281.

Conjunction of the Moon and Mars The Moon and Mars share the same right ascension, at a separation of 39'. Sat, 16 Sep 2023 at 15:20 EDT (284 days ago) in Virgo

282.

Comet C/2023 P1 (Nishimura) passes perihelion Comet C/2023 P1 (Nishimura) makes its closest approach to the Sun. Sun, 17 Sep 2023 (283 days ago) in Virgo

283.

The Moon at perihelion The Moon passes its orbit's closest point to the Sun, which happens each month around the time of new moon. Sun, 17 Sep 2023 at 13:19 EDT (283 days ago) in Virgo

284.

Venus at greatest brightness Venus reaches its greatest brightness in the dawn sky. Mon, 18 Sep 2023 at 08:09 EDT (282 days ago) in Cancer

285.

Neptune at opposition Neptune lies in the opposite direction to the Sun in the sky, making it optimally positioned to be observable for much of the night. Tue, 19 Sep 2023 at 07:09 EDT (281 days ago) in Pisces

286.

Lunar occultation of Antares The Moon will pass in front of Antares (Alpha Scorpii), creating a lunar occultation visible from Japan, Russia, Guam and Northern Mariana Islands. Thu, 21 Sep 2023 at 04:47 EDT (279 days ago) in Scorpius

287.

Mercury at greatest elongation west Mercury is bright and well placed in the dawn sky. Fri, 22 Sep 2023 at 07:27 EDT (278 days ago) in Leo

288.

Mercury at dichotomy Mercury reaches half phase in the dawn sky. Fri, 22 Sep 2023 at 15:26 EDT (278 days ago) in Leo

289.

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. Fri, 22 Sep 2023 at 15:32 EDT (278 days ago) in Sagittarius

290.

September equinox Day and night have equal length, marking the beginning of autumn in the northern hemisphere and spring in the southern hemisphere. Sat, 23 Sep 2023 at 02:46 EDT (277 days ago) in Virgo

291.

Mercury at highest altitude in morning sky Mercury is bright and well placed in the dawn sky. Sat, 23 Sep 2023 (277 days ago) in Leo

292.

Mercury at perihelion Mercury passes its orbit's closest point to the Sun. Sat, 23 Sep 2023 at 14:06 EDT (277 days ago) in Leo

293.

NGC 55 is well placed NGC 55 (mag 8.2), a barred irregular galaxy in Sculptor culminates at around midnight local time. Mon, 25 Sep 2023 (275 days ago) in Sculptor

294.

Conjunction of the Moon and Saturn The Moon and Saturn share the same right ascension, at a separation of 2°38'. Tue, 26 Sep 2023 at 21:29 EDT (274 days ago) in Aquarius

295.

Close approach of the Moon and Saturn The Moon and Saturn pass close to each other. Tue, 26 Sep 2023 at 23:12 EDT (274 days ago) in Aquarius

296.

The Moon at aphelion The Moon recedes to its orbit's furthest point from the Sun, which happens each month around the time of full moon. Wed, 27 Sep 2023 at 02:44 EDT (273 days ago) in Aquarius

297.

47 Tuc is well placed The second brightest globular cluster in the sky, 47 Tuc (NGC 104; mag 4.0), in Tucana culminates at around midnight local time. Wed, 27 Sep 2023 (273 days ago) in Tucana

298.

Daytime Sextantid meteor shower 2023 The Daytime Sextantid meteor shower reaches its peak. Wed, 27 Sep 2023 (272 days ago) in Sextans

299.

The Moon at perigee The Moon makes its monthly closest approach to the Earth, making it appear fractionally larger than at other times of the month. Wed, 27 Sep 2023 at 20:58 EDT (273 days ago) in Aquarius

300.

Full Moon The Moon reaches full phase and is visible for much of the night. Fri, 29 Sep 2023 at 05:57 EDT (271 days ago) in Pisces