Total lunar eclipse coming soon!

(EDIT: I apparently still struggle with reading the calendar.  The eclipse occurs on the *end* of Good Friday, not the beginning, though that will depend on your location.  For North Americans, it will be Saturday morning.  Pacific Islanders east of the date line will see it begin in the evening of Good Friday.)

It will be somewhat disappointing, in that it will be the shortest lunar eclipse of the century (with totality lasting a mere 4 minutes 43 seconds), but as it falls on Good Friday for Christians and the start of Passover for Jews, this “blood moon” has managed to weird out a fair number of people.  But it’s just coincidence that this Paschal Moon will go into eclipse.  But a beautiful one!  This eclipse is the counterpart to the total solar eclipse seen in the Faroe Islands and Svalbard a couple of weeks ago, and will be best visible from the opposite side of the planet — so this one is centered neatly on the Pacific.  Lunar eclipses are visible from a much broader area than solar eclipses, though, so if the Moon is up during the eclipse, you will see the event.  Europe and Africa will miss out completely, but Australians and Indonesians and Chinese and Mongolians and Koreans and Japanese and Siberians will get to see the eclipse in the evening, folks in the central Pacific (like Hawaii) will see it in the middle of the night, and for folks in the westernmost parts of North America, it will occur in the morning.  South Americans and people in the eastern half o North America may see bits of the eclipse before the Moon goes down, but will miss totality.

And that actually gives us a great opportunity!  I’m too far east to see the total phase of the eclipse, but if the clouds cooperate I will get to see a fair bit of the partial phase, at sunrise.  A lunar eclipse always occurs at full moon, when the Moon is directly opposite the Sun in the sky.  Because of course it does — it’s the Earth’s shadow falling upon the Moon, after all, so an eclipse only happens during something called a “syzygy”.  And if this is happening at sunrise or sunset, you can see the whole thing since thanks to our atmosphere’s optical characteristics, you get to see the Sun and Moon for a little while before they come up and after they go down — the air refracts the light just a teensy bit around the horizon, just enough that if the syzygy is happening at sunrise or sunset, you can actually see both of them.  And there’s a bonus: the Moon will be sitting in the Earth’s shadow.  I mean, duh, of course it will, but did you ever notice you can see the Earth’s shadow through the atmosphere?

You can!  It’s called the Belt of Venus (even though Venus never appears in it) and it’s a bluish gray band in the sky below a pink band below the normal daylight colored sky.  You can see it opposite the Sun on a clear day at sunset, and it’s the Earth’s shadow, darkening a portion of the atmosphere.  Remember — the Sun at this time is actually below the horizon.  You only see it above the horizon because of refraction bending its image around the limb.  Weather permitting, you can see the Belt of Venus every day.  But of course the Earth’s shadow extends an awful lot further than that, far enough for the Moon to stand in it, but you only get to see that during a lunar eclipse.

So set your alarm clock!  Here are the times for the eclipse, given in UTC; convert to your local time to determine whether or not you get to see the eclipse:

P1 (first contact with penumbra) – 09:01:27 UT

U1 (first contact with umbra, start of partial phase) – 10:15:45 UT

U2 (total phase begins) – 11:57:54 UT

U3 (total phase ends) – 12:02:37 UT

U4 (last contact with umbra; partial phase ends) – 13:44:46 UT

P4 (last contact with penumbra; eclipse ends) – 14:58:58 UT

Beautiful eclipse animations (note: the color of the Moon during an eclipse is highly variable and dependent on the Earth’s atmosphere — it may be darker or lighter than what is depicted here)

Charts showing eclipse depth (very shallow) and area of visibility

Get timings for major cities


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