401.

Lunar occultation of Aldebaran The Moon will pass in front of Aldebaran (Alpha Tauri), creating a lunar occultation visible from countries and territories including the Contiguous United States, Canada, Mexico and Alaska amongst others. Tue, 12 Sep 2017 at 08:26 EDT (2,500 days ago) in Taurus

402.

Mercury at greatest elongation west Mercury is bright and well placed in the dawn sky. Tue, 12 Sep 2017 at 05:19 EDT (2,500 days ago) in Leo

403.

Close approach of the Moon and Collinder 50 The Moon and Collinder 50 pass close to each other. Tue, 12 Sep 2017 at 04:42 EDT (2,500 days ago) in Taurus

404.

Comet 1I/`Oumuamua passes perihelion Comet 1I/`Oumuamua makes its closest approach to the Sun. Sat, 09 Sep 2017 (2,503 days ago) in Leo

405.

September ε-Perseid meteor shower 2017 The September ε-Perseid meteor shower reaches its peak. Sat, 09 Sep 2017 (2,503 days ago) in Perseus

406.

Asteroid 89 Julia at opposition Asteroid 89 Julia makes closest approach to the Earth. Thu, 07 Sep 2017 at 17:34 EDT (2,505 days ago) in Pegasus

407.

Full Moon The Moon reaches full phase and is visible for much of the night. Wed, 06 Sep 2017 at 03:02 EDT (2,506 days ago) in Aquarius

408.

Lunar occultation of Neptune The Moon will pass in front of Neptune, creating a lunar occultation visible from countries and territories including Antarctica, Argentina, Chile and Brazil amongst others. Wed, 06 Sep 2017 at 00:59 EDT (2,506 days ago) in Aquarius

409.

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, 05 Sep 2017 at 01:19 EDT (2,507 days ago) in Aquarius

410.

Supernova SN2017gmr discovered A new supernova has been discovered in NGC 988. Sun, 03 Sep 2017 (2,508 days ago)

411.

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. Sun, 03 Sep 2017 at 13:06 EDT (2,509 days ago) in Capricornus

412.

Supernova SN2017glx discovered A new supernova has been discovered in NGC 6824. Sat, 02 Sep 2017 (2,509 days ago)

413.

Supernova SN2017glq discovered A new supernova has been discovered in IC 208. Fri, 01 Sep 2017 (2,510 days ago)

414.

Close approach of Venus and M44 Venus and M44 pass close to each other. Fri, 01 Sep 2017 at 09:47 EDT (2,511 days ago) in Cancer

415.

Aurigid meteor shower 2017 The Aurigid meteor shower reaches its peak. Thu, 31 Aug 2017 (2,511 days ago) in Auriga

416.

Close approach of the Moon and Saturn The Moon and Saturn pass close to each other. Wed, 30 Aug 2017 at 10:49 EDT (2,513 days ago) in Ophiuchus

417.

Conjunction of the Moon and Saturn The Moon and Saturn share the same right ascension, at a separation of 3°33'. Wed, 30 Aug 2017 at 10:02 EDT (2,513 days ago) in Ophiuchus

418.

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. Wed, 30 Aug 2017 at 07:24 EDT (2,513 days ago) in Ophiuchus

419.

Asteroid 3122 Florence at opposition Asteroid 3122 Florence makes closest approach to the Earth. Wed, 30 Aug 2017 at 00:46 EDT (2,513 days ago) in Capricornus

420.

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. Tue, 29 Aug 2017 at 04:13 EDT (2,514 days ago) in Scorpius