Last night was the first of the summer's supermoons. The moon did not disappoint.
— stefanie bari (@stefaniebari) July 13, 2014
— New York City Alerts (@NYCityAlerts) July 13, 2014
— Inga Sarda-Sorensen (@isardasorensen) July 13, 2014
"Supermoon is a situation when the moon is slightly closer to Earth in its orbit than on average, and this effect is most noticeable when it occurs at the same time as a full moon. So, the moon may seem bigger although the difference in its distance from Earth is only a few percent at such times.
It is called a supermoon because this is a very noticeable alignment that at first glance would seem to have an effect. The 'super' in supermoon is really just the appearance of being closer, but unless we were measuring the Earth-Moon distance by laser rangefinders (as we do to track the LRO [Lunar Reconnaissance Orbiter] spacecraft in low lunar orbit and to watch the Earth-Moon distance over years), there is really no difference. The supermoon really attests to the wonderful new wealth of data NASA's LRO mission has returned for the Moon, making several key science questions about our nearest neighbor all the more important."
The next supermoons are on August 10 and September 9.