The full moon will come during the night tonight (November 27-28, 2012) for us in North America, and it comes with some interesting features. That is, in 2012, the November full moon gives the world its smallest full moon of the year – and in North America, a subtle, penumbral eclipse of the moon before sunrise November 28. Meanwhile, those in the world’s Eastern Hemisphere – Europe, Africa, Asia, Indonesia, Australia and New Zealand – will see this penumbral lunar eclipse after sunset November 28. There’s more about who will see what at the bottom of this post.
The eclipse computer provided by the U.S. Naval observatory lets you find out the local times of the eclipse for your time zone. You do not have to translate Universal Time (UT) into your time. Nonetheless, we list the eclipse times in Universal Time (for Wednesday, November 28):
Penumbral eclipse begins: 12:15 Universal Time
Greatest Eclipse: 14:33 UT
Penumbral eclipse ends: 16:51 UT
Although the penumbral eclipse lasts – technically speaking – for over four and one-half hours, you’re only likely to notice a slight shading on the north side of the moon for up to an hour or so, centered at greatest eclipse (14:33 Universal Time). Generally, at least 70% of the moon’s diameter must be immersed within the Earth’s penumbral shadow before the eclipse becomes noticeable. At greatest eclipse on November 28, the penumbral shadow will cover nearly 92% of the moon’s diameter.
What can you expect to see during the November 28, 2012 penumbral lunar eclipse? First, here’s what you will not see. You won’t see a dark bite taken out of the moon by Earth’s shadow. And you won’t see the moon turn blood red as during a total eclipse of the moon. A penumbral eclipse is more subtle than either of these. At the central part of the eclipse, you’ll see a dusky shading covering about 90% of the moon’s face. By the way, that brilliant planet near tonight’s moon is the king planet Jupiter. The moon and Jupiter will be even closer together tomorrow night.
So, before you set your alarm clocks, consider yourself forewarned. A penumbral lunar eclipse is not nearly as stark and obvious as an umbral eclipse of the moon. During an umbral lunar eclipse, the moon passes through the umbra – the Earth’s dark, cone-shaped shadow. During a penumbral eclipse, the moon passes through the light penumbral shadow surrounding the umbra. (See feature diagram at top.) Your best chance of noticing any penumbral shadow on the moon’s surface is at mid-eclipse (greatest eclipse) in a dark sky not obscured by dusk or dawn.
Note the world map below. The farther west and north you live in North America, the better your chances of catching the subtle shadow on the moon before dawn on November 28. The farther east or north you are in the world’s Eastern Hemisphere, the better are your chances of seeing the penumbral eclipse after nightfall on November 28.
People in Alaska, Hawaii, New Zealand, Australia, and most of Asia will be on the correct side of Earth to see the eclipse. The western U.S. and Canada will also catch part of it.
So Alaska, Hawaii, New Zealand, Australia, and east Asia will see the entire eclipse on November 28. For western Canada and the western U.S. moonset will happen sometime after mid-eclipse. For eastern Canada and the eastern U.S., the eclipse will begin after moonset. No eclipse on November 28 for you in the east … sorry.
Actually, the eclipse would be much more exciting to watch if you could view it from the moon. At or near the moon’s north pole, you’d see our planet Earth covering about 90% of the sun’s diameter. As you go farther south on the moon, the Earth would cover less of the sun. At the southernmost regions of the moon, you’d see no eclipse at all.
Bottom line: The full moon of November 28, 2012 is the smallest full moon of the year and will be darkened by the very subtle penumbral shadow of Earth during the night tonight (night of November 27-28), or before dawn for North America. Cloudy where you are? Just can’t get up that early? Don’t worry. You can still see the moon boldly lighting up the night sky from dusk until dawn for the next couple of nights! By the way, in North America, we often call the November full moon the Frosty Moon or Beaver Moon.