• Question: how far can the best telescope reach into space?

    Asked by the josh to Susan on 17 Jun 2015.
    • Photo: Susan Cartwright

      Susan Cartwright answered on 17 Jun 2015:

      The most distant galaxies we see appear to have redshifts of about 12 (though this is an approximation), meaning that the light from them was emitted only about 600 million years after the Big Bang (compared to the present time of 13.7 billion years after the Big Bang). Exactly what distance this corresponds to is a bit complicated, because it depends on exactly how you define distance and what cosmology you assume. A reasonable approximation would be about 33 billion light years.

Comments