Astronomical Algorithms Sky events computed for 2025

Astronomy calendar 2025

The 95 computed sky events of 2025: oppositions, conjunctions and greatest elongations of the planets, the start and end of every retrograde period, the four phases of the Moon, the equinoxes and the solstices.

2025 2026 ›

Highlights of 2025

All dates and times are in Universal Time (UTC). Subtract or add your time zone offset: an event late in the evening UTC falls on the next calendar day east of Greenwich.

2025 month by month

JanuaryFebruaryMarchAprilMayJuneJulyAugustSeptemberOctoberNovemberDecember

January 2025

Date UTC Event Details
– Earth at perihelion Closest to the Sun: 0.9833 AU (147.1 million km).
23:56 First quarter
– Venus at greatest elongation east 47.2° east of the Sun: best evening visibility.
22:27 Full Moon 381,406 km from Earth.
– Mars at opposition Opposite the Sun, visible all night. 0.644 AU from Earth (96.3 million km).
20:31 Last quarter
12:36 New Moon 374,266 km from Earth.
– Uranus turns direct Stationary in Aries, then resumes its eastward motion.

February 2025

Date UTC Event Details
– Jupiter turns direct Stationary in Taurus, then resumes its eastward motion.
08:02 First quarter
– Mercury at superior conjunction On the far side of the Sun, 1.393 AU from Earth. Not observable.
13:53 Full Moon 392,621 km from Earth.
17:33 Last quarter
– Mars turns direct Stationary in Gemini, then resumes its eastward motion.
00:45 New Moon 364,694 km from Earth.

March 2025

Date UTC Event Details
– Venus turns retrograde Stationary in Pisces, then moves westward against the stars.
16:32 First quarter
– Mercury at greatest elongation east 18.2° east of the Sun: best evening visibility.
– Saturn in conjunction with the Sun Behind the Sun as seen from Earth, not observable. 10.602 AU from Earth.
06:55 Full Moon 401,499 km from Earth.
– Mercury turns retrograde Stationary in Pisces, then moves westward against the stars.
– Neptune in conjunction with the Sun Behind the Sun as seen from Earth, not observable. 30.888 AU from Earth.
09:01 March equinox Day and night of equal length. Spring begins in the northern hemisphere, autumn in the southern.
11:29 Last quarter
– Venus at inferior conjunction Passes between Earth and the Sun, 0.281 AU from Earth. Not observable.
– Mercury at inferior conjunction Passes between Earth and the Sun, 0.606 AU from Earth. Not observable.
10:58 New Moon 358,694 km from Earth.

April 2025

Date UTC Event Details
02:15 First quarter
– Mercury turns direct Stationary in Pisces, then resumes its eastward motion.
00:22 Full Moon 406,006 km from Earth.
– Venus turns direct Stationary in Pisces, then resumes its eastward motion.
01:35 Last quarter
– Mercury at greatest elongation west 27.4° west of the Sun: best morning visibility.
19:31 New Moon 357,141 km from Earth.

May 2025

Date UTC Event Details
13:52 First quarter
16:56 Full Moon 405,279 km from Earth.
– Uranus in conjunction with the Sun Behind the Sun as seen from Earth, not observable. 20.541 AU from Earth.
11:59 Last quarter
03:02 New Moon 360,042 km from Earth.
– Mercury at superior conjunction On the far side of the Sun, 1.322 AU from Earth. Not observable.

June 2025

Date UTC Event Details
– Venus at greatest elongation west 45.9° west of the Sun: best morning visibility.
03:41 First quarter
07:44 Full Moon 399,743 km from Earth.
19:19 Last quarter
02:42 June solstice The Sun reaches its northernmost point. Longest day in the northern hemisphere, shortest in the southern.
– Jupiter in conjunction with the Sun Behind the Sun as seen from Earth, not observable. 6.159 AU from Earth.
10:32 New Moon 366,783 km from Earth.

July 2025

Date UTC Event Details
19:30 First quarter
– Earth at aphelion Farthest from the Sun: 1.0166 AU (152.1 million km).
– Mercury at greatest elongation east 25.9° east of the Sun: best evening visibility.
– Neptune turns retrograde Stationary in Pisces, then moves westward against the stars.
20:37 Full Moon 390,732 km from Earth.
– Saturn turns retrograde Stationary in Pisces, then moves westward against the stars.
00:38 Last quarter
– Mercury turns retrograde Stationary in Cancer, then moves westward against the stars.
19:11 New Moon 376,293 km from Earth.
– Mercury at inferior conjunction Passes between Earth and the Sun, 0.595 AU from Earth. Not observable.

