221.

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 (244 days ago) in Virgo

222.

Comet C/2023 P1 (Nishimura) passes perihelion Comet C/2023 P1 (Nishimura) makes its closest approach to the Sun. Sun, 17 Sep 2023 (243 days ago) in Virgo

223.

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 (243 days ago) in Virgo

224.

Venus at greatest brightness Venus reaches its greatest brightness in the dawn sky. Mon, 18 Sep 2023 at 08:09 EDT (242 days ago) in Cancer

225.

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 (241 days ago) in Pisces

226.

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 (239 days ago) in Scorpius

227.

Mercury at greatest elongation west Mercury is bright and well placed in the dawn sky. Fri, 22 Sep 2023 at 07:27 EDT (238 days ago) in Leo

228.

Mercury at dichotomy Mercury reaches half phase in the dawn sky. Fri, 22 Sep 2023 at 15:26 EDT (238 days ago) in Leo

229.

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 (238 days ago) in Sagittarius

230.

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 (237 days ago) in Virgo

231.

Mercury at highest altitude in morning sky Mercury is bright and well placed in the dawn sky. Sat, 23 Sep 2023 (237 days ago) in Leo

232.

Mercury at perihelion Mercury passes its orbit's closest point to the Sun. Sat, 23 Sep 2023 at 14:06 EDT (237 days ago) in Leo

233.

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 (235 days ago) in Sculptor

234.

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 (234 days ago) in Aquarius

235.

Close approach of the Moon and Saturn The Moon and Saturn pass close to each other. Tue, 26 Sep 2023 at 23:12 EDT (234 days ago) in Aquarius

236.

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 (233 days ago) in Aquarius

237.

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 (233 days ago) in Tucana

238.

Daytime Sextantid meteor shower 2023 The Daytime Sextantid meteor shower reaches its peak. Wed, 27 Sep 2023 (232 days ago) in Sextans

239.

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 (233 days ago) in Aquarius

240.

Full Moon The Moon reaches full phase and is visible for much of the night. Fri, 29 Sep 2023 at 05:57 EDT (231 days ago) in Pisces