The first total lunar eclipse since 2022 will turn the full moon an eerie shade of red on the night of March 13-14 — but your chances of seeing it with your own eyes will depend on where you are.
North Americans should have great seats for the eclipse this time around. The key phases of the show, from the time the moon begins to enter the darkest part of Earth’s shadow to the time it leaves, should be visible to the entire continent.
But add some emphasis to the word “should.” In order to see the darkened moon with your own eyes, the skies have to be clear.
First, a little background: Lunar eclipses occur when the sun, Earth and moon line up just right for our planet’s shadow to block the direct sunlight hitting the moon’s surface during its full phase. That doesn’t happen every time the moon swings around behind Earth — it all depends on the precise orbit-by-orbit alignment. That’s why it’s been two and a half years since the last round of lunar totality.
Even during the eclipse’s total phase, the moon doesn’t go completely dark. Earth’s atmosphere refracts the sun’s rays, so some of those rays are bent enough to hit the moon’s surface and get reflected back to us. Reddish wavelengths are refracted the most, while bluish wavelengths are scattered as they pass through the atmosphere. That’s why the moon takes on a reddish glow — it’s similar to how the skies turn red on Earth at sunrise and sunset.
Prime time for the March 13-14 eclipse starts at 10:09 p.m. PT, when the leading edge of the moon’s disk crosses into the darkest part of Earth’s shadow, also known as the umbra. Totality begins when the moon is fully shadowed at 11:26 p.m. PT, and lasts until 12:32 a.m. PT March 14. The show is basically over when the moon’s trailing edge leaves the umbra at 1:48 a.m. PT. (The hard-to-discern penumbral phase of the eclipse continues until 3 a.m. PT.)
This chart shows phases of the March 13-14 lunar eclipse, with times listed for the Pacific time zone. (Credit: Sky & Telescope)
What about the weather? You can use the National Weather Service’s graphical forecast chart to find out what the cloud cover is expected to be in your area. Just zero in on your area of the country, select “Sky Cover” from the drop-down menu just above the map and to the left, and then click on the slider bar on the right to get to the proper time on the night of March 13-14. The map will show how much of the sky is expected to be covered by clouds in percentage terms.
Clear Dark Sky is another useful online tool for checking the forecast. Search for your area and check the chart to see what a computer model optimized for astronomical viewing thinks of the prospects for clear skies. A deep-blue square is good. Gray or white, not so much.
For what it’s worth, the outlook for clear skies in the Seattle area is iffy, but worth taking a chance. The outlook improves east of the Cascades.
What if you’re totally clouded out? Even if you’re on the other side of the world, you can still get a look at this week’s “Blood Moon” online in real time. Check out Space.com’s roundup of lunar eclipse webcasts.
The next total lunar eclipse will take place on Sept. 7-8, but that one will favor observers in east Africa, Asia and Australia. North and South America will miss out. Most folks in the United States will get their next encounter with lunar totality almost a year from now.
