The idea of finding a habitat for humanity, other than the Earth, has grown rapidly in recent years. Astronomers have found thousands (about 4,000) of confirmed exoplanets in different parts of the universe. In addition to that, there is an abundance of potential candidates that need further research before concluding anything about their status. Most of these distant bodies are detected through their ‘Transits’ (an instance when a planet momentarily blocks the light of its star). Despite the fact that these events give some basic knowledge about the planet, a lot of vital information (traces of water and Oxygen) can be extracted through advanced tools.
Bigger telescopes with light-gathering mirrors offer an ideal solution in this regard. Scientists are now trying to design such telescopes. For example, Segmented telescopes will have a number of small mirrors that can be joined together to form a very large telescope once it is launched into space. The James Webb Space Telescope of NASA is a segmented primary mirror with 18 hexagonal segments. According to a report, engineers are designing the next-generation telescopes to cater as much as 100 segments. Having said that, it is easier said than done as several technicalities are attached to these telescopes.
One of the massive challenges faced by these segmented telescopes is to keep the segments stable and point them collectively towards an exoplanetary system. The idea is to equip the telescopes with Coronagraphs to determine the difference between the light emitted by the star and the light given off by an orbiting planet. The problem with this approach is that the slightest defect in a part of the telescope can affect the measurements of a coronagraph.
In order to solve this issue, the engineers from MIT proposed that assisting spacecraft should fly with these bigger telescopes. The sole responsibility of this spacecraft will be to act as a ‘guide star’ for the large telescope. It will do that by providing a steady, bright light (laser) near the target system, which will allow the telescope to keep itself stable. Recent research showed that the development of such a laser guide star is very much possible with today’s technology. Ewan Douglas, the Lead Author of the paper who works in the Department of Aeronautics and Astronautics at MIT, talked about the feasibility of this project by saying,
“This paper suggests that in the future, we might be able to build a telescope that’s a little floppier, a little less intrinsically stable, but could use a bright source as a reference to maintain its stability.”