never be able to completely obliterate the star light to see the reflected light of the planet.”
It all boils down to is that if the telescope is extremely stable, its measurement will be incorrect and will affect observations of distant exoplanets.
Scientists can use laser light directed from the earth to the sky, as a way of pointing and stabilization of telescopes. This idea was pappasallis researchers from the Massachusetts Institute of technology, assuming that in the future, we will use small satellites, such as CubeSats, to manage large space telescopes using laser light. “Instead of having to guide the laser from earth to space, we radiate it from space to the telescope in space,” says Douglas.
Their idea, the scientists described the study, published in the Astronomical Journal, examining how bright should the laser be and how far it needs to beat and how to be stable. But overall, the team found that existing technology can handle. In this scenario, the satellite will guide the laser to the telescope mirror, and the side camera will follow the light and any material changes, allowing the telescope to be adjusted as needed.
Researchers are still studying certain aspects of logistics of such a system, but in the future this method can help to reduce the cost of large segmented telescopes.