May skygazing: A blue moon, fading comet, and a lot of meteors

It’s spring! All is beautiful and full of life, and apart from that one weird smell, all is well in the great outdoors. Along with flowers and seasonal allergies, this month brings us plenty of opportunities for stargazing, from not one but two full moons to a meteor shower and the year’s first Lāhainā noon.

May 1: Full Flower Moon

The full Flower Moon on May Day? How much more spring-y can spring get? Unsurprisingly, the Flower Moon gets its name from the blooms that burst into life as winter releases its hold on the land. The Farmer’s Almanac attributes the name to several possible North American sources, including the Algonquin peoples of the continent’s northeast and/or the Dakota people of the Midwest. The moon will reach its peak illumination at 1:23 p.m. EDT on May 1.

May 4: One Last Chance to Catch Comet C/2025 R3 (Possibly)

If you missed Comet C/2025 R3 last month, or you just want another chance to look at it before it departs, you might be able to catch a glimpse depending on where you are. In the Northern Hemisphere, the combination of the (almost) full moon and the comet’s proximity to the sun will make it all but impossible to spot before it disappears over the horizon and moves into southern skies.

If you’re in the Southern Hemisphere, you’ll have a little longer to try to take a look. The comet’s brightness will be decreasing, so you’ll need at least a good pair of binoculars, or ideally a small telescope, to see it. As per Starwalk, the comet will trace a line over the course of the month, starting in the constellation Eridanus on May 4, and moving up through Orion toward the Red Rectangle nebula.

If you miss out this time, well, that’s basically it. The comet’s orbital period is notionally around 170,000 years, but the latest models suggest that it ain’t coming back at all, predicting that it will be ejected from our Solar System entirely after this journey around the sun.

May 5: Eta Aquarids Meteor Shower Predicted Peak

The Southern Hemisphere also gets the lion’s share of this month’s only notable meteor shower, the Eta Aquarids. May’s annual meteor shower is predicted to peak on the morning of May 5. But never fear, because the shower is also visible from the Northern Hemisphere, albeit in reduced volumes. Southern skies are predicted to get up to 60 meteors per hour, with the north getting about half that number. As per EarthSky, the best time to look is just before dawn, when the moon is sinking toward the horizon. Look south toward the constellation Aquarius and enjoy the show!

The other notable fact about the Eta Aquarids is their source: Halley’s Comet. The famous space rock last visited in 1985 and makes an appearance in the Bayeux Tapestry, where it features as a harbinger of doom.

May 14: May’s Lāhainā Noon Begins

This month will bring the first of this year’s two Lāhainā noons for those living between the Tropics of Cancer and Capricorn. If you live in the United States, that basically means people in Hawai’i, because the continental U.S. lies entirely north of the Tropic of Cancer. On May 14, the sun at noon will be directly overhead, which means that for a few moments, vertically standing objects—telephone poles, flagpoles, people—will not cast any shadows. For those of us non-tropical types unused to the phenomenon, it’s very strange—and not a little disconcerting—to behold.

Incidentally, if you’ve ever wondered, this is what defines the tropics: the Tropics of Cancer and Capricorn demarcate the boundaries of the region of the earth from which the sun can be seen directly overhead. The more you know!

May 31: Full Blue Micromoon

I’ve been writing this column for a little over a year, and this is my first time writing about… a blue moon! This is the name given to the second full moon in a month, an occasion rare enough to have given rise to the expression “once in a blue moon.” In fairness, it turns out that they’re not that rare. Blue moons happen about once every two-and-a-half years—but still, they’re unusual enough to be exciting.

This month’s blue moon is also a micromoon.It’s smaller than usual because it occurs while the moon is near its furthest distance from the Earth. You can see it reach its peak illumination at 4:45 a.m. EDT on May 31. And just to be clear, it will not in fact be blue.  

Also, if you’re wondering whether we can ever go through a month without a full moon, the answer is yes—but only in February.

Anyway, whatever you choose to gaze upon this month, remember that you’ll get the best experience gazing at the cosmos if you get away from any sources of light pollution, give your eyeballs some time to adjust to the darkness, and review our stargazing tips before setting out into the night.

Until next time! 

 

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