To make the best telescope, you want it to be big, and you want it to be clear of the Earth's atmosphere. That's why all the best telescopes are located on mountaintops, where most of air's disturbance is down below. Space telescopes are great, but there's an advantage to being able to just walk out and maintain or upgrade it.
Maybe the best of both worlds is on another world - the Moon.
NASA-funded researchers recently published a study in the journal Nature on the perfect combination of materials that could be used to create a mirror on the Moon. We're talking big; more than 20 meters across. On the Moon, there's none of that pesky atmosphere to obscure the view.
The mirror would consist of a large disc-shaped mesh on the surface of the Moon. A silver-coated liquid would be poured onto the mesh, which would then be rotated. By turning the liquid at exactly the right speed, it would spread out to coat the entire mesh, forming a perfect reflective surface. Surface tension would stop the droplets of liquid from falling between the holes in the mesh.
Although the researchers are planning for a 20 meter telescope, a 100
meter aperture is theoretically possible. A telescope this large would be capable of observing objects 1,000 times fainter than the next generation James Webb Space Telescope. It would look right back to the earliest moments of the Universe after the Big Bang.
Getting the telescope to the Moon and setting it up is going to be a problem, but this mission would dovetail nicely with the new Vision for
Space Exploration, which includes putting humans back on the Moon.
Astronauts would be critical to constructing the telescope, fine tuning its operations, and maintaining it when it fails.
Researcher Ermanno Borra acknowledges that the day we see a telescope on the Moon is a long way off, "however, if we hadn’t found the solution described in our article in Nature, it would have meant the end of the whole project."
We're glad they figured out a solution. Now, let's see it on the Moon.
Previous coverage here on Wired.
