# 16070 Charops

**16070 Charops** (provisional designation 1999 RB\(_{101}\)) is a dark Jupiter Trojan asteroid approximately 64 kilometers (40 miles) in diameter, orbiting in the [Trojan](https://www.edgepedia.org/trojan-celestial-body) camp that librates around Jupiter's trailing L\(_5\) Lagrange point (orbital position where gravity balances, letting asteroids share Jupiter's orbit). It was discovered on 8 September 1999 by astronomers with the Lincoln Near-Earth Asteroid Research (LINEAR) program at Lincoln Laboratory's Experimental Test Site near Socorro, New Mexico, in the United States.<sup>[1](https://www.spacereference.org/asteroid/16070-charops-1999-rb101)</sup>

| Key fact | Detail |
|---|---|
| Orbit class | Jupiter Trojan (Trojan camp, L\(_5\)); JPL class code TJN, defined as asteroids trapped at Jupiter's L4/L5 Lagrange points with 4.6 au < a < 5.5 au and e < 0.3<sup>[2](https://ssd-api.jpl.nasa.gov/doc/sbdb_filter.html)</sup> |
| Orbital elements | Semi-major axis 5.149 AU, eccentricity 0.1271, inclination 16.23°<sup>[1](https://www.spacereference.org/asteroid/16070-charops-1999-rb101)</sup> |
| Orbital period | 4,270 days (11.69 years), ranging from 4.49 AU at perihelion to 5.80 AU at aphelion<sup>[1](https://www.spacereference.org/asteroid/16070-charops-1999-rb101)</sup> |
| Size | Mean diameter about 63.2 km (WISE 63.191 km, IRAS 64.13 km, Akari 68.98 km)<sup>[1](https://www.spacereference.org/asteroid/16070-charops-1999-rb101)</sup> |
| Rotation | 20.24 hours, with a lightcurve amplitude of 0.10 ± 0.01 magnitude<sup>[1](https://www.spacereference.org/asteroid/16070-charops-1999-rb101)</sup>  |

## Discovery and naming

**Naming.** The Iliad places Charops, son of Hippasos, among the Trojan-side fighters.<sup>[3](https://zenodo.org/records/2518303/files/article.pdf)</sup>

## Orbit

Charops shares Jupiter's orbit around the Sun, one of the swarms of small bodies clustered at the L\(_4\) and L\(_5\) Lagrange points 60 degrees ahead of and behind the planet.<sup>[1](https://www.spacereference.org/asteroid/16070-charops-1999-rb101)</sup><sup> • </sup><sup>[4](https://academic.oup.com/mnras/article/504/2/1571/6207955)</sup> It completes one revolution every 4,270 days, or 11.69 years, coming as close as 4.49 AU and receding as far as 5.80 AU from the Sun, with a semi-major axis of 5.149 AU and an inclination of 16.23°.<sup>[1](https://www.spacereference.org/asteroid/16070-charops-1999-rb101)</sup>

Its orbit keeps it far from Earth: the closest point of its orbit lies 3.48 AU from [Earth's orbit](https://www.edgepedia.org/earths-orbit), and orbital simulations by NASA JPL's Center for NEO Studies show no close approaches to Earth. For this reason JPL has not classified it as a potentially hazardous object, and it is not a near-Earth object.<sup>[1](https://www.spacereference.org/asteroid/16070-charops-1999-rb101)</sup>

The orbit is well constrained. Observations used in its orbit determination date back to 27 September 1954, the [Minor Planet Center](https://www.edgepedia.org/minor-planet-center) records 3,132 observations, and the object was last officially observed on 4 July 2023.<sup>[1](https://www.spacereference.org/asteroid/16070-charops-1999-rb101)</sup>

## Physical characteristics

Charops is a large Trojan: at about 63 km across it is larger than 99% of cataloged asteroids, comparable in size to the U.S. state of [Rhode Island](https://www.edgepedia.org/rhode-island), and it belongs to the 60 largest known [Jupiter Trojans](https://www.edgepedia.org/jupiter-trojans).<sup>[1](https://www.spacereference.org/asteroid/16070-charops-1999-rb101)</sup>

**Spectrum and albedo.** In SDSS-based taxonomy Charops is a dark D-type asteroid, a classification also assigned by the [Pan-STARRS](https://www.edgepedia.org/pan-starrs) survey, while the Collaborative Asteroid Lightcurve Link treats it as a C-type. Published geometric albedo values range from 0.045 ± 0.005 to 0.058 ± 0.009, consistent with the very dark surfaces typical of the Trojan population.<sup>[5](https://www-n.oca.eu/morby/papers/Rev39.pdf)</sup>

**Rotation.** Photometric observations by Daniel Coley and [Robert Stephens](https://www.edgepedia.org/robert-stephens) at GMARS and the Center for Solar System Studies in California produced several rotational lightcurves.

## Context among the Trojans

The Jovian Trojans number nearly 8,000 known co-orbital asteroids in the L\(_4\) and L\(_5\) swarms.<sup>[6](https://arxiv.org/abs/2101.04602)</sup> Members of the leading L\(_4\) swarm are named after Greek heroes of the Iliad and the trailing L\(_5\) swarm after Trojan heroes; Charops, a Lycian fighting on the Trojan side, fits the L\(_5\) naming convention, and catalogs list it in the L\(_5\) camp.<sup>[4](https://academic.oup.com/mnras/article/504/2/1571/6207955)</sup> Objects with similar orbital characteristics include 1583 Antilochus, 1749 Telamon, and 2893 Peiroos.<sup>[1](https://www.spacereference.org/asteroid/16070-charops-1999-rb101)</sup>

## References

1. [Asteroid Charops (16070), Space Reference](https://www.spacereference.org/asteroid/16070-charops-1999-rb101)
2. [SBDB Filter Parameters, JPL Solar System Dynamics](https://ssd-api.jpl.nasa.gov/doc/sbdb_filter.html)
3. [North Greek Affiliations of Trojan Names, Journal of Hellenic Studies (via Zenodo)](https://zenodo.org/records/2518303/files/article.pdf)
4. [Astrocladistics of the Jovian Trojan Swarms, Monthly Notices of the Royal Astronomical Society 504, 1571 (2021)](https://academic.oup.com/mnras/article/504/2/1571/6207955)
5. [Asteroids IV chapter: Trojan asteroid albedos and diameters (Morbidelli et al.)](https://www-n.oca.eu/morby/papers/Rev39.pdf)
6. [Comparison of the physical properties of the L4 and L5 Trojan asteroids from ATLAS data, arXiv:2101.04602](https://arxiv.org/abs/2101.04602)

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*Topic: Encyclopedia › Places and geography › Extraterrestrial places › Small bodies of the Solar System › Main-belt asteroids and numbered minor planets*

*Initially written Oct 21, 2026 · Edited: Oct 25, 2026*

*Copyright 2026 EdgeChat AI, a subsidiary of Biostate AI.*

License: Edgepedia Community License 1.0, https://www.edgepedia.org/edgepedia/license