Asteroid 13 Egeria is a relatively large asteroid with a diameter of approximately 214 kilometers. It was discovered on November 2, 1850, by Italian astronomer Annibale de Gasparis and named after the Roman goddess Egeria, who was associated with wisdom and prophecy. The asteroid orbits the Sun between Mars and Jupiter, with a semi-major axis of approximately 2.66 astronomical units (AU) and an orbital period of about 4.45 years. Egeria's orbit is moderately eccentric and inclined compared to other asteroids in the main belt. It rotates relatively slowly, with a rotation period of about 14.1 hours. Egeria is also classified as a C-type asteroid, indicating that its surface is likely rich in carbonaceous materials. It is relatively bright and can be observed with a small telescope under favorable conditions.
Find it in the Sky
Chose a date & time and view the position of asteroid 13 Egeria in the sky on our interactive planetarium.
In Evidence
Asteroid 13 Egeria
Asteroid 13 Egeria is in the constellation of Cancer, at a distance of
Finder Charts
The sky charts below show, at different resolutions, the position of asteroid 13 Egeria in the sky. Click on each chart to access the interactive star map tool.
The following map uses photographic imagery from the Digitized Sky Survey (DSS) to realistically visualize the precise position of asteroid 13 Egeria against the stars in the background. The horizontal size of the map measures 60 arcminutes. Click on the image to access a more detailed full-screen view.
Equatorial Coordinates
Apparent
J2000
Additional Information
Rise and Set Times
The following table lists today's rise, transit and set times of asteroid 13 Egeria from Greenwich, UK (all times relative to the local timezone Europe/London):
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Distance from Earth
The distance of asteroid 13 Egeria from Earth is currently
The following graph shows the distance of asteroid 13 Egeria from Earth as a function of time. In the chart the distance is measured in Astronomical Units and the data is sampled with an interval of 1 day.
Note: The values in this chart may not be entirely accurate around the time of closest approach for objects passing very close to Earth at high speed (e.g., Near-Earth Objects).
The value of the distance of 13 Egeria from Earth is also available as a real time updated value in the live position tracker.
Closest Approach to Earth
In the period between January 1, 1900 and December 31, 2099, the closest approach of asteroid 13 Egeria to Earth happened on Friday 14 January 1955 at a distance of 1.428381 Astronomical Units, or 213,682,816 kilometers:
Note: the values for the closest approach are computed with a sampling interval of 1 day.
Light Curve
The following chart shows the light curve of asteroid 13 Egeria, i.e., its apparent magnitude as a function of time. The curve is calculated using the latest ephemerides provided by JPL Horizons. The magnitude data is sampled with the interval of 2 days. Because of this sampling, inaccuracies may occur for objects that have large variations of brightness over a few days. For comets, large discrepancies can arise between the calculated brightness and the observations due to their highly dynamic, and not always precisely predictable, behavior.
Orbital Elements
The following table lists the orbital elements of asteroid 13 Egeria at epoch February, 24 2023 00:00 UTC (JD: 2460000.5). Source: JPL Small-Body Database
| Element | Symbol | Value |
|---|---|---|
| Orbit eccentricity | e | 0.08561105 |
| Orbit inclination | i | 16.53667695° |
| Perihelion distance | q | 2.35507774 AU 352,314,615 km |
| Aphelion distance | Q |
2.79607316 AU 418,286,592 km |
| Semi-major axis | a |
2.57557545 AU 385,300,604 km |
| Orbital period | period |
4.1335 years 1,509.7667 days |
| Date of perihelion transit | Tp | April 17, 2021 2,459,321.7818 JD |
| Next perihelion transit | June 5, 2025 2,460,831.5485 JD |
|
| Argument of perihelion | peri | 79.906107517124° |
| Longitude of the ascending node | node | 43.208385237831° |
| Mean anomaly | M | 161.8386226222° |
| Mean motion | n | 0.23844744°/day |
Orbit Visualization
The following chart is a 3D animated visualization of the orbit of asteroid 13 Egeria relative to the other major objects in the Solar System. You can access more advanced features using our 3D Solar System Viewer.
Physical Properties
The table below lists the known key physical properties of asteroid 13 Egeria. The source for this data is the JPL Small-Body Database.
| Physical Parameter | Value | Relative to Earth |
|---|---|---|
| Diameter | 207.64 km | 0.0163 |
| Sideral Rotation | 7.0450 hours | 0.2943 |
| Absolute Magnitude | 6.74 | |
| Geometric Albedo | 0.0825 |
15 Days Ephemeris
The following table lists the ephemerides of asteroid 13 Egeria computed for the past and next 7 days, with a 24 hours interval. Apparent celestial coordinates are provided.
| Date | Right AscensionR.A. | DeclinationDec. | MagnitudeMag | Constellation |
|---|---|---|---|---|
| Jul 10 2025 | 08h 44m 58s | +30° 17’ 49” | 12.00 | Cancer |
| Jul 11 2025 | 08h 47m 07s | +30° 09’ 18” | 11.99 | Cancer |
| Jul 12 2025 | 08h 49m 16s | +30° 00’ 43” | 11.99 | Cancer |
| Jul 13 2025 | 08h 51m 24s | +29° 52’ 02” | 11.99 | Cancer |
| Jul 14 2025 | 08h 53m 31s | +29° 43’ 17” | 11.98 | Cancer |
| Jul 15 2025 | 08h 55m 39s | +29° 34’ 27” | 11.98 | Cancer |
| Jul 16 2025 | 08h 57m 46s | +29° 25’ 32” | 11.97 | Cancer |
| Jul 17 2025 | 08h 59m 54s | +29° 16’ 33” | 11.97 | Cancer |
| Jul 18 2025 | 09h 02m 01s | +29° 07’ 28” | 11.96 | Cancer |
| Jul 19 2025 | 09h 04m 07s | +28° 58’ 20” | 11.96 | Cancer |
| Jul 20 2025 | 09h 06m 13s | +28° 49’ 07” | 11.95 | Cancer |
| Jul 21 2025 | 09h 08m 20s | +28° 39’ 48” | 11.95 | Cancer |
| Jul 22 2025 | 09h 10m 26s | +28° 30’ 26” | 11.95 | Cancer |
| Jul 23 2025 | 09h 12m 31s | +28° 21’ 00” | 11.94 | Cancer |
Additional Resources on TheSkyLive
- Asteroid 13 Egeria: Complete reference information on TheSkyLive.com.
- Where is asteroid 13 Egeria?: Key information on where to find asteroid 13 Egeria in the sky.
- Distance of asteroid 13 Egeria from Earth: Find out how far asteroid 13 Egeria is from Earth right now.
- How Bright is asteroid 13 Egeria?: Current visual brightness (magnitude) and apparent size.
- Rise and Set Times: Rise and set times of asteroid 13 Egeria from your location.
- Interactive Sky Map: Planetarium-style interactive visualization of asteroid 13 Egeria's position in the sky.
- Live Position Tracker: High precision real time tracker of asteroid 13 Egeria's position using deep space imagery.
- Ephemeris: 15 days asteroid 13 Egeria's computed ephemeris.
- Orbital elements: Information about asteroid 13 Egeria orbital parameters.
- Orbit Visualization: 3D interactive visualization showing the orbit of asteroid 13 Egeria with respect to the major Solar System objects.
- Physical Data: Detailed information about physical properties of asteroid 13 Egeria.