2011 June Solstice 2011-6-21 17:16 UTC.
aa.usno.navy.mil/data/docs/Ear ...

2011 Summer Solstice Doodle (First Day of Summer) is by Takashi Murakami.
guardian.co.uk/technology/2011 ...

static.guim.co.uk/sys-images/G ...

"First Day of Summer, Doodle by Takashi Murakami, 2011."
google.com/search?q=Summer+Sol ...

google.com/logos/2011/murakami ...

google.com/logos/2011/murakami ...

The first hit of 1st search string mentioned:
en.wikipedia.org/wiki/Summer_s ...

And from 2nd search:
en.wikipedia.org/wiki/Winter_s ...

Yahoo.com noticed that from the summer side:

blazomania.com/2011/06/21/goog ...