Astronomical events in May will be spectacular. You can observe two full Moons and the Eta Aquarid meteor shower in the early morning of May 6. There will also be several close approaches and conjunctions that are easy to follow, using the Moon as your guide.
Times are given for Montréal in Eastern Daylight Time (EDT).
Sky events not to be missed
- May 6: Eta Aquarids peak – best viewing between 2:29 and 4:59 a.m., just before dawn.
- May 18: the Moon near Venus – look for earthshine on the Moon.
- May 19: the Moon near Jupiter – a very photogenic evening pair.
- May 29: Venus reaches its maximum altitude in the evening sky.
- May 31: Full Moon at dawn (a “blue Moon”), followed by a Venus–Jupiter close approach in the early evening.
Celestial events, day by day
May 1: Full Moon (100%) at 1:23 p.m. EDT.
May 1: Conjunction – Close approach of Saturn and Neptune. Just before sunrise, Saturn will rise in the east, with Neptune just to its right, visible with binoculars or a small telescope.
May 1: Conjunction – Close approach of Venus, Uranus and M45 (the Pleiades). The trio will be visible just after sunset, looking toward the west. Venus will shine brightly, with M45 (the open star cluster) to its right, while Uranus can be seen slightly to the left, below M45, with binoculars. These observations will also be possible in the following days.
May 2: Conjunction – Close approach of Uranus and M45. The Pleiades open star cluster and Uranus will be at their closest in the sky just after sunset.
May 4: Moon at apogee (91%) at 6:20 p.m. EDT—its farthest point from Earth (404,816 km).
May 5: Conjunction – Close approach of the Moon (88%) and M7 (the Ptolemy Cluster). Located to the left of the Moon, the open star cluster M7 will follow the Moon throughout the night until sunrise. Visible from 4 a.m. EDT.
Night of May 5 to 6: Eta Aquarid meteor shower
Active from April 19 to May 28, the shower reaches peak activity around May 6. During this period, meteors can be observed whenever the radiant, located in the constellation Aquarius, is above the horizon.
The number of visible meteors increases as the radiant rises higher in the sky but remains relatively low (3 to 4 per hour in Montréal). From Montréal, the shower will not be visible before about 2:30 a.m. EDT each night, when the radiant rises in the east. It remains visible until dawn, around 5 a.m. EDT.
Peak activity is expected around 5 a.m. EDT on May 6. The best observations will therefore occur before dawn that day, as well as after the radiant rises the following night.
May 9: Last Quarter Moon (50%) at 5:10 p.m. EDT.
May 13: Conjunction – Close approach of the Moon (16%), Saturn and Uranus. Just before sunrise, a thin crescent Moon will appear with Saturn below it to the left, looking east. Neptune will be visible to the right of the Moon with binoculars or a small telescope. Mars will also make a faint appearance, very low on the horizon.
May 14: Mercury at superior solar conjunction.
In astronomy, a superior solar conjunction occurs when a planet passes directly behind the Sun as seen from Earth.
Mercury will be invisible on May 14, lost in the Sun’s glare. The planet will pass very close to the Sun in the sky as its orbit carries it to the opposite side of the Solar System from Earth. This phenomenon occurs once per synodic cycle (about every 116 days) and marks the end of Mercury’s morning apparition, as it transitions to become an evening object in the following weeks.
May 14: Conjunction – Close approach of the Moon (8%) and Mars. A thin crescent Moon will appear to the right of Mars, which rises just before the Sun. Difficult to observe due to its very low position on the eastern horizon, Mars will become increasingly visible in the coming weeks, well before sunrise. Saturn will be to the right of the Moon.
May 16: New Moon (0%) at 4 p.m. EDT.
May 17: Moon at perigee (1%) at 9:37 a.m. EDT—its closest point to Earth (358,082 km).
May 18: Conjunction – Close approach of the Moon (7%) and Venus. Look toward the east just after sunset. A beautiful conjunction will appear between a thin crescent Moon and Venus to its left, visible in the west from sunset until moonset. Jupiter follows farther to the left. Take this opportunity to observe earthshine—the part of the Moon illuminated by sunlight reflected from Earth.
May 19: Conjunction – Close approach of the Moon (15%) and Jupiter. Continuing along its path, the Moon then meets Jupiter over two nights. Jupiter will be to the left of the Moon, while Venus will be lower on the horizon to the right. Visible in the west from sunset until midnight.
May 21: Conjunction – Close approach of the Moon (35%) and M44 (the Beehive Cluster). The Moon continues its journey and visits the open star cluster M44. It will appear to the right of the Moon toward the west. Visible until 1 a.m. EDT on the morning of May 22.
May 22: Uranus at superior solar conjunction. This celestial event means that Uranus passes behind the Sun as seen from Earth. The planet will then be at its maximum distance from us (about 20.48 astronomical units) and completely invisible, lost in the Sun’s glare for several weeks.
May 23: First Quarter Moon (50%) at 7:10 a.m. EDT.
May 29: Venus at its maximum altitude in the evening sky. As seen from Montréal, Venus will reach its highest point of the year during its evening apparition. It will shine brightly at magnitude −4.3. From Montréal, this apparition will not be among the most striking, reaching a maximum altitude of about 25° above the horizon at sunset.
May 30: Conjunction – Close approach of Jupiter and Venus. It will be visible in the west from sunset to 11 p.m. EDT. Jupiter will be to the left of Venus, both shining brightly. This must-see event will continue into June.
May 31: Full Moon (100%) at 1:23 p.m. EDT—this second full Moon of May is known as a “blue Moon.”
May 30 and 31 : The Planétarium invites you to AstroFest 2026! The annual gathering for skywatching enthusiasts will explore the theme “Living in space.” The 6th edition of this free event will take place in a festive atmosphere.
