21.

September equinox Day and night have equal length, marking the beginning of autumn in the northern hemisphere and spring in the southern hemisphere. Sun, 22 Sep 2013 at 16:48 EDT (3,900 days ago) in Virgo

22.

1 Ceres at perihelion 1 Ceres passes its orbit's closest point to the Sun. Sun, 22 Sep 2013 at 13:37 EDT (3,900 days ago) in Leo

23.

136472 Makemake at solar conjunction 136472 Makemake is unobservable as it passes around the far side of the Sun – marking the end of one apparition and the beginning of the next. Sun, 22 Sep 2013 at 06:07 EDT (3,900 days ago) in Coma Berenices

24.

Conjunction of Venus and Saturn Venus and Saturn share the same right ascension, at a separation of 3°45'. Thu, 19 Sep 2013 at 20:17 EDT (3,903 days ago) in Libra

25.

Full Moon The Moon reaches full phase and is visible for much of the night. Thu, 19 Sep 2013 at 07:12 EDT (3,903 days ago) in Pisces

26.

Close approach of Venus and Saturn Venus and Saturn pass within 3°28' of each other. Wed, 18 Sep 2013 at 11:54 EDT (3,904 days ago) in Libra

27.

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. Tue, 17 Sep 2013 at 05:21 EDT (3,905 days ago) in Aquarius

28.

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. Sun, 15 Sep 2013 at 12:30 EDT (3,907 days ago) in Capricornus

29.

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. Thu, 12 Sep 2013 at 13:08 EDT (3,910 days ago) in Ophiuchus

30.

Lunar occultation of Beta1 Scorpii The Moon will pass in front of Beta1 Scorpii (Acrab), creating a lunar occultation visible from Mongolia and Russia. Wed, 11 Sep 2013 at 08:17 EDT (3,911 days ago) in Scorpius

31.

Conjunction of the Moon and Saturn The Moon and Saturn share the same right ascension, at a separation of 2°21'. Mon, 09 Sep 2013 at 13:08 EDT (3,913 days ago) in Libra

32.

Close approach of the Moon and Saturn The Moon and Saturn pass close to each other. Mon, 09 Sep 2013 at 12:09 EDT (3,913 days ago) in Libra

33.

Asteroid 324 Bamberga at opposition Asteroid 324 Bamberga makes closest approach to the Earth. Mon, 09 Sep 2013 at 07:58 EDT (3,913 days ago) in Pisces

34.

September ε-Perseid meteor shower 2013 The September ε-Perseid meteor shower reaches its peak. Mon, 09 Sep 2013 (3,913 days ago) in Perseus

35.

Close approach of Mars and M44 Mars and M44 pass close to each other. Sun, 08 Sep 2013 at 18:37 EDT (3,914 days ago) in Cancer

36.

Conjunction of the Moon and Venus The Moon and Venus share the same right ascension, at a separation of 25'. Sun, 08 Sep 2013 at 17:04 EDT (3,914 days ago) in Virgo

37.

Lunar occultation of Venus The Moon will pass in front of Venus, creating a lunar occultation visible from countries and territories including Argentina, Chile, Brazil and Uruguay amongst others. Sun, 08 Sep 2013 at 16:51 EDT (3,914 days ago) in Virgo

38.

Close approach of the Moon and Venus The Moon and Venus pass close to each other. Sun, 08 Sep 2013 at 16:51 EDT (3,914 days ago) in Virgo

39.

Lunar occultation of Spica The Moon will pass in front of Spica (Alpha Virginis), creating a lunar occultation visible from countries and territories including Saudi Arabia, Sudan, Yemen and Ethiopia amongst others. Sun, 08 Sep 2013 at 10:55 EDT (3,914 days ago) in Virgo

40.

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. Sat, 07 Sep 2013 at 11:18 EDT (3,915 days ago) in Virgo