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Super Blue Moon eclipse on January 31

Total lunar eclipse photo taken in 2004 by Fred Espenak

The Blue Moon – the second of two full moons in one calendar month – will pass right through the Earth’s shadow, to stage a total eclipse of the moon during the nighttime hours on January 31, 2018. This full moon also caps a series of three straight full moon supermoons, whereby the full moon comes close enough to Earth to be dubbed a supermoon.

Twice in a Blue Moon in 2018!

However, if you live in North America or the Hawaiian Islands, remember that this lunar eclipse will be visible in your sky during the morning hours before sunrise on January 31.

On the other hand, if you live in the Middle East, Asia, Indonesia, Australia or New Zealand, this lunar eclipse will happen in the evening hours after sunset on January 31.

Follow the links below to learn eclipse times and more:

Eclipse times in Universal Time

Eclipse times for North American time zones

Eclipse calculators provide eclipse times for your sky

Who will see a partial lunar eclipse?

What causes a lunar eclipse?

The worldwide map below shows the day and night sides of Earth at mid-eclipse (greatest eclipse) on January 31, 2018, at 13:30 UTC. Although the greatest eclipse happens at the same instant all around the world, you must be on the nighttime side of the world to witness the moon at mid-eclipse (greatest eclipse).

Worldwide map via the US Naval Observatory showing the day and night sides of Earth at the instant of the greatest eclipse (2018 January 31 at 13:30 UTC). The shadow line at the left depicts sunrise (moonset) January 31, and the shadow line at right represents sunset (moonrise) January 31. The total eclipse lasts for about one and one-fourth hours, meaning that if you live somewhat east (right) of the sunrise line, you can still see a total or partial eclipse low in the west before sunrise (and before greatest eclipse). Or if you live somewhat west (left) of the sunset line, you can still see a total eclipse low in the east after sunset (and after greatest eclipse). Click here for a more detailed chart.

Totality – featuring the moon totality inside the Earth’s dark umbral shadow – will last a bit more one and one-fourth hours. Additionally, there will be a partial umbral eclipse roughly one hour before and after totality, with the entire umbral eclipse lasting better than 3 and 1/3 hours. The penumbral eclipse coming before and after the partial umbral eclipse will be very faint and perhaps not even be noticeable to a number of sky watchers. The total lunar eclipse will be visible from western North America, Asia, the Pacific, Australia and New Zealand. At North American time zones, that means the greatest eclipse happens before sunrise on January 31 – the morning of January 31, not the evening. From the world’s Eastern Hemisphere – Asia, Indonesia, New Zealand and Australia – the greatest eclipse takes place after sunset January 31.

Partial umbral eclipse begins: 11:48 Universal Time (UT)
Total eclipse begins: 12:52 UT
Greatest eclipse: 13:30 UT
Total eclipse ends: 14:08 UT
Partial umbral eclipse ends: 15:11 UT

How do I translate Universal Time to my time?

Eclipse times for North American time zones:

Eastern Standard Time (January 31, 2018)
Partial umbral eclipse begins: 6:48 a.m. EST
Moon sets before start of total eclipse

Central Standard Time (January 31, 2018)
Partial umbral eclipse begins: 5:48 a.m. CST
Total eclipse begins: 6:52 a.m. CDT
Moon may set before totality ends

Mountain Standard Time (January 31, 2018)
Partial umbral eclipse begins: 4:48 a.m. MST
Total eclipse begins: 5:52 a.m. MST
Greatest eclipse: 6:30 a.m. MST
Total eclipse ends: 7:08 a.m. MST
Moon sets before end of partial umbral eclipse

Pacific Standard Time (January 31, 2018)
Partial umbral eclipse begins: 3:48 a.m. PST
Total eclipse begins: 4:52 a.m. PST
Greatest eclipse: 5:30 a.m. PST
Total eclipse ends: 6:08 a.m. PST
Partial umbral eclipse ends: 7:11 a.m. PST
Moon may set before end of partial umbral eclipse

Alaskan Standard Time (January 31, 2018)
Partial umbral eclipse begins: 2:48 a.m. AKST
Total eclipse begins: 3:52 a.m. AKST
Greatest eclipse: 4:30 a.m. AKST
Total eclipse ends: 5:08 a.m. AKST
Partial umbral eclipse ends: 6:11 a.m. AKST

Hawaii-Aleutian Standard Time (January 31, 2018)
Partial umbral eclipse begins: 1:48 a.m. HAST
Total eclipse begins: 2:52 a.m. HAST
Greatest eclipse: 3:30 a.m. HAST
Total eclipse ends: 4:08 a.m. HAST
Partial umbral eclipse ends: 5:11 a.m. HAST

Eclipse calculators provide eclipse times for your sky.

