21.

The Moon at perigee The Moon appears large as it makes its closest approach to the Earth. Mon, 24 Dec 2018 at 04:49 EDT (567 days ago) in Gemini

22.

Ursid meteor shower The Ursid meteor shower reaches its peak. Sat, 22 Dec 2018 (569 days ago) in Ursa Minor

23.

Full Moon The Moon is visible for much of the night. Sat, 22 Dec 2018 at 12:49 EDT (569 days ago) in Orion

24.

The Moon at aphelion The Moon reaches its furthest point from the Sun. Fri, 21 Dec 2018 at 21:21 EDT (570 days ago) in Taurus

25.

December solstice 21 December will be the shortest day of 2018 in the northern hemisphere. Fri, 21 Dec 2018 at 17:08 EDT (570 days ago) in Sagittarius

26.

Conjunction of Jupiter and Mercury Jupiter and Mercury share the same right ascension, at a separation of 0°51'. Fri, 21 Dec 2018 at 09:40 EDT (570 days ago) in Ophiuchus

27.

December Leonis Minorid meteor shower The December Leonis Minorid meteor shower reaches its peak. Thu, 20 Dec 2018 (571 days ago) in Leo Minor

28.

Asteroid 433 Eros at opposition Asteroid 433 Eros is well placed for observation. Tue, 18 Dec 2018 at 06:58 EDT (573 days ago) in Camelopardalis

29.

46P/Wirtanen reaches its brightest 46P/Wirtanen is well placed for observation. Sun, 16 Dec 2018 (575 days ago) in Taurus

30.

Comae Berenicid meteor shower The Comae Berenicid meteor shower reaches its peak. Sun, 16 Dec 2018 (575 days ago) in Leo

31.

Mercury at greatest elongation west Mercury is bright and well placed in the dawn sky. Sat, 15 Dec 2018 at 10:16 EDT (576 days ago) in Scorpius

32.

Moon at First Quarter The Moon appears high in the sky at sunset and sets in the west at around midnight. Sat, 15 Dec 2018 at 06:49 EDT (576 days ago) in Aquarius

33.

Close approach of the Moon and Mars The Moon and Mars pass within 3°21' of each other. Fri, 14 Dec 2018 at 20:52 EDT (577 days ago) in Aquarius

34.

Conjunction of the Moon and Mars The Moon and Mars share the same right ascension, at a separation of 3°33'. Fri, 14 Dec 2018 at 18:22 EDT (577 days ago) in Aquarius

35.

Mercury reaches highest point in morning sky Mercury is bright and well placed in the dawn sky. Fri, 14 Dec 2018 (577 days ago) in Scorpius

36.

Geminid meteor shower The Geminid meteor shower reaches its peak. Fri, 14 Dec 2018 (577 days ago) in Gemini

37.

Venus reaches highest point in morning sky Venus is bright and well placed in the dawn sky. Fri, 14 Dec 2018 (577 days ago) in Libra

38.

46P/Wirtanen at perihelion 46P/Wirtanen makes its closest approach to the Sun. Thu, 13 Dec 2018 (578 days ago) in Taurus

39.

The Moon at apogee The Moon appears small as it recedes to its furthest point from the Earth. Wed, 12 Dec 2018 at 07:24 EDT (579 days ago) in Capricornus

40.

σ-Hydrid meteor shower The σ-Hydrid meteor shower reaches its peak. Wed, 12 Dec 2018 (579 days ago) in Hydra