Observation details: asteroid Eos
Daily motion of Eos
221 Eos will remain visible until March 28, when it moves too close to the Sun and temporarily disappears from the night sky.
Eos visibility on 2026-10-18
Eos Visible from before midnight until sunrise
Eos rise and set timetable
| Time | Elevation | |
Moonrise, 34.6% illuminated  | 11:59 | -52° |
| Astronomical observing session begins | 17:54 | -4° |
| Eos rise | 18:15 | |
| Moonset | 21:28 | 37° |
| Eos transit | 00:14 | 53° |
| Astronomical observing session ends | 03:51 | 28° |
| Twilight end (−12°) | 04:22 | 22° |
| Civil sunrise | 04:52 | 16° |
| Sunrise | 05:20 | 11° |
| Eos set | 06:14 |
Track Eos position throughout the night
← 18 October 2026 →
| Time | |
| Altitude | |
| Azimuth |
Shift the map to change the time and observe Eos changing position in the night sky.
Eos Description
This asteroid is designated 221 Eos, main-belt asteroid Its diameter is approximately 96 km. 221 Eos completes an orbit around the Sun in 5.2 years. It is currently 1.899 AU (284,031,005 km) from Earth, and is located in the constellation Cetus.Current position in the Solar System: Eos
| Date | Sun, 18 October 2026 |
| Distance from Earth | 1.89734 AU (283,838,024km) |
| Elongation | 157° |
| Angular diameter | " |
| Magnitude | 11.9 |
Finder Chart for
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| Object name | |
| Field of view | |
| Limiting magnitude | |
| coordinates | 2.91365, 0.22964 |
| Center coordinates | 2.91365, 0.22964 |
Annual motion of Eos
| Date | Sun, 18 October 2026 |
| Twilight start | 17:50 |
| Twilight end | 03:45 |
| Twilight duration | 10h 55m |
| Rise | 18:15 |
| Set | 06:13 |
| Elevation at transit | 53° |
| Transit time | 00:14 |
| Equatorial coordinates | RA: 02h 54m 08s", Dec: 00° 07' 50s |
| Magnitude | 12 |
| Constellation | Cetus |
The graph summarizes the object’s annual visibility, daily observing windows and transit times.
The vertical axis shows time of day and the horizontal axis shows the days of the year.
The shaded area marks when the object is above the horizon; the white line marks daily transit. You can also view the detailed annual visibility table.
The vertical axis shows time of day and the horizontal axis shows the days of the year.
The shaded area marks when the object is above the horizon; the white line marks daily transit. You can also view the detailed annual visibility table.
Astrometric and Physical Parameters of 221 Eos
Coordinates and Visibility
| Right Ascension | 02h 54m 49s |
| Declination | 00° 13′ 47″ |
| Magnitude | 11.9 |
| Constellation | Cetus |
| Elevation | 10° |
| Azimuth | 262.6° |
Acknowledgments
Orbital and small-body data are provided by NASA Jet Propulsion Laboratory (JPL) Small-Body Database (SBDB) and Center for Near-Earth Object Studies (CNEOS). These resources support accurate positions, orbits and physical characteristics.