Remember … you have to be on the night side of Earth while the lunar eclipse is taking place to witness this great natural phenomenon. Of course, people around the globe want to know whether the eclipse is visible from their part of the world and at what time. To find out the local time of the greatest eclipse in your sky, click on this eclipse calculator and put in the name of a city near you. No time conversion is necessary for this eclipse calculator or the one below because the eclipse times are given in local time.

Eclipse computer via the US Naval Observatory

Animation of the 2018 January 31 total lunar eclipse. The moon travels eastward through the Earth’s penumbra (light outside shadow) and umbra (dark inner shadow) shadow. The yellow line depicts the ecliptic – Earth’s orbital plane. Although the moon, at least in part, spends a little over 3 and 1/3 hours within the umbra, it is only totally submerged in the umbra (dark shadow) for about one and 1/4 hours.

In any umbral lunar eclipse, the moon always passes through Earth’s very light penumbral shadow before and after its journey through the dark umbral shadow.

Who will see a partial lunar eclipse? A partial lunar eclipse precedes the total eclipse by a little over one hour, and follows totality for a little over one hour.

So, from start to finish, the moon takes 3 hours and 23 minutes to totally cross Earth’s dark umbral shadow. Eastern North America can see beginning stages of the partial umbral eclipse low in the west before sunrise January 31, whereas portions of the Middle East and far-eastern Europe can view the ending stages of the partial umbral eclipse low in the east after sunset January 31. South America, most of Europe and Africa won’t be able see this eclipse. See worldwide map below.

Incidentally, a very light penumbral eclipse comes before and after the dark (umbral) stage of the lunar eclipse. But this sort of eclipse is so faint that many people won’t even notice it. The penumbral eclipse would be more fun to watch from the moon, where it would be seen as a partial eclipse of the sun.

Worldwide map of the 2018 January 31 total lunar eclipse

View larger. Need help with the above map, courtesy of EclipseWise.com? Everyplace in white sees the whole eclipse from start to finish, whereas everyplace in black misses out entirely. Let EclipseWise.com by the eclipse master Fred Espenak walk you through the Key to Lunar Eclipse Figures. See less complicated map below.

Day and night sides of Earth at greatest total eclipse

Day and night sides of Earth at greatest eclipse (13:30 UT). The shadow line at left, running through North America, depicts sunrise (moonset). The shadow line at right, running through far-eastern Europe and far-western Asia depicts sunset (moonrise). Image credit: Earth View

What causes a lunar eclipse? A lunar eclipse can only happen at full moon. Only then is it possible for the moon to be directly opposite the sun in our sky, and to pass into the Earth’s dark umbral shadow. Most of the time, however, the full moon eludes the Earth’s shadow by swinging to the north of it, or south of it. For instance, the last full moon on January 2, 2018, swung south of the Earth’s shadow. The next full moon – on March 2, 2018 – will swing north of the Earth’s shadow.

The moon’s orbital plane around Earth is actually inclined at 5o to the ecliptic – Earth’s orbital plane around the sun. However, the moon’s orbit intersects the ecliptic at two points called nodes. It’s an ascending node where it crosses the Earth’s orbital plane going from south to north, and a descending node where it crosses the Earth’s orbital plane, going from north to south.

In short, a lunar eclipse happens when the full moon closely coincides with one of its nodes, and a solar eclipse happens when a new moon does likewise. It’s not a perfect alignment this time around, with the moon turning full about 5 hours before the moon crosses its ascending node. But that’s close enough for this full moon to stage a total lunar eclipse that lasts a touch more than one and 1/4 hours.

The yellow circle shows the sun's apparent yearly path (the ecliptic) in front of the constellations of the Zodiac. The gray circle displays the monthly path of the moon in front of the zodiacal constellations. If a new moon or full moon aligns closely with one of the moon's nodes, then an eclipse is in the works.

The yellow circle shows the sun’s apparent yearly path (the ecliptic) in front of the constellations of the Zodiac. The gray circle displays the monthly path of the moon in front of the zodiacal constellations. If a new moon or full moon aligns closely with one of the moon’s nodes, then an eclipse is in the works.

Bottom line: The super Blue Moon on January 31, 2018, passes right through the Earth’s umbral (dark) shadow, to present a total eclipse of the moon. Details of the eclipse, and eclipse times, here.

Need more details? Visit Fred Espenak’s page

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Time lapse of October 8, 2014 lunar eclipse as reflected in a pond in central Illinois, by Greg Lepper.

Time lapse of October 8, 2014 lunar eclipse as reflected in a pond in central Illinois, by Greg Lepper.

Bruce McClure

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