Depends on how much they know about Earth. If you mean detect our star and detect that there is an Earth sized planet orbiting it, you need to give them access to some really gigantic telescope.
You'd get lost even if you were moved to some other part of our own galaxy - none of the stars would be familiar. You might or might not see some of the same gas clouds, but from a different angle so they wouldn't look the same. You'd need very detailed knowledge of the galaxy.
But if you permit them to have records of detailed observations from Earth - and then to use those to figure out where Earth is in the galaxy - perhaps they got there in a space warp drive and want to find their way back - I think they'd have a chance. That is so long as they were well prepared in advance.
It would be enough information to know the co-ordinates and pulse rates of all the pulsars visible from Earth. Or indeed a selection so long as you can spot some of the same ones. This then can be used as a kind of GPS to locate Earth.
You'd get lost even if you were moved to some other part of our own galaxy - none of the stars would be familiar. You might or might not see some of the same gas clouds, but from a different angle so they wouldn't look the same. You'd need very detailed knowledge of the galaxy.
But if you permit them to have records of detailed observations from Earth - and then to use those to figure out where Earth is in the galaxy - perhaps they got there in a space warp drive and want to find their way back - I think they'd have a chance. That is so long as they were well prepared in advance.
It would be enough information to know the co-ordinates and pulse rates of all the pulsars visible from Earth. Or indeed a selection so long as you can spot some of the same ones. This then can be used as a kind of GPS to locate Earth.
About the Author
Robert Walker
Writer of articles on Mars and Space issues - Software Developer of Tune Smithy, Bounce Metronome etc.Studied at Wolfson College, Oxford
Lives in Isle of Mull
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