This event won’t be visible in the U.S. again until 2035.
This sequence of images shows the Moon occulting Mars on Sept. 6, 2020, from Brazil. Credit: Ricardo José Vaz Tolentino
On Jan. 13, the Full Moon will pass in front of Mars during an event astronomers call an occultation. And pretty much anyone in the U.S. with binoculars and a clear sky that night will be able to see it.
Every Full Moon rises at sunset because it lies in the opposite direction of the Sun from our perspective. So, on the 13th, the Moon and Mars will be visible early in the evening and throughout the night. Both objects will be within the boundaries of the constellation Gemini the Twins. And although the Red Planet will be bright — nearly equaling the brilliance of the night sky’s brightest star — the Moon’s overwhelming light output will make this an event only visible through binoculars or telescopes.
When will Mars disappear?
Let’s take a look at a few locations and the times when the Moon begins to cover the Red Planet. From New York City the occultation starts at 9:21 p.m. EST. In Kansas City, it begins at 8:00 p.m. CST. In Denver, start time is 6:57 p.m. MST, and in Los Angeles, it begins at 5:51 PST, which means that observers in West Coast cities like L.A. will have to view the start of the event during twilight. You’ll find a huge listing of the disappearance and reappearance times of Mars on the website of the International Occultation Timing Association (IOTA). Head to this page: http://www.lunar-occultations.com/iota/planets/0114mars.htm.
Note that IOTA’s page shows the occultation occurring on Jan. 14. That’s because the organization uses Universal Time (essentially the time in Greenwich, England) as its basis for calculations. In the U.S., however, the event happens on the night of the 13th.
When is the next occultation of Mars?
Although planetary occultations aren’t rare, to see many of them you’d have to travel to some fairly exotic places. Staying in one location means the next one might not happen for a number of years. And, indeed, if you want to view the next occultation of Mars by the Moon from the U.S., you’ll have to wait until Nov. 11, 2035.
Don’t wait that long. If your sky is clear on the 13th, go out and see some sublime celestial geometry as the Moon blocks our view of Mars for a small amount of time. Good luck!
