Asteroid 15 Eunomia is one of the largest asteroids in the main asteroid belt, with a diameter of about 270 kilometers. It was discovered on July 29, 1851, by the Italian astronomer Annibale de Gasparis. The asteroid was named after Eunomia, the Greek goddess of law and order. Eunomia orbits the Sun at a distance of about 2.64 astronomical units (AU), with an orbital period of about 4.38 years. Eunomia is classified as an S-type asteroid, indicating that its surface is likely composed of silicate materials. Astronomers have observed that Eunomia has a small moon, which has a diameter of about 4 kilometers and orbits at a distance of approximately 110 kilometers from the asteroid's center.
Asteroid 15 Eunomia Position Calculator
Compute the position of Asteroid 15 Eunomia for any date and time between 1 January 1900 and 31 December 2099 and visualize the results on an interactive sky map.
In Evidence
Asteroid 15 Eunomia
Asteroid 15 Eunomia is in the constellation of
Gemini,
at a distance of
Finder Charts
View interactive star map
High precision deep sky finder chart, 60 arcmin wide, showing where Asteroid 15 Eunomia is right now. Click on the image to see a more detailed fullscreen tracker view.
Also check out Where is Asteroid 15 Eunomia?, a page that provides all the information needed to find Asteroid 15 Eunomia in the sky and additional links to sky charts.
Celestial Coordinates
Apparent
J2000
Additional Information
Rise and Set Times
Today's rise, transit and set times of Asteroid 15 Eunomia from Greenwich, UK (all times relative to the local timezone Europe/London):
- 15 Eunomia is below the horizon from Greenwich, UK.
- Given its current magnitude, 15 Eunomia is visible with the help of a binocular with a 70-80mm aperture or a small telescope.
- Go to interactive sky chart
If you need to access this information frequently for your observations, you can create a simple customized Quick Access page, so that you can easily bookmark it in your browser favorites or add a shortcut to your mobile phones' home screen.
Distance from Earth
The distance of Asteroid 15 Eunomia from Earth is currently
The following chart shows the distance of Asteroid 15 Eunomia from Earth as a function of time. In the chart the distance data is measured in Astronomical Units and sampled with an interval of 1 day.
The value of the reported distance might be somewhat inaccurate around the times of closest approach for objects passing extremely close to Earth. The value of the distance of 15 Eunomia from Earth is also available as a real time updated value in the Live Position and Data Tracker.
Closest Approach
Between 1 January 1900 and 31 December 2099, the closest approach of Asteroid 15 Eunomia to Earth happens on Sat Oct 24 2071 at a distance of 1.190320 Astronomical Units, or 178,069,374 kilometers:
NOTE: values for the closest approach are computed with a sampling interval of 1 day.
Light Curve
The following chart is the predicted light curve (visual magnitude as a function of time) of Asteroid 15 Eunomia, according to the most recent ephemerides data. Magnitude data is sampled with a 2 days interval and there might be inaccuracies for objects changing brightness very rapidly during the course of a few days. For comets there could be large discrepancies between the observed and predicted brightness because of their highly dynamic behaviour.
Orbital Elements
The following table lists the orbital elements of Asteroid 15 Eunomia at epoch 24 February 2023 00:00 UTC (JD: 2460000.5). Source: JPL Small-Body Database
| Element | Symbol | Value |
|---|---|---|
| Orbit eccentricity | e | 0.18700976 |
| Orbit inclination | i | 11.75360648° |
| Perihelion distance | q | 2.14877925 AU 321,452,801 km |
| Aphelion distance | Q |
3.13733404 AU 469,338,492 km |
| Semi-major axis | a |
2.64305664 AU 395,395,647 km |
| Orbital period | period |
4.2970 years 1,569.4885 days |
| Date of perihelion transit | Tp | 2024-Jul-14 02:11:40 2,460,505.5914 JD |
| Next perihelion transit | 2028-Oct-30 13:55 2,462,075.0799 JD |
|
| Argument of perihelion | peri | 98.713244720149° |
| Longitude of the ascending node | node | 292.90826165525° |
| Mean anomaly | M | 244.14510652076° |
| Mean motion | n | 0.22937410°/day |
View Asteroid 15 Eunomia in the 3D Solar System Simulator
Physical Data
The following shows the known values of the most important physical parameters of Asteroid 15 Eunomia. Source: JPL Small-Body Database
| Physical Parameter | Value | Relative to Earth |
|---|---|---|
| Diameter | 255.33 km | 0.0200 |
| Sideral Rotation | 6.0830 hours | 0.2542 |
| Absolute Magnitude | 5.28 | |
| Geometric Albedo | 0.2094 |
15 Days Ephemeris
The following table lists the ephemerides of Asteroid 15 Eunomia 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 |
|---|---|---|---|---|
| 2025 May 12 | 07h 00m 33s | +21° 06’ 00” | 10.68 | Gemini |
| 2025 May 13 | 07h 02m 12s | +21° 01’ 24” | 10.69 | Gemini |
| 2025 May 14 | 07h 03m 52s | +20° 56’ 46” | 10.70 | Gemini |
| 2025 May 15 | 07h 05m 31s | +20° 52’ 04” | 10.70 | Gemini |
| 2025 May 16 | 07h 07m 11s | +20° 47’ 18” | 10.71 | Gemini |
| 2025 May 17 | 07h 08m 51s | +20° 42’ 30” | 10.71 | Gemini |
| 2025 May 18 | 07h 10m 31s | +20° 37’ 38” | 10.72 | Gemini |
| 2025 May 19 | 07h 12m 11s | +20° 32’ 43” | 10.72 | Gemini |
| 2025 May 20 | 07h 13m 51s | +20° 27’ 44” | 10.73 | Gemini |
| 2025 May 21 | 07h 15m 31s | +20° 22’ 42” | 10.73 | Gemini |
| 2025 May 22 | 07h 17m 10s | +20° 17’ 36” | 10.74 | Gemini |
| 2025 May 23 | 07h 18m 51s | +20° 12’ 28” | 10.74 | Gemini |
| 2025 May 24 | 07h 20m 31s | +20° 07’ 15” | 10.75 | Gemini |
| 2025 May 25 | 07h 22m 12s | +20° 02’ 00” | 10.75 | Gemini |
Additional Resources on TheSkyLive
- Asteroid 15 Eunomia: Complete reference information on TheSkyLive.com
- Where is Asteroid 15 Eunomia?: Key information on locating Asteroid 15 Eunomia in the sky.
- Distance from Earth: Find out how far Asteroid 15 Eunomia is from Earth right now.
- How Bright is Asteroid 15 Eunomia?: Current visual brightness (magnitude) and apparent size.
- Rise and Set Times: Asteroid 15 Eunomia's rise and set times from your location.
- Interactive Sky Map: planetarium-style interactive visualization of Asteroid 15 Eunomia's position in the sky.
- Live Position Tracker: high precision position tracker with deep space imagery.
- Ephemeris: 15 days Asteroid 15 Eunomia's computed ephemeris.
- Orbital elements: information about Asteroid 15 Eunomia orbital parameters.
- Orbit Visualization. 3d interactive visualization showing the orbit of Asteroid 15 Eunomia with respect to the major Solar System objects.
- Physical Data. Detailed information about physical properties of Asteroid 15 Eunomia, such as mass and geometric properties.