May 2026

Southern hemisphere sky watchers get a good view of three naked eye planets lined up in the morning as May begins. Those with binoculars or telescopes can also see a fourth. In order from top to bottom are Neptune, Saturn, Mars, and Mercury. They’re lined up sort of along one of the Pisces fish. Mercury is actually between the fish and Saturn is within the boundaries of Cetus.

Mercury quickly exits the morning sky. The rest of this planet group continues moving at different paces directly, or eastward, among the stars. By mid-month, Mars has moved into the area where Mercury was at the start. The moon is next to Neptune on the 13^th. Then it passes Saturn and Mars over the next two days. After the 17^th, it’s easy to see Mars and Saturn looking like they’re accompanying the fish, the red planet on one side of the constellation and the ringed planet on the other. Actually, from May 19 through June 3, neither planet is within the International Astronomical Union’s boundaries for Pisces. Mars has moved into Aries and Saturn’s still on the way from Cetus. But we don’t see the boundaries.

In the evening sky, Uranus is setting sooner after sunset. It’s not too hard for most observers to spot with magnification early in the month. It’s still near the Pleiades. Venus is above it, starting May closer to the Hyades. Jupiter stars May close to Wasat in Gemini. Venus moves up, passing Elnath on the boundary of Taurus and Auriga around the 12^th. On the 18^th, the planet will be at the feet of Castor in Gemini with the moon nearby. By then, Jupiter is heading out of Gemini under Pollux’s arm. The moon passes by Jupiter on the 20^th.

After that, observers at low northern latitudes can try to spot Mercury entering the evening sky after superior conjunction on the 14^th. The messenger planet gets much easier to see by the end of the month as it also races toward Gemini, passing Elnath on the 27^th when Venus is closest to Mebsuta at Castor’s hips. As May ends, Jupiter is clearly on its way out of the constellation, Venus is right in the middle of it, and Mercury is about to enter at Castor’s feet. Keep watching for these three planets to line up nicely in June and even get a visit from the moon.

Venus is at perihelion on the 15^th and Mercury is on the 18^th. Their respective distances from the sun will be 0.72 and 0.31 astronomical units, or earth-sun distances.

The month starts with a full moon. That’s on the 1^st. Last quarter is on the 9^th. New moon is on the 16^th. First quarter is on the 23^rd. And a second full moon for May happens on the 31^st.

Southern lunistice is on the 5^th at 28.1°. The moon goes north over the equator on the 12^th. Northern lunistice is on the 18^th at 28.1°. And the moon goes south on the 25^th.

The moon’s at apogee on the 4^th. The center-to-center distance is 405,900 km.. Perigee occurs on the 17^th at 358,100 km.

The moon occults Antares twice this month. On the 4^th, or the evening of the 3^rd in South America, the moon hides the orange star for observers from Chile and Argentina, across the far southern Atlantic Ocean, almost to the tip of southern Africa. On the 31^st, the star is occulted for observers in eastern Australia and New Zealand, across the far southern Pacific, and to southern South America. Chile and Argentina get a second occultation and when the moon is full! Because the visibility area crosses the International Date Line, it will begin as an evening event and end on the morning of the same date on different continents.

On the 23^rd, observers on islands and boats in the central and southern Pacific Ocean can see the moon occult Regulus.