The darkest place on the planet would be somewhere way out in the middle of the Atlantic or Pacific ocean, a thousand miles away from the nearest city and its lights. But it is hard to locate a telescope on a boat. So astronomers look for the darkest place on land.
The following article talks about a place in Scotland that is about to be certified as the third dark-sky park on the planet:
You do not need rocket science to explain why the forest park is special, says Steve Owens, the UK national co-ordinator of the International Year of Astronomy and one of tonight's three inspectors. It's simple: high-quality darkness depends on an absence of light. Light pollution from sodium lamps in the city “is a terrible spoiler for astronomers”, he said. “On the clearest night in London you might be able to pick out only 200 stars.”
In Galloway Forest Park about 7,000 fill the sky. Weather permitting.
The park is located here:
There are two other dark-sky areas certified by the International Dark-Sky Association (Darksky.org). They are
Natural Bridges, Utah, and Cherry Springs State Park, Pennsylvania.
Here are some other places that, though not certified, are very dark:
This brings up the obvious question - what is the darkest place on the planet? This is actually a tricky question, because it depends on many things, including the amount of moonlight the site receives. After all, if the moon is always out it spoils the darkness, as described in this article:
To make astronomers happy we want to have as dark a sky as possible. We already learned that the sun should be more than 18° below the horizon for that and we have to stay away from the light pollution of civilization. But there is one more thing to take care of - the Moon. With a bright Moon in the sky you will see fewer stars and no Milky Way or other dim objects. Who gets the most hours of astronomically dark skies without the Moon? The 2009 figures (variations are possible in other years due to the orbit of the Moon) show the equator with a maximum of 1721 hours. At 80° North it is just 825 hours and the minimum for all latitudes is 807 hours (this amounts to just little over a month) at 80° South. So Antarctica isn't all that dark even in winter! Add to that the fact that it is covered in snow and ice which lightens up the landscape and that there may be some aurora brightening up the sky this is the least-dark place on Earth. By contrast the equator is the darkest place especially as there is often some dense vegetation which seems to swallow what little light is left.
So Antarctica is definitely dark when the moon isn't out, like the ocean, because it is so remote. But it is cold, inaccessible to most people and has a moon problem. Therefore Dartmouth has a telescope in South Africa, in a place claimed to be one of the darkest on earth:
Fesen, one of Dartmouth's SALT project leaders, said that the location in South Africa, on a hilltop near the tiny town of Sutherland, is one of the darkest places on earth. A dark environment facilitates the telescope's ability to gather light, allowing it to "see" deep into space.
Here is the location:
If you zoom in a little you can see just how remote it is.
You can find other dark places by looking where the biggest telescopes are located:
[[[Jump to World Record #107 – The strongest magnets in the world]]]