How easy is it for ET to observe the Earth
Astronomers have identified nine planets from which intelligent aliens could potentially be watching us.
While much work has been done over the years to look for signs of intelligent life out there in the cosmos, there has been little consideration of the possibility that someone might be watching us.
In a recent study, scientists from Belfast set out to determine where the best vantage points would be for an extraterrestrial civilization who wanted to observe what we were up to.
The research involved identifying the parts of the sky from which the planets in our solar system could be seen passing in front of the Sun from the perspective of a distant observer on another world.
It turned out that the rocky terrestrial planets such as the Earth and Mars would be the easiest to spot.
"Larger planets would naturally block out more light as they pass in front of their star," said Robert Wells from Queen's University Belfast. "However the more important factor is actually how close the planet is to its parent star. Since the terrestrial planets are much closer to the sun than the gas giants, they'll be more likely to be seen in transit."
The scientists ultimately detected 68 extrasolar planets from which at least some of the planets in our solar system could be observed and at least 9 that would be "ideally placed" for observing the Earth.
None of these planets however are currently believed to be habitable.