Here are some details on the Moon’s phases, close approaches of planets and other astronomical events to look for in April.
April 1: Full Moon (100%) at 10:11 p.m. EDT.
April 3: Mercury at its greatest western elongation (mag −0.2, its greatest angular separation from the Sun) during its morning apparition. From Montréal, this apparition will be very difficult to observe. Look for it just before sunrise in the east.
April 4 and 6: Comet C/2026 A1 (MAPS) will reach perihelion (its closest point to the Sun) on April 4 and perigee (its closest point to Earth) on April 6. This event is highly uncertain (but worth watching around sunset the following week if the comet survives perihelion).
April 7: Moon at apogee (68%) at 4:25 a.m. EDT—its farthest point from Earth (404,945 km).
April 10: Last Quarter Moon (50%) at 12:52 a.m. EDT.
From April 13 to 20, four planets are visible: Mars (mag +1.2), Mercury (mag 0), Saturn (mag +1) and Neptune (mag +7.8) form a group that the Moon passes by each day. You will need a small telescope to observe Neptune, which is too faint to be seen with the naked eye. The four planets are visible in the east before sunrise but remain difficult to see as they are low on the horizon.
April 13: Conjunction – Close approach of Mars (mag +1.2) and Neptune (mag +7.8). Neptune lies at the lower right of Mars. You can spot it, once you’ve located Mars, using binoculars or a small telescope before sunrise, looking toward the east.
April 15: Conjunction – Close approach of the Moon (6%), Mercury (mag 0) and Mars (mag +1.2). Mercury lies south of a thin crescent Moon and will be visible in the east before sunrise. Mars (mag +1.2) will be to the right of Mercury, while Saturn (mag +1) will be slightly to the lower left of Mars. Neptune (mag 7.8) will be between Mars and Mercury. All are visible in the east before sunrise.
April 16: Conjunction – Close approach of the Moon (1.5%) and Saturn (mag +1). The very thin crescent Moon will be to the left of Saturn, with Mars and then Mercury following Saturn. Visible early before sunrise. Neptune (mag 7.8, binoculars required) will be closest to Mercury that morning.
April 17: New Moon (0%) at 7:51 a.m. EDT.
April 19: Moon at perigee (9%) at 2:55 a.m. EDT—its closest point to Earth (361,646 km).
April 19: Conjunction – Close approach of Mercury (mag 0) and Mars (mag +1.2). In the early morning before sunrise, Mercury lies to the lower left of Mars. Saturn will also be present, slightly above Mercury.
April 19: Conjunction – Close approach of the Moon (9%) and Venus (mag −3.9). Uranus (mag +5.8) will lie between the Moon and Venus, along with the open star cluster M45 (the Pleiades), slightly to the lower right of the Moon. You will need binoculars to see Uranus. The whole scene unfolds after sunset.
April 20: Conjunction – Close approach of Mercury (mag 0) and Saturn (mag +1) (30′); and Saturn (mag +1) and Mars (mag +1.2).
Night of April 21 to 22: Lyrid meteor shower (active from April 15–16 to April 29–30). Peak (theoretical): Wednesday, April 22 at 3:15 p.m. EDT (7:15 p.m. Coordinated Universal Time [UTC]). Best viewing in the Montréal area: late in the night of April 22 (before dawn), under a moonless sky (crescent Moon sets before 2 a.m.). Typical zenithal hourly rate (ZHR): 10 to 18 meteors per hour (under dark skies).
April 22: Conjunction – Close approach of the Moon and Jupiter (mag −2.1). Visible in the early evening, high in the southwest, then descending until it sets around 1:30 a.m. on April 23.
April 23: First Quarter Moon (50%) at 10:31 p.m. EDT.
April 24: Conjunction – Close approach of Venus (mag −3.9) and Uranus (mag +5.8). Just after sunset, look for the very bright planet (Venus), then point your binoculars slightly below it to spot Uranus.
April 24: Conjunction – Close approach of the Moon (60%) and M44 (the Beehive). Located to the right of the Moon, the open star cluster M44 will follow the Moon throughout the night until it sets around 3 a.m. on the morning of April 25.
April 25: Join us for Skywatch Gatherings at the Planétarium—a free stargazing event open to all.