The first of the year lunar eclipse on Tuesday, March 3 offers a rare chance to see a strange celestial sight traditionally thought impossible: the rising sun and the eclipsed moon in the sky at the same time.
Views of the total phase of this eclipse favor locations near and around the Pacific Rim. For North America, locations within the Eastern Time Zone will see the moon set under dawn’s early light during the total phase; locations further west will be able to catch the moon emerging from Earth’s shadow as it sets, while for locations out in the far west the eclipse will be visible from start to finish. Hawaiians will see the moon almost overhead as totality takes place in the hours after midnight. Meanwhile, during local evening hours, central Asia and western Australia will see the moon rise as it emerges from Earth’s dark shadow. Eastern Australia, Papua New Guinea, as well as large parts of Japan and eastern Siberia, will see everything in convenient evening hours.
You can stay up to date with everything lunar eclipse this spring lunar eclipse live updates blog.
To see the impossible
But wait! How is this possible? When we have a lunar eclipse, the sun, Earth and the moon is in one geometric straight line in space, with the earth in the middle. So if the sun is above the horizon, the moon must be below the horizon and completely out of sight (or vice versa).
And indeed, during a lunar eclipse, the Sun and Moon are exactly 180 degrees apart in the sky; therefore, in a perfect alignment like this (a “syzygy”), such an observation would seem impossible.
But it is atmospheric refraction which makes a selenelion possible.
Atmospheric refraction causes astronomical objects to appear higher in the sky than they actually are.
For example, when you see the sun sitting on the horizon, it is not there. It actually sits just below the edge of the horizon, but our atmosphere acts like a lens and bends the Sun’s image just above the horizon so we can see it.
This effect also extends the amount of daylight for several minutes or more each day; we end up seeing the sun a few minutes in the morning before it has actually risen and a few extra minutes in the evening after it has actually already set.
The same applies to the moon as well.
Because of this atmospheric trick, for many locales there will be an unusual chance to observe a Selenelion firsthand with this impending shadowy event. There will be a short window of about 1 to 3 minutes (depending on your location) when you may be able to see the sun rise in the east-southeast and the eclipse. full moon setting in the west-northwest.
Read more: Where to see the total lunar eclipse in the early hours of March 3
Visibility areas
For locations west of the Continental Divide, this effect may unfortunately not be visible. For most places in the Mountain and Pacific Time Zones, the Moon will have moved completely clear of Earth’s dark umbral shadow before setting. Those in the Mountain Time Zone will see the moon set while it is still within the Earth’s penumbra.
This shadow is so faint that at least 50-70% of the Moon must be immersed in it before you have a chance to detect it visually, either with the naked eye or using an optical aid. For locations in the southern and central Rockies, such as Santa Fe, New Mexico, or Denver, Colorado, the lower right portion of the moon will appear somewhat darker or “mottled” as it begins to disappear beyond the western horizon.
However, further north, from Jackson, Wyoming and Butte, Montana, the moon will look completely normal as it sets.
Over most places in the Central Time Zone, total phase will have passed and the Moon will emerge from Earth’s umbra. Depending on where you are, the moon may look like a half moon, a half moon, or just a “chunk” taken out of the lower right limb.
For most places in the Eastern Time Zone, the Moon will be set fully immersed in the Earth’s shadow, while for the Atlantic Canada provinces (Nova Scotia, New Brunswick, Prince Edward Island and Newfoundland) only the partial opening stages will be visible with the Moon’s waning before totality occurs.
|
Place |
Time zone |
Sunrise |
Moon waning |
Eclipse |
|---|---|---|---|---|
|
Halifax |
AST |
06:48 |
06:49 |
81% |
|
Boston |
EST |
06:16 |
06:17 |
Total eclipse |
|
New York |
EST |
06:26 |
06:28 |
Total eclipse |
|
Montreal |
EST |
06:29 |
06:30 |
Total eclipse |
|
Washington, DC |
EST |
06:38 |
06:39 |
Total eclipse |
|
Atlanta |
EST |
07:03 |
07:05 |
97% |
|
Chicago |
CST |
06:22 |
06:24 |
72%* |
|
New Orleans |
CST |
06:24 |
06:26 |
69%* |
|
Kansas City |
CST |
06:48 |
06:51 |
35%* |
|
Austin |
CST |
06:55 |
06:58 |
26%* |
|
Winnipeg |
CST |
07:07 |
07:10 |
9%* |
This table shows the local times of moonrise and moonset, along with the percentage of the moon’s diameter that is within the dark umbral shadow at the time of moonset, for 11 selected cities. A star
indicates that totality has already occurred and that the moon is emerging from the umbral shadow. Note that places farther west have the moon and sun together in the sky for a noticeably longer interval. That’s because after mid-eclipse, the moon’s orbital motion has taken it a little more to the east and thus higher in the sky, so it remains visible a little longer.
Important facts to consider
To observe the Selene Lion, make sure that both your eastern and western horizons are clear of tall obstacles that could block your view of the setting moon or the rising sun.
Also note that depending on the clarity of your sky, you may lose sight of the moon about 10 or 15 minutes before sunrise, thanks to the bright morning twilight and the moon descending into a horizontal haze (atmospheric “schmutz”).
Remember that this only applies to the non-eclipsed part of the moon. In fact, if the moon is totally eclipsed at waning moon, you’ll likely need to scan the western horizon as dusk deepens to spot the darkened moon, which might look like a dimly and eerily lit softball.






