The moon is throwing a historic block party today (Sept. 18).
Earth’s nearest neighbor occulted, or covered up, Venus and the bright star Regulus in the sky this morning hours, and can swallow up Mercury and Mars tonight.
The moon hadn’t occulted three planets in a single 24-hour span since March 2008, and it will not do so again until July 2036, according to EarthSky.org.
But do not get too excited skywatchers.
“Overall, this string of planetary occults might become more of the academics than observational interest, because a lot of the world is not well-situated for viewing even one of the four occultations particularly,” EarthSky.org wrote yesterday (Sept. 17).
Indeed, all occasions pretty much go by North European countries and America, favoring the Southeast Asia and Pacific regions generally.
“Even at that, the occults of Regulus, Mars, and Mercury will be hard to see because they occur in a daytime sky extremely,” McClure wrote. “Certainly, you may need a telescope to see anybody of these lunar occultations – that is, if anyone of these takes place in your sky even.”
The moon will block Mars at about 4 p.m. EDT (2000 GMT) today within an occultation visible from elements of SOUTH USA, Central America, Mexico and the Pacific Sea. The Mercury occultation occurs at around 7 p.m. EDT (2300 GMT); it will be noticeable from the mid-Pacific into Southeast parts and Asia of China.
You can view visibility maps for every one of the events here