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What is the farthest thing I can see with my own eyes, and the farthest thing I can see with an amateur telescope, and the farthest-away thing the biggest telescopes on Earth can see?

The most distant object visible to the naked eye is M31, the Andromeda Galaxy, at about 2 million light-years. This is the nearest large galaxy to us, and a very bright one at that. I can't say for certain the most distant object that you can see with an amateur telescope because the size of such telescopes can vary a lot, and because it depends on the detector that you have attached to it (like your eye, film, or an electronic CCD). But you can definitely see galaxies beyond the Local Group, even with your eyes.

The most distant object known and observed with a large optical telescope is the quasar PK 1247 +3406, at a distance of 5000 megaparsecs, the time when galaxies first began to form.


Submitted by Ben (Maryland, USA)
(June 8, 1998)



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