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Last of season’s 3 full moons on March 5

Photo via Flickr user Bruce Fingerhood

Tonight is Mar 05, 2015

Moon Phase Courtesy U.S. Naval Observatory

Photo top of post via Flickr user Bruce Fingerhood

Tonight’s moon might look full, but the crest of the moon’s full phase comes on March 5, 2015 at 18:05 Universal Time, or 12:05 p.m. Central Standard Time. This March full moon will be the third of 2015. It’ll be the Northern Hemisphere’s third and final full moon of winter and the Southern Hemisphere’s third and final full moon of summer. So full moon is tomorrow. But tonight, no matter where you live on Earth, look for the moon to look plenty full as it shines from dusk until dawn.

In the Northern Hemisphere, we often call this full moon the Sap Moon, Crow Moon, Worm Moon or Lenten Moon. For the Southern Hemisphere, this March full moon just misses being the Harvest Moon – the closest full moon to the autumn equinox. The full moon on April 4 occurs a little closer to the March equinox, so it narrowly beats out the March 5 full moon for the Harvest Moon title in the Southern Hemisphere.

The upcoming equinox will take place on March 20, 2015. It’s the spring equinox for the Northern Hemisphere and the autumn equinox south of the equator. There will be an eclipse of the sun on this equinox, about two weeks from now, when the new moon covers the sun and blots it from view.

In addition, some will call this March 5 full moon a micro-moon or mini-moon because it will be the smallest full moon of 2015. We elaborate on that distinction in tomorrow’s post.

Who will see the moon at the instant it is most full? Not the Americas, Greenland, far-western Europe or far-western Africa. All of us in those places will be on the daytime half of the world as the moon turns precisely full. When the moon rises over our horizons after sunset on Wednesday, March 4, it’ll be waxing … though it’ll look full, and people will call it a full moon. And when we watch the moon rising in the east as darkness falls on Thursday, March 5, it’ll be waning … though it’ll still look plenty full.

Today's moon - March 4, 2015 - via Cristina Voicu. Given the time this was posted today at EarthSky Facebook, Cristina is likely in Europe ... or further east.  Today's moon looks full, but full moon is March 5.  Thanks, Cristina!

Today’s moon – March 4, 2015 – via Cristina Voicu. Given the time this was posted today at EarthSky Facebook, Cristina is likely in Europe … or further east. Today’s moon looks full, but full moon is March 5. Thanks, Cristina!

Day and nights sides of Earth at the instant of the March 2015 full moon (2015 March 5 at 18:05 Universal Time) Image credit: Earth and Moon Viewer

Day and nights sides of Earth at the instant of the March 2015 full moon (2015 March 5 at 18:06 Universal Time) Image via Earth and Moon Viewer

Astronomically speaking, the moon reaches full phase at the instant that it is most directly opposite the sun as the moon orbits Earth.

If you live in North America, look at it this way. You might prefer to see the moon at the instant of full moon next month, in April 2015. That’s because the full moon will be swinging right through the Earth’s umbra (dark shadow) before sunrise on April 4 in this part of the world. Yes, a good portion of North America gets to see the April 2015 total lunar eclipse, or at least a partial lunar eclipse, before sunrise April 4. Eastern Asia, Australia and New Zealand will see the total lunar eclipse after sunset April 4.

Shortest total lunar eclipse of the 21st century on April 4, 2015

So Earth’s shadow misses the moon this month, only to swipe across the moon’s face in April 2015. No matter where you live worldwide, Earth’s shadow won’t diminish the light of the March 2015 full moon!

By the way, the planets Uranus and Venus are in conjunction on March 4.  They are separated by just 0.1 degree.  Read more about the conjunction.  Photo by Abhinav Singhai Photography.

By the way, the planets Uranus and Venus are in conjunction on March 4. They are separated by just 0.1 degree. Read more about the conjunction. Photo by Abhinav Singhai Photography.

Bottom line: Full moon comes on March 5 at 18:05 Universal Time, or 12:05 p.m. Central Standard Time. This March full moon is the third of 2015. Northern Hemisphere’s final full moon of winter. Southern Hemisphere’s final full moon of summer.