521.

The cluster IC 4665 is well placed The open star cluster IC 4665 (mag 4.2) in Ophiuchus culminates at around midnight local time. Sun, 18 Jun 2023 (394 days ago) in Ophiuchus

522.

The Ptolemy cluster is well placed The Ptolemy Cluster (M7, NGC 6475; mag 3.3) in Scorpius culminates at around midnight local time. Tue, 20 Jun 2023 (392 days ago) in Scorpius

523.

June solstice 21 June will be the longest day of 2023 in the northern hemisphere. Wed, 21 Jun 2023 at 10:54 EDT (391 days ago) in Taurus

524.

Conjunction of the Moon and Venus The Moon and Venus share the same right ascension, at a separation of 3°41'. Wed, 21 Jun 2023 at 20:48 EDT (391 days ago) in Cancer

525.

Close approach of the Moon and Venus The Moon and Venus pass close to each other. Wed, 21 Jun 2023 at 23:13 EDT (391 days ago) in Cancer

526.

Conjunction of the Moon and Mars The Moon and Mars share the same right ascension, at a separation of 3°47'. Thu, 22 Jun 2023 at 06:10 EDT (390 days ago) in Leo

527.

Close approach of the Moon and Mars The Moon and Mars pass close to each other. Thu, 22 Jun 2023 at 08:54 EDT (390 days ago) in Leo

528.

The Moon at apogee The Moon recedes to its orbit's furthest point from the Earth, making it appear fractionally smaller than at other times of the month. Thu, 22 Jun 2023 at 14:30 EDT (390 days ago) in Leo

529.

The Lagoon Nebula is well placed The Lagoon Nebula (M8; mag 5.8) in Sagittarius culminates at around midnight local time. Fri, 23 Jun 2023 (389 days ago) in Sagittarius

530.

NGC 6541 is well placed The globular cluster NGC 6541 (mag 6.6) in Corona Australis culminates at around midnight local time. Sat, 24 Jun 2023 (388 days ago) in Corona Australis

531.

Moon at First Quarter The Moon reaches first quarter phase – appearing high in the sky at sunset and setting in the west at around midnight. Mon, 26 Jun 2023 at 03:50 EDT (386 days ago) in Virgo

532.

Mercury at perihelion Mercury passes its orbit's closest point to the Sun. Tue, 27 Jun 2023 at 15:17 EDT (385 days ago) in Gemini

533.

June Bootid meteor shower 2023 The June Bootid meteor shower reaches its peak. Tue, 27 Jun 2023 (385 days ago) in Bootes

534.

The cluster NGC 6633 is well placed The open star cluster NGC 6633 (mag 4.6) in Ophiuchus culminates at around midnight local time. Thu, 29 Jun 2023 (383 days ago) in Ophiuchus

535.

Neptune enters retrograde motion Neptune reverses its direction of motion across the sky. Fri, 30 Jun 2023 at 15:28 EDT (382 days ago) in Pisces

536.

Lunar occultation of Delta Scorpii The Moon will pass in front of Delta Scorpii (Dschubba), creating a lunar occultation visible from countries and territories including Antarctica, French Southern Territories, South Georgia and the South Sandwich Islands and Heard Island and McDonald Islands amongst others. Fri, 30 Jun 2023 at 15:54 EDT (382 days ago) in Scorpius

537.

Mercury at superior solar conjunction Mercury passes around the far side of the Sun. Sat, 01 Jul 2023 at 01:12 EDT (381 days ago) in Gemini

538.

Close approach of Venus and Mars Venus and Mars pass within 3°33' of each other. Sat, 01 Jul 2023 at 03:09 EDT (381 days ago) in Leo

539.

Comet C/2023 E1 (ATLAS) passes perihelion Comet C/2023 E1 (ATLAS) makes its closest approach to the Sun. Sat, 01 Jul 2023 (381 days ago)

540.

Messier 22 is well placed The globular cluster M22 (mag 5.2) in Sagittarius, near the Galactic centre, culminates at around midnight local time. Sat, 01 Jul 2023 (381 days ago) in Sagittarius