When I view from off the Earth, the time reads "UT". What does this mean?


    UT is short for "Universal Time". This is the same thing as Greenwich Mean Time, and is the time in London, England (not accounting for daylight savings time). Universal Time is used as a standard reference time for astronomical events by astronomers around the world. When you are viewing from a location off the Earth, your old "time zone" does not really apply, so Starry Night uses Universal Time.


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      Roy Levien

      You say that UT means GMT. This is incorrect. GMT (or, more precisely, UTC) is kept within 0.9s of UT (UT1), but always differs by a small amount. So, is your "UT" really UTC or is it, in fact UT, in which case it is not GMT (UTC)?