August 2025

Date UTC Event Details
12:41 First quarter
07:55 Full Moon 380,056 km from Earth.
– Mercury turns direct Stationary in Cancer, then resumes its eastward motion.
05:12 Last quarter
– Mercury at greatest elongation west 18.6° west of the Sun: best morning visibility.
06:06 New Moon 387,058 km from Earth.
06:25 First quarter

September 2025

Date UTC Event Details
– Uranus turns retrograde Stationary in Taurus, then moves westward against the stars.
18:09 Full Moon 369,673 km from Earth.
– Mercury at superior conjunction On the far side of the Sun, 1.379 AU from Earth. Not observable.
10:33 Last quarter
– Saturn at opposition Opposite the Sun, visible all night. 8.547 AU from Earth (1,278.6 million km).
19:54 New Moon 397,121 km from Earth.
18:19 September equinox Day and night of equal length. Autumn begins in the northern hemisphere, spring in the southern.
– Neptune at opposition Opposite the Sun, visible all night. 28.884 AU from Earth (4,321.0 million km).
23:54 First quarter

October 2025

Date UTC Event Details
03:48 Full Moon 361,460 km from Earth.
18:13 Last quarter
12:25 New Moon 404,287 km from Earth.
16:21 First quarter
– Mercury at greatest elongation east 23.9° east of the Sun: best evening visibility.

November 2025

Date UTC Event Details
13:19 Full Moon 356,980 km from Earth.
– Mercury turns retrograde Stationary in Scorpius, then moves westward against the stars.
– Jupiter turns retrograde Stationary in Gemini, then moves westward against the stars.
05:28 Last quarter
06:47 New Moon 406,681 km from Earth.
– Mercury at inferior conjunction Passes between Earth and the Sun, 0.678 AU from Earth. Not observable.
– Uranus at opposition Opposite the Sun, visible all night. 18.509 AU from Earth (2,768.9 million km).
– Saturn turns direct Stationary in Pisces, then resumes its eastward motion.
06:59 First quarter
– Mercury turns direct Stationary in Libra, then resumes its eastward motion.

December 2025

Date UTC Event Details
23:14 Full Moon 357,218 km from Earth.
– Mercury at greatest elongation west 20.7° west of the Sun: best morning visibility.
– Neptune turns direct Stationary in Pisces, then resumes its eastward motion.
20:52 Last quarter
01:43 New Moon 403,494 km from Earth.
15:03 December solstice The Sun reaches its southernmost point. Shortest day in the northern hemisphere, longest in the southern.
19:10 First quarter

Full moons and new moons of 2025

Instant of each phase, when the Moon is exactly opposite the Sun (full) or in the same direction (new), with its distance from the centre of the Earth.

Full Moon UTC Distance New Moon UTC Distance
22:27 381,406 km from Earth. 12:36 374,266 km from Earth.
13:53 392,621 km from Earth. 00:45 364,694 km from Earth.
06:55 401,499 km from Earth. 10:58 358,694 km from Earth.
00:22 406,006 km from Earth. 19:31 357,141 km from Earth.
16:56 405,279 km from Earth. 03:02 360,042 km from Earth.
07:44 399,743 km from Earth. 10:32 366,783 km from Earth.
20:37 390,732 km from Earth. 19:11 376,293 km from Earth.
07:55 380,056 km from Earth. 06:06 387,058 km from Earth.
18:09 369,673 km from Earth. 19:54 397,121 km from Earth.
03:48 361,460 km from Earth. 12:25 404,287 km from Earth.
13:19 356,980 km from Earth. 06:47 406,681 km from Earth.
23:14 357,218 km from Earth. 01:43 403,494 km from Earth.

How this calendar is computed

Nothing here is copied from an almanac. The positions of the planets come from the VSOP87 theory, the Moon from the lunar theory of Jean Meeus' Astronomical Algorithms, and each event is found by searching for the instant when a condition is met: the planet and the Sun at the same ecliptic longitude (conjunction) or 180° apart (opposition), the largest angle from the Sun (greatest elongation), or the day the motion in longitude reverses (start and end of a retrograde period).

Planetary events are given to the day. Moon phases, equinoxes and solstices are given to the minute and are good to about two minutes. Eclipses, occultations and meteor showers are not computed and are not listed.

Frequently asked questions

When are the equinoxes and solstices in 2025?

March equinox: March 20 at 09:01 UTC. June solstice: June 21 at 02:42 UTC. September equinox: September 22 at 18:19 UTC. December solstice: December 21 at 15:03 UTC.

Which planets reach opposition in 2025?

Mars on January 16, Saturn on September 21, Neptune on September 23 and Uranus on November 21. At opposition a planet is opposite the Sun in the sky: it rises at sunset, is highest around midnight, and is at its closest and brightest for the year.

How many full moons are there in 2025?

There are 12 full moons in 2025: January 13, February 12, March 14, April 13, May 12, June 11, July 10, August 9, September 7, October 7, November 5, December 4 (dates in Universal Time).

When is Mercury retrograde in 2025?

Mercury is retrograde from March 15 to April 7, from July 18 to August 11 and from November 9 to November 29. The page on Mercury retrograde gives the details of each period.

Computed with Laurent Remond's implementation of Jean Meeus, Astronomical Algorithms (2nd ed., Willmann-Bell, 1998).