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Fraser
2004-Sep-16, 04:51 PM
SUMMARY: Researchers from Australia have demonstrated that an observatory in Antarctica can produce images of the sky several times better than telescopes at mid latitudes. A team of astronomers from the University of New South Wales made observations using a robotic telescope in an observatory called "Dome C" on the Antarctic Plateau, 3250 metres (10,600 feet) above sea level. They found that the sharpness of images was three times better than the best sites used by astronomers in other locations. An 8m telescope here would function like a 25m telescope anywhere else - at a fraction of the cost of a space-based observatory.

What do you think about this story? Post your comments below.

lswinford
2004-Sep-16, 08:04 PM
I had an uncle who spent four winters at the south pole station. He told of the incredible distances a person could see, when the wind wasn't blowing snow around. But I never once heard him talk about the stars, even though he and the others lived in boxes under the ice.

The problem with spending too much on telescopes in antarctica is that there would be less than half the time the telescope could be used, simply from the day/night seasonality. Maybe the scope is high enough to get above the snowstorms that would certainly obscure things more than a little, but the available viewing time, in total would be terribly limited. Practicalities of remotely maintaining a large scope in that harsh environment are enormous. So I think they did about as well as anyone could and had they gotten much more ambitious with bigger equipment there would have been more disappointments, and therefore fewer successes.

Oh, I asked my uncle if he wanted to go back to do more sessions and he said he couldn't. It wouldn't be permitted because he had reached his radiation exposure limits. Although, he is now retired and living in a warm state, I'm sure he wouldn't be terribly interested for other reasons today. B)

anneliese
2004-Sep-20, 03:31 AM
Originally posted by lswinford@Sep 16 2004, 08:04 PM
The problem with spending too much on telescopes in antarctica is that there would be less than half the time the telescope could be used, simply from the day/night seasonality.
but we have the same problem with any scope on Earth really, when you think about it... the productivity for the winter time would be huge, round the clock time available! the long summer would give the opportunity for any work needed after the harsh winter conditions... I have always been a fan of the idea of a big telescope in Antarctica, and not just because i have always wanted the opportunity to work there!! :D

kashi
2004-Sep-20, 05:12 AM
I suspect the weather conditions in the winter would make much of the time unusable for astronomical observations.

Michael Ashley
2004-Sep-21, 06:44 AM
Hi folks, Michael Ashley here, one of the coauthors on the Nature Letter that is being reported on Universe Today.

When the sun is up, you can observe in the infrared and submillimeter, thereby making maximal use of the time. The viewing time should be 75%.

Conditions in winter at Dome C are perfect for astronomy: nice and cold, few clouds, almost zero wind, no snowstorms, stable atmosphere. The snowstorms that the South Pole experiences are essentially absent at Dome C due to the much lower winds.

For much more information see my website http://www.phys.unsw.edu.au/nature and the links therein.

Cheers, Michael
University of New South Wales
Department of Astrophysics

antoniseb
2004-Sep-21, 06:12 PM
Originally posted by Michael Ashley@Sep 21 2004, 06:44 AM
Conditions in winter at Dome C are perfect for astronomy: nice and cold, few clouds, almost zero wind, no snowstorms, stable atmosphere.
Hi Michael,

How close to the horizon can objects be viewed for serious astronomy efforts? What fraction of the sky is really observable from there?

Would this be an appropriate location for one or more of the next generation telescopes that are ten times the light gathering power of the Keck instruments in Hawaii [or perhaps even the proposed but un-funded OWL].

The other question I had was that the images shown in the article demonstrated improved seeing from Dome C, but it wasn't clear from the captions whether adaptive optics could also eliminate that fuzziness.

Michael Ashley
2004-Sep-22, 04:07 AM
Hi antoniseb,

The closer to the horizon you go, the worse the seeing becomes, and the worse the transmission losses. So, astronomers try to observe as close to the zenith as possible. However, if pushed, you can go to altitudes of only 30 degrees, and if the observation is particularly important and time-critical (e.g., a gamma ray burst, or a transit of something) you might go down as low as 5 degrees, or even lower.

Dome C is an excellent location for a next generation telescope. The low winds and zero seismic activity are very helpful when building large structures. We are aiming to deploy a 2-m class telescope first, to prove that we can work at Dome C as expected.

Adaptive optics at a mid-latitude site can help to some extent, but it has limitations. Foremost amongst these it that it only works at infrared wavelengths at mid-latitude sites (it would work in the visible at Dome C, however). Also, the region of sky that you can correct with single-star adaptive optics is very limited (just arcseconds in diameter).

Cheers, Michael
Dept. of Astrophysics
University of New South Wales

anneliese
2004-Sep-22, 05:38 AM
:P yay!! :D

zephyr46
2004-Sep-22, 05:44 AM
A telescope would compliment Amanda II (http://amanda.uci.edu/) beautifully.

Would the conditions improve infrared telescopes as well?

What is the location (http://www.phys.unsw.edu.au/nature/#14)? :rolleyes:

Is there any point in building on Mt Vinson Massif
or Kirkpatrick, does altitude still help in Antartica?

antoniseb
2004-Sep-22, 08:42 PM
Originally posted by Michael Ashley@Sep 22 2004, 04:07 AM
Dome C is an excellent location for a next generation telescope.
Has your team been in touch with anyone from TMT, GSMT, ELT, or VLOT [or perhaps even OWL] about the location? It might not occur to them without some kind of proactive input.

Also, how broad is the area? Is the good seeing available from thousands of square kilometers, or just an isolated area?