[time] What is the `zero` value for time.Time in Go?

In an error condition, I tried to return nil, which throws the error:

cannot use nil as type time.Time in return argument

What is the zero value for time.Time?

The zero value for time.Time is 0001-01-01 00:00:00 +0000 UTC See http://play.golang.org/p/vTidOlmb9P

You should use the Time.IsZero() function instead:

func (Time) IsZero

func (t Time) IsZero() bool
IsZero reports whether t represents the zero time instant, January 1, year 1, 00:00:00 UTC.