Listening to the Universe from the Far Side of the Moon

Perhaps one of the best reasons to return to the Moon will be the boon to astronomy. Without an atmosphere, an observatory the Moon won’t have to peer through an obscuring atmosphere, but people will still be able to walk over and fix it – and even upgrade it – into the future. It’s the best of both worlds. It’s no surprise then, that engineers are working on plans for lunar observatories. When the next wave of astronauts return to the Moon, they’ll be bringing their ‘scopes.

NASA recently selected a series of 19 proposals for lunar observatories, including one suggested by a team from MIT. This observatory would help astronomers study the “Dark Ages” of the Universe, when the first stars and galaxies, and even dark matter formed.

During the first billion years after the Big Bang, there were no stars and galaxies, only opaque hot gas. When the first stars could finally form, their radiation helped ionize this gas and make it transparent. You could finally see in the Universe. It was also in this time that the mysterious dark matter formed from the soup of elementary particles, serving as a gravitational structure for matter to clump around.

The MIT proposal is called the Lunar Array for Radio Cosmology, and it’s headed by Jacqueline Hewitt, a professor of physics and director of MIT’s Kavli Institute for Astrophysics and Space Science.

It would consist of hundreds of telescope modules spread over a 2 square km area designed to pick up very-low-frequency radio emissions. Automated vehicles would crawl across the lunar surface deploying the telescopes.

The time of the Dark Ages is impossible to view from Earth because of interference from our high atmosphere as well as the background radio emissions coming from all directions. But the far side of the Moon is shielded from the Earth’s radio barrage. There it would have a clear, quiet view of the most distant Universe.

There’s another advantage with building a long-wavelength radio telescope on the complicated surface of the Moon; it’s much easier than building a fragile mirror for an optical telescope. The low wavelength radio waves don’t require a high degree of accuracy, so it will be a good test for working on surface of the Moon. Even if some of the individual modules aren’t working, or clogged with lunar dust, the full observatory will still be able to collect data.

The telescope would also be used to study coronal mass ejections coming from the Sun, and accurately measure the space weather passing through the Earth-Moon system. This is what the astronauts will use to check their local weather.

MIT will be working on a one-year study to develop a further plan for the array. If it’s actually chosen for development down the road, construction would begin after 2025 at a cost of more than $1 billion.

Original Source: MIT News Release

9 Replies to “Listening to the Universe from the Far Side of the Moon”

  1. While they’re listening for the Dark Ages, they could tune up the dial a little and see if any alien life is broadcasting they’re virsion of “I Love Lucy.” Never know… they might have as bad a programing schedule as we do.

  2. To Jeysey Jim

    Hi Jim
    The Moon is synchronously locked to the Earth, that is, the Moon takes 28 days (roughly) to orbit around the Earth, but it also takes 28 days (roughly) to rotate on its own axis. Hence, we on Earth can only see the same side (the nearside) of the Moon all year around, and never get to see the farside. So, in effect, from our perspective, you are in a way correct in saying that the Moon doesn’t rotate (it just looks that way from Earth). Thus, putting a radio telescope on the farside of the Moon means that they would never actually come into line of sight of earth’s interfering radio waves (not all, mind you).
    On another note, the moon’s phases aren’t caused by the Moon rotating at all, but are in fact produced by the position it is in its orbit around the Earth — and, most importantly of all, its position relative to the Sun. For example, this month’s total lunar eclipse is produced because the Moon’s position will lie opposite that of Earth and the Sun (that is, the Earth will lie directly between the Moon and the Sun). So, Sunlight will be striking the Moon’s nearside face ‘nearly’ head on (thus we’ll see a full moon at first from Earth), before its orbit (the moon’s orbit) then starts to move into the Earth’s shadow. This kind of dance between the Earth, Moon and Sun is happenning all year around, which is why we only get to see the phases occurring every month as the Moon moves in its orbit and the Sun’s light strikes it accordingly.
    Hope this helps?
    John –

  3. How is the “far” side of the Moon shielded from the “Earth’s radio barrage” any more than the “near” side?

    Both sides of the Moon face the Earth the same amount of time as it rotates each lunar month (causing the Moon’s phases). The “radio barrage” statement implies either that the Moon doesn’t rotate or that being in the dark somehow protects the “far” side from the Earth’s radio transmissions. Both of which are incorrect.

  4. Wrong. The far side of the moon is the far side… It never faces earth. You can’t see it from earth. This is why it can shield the radiotelescope. Man had the first glimp of this side in 1959 with the soviet Luna 3.

  5. The radio spectrum up to aprox. 30 megahertz (AM radio and shortwave) would be able to be heard on the dark side of the moon fairly easily, but in much lower signal strength. Higher frequencies could be heard via being bounced off of other objects, like planets or asteroids. But it would still be much quieter than any other permanent location in the solar system

  6. I’m concerned that transmissions from the telescope station on the moon will interfere with those already bombarding the “light side” of the moon since no transmissions of “live feed” can be transmitted from the telescopes actual location on the “dark side” I’m assuming a feed line or conduit (truck line) will tunneled or ran to the “light side” for transmission to earth. Am I correct?

Comments are closed.