Brilliant Mars will vanish tonight. It’s not going anywhere — it’s just blocked out by something else.

Mars is at its biggest and boldest this month. It’s at opposition — it lines up opposite the Sun in our sky. It rises at sunset, is in view all night, and is closest to Earth for the year. As a result, it shines at its brightest — the fourth-brightest object in the night sky.

Tonight, though, around the moment of opposition, it will vanish for most of us in the United States. Another object at opposition — the full Moon — will occult the Red Planet, blocking it from view.

It’s just a coincidence that Mars and the Moon reach opposition at almost the same time. The Moon circles past Mars roughly once a month. As with lunar and solar eclipses, though, the conditions are usually a bit off for an occultation. The orbits of Mars and the Moon are tilted at different angles, so they don’t always overlap. The geometry has to be just right for the Moon to pass in front of Mars.

This occultation will be visible from all of the United States except the southeast, Hawaii, and most of Alaska. The timing depends on your location.

At most, the Moon will cover Mars for a little more than an hour. Mars looks like a bright star, although the moonlight will wash it out a bit and bleach its normal orange color — draining a bit of drama from the Red Planet’s best showing of the year.

We’ll have more about Mars tomorrow.
 

Script by Damond Benningfield

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