Planets TonightMercury in 2021: brightness, position and events
Brightest-2.1around Aug 1
Closest (in table)0.563 au84 million km
Farthest1.451 au
Events this year12
Brightest last year-1.8
Events this year
| Date (JST) | Event | Mag | Dist (au) | Constellation | Elong. |
|---|---|---|---|---|---|
| 2021-01-24 10:56 | Greatest eastern elongation (evening) | -0.5 | 0.968 | Capricornus | 18.6° |
| 2021-02-08 22:47 | Inferior conjunction | +5.4 | 0.652 | Aquarius | 3.6° |
| 2021-03-06 20:22 | Greatest western elongation (morning) | +0.2 | 0.943 | Capricornus | 27.3° |
| 2021-04-19 10:49 | Superior conjunction | -2.3 | 1.331 | Aries | 0.6° |
| 2021-05-17 14:53 | Greatest eastern elongation (evening) | +0.4 | 0.834 | Taurus | 22.0° |
| 2021-06-11 10:12 | Inferior conjunction | +6.2 | 0.551 | Taurus | 3.1° |
| 2021-07-05 04:45 | Greatest western elongation (morning) | +0.3 | 0.842 | Taurus | 21.6° |
| 2021-08-01 23:07 | Superior conjunction | -2.0 | 1.342 | Cancer | 1.7° |
| 2021-09-14 13:24 | Greatest eastern elongation (evening) | +0.1 | 0.962 | Virgo | 26.8° |
| 2021-10-10 01:18 | Inferior conjunction | +6.1 | 0.662 | Virgo | 1.9° |
| 2021-10-25 14:29 | Greatest western elongation (morning) | -0.5 | 0.980 | Virgo | 18.4° |
| 2021-11-29 13:39 | Superior conjunction | -1.4 | 1.451 | Scorpius | 0.7° |
Magnitude through the year (lower = brighter)
Twice-monthly position and visibility
| Date | Mag | Dist (au) | Constellation | Elong. | Visibility |
|---|---|---|---|---|---|
| Jan 1 | -1.0 | 1.389 | Sagittarius | 7° E | Too close to the Sun |
| Jan 15 | -0.9 | 1.188 | Capricornus | 16° E | Evening sky |
| Feb 1 | +1.1 | 0.757 | Capricornus | 14° E | Too close to the Sun |
| Feb 15 | +2.1 | 0.668 | Aquarius | 14° W | Too close to the Sun |
| Mar 1 | +0.3 | 0.861 | Capricornus | 27° W | Morning sky |
| Mar 15 | +0.1 | 1.067 | Aquarius | 26° W | Morning sky |
| Apr 1 | -0.6 | 1.260 | Aquarius | 17° W | Morning sky |
| Apr 15 | -1.8 | 1.337 | Pisces | 4° W | Too close to the Sun |
| May 1 | -1.1 | 1.186 | Aries | 14° E | Too close to the Sun |
| May 15 | +0.2 | 0.878 | Taurus | 22° E | Evening sky |
| Jun 1 | +2.8 | 0.598 | Taurus | 14° E | Too close to the Sun |
| Jun 15 | +4.9 | 0.563 | Taurus | 7° W | Too close to the Sun |
| Jul 1 | +0.8 | 0.767 | Taurus | 21° W | Morning sky |
| Jul 15 | -0.7 | 1.076 | Gemini | 18° W | Morning sky |
| Aug 1 | -2.1 | 1.340 | Cancer | 2° W | Too close to the Sun |
| Aug 15 | -0.7 | 1.314 | Leo | 13° E | Too close to the Sun |
| Sep 1 | -0.1 | 1.145 | Virgo | 24° E | Evening sky |
| Sep 15 | +0.2 | 0.948 | Virgo | 27° E | Evening sky |
| Oct 1 | +1.4 | 0.703 | Virgo | 17° E | Evening sky |
| Oct 15 | +1.9 | 0.725 | Virgo | 11° W | Too close to the Sun |
| Nov 1 | -0.8 | 1.155 | Virgo | 16° W | Morning sky |
| Nov 15 | -0.9 | 1.378 | Libra | 8° W | Too close to the Sun |
| Dec 1 | -1.3 | 1.451 | Ophiuchus | 1° E | Too close to the Sun |
| Dec 15 | -0.9 | 1.391 | Sagittarius | 9° E | Too close to the Sun |
Computed with the JPL DE421 ephemeris and Skyfield (times in JST). Magnitude and distance are for 12:00 JST on each date. Visibility is a rough guide for mid-northern latitudes such as Japan.
About this page
Mercury is brightest around August 2021 (magnitude -2.1); 12 conjunctions, oppositions or elongations occur this year.