3C48

3C48 was the first source in the Third Cambridge (3C) radio survey for which an optical identification was found (by Allan Sandage in 1960). The object was a blue quasi-stellar object at the following coordinates:

01 37 41.3 +33 09 35 (J2000 astronomical coordinates)

Later observations showed that this object was at a redshift of z=0.367, implying that it was so far away that light (and radiowaves) from it took billions of years to reach the Earth.