'Accessing delta_ut1_utc should try to get it from IERS
(closes #1924 partially)'

def test_delta_ut1_utc(self):

    t = Time('2012-06-30    12:00:00', scale='utc')
    assert (not hasattr(t, '_delta_ut1_utc'))
    assert allclose_sec(t.delta_ut1_utc, (-0.5868211000312497))
    assert allclose_sec(t._delta_ut1_utc, (-0.5868211000312497))
