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Small Telescopes Make Big Discoveries

Posted by samzenpus on from the getting-small dept.

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."

13 of 37 comments (clear)

  1. Link to Firefox update? by Score+Whore · · Score: 4, Informative

    Really? Not even trying?

  2. Why not just the best observing sites? by tomhath · · Score: 2

    starting with African and Southern Hemisphere nations because there is now an amazing opportunity for small telescopes to discover and characterize new planetary systems

    One has nothing to do with the other.

    1. Re:Why not just the best observing sites? by cusco · · Score: 2

      A country is going to site the telescope in the best observing site they have available. Every country will have different capabilities and opportunities. Peru is near the equator but has high altitude and extremely dark locations. South Africa has no high altitude locations but can view much further south. Iran has neither location nor altitude, but has an enthusiastic, united population who will turn off urban lights, including street lights, on important viewing dates.

      --
      "Think about how stupid the average person is. Now, realise that half of them are dumber than that." - George Carlin
    2. Re:Why not just the best observing sites? by wvmarle · · Score: 3, Insightful

      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.

    3. Re:Why not just the best observing sites? by Dr.M0rph3us · · Score: 2

      It's true that the northern hemisphere had the majority important telescopes... several decades ago. Actually, interest in installing telescopes to study the southern sky began as early as 1820, when Great Britain founded the Royal Observatory at the Cape of Good Hope, the first scientific institution in Africa. Following a few mergers and changes, the South African Astronomical Observatory was established in 1972, now operating one of the largest telescopes in the world - a 9.2 meter reflector telescope, the SALT, completed in 2005. In 1972 Another major southern telescope was built in 1974, in Australia, at the Siding Spring Observatory, housing the AAT, a 3.9 meter telescope.

      The first modern large-scale reflector telescopes, that used photographic plates and films, were built at the beginning of the 20th century. The first telescopes having the primary mirror with a diameter larger than 1 meter were the Hale telescope (1908) and the Hooker telescope (1917), at Mount Wilson Observatory. After the vacuum evaporation coating technique was developed at CalTech, larger primary mirror diameters were possible, and for many years the 1948-built Hale reflector telescope at Mount Palomar was the largest telescope in the world having 510 cm primary mirror diameter. So far, most of the large telescopes were in the northern hemisphere.

      In 1953, a shared European Observatory is discussed for the first time, and one year later it was established that this observatory will be placed in the southern hemisphere. The ESO charter is signed (ESO is celebrating 50 years these days, btw), and in 1966 the first telescope used in Chile received its first light. Right now, ESO is operaing one of the most advanced optical instruments, the VLT, which is actually an interferometer using four 8.2 meter main telescopes and four 1.8 meter auxiliary telescopes. Plans are under way to building the EELT, a 39 meter main mirror optical/near-infrared telescope, which will be the largest telescope on Earth by the time of its completion.

      In conclusion, we have lots of world-leading telescopes in the southern hemisphere that hunt for planets using multiple techniques, including Doppler-shift spectroscopy, transit and direct imaging.

  3. Re:... and the goal is ? by Kjella · · Score: 3, Interesting

    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
  4. Re:... and the goal is ? by Genda · · Score: 4, Informative

    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.

  5. Re:I'll say it... by rubycodez · · Score: 3, Insightful

    diameter is more important than length

  6. Re:...and ground based is better now by esldude · · Score: 3, Informative

    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.

  7. The point isn't finding better sites by Benfea · · Score: 2

    People have been talking off and on about how to bring science to poorer nations that necessarily deal with very small budgets. This is more about helping people in those poorer nations (giving smart kids in those nations something to strive for) than about making science better, although it does help with science advocacy among the global population.

  8. TRAPPIST @ ESO by xof · · Score: 2

    See also TRAPPIST to Scout the Sky and Uncover Exoplanets and Comets. (TRAnsiting Planets and PlanetesImals Small Telescope) A robotic .6 meter telescope at ESO’s La Silla Observatory on the outskirts of the Atacama Desert in Chile.

  9. Not just research telescopes by dlgeek · · Score: 3, Insightful

    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

  10. Re:...and ground based is better now by Dr.M0rph3us · · Score: 2

    I'm going for a further informative note here, noting exactly how this compensation is done.

    It's entirely true that modern telescopes have the ability to compensate for most of the atmospheric effects, and this is why there are major efforts in building larger telescopes, such as the E-ELT. But for certain wavelengths, the atmosphere is almost completely opaque, making ground observations ineffective, and requiring the use of satellites for these observations. Also, light pollution is also a major problem that worsens day by day, and moonlight creates considerable problems under the atmosphere, even in a dark site.

    Since the dawn of digital image and data processing techniques, the modern telescopes and observatories are able to compensate for atmospheric extinction or absorption effects. This effect varies depending on the location and altitude, and this is why higher-ground observatories are preferred, and the local extinction curve can be very accurately measured and applied to the captured data.

    Another breakthrough was the implementation of active and adaptive optics. Active optics are used to compensate mechanical, thermal and construction limitations of larger mirrors, by using an actuator matrix on the primary, secondary or both mirrors of the telescope. Adaptive optics uses a guide star - either a natural one or an artificial one (see: sodium laser guide star), to compensate for atmospheric lensing and scatter effects. The light from the guide star is used to control the actuators on an auxiliary mirror, thus compensating for these atmospheric effects.