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Small Telescopes Make Big Discoveries
Hugh Pickens writes writes "Hakeem Oluseyi, an astronomer at the Florida Institute of Technology and president of the African Astronomical Society, says his goal is to put one research telescope in every country, starting with African and Southern Hemisphere nations because there is now an amazing opportunity for small telescopes to discover and characterize new planetary systems, as well as measure the structure of the Milky Way. 'Astronomers are no longer looking at high-definition pictures but at HD movies, scanning for objects that change and for transient ones,' says Oluseyi. 'A 4-inch telescope was used to discover the first exoplanet by the transit method, where you watch the brightness vary.' Small telescopes capable to doing real science are a lot cheaper than people think. A 1-meter telescope costs $300,000 but reduce the size by 60 percent, and it falls to just $30,000. For example the Kilodegree Extremely Little Telescope (KELT) uses hardware costing less than $75,000 to look at millions of very bright stars at once, over broad sections of sky, and at low resolution to see if the starlight dims just a little — an indication that a planet has crossed in front of the star. The KELT team has already discovered the existence of a very unusual faraway planet — KELT-1b, a super hot, super dense ball of metallic hydrogen so massive that it may better be described as a 'failed star' and located so close to its star that it whips through an entire 'yearly' orbit in a little over a day."
Really? Not even trying?
As far as I understand it, the primary reason to send telescopes into space is because the atmosphere is opaque to certain wavelengths. There's also distortions caused by the atmosphere for other wavelengths, but we've found number crunching techniques that are cheaper than sending them out into space because on the ground we can build ridiculously sized telescopes like the 2800 ton E-ELT.
Live today, because you never know what tomorrow brings
Actually we are using number crunching to improve images. The air waves and wiggle kind of like the light you see at the bottom of a pool (it actually different because the atmosphere's upper boundary isn't the source of the moving refraction, but the effect is pretty much the same. It makes it hard to get a clear image especially if you average the image out over long exposures. The mirrors on modern terrestrial telescopes have thin mirrors and actuators that deform the mirror. So they slightly deform the mirror to accommodate the fluctuations in the atmosphere so the two cancel out. They way they measure the atmosphere, is by shooting a laser straight out from the telescope to create an artificial star upon which to focus.
Yes computers are used to analyze the image to control the deformation, but its the shifting mirror that fixes the unfocussed image.
diameter is more important than length
Modern telescopes with the ability to compensate for atmospherics are now so good they can work at higher resolution than even the Hubble could manage above the atmosphere. That is one reason they decided to end the Hubble's service. Better images are possible from the ground now at much reduced cost vs the Hubble. Or in other words they can be almost completely effective to remove the ill effects of the atmosphere. Then the limit to resolution is simply the diameter of the instrument which on the ground can be larger than the Hubble.
1) searching for exoplanets is hot at the moment, it's a selling point.
2) these smallish telescopes are in the price range of poorer nations - not of the people maybe but certainly in range of the budgets of educational institutions or local governments wanting to please their constituents.
3) the nations mentioned are poor, can't afford expensive stuff, and this may spark off general scientific interest amongst their people.
4) it doesn't make sense promoting it to rich countries, because they'll consider it "too cheap" or "not good enough" or whatever.
So yes, one does have to do with another. Whether a lot of new discoveries will come out of them remains to be seen but with more eyes pointing towards the sky, the overall chance of making discoveries is definitely increasing.
There was an incredibly relevant article[1] in Analog Science Fiction & Fact recently. The basic premise is that it's not just smaller research telescopes that are valuable - in astronomy, even amateur observations are incredibly valuable (often because they happen to notice things the bigger telescopes aren't pointed at). The author details a large number of findings that are rooted in observations by amateurs.
Mr. Olusevi shouldn't limit himself to just $30,000 research telescopes. He should also be trying to get $300 telescopes in backyards all over Africa.
[1] Plummer, Alan. Atlas' Apprentices: Amateur Contributions in Astronomy and Astrophysics