The moon’s at last quarter on the first day of May. It’ll rise around local midnight in Capricornus. A thinning crescent will be near Saturn in the morning sky on the 4th. Then it’s by Mars on the 5th, the same day the moon crosses the equator going north and is at perigee at 363,100 kilometers away. The moon will occult each planet. The Saturn occultation will be visible mainly from Antarctica and the nearby Southern Ocean. The Mars event will be visible over part of the Indian Ocean.
A very thin crescent, old moon will be near Mercury on the morning of the 6th. The southern hemisphere gets the best view. In the northern hemisphere, you might not see the planet. But if you can spot the thin crescent, look for Mercury. You may need binoculars to pick it out of the coming sunrise’s glow. Mercury itself will be a thick crescent if you can view it in a telescope.
If you want another challenge, look for the moon and Venus on the morning of the 7th. The best (but not really good) view is from around 20° south. You might be able to spot Venus rising shortly before the sun with the moon just a little up and to the left. New moon will be the next day.
If those two challenges aren’t enough, here’s another. As the young moon emerges into the evening sky, it passes Jupiter on the way out of it. There’s probably nowhere on Earth where you can see them easily. Around 10° north may be the best place to be, if it’s possible to see them there. Watch the moon pass near Aldebaran on the 9th. Then it’s off to Gemini for northern lunistice at 28.5° on the 11th and a pass near Pollux on the 12th.
See a first quarter moon in Leo close to Regulus on the 15th. Lunar apogee is on the 21st at 404,700 kilometers when the moon is heading out of Leo and into Virgo. It cross the equator southward on the 18th. A waxing gibbous moon is near Spica on the 20th. Full moon is on the 23rd and then Antares will be occulted on the 24th Universal Time. That event is visible from the southeastern United States, the Caribbean, northern South America, and much of the Atlantic Ocean.
The moon reaches 28.4° south for southern lunistice on the 25th. It will be near the asteroid Ceres on the 27th. Another last quarter is on the 30th. And on the 31st, the moon passes in front of Saturn for viewers in far southern South America.
Planet watching is somewhat limited this month because of so many of them appearing so close to the sun. Uranus is in conjunction on the 13th. Jupiter follows on the 18th.
Mercury is at greatest elongation in the morning sky, 26.4° from the sun, on the 9th. The best views are from low and middle southern latitudes. For the rest of the month, you can see Mars dropping lower along the sky, not as fast as Mercury does, and Saturn above it dropping even slower. Some southern hemisphere sky watchers may be able to spot Jupiter emerging into the morning sky in the last days of May.
Mars is at perihelion on the 8th at 1.38 astronomical units from the sun.
The Eta Aquariids meteor shower peak is expected on the 5th. Halley’s Comet provides the dust trails that produce this shower. The comet just went through aphelion late last year, so it is still nearly as far as it gets from us. You could see up to 50 meteors per hour. And with the moon approaching new, there’ll be little moonlight to interfere.
Another shower, the Eta Lyrids, peaks on the 8th. This is a minor shower. You may see just three per hour.