Plan calls for robots to construct modular telescopes in space
The largest optical telescope on Earth is currently the Gran Telescopio Canarias, with a collective reflective surface 34 feet across. In space, the largest optical telescope is the Hubble Space Telescope, which does amazing work with a relatively modest 7.9-foot mirror. Size matters for optical observations, since a larger mirror means more light can be collected, meaning fainter, more distant objects can be viewed, and yet there’s obviously a huge gap between these two pieces of equipment. A new plan being developed between Caltech and the Jet Propulsion Laboratory (JPL) aims to shrink that gap by enlisting the help of robots to build us bigger telescopes in space.
Assembly without astronauts
The robotically assembled modular space telescope (RAMST) concept would have autonomous robots building our biggest telescopes for us. It’s not that humans are bad at building big telescopes, as the Gran Telescopio Canarias demonstrates, but it’s hard for humans to work for the extended periods of time in space where these new, modular telescopes would actually be assembled. A robot could not only assemble the pieces, but also ride along the completed instrument to perform maintenance or upgrades down the line without needing to worry about pesky concerns like food or life-support while it waits.
The telescopes would need to be assembled in space to get around the biggest limitation on space observatory size today— size itself. The larger a telescope is, the bulkier and heavier it is, which makes it that much harder to lift off the ground and deploy into space. To deal with this, the modular portion of the RAMST concept comes into play, as smaller components could be sent to space across multiple missions, collected and then built once all the pieces were successfully delivered to orbit (or further from Earth, if need be.) The fact that our largest optical scope on Earth is already the product of many smaller mirrors acting as one points to the feasibility of such a design.
Why go through all this trouble though? If we’ve already got huge, modular and at least partially upgradable facilities on Earth, what’s the advantage of dealing with a robot building a similarly-sized scope in space? Any telescope on Earth will be fighting against noise and interference from our atmosphere. Even the sky on a clear day has enough air molecules to warp or scatter light coming from distant galaxies, limiting what kind of pictures we can capture from the ground. Terrestrial telescopes are also tied to a specific location on the planet, and so timing becomes an issue since your telescope might be on the wrong side of the planet at the moment you want to see something. A telescope away from the planet can avoid both these problems, and would extend the range and accuracy of what we could observe in space. And it’d mean we’d have more cool robots.
Source: Robot would assemble modular telescope — in space, Scienmag
