Mercury Observation Details
Mercury Daily Motion
Tonight, observing Mercury may prove challenging owing to its low elevation. It will reach its transit at by 08:49 and set before sunset at 13:41. Rising near twilight's end at 04:00, it will fade away by 04:16, peaking at just 3° above the horizon.Mercury will be visible until December, 29, when it will move too close to the Sun. During this time, its proximity to the Sun will cause it to disappear from the night sky, making it unobservable for a while.
Mercury Visibility Timetable on December 20
Mercury Rise and Set Timetable
| Time | Elevation | |
| Moon Rise, 0.4% illuminated | 05:19 | 14° |
| Mercury transit | 08:49 | 32° |
| Mercury set | 13:41 | |
| Moon Set | 14:25 | -8° |
| Astrosession begin | 16:26 | -31° |
| Astrosession end | 03:44 | -3° |
| Mercury rise | 04:00 | |
| Civil sunrise | 04:48 | 8° |
| Sunrise | 05:19 | 13° |
Track Mercury Position Throughout the Night
← Sat, 20 December 2025 →
| Time | |
| Altitude | |
| Azimuth |
Shift the map to change the time and observe Mercury changing position in the night sky.
Where is Mercury right now?
Mercury is located in the constellation Ophiuchus, at right ascension 16h 36m 10s" and declination -21° 06' 11s, approximately 1.24 AU (185,501,360 km) from Earth. Although it is currently above the horizon at an altitude of 31 degrees, Mercury is not visible because it is daytime.Upcoming Events
| Time | Description | Constellation |
|---|---|---|
| Thu, 22 January 2026, 14:00 | Capricornus | |
| Fri, 20 February 2026 | Greatest Elongation of Mercury | Pisces |
| Wed, 25 February 2026 | Retrograde motion of Mercury begins | Pisces |
| Sun, 8 March 2026, 14:00 | Pisces | |
| Thu, 19 March 2026 | Retrograde motion of Mercury ends | Aquarius |
Current position of Mercury in Solar System
| Date | Sat, 20 December 2025 |
| Distance from Earth to Mercury | 1.2438 AU (186,069,832km) |
| Elongation | 18° |
| Angular diameter | 5.4" |
| Magnitude | -0.5 |
Finder Chart for Mercury
Double-click to unlock the map.
| Object name | Mercury |
| Field of view | |
| Limiting magnitude | |
| Mercury coordinates | 16.60288, -21.10331 |
| Center coordinates | 16.60288, -21.10331 |
Mercury Passage Through Night
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Current position of Mercury
| Time | 08:13 |
| Latitude | 37.3541 |
| Longitude | -121.955 |
| Mercury elevation | 31° |
| Mercury Azimuth | -170° |
Here you can see the current position of the Mercury on the map, as well as its positions for rise and set. This tool allows you to track the Mercury's movement throughout the night, providing you with accurate and up-to-date information.
Annual motion of Mercury
| Date | Sat, 20 December 2025 |
| Twighlight start | 16:22 |
| Twighlight end | 03:37 |
| Twighlight duration | 11h 15m |
| Rise | 03:56 |
| Set | 13:37 |
| Elevation at transit | 31° |
| Transit time | 08:47 |
| Equatorial coordinates | RA: 16h 37m 36s", Dec: -21° 10' 57s |
| Magnitude | -1 |
| Constellation | Ophiuchus |
The graph illustrates the annual visibility pattern of a Mercury, providing a comprehensive overview of its daily appearances and transit times throughout the year.
The graph is structured with the vertical axis showing the hours of the day, ranging from 12 AM to 12 AM the next day, while the horizontal axis spans each day of the year.
The reddish shaded area indicates the periods when the Mercury is above the horizon, visible to observers. The white line marks the times when the celestial object reaches its highest point in the sky each day, known as the transit.
The graph is structured with the vertical axis showing the hours of the day, ranging from 12 AM to 12 AM the next day, while the horizontal axis spans each day of the year.
The reddish shaded area indicates the periods when the Mercury is above the horizon, visible to observers. The white line marks the times when the celestial object reaches its highest point in the sky each day, known as the transit.
Astrometric & Physical Parameters of Mercury
Coordinates & Visibility
| Right Ascension | 16.60288° |
| Declination | -21.10331° |
| Magnitude | -0.5 |
| Constellation | Ophiuchus |
| Elevation | 30.9° |
| Azimuth | -170.2° |
Basic Properties
| Mass, kg | 3.302E+23 |
| Mean density, g/cm³ | 5.427 |
Rotation
| Sidereal rotation period, days | 58.6463 d |
| Mean solar day, hours | 175.9421 d |
Surface & Atmosphere
| Surface gravity, m/s² | 3.701 |
| Escape velocity, km/s | 4.435 |
| Mean temperature, K | 440 |
Brightness
| Visual magnitude V(1,0) | -0.42 |
Data Acknowledgment
Our solar system data—including planetary physical and orbital parameters—comes from the Solar System OpenData API , maintained by Le Système Solaire. We thank Christophe and the contributors for making this open data available.