# 15913 Telemachus

**15913 Telemachus** (provisional designation 1997 TZ27) is a Jupiter Trojan asteroid, a small body that shares Jupiter's orbit while librating (oscillating back and forth around a stable point) around one of the planet's stable [Lagrange points](https://www.edgepedia.org/lagrange-points). It was discovered on 1 October 1997 by the Uppsala-DLR Trojan Survey at the [La Silla Observatory](https://www.edgepedia.org/la-silla-observatory), and it belongs to the Greek camp at Jupiter's leading L4 point.<sup>[1](https://www.spacereference.org/asteroid/15913-telemachus-1997-tz27)</sup> It is named for [Telemachus](https://www.edgepedia.org/telemachus), the son of Odysseus in Greek mythology.

| Key fact | Detail |
|---|---|
| Designation | 15913 Telemachus; provisional designation 1997 TZ27<sup>[1](https://www.spacereference.org/asteroid/15913-telemachus-1997-tz27)</sup> |
| Discovery | 1 October 1997, Uppsala-DLR Trojan Survey, La Silla<sup>[9](https://asteroidname.com/asteroid/telemachus)</sup> |
| Orbit class | Jupiter Trojan (TJN), Greek camp at the leading L4 point<sup>[2](https://ssd-api.jpl.nasa.gov/doc/sbdb_filter.html)</sup> |
| Semimajor axis | 5.192 au<sup>[10](https://minorplanetcenter.net/db_search/show_object?object_id=15913)</sup> |
| Mean orbital speed | 13.08 km/s<sup>[1](https://www.spacereference.org/asteroid/15913-telemachus-1997-tz27)</sup> |

## Discovery

The asteroid was found on 1 October 1997 by the Uppsala-DLR Trojan Survey, a collaboration that used the [European Southern Observatory](https://www.edgepedia.org/european-southern-observatory)'s La Silla site in Chile to search for bodies in Jupiter's Trojan swarms.<sup>[10](https://minorplanetcenter.net/db_search/show_object?object_id=15913)</sup> On receiving a number, the object received the permanent designation 15913 and the name Telemachus; its provisional designation from the discovery apparition was 1997 TZ27.<sup>[1](https://www.spacereference.org/asteroid/15913-telemachus-1997-tz27)</sup>

## Orbit and dynamical state

Its mean orbital speed is 13.08 km/s, and its orbit passes no closer than 3.89 AU to [Earth's orbit](https://www.edgepedia.org/earths-orbit) at their closest points.<sup>[1](https://www.spacereference.org/asteroid/15913-telemachus-1997-tz27)</sup>

**Greek camp membership.** Telemachus is listed among the Greek-camp Trojans, the swarm that travels 60° ahead of Jupiter at the L4 Lagrange point.<sup>[3](https://www.nasa.gov/missions/how-were-the-trojan-asteroids-discovered-and-named/)</sup> Bodies in this resonance stay fixed relative to Jupiter as both orbit the Sun, held in place where the combined gravity of Jupiter and the Sun creates a stable holding region.<sup>[4](https://www.jpl.nasa.gov/news/cosmic-detective-work-why-we-care-about-space-rocks/)</sup>

## Name

The asteroid takes its name from Telemachus (Τηλέμαχος), the son of Odysseus in Homer's *Odyssey*.<sup>[5](https://www.behindthename.com/name/telemachus)</sup> The Greek name is a Latinized form of Telemachos, derived from a word meaning "fighting from afar", built on τῆλε (*tele*, "afar, far off") and μάχη (*mache*, "battle").<sup>[5](https://www.behindthename.com/name/telemachus)</sup>

The name follows the naming convention for Jupiter's Trojans. Astronomers named these asteroids after heroes of the [Trojan War](https://www.edgepedia.org/trojan-war) and eventually settled on a division in which Jupiter's L4 asteroids receive Greek characters and the L5 asteroids receive Trojan characters, making L4 and L5 the "Greek camp" and the "Trojan camp".<sup>[3](https://www.nasa.gov/missions/how-were-the-trojan-asteroids-discovered-and-named/)</sup> As an Odyssey figure on the Greek side, Telemachus fits the Greek-camp tradition.<sup>[5](https://www.behindthename.com/name/telemachus)</sup>

## Physical properties

Like the rest of the population, it orbits far from Earth, which is one reason the Trojans remain less well characterized physically than the main asteroid belt.<sup>[6](https://academic.oup.com/mnras/article/499/3/3630/5918394)</sup>

## A small member of a captured population

Telemachus's orbit records where the Trojans as a population came from. The swarms librate around Jupiter's stable L4 and L5 Lagrange points, 60° ahead of and behind the planet, and their inclinations cover a fairly uniform range from 0° to 35° with a median of 10°; at 7.2°, Telemachus sits below that median.<sup>[7](https://link.springer.com/article/10.1007/s11214-023-01031-4)</sup> The Trojans' spectral and physical properties resemble those of small bodies in the outer solar system, such as irregular satellites and [Kuiper belt](https://www.edgepedia.org/kuiper-belt) objects, and the leading view is that they were captured from the primordial Kuiper belt during the giant planet instability rather than forming near Jupiter.<sup>[7](https://link.springer.com/article/10.1007/s11214-023-01031-4)</sup> Because most Trojans tens of kilometers across or larger are on stable orbits, bodies of Telemachus's size are presumed survivors of whatever process filled the swarms.<sup>[7](https://link.springer.com/article/10.1007/s11214-023-01031-4)</sup>

No spacecraft has visited Telemachus. NASA's Lucy mission, launched on October 16, 2021, is the first mission to the Trojans, flying by several members of both swarms over a 12-year journey, but its targets are other, larger members of the population.<sup>[8](https://science.nasa.gov/solar-system/planets/jupiter/nasas-lucy-mission-a-journey-to-the-young-solar-system/)</sup>

## References

1. [Asteroid 15913 Telemachus (1997 TZ27), Space Reference](https://www.spacereference.org/asteroid/15913-telemachus-1997-tz27)
2. [SBDB (filter): Available SBDB Orbit Classes, JPL Solar System Dynamics](https://ssd-api.jpl.nasa.gov/doc/sbdb_filter.html)
3. [How Were the Trojan Asteroids Discovered and Named?, NASA](https://www.nasa.gov/missions/how-were-the-trojan-asteroids-discovered-and-named/)
4. [Cosmic Detective Work: Why We Care About Space Rocks, NASA Jet Propulsion Laboratory](https://www.jpl.nasa.gov/news/cosmic-detective-work-why-we-care-about-space-rocks/)
5. [Meaning, origin and history of the name Telemachus, Behind the Name](https://www.behindthename.com/name/telemachus)
6. [Pair of Jovian Trojans at the L4 Lagrange point, Monthly Notices of the Royal Astronomical Society](https://academic.oup.com/mnras/article/499/3/3630/5918394)
7. [Bottke, W. F. and colleagues (2023). Origin and Evolution of Jupiter's Trojan Asteroids. Space Science Reviews 219, 83.](https://link.springer.com/article/10.1007/s11214-023-01031-4)
8. [NASA's Lucy Mission: A Journey to the Young Solar System, NASA Science](https://science.nasa.gov/solar-system/planets/jupiter/nasas-lucy-mission-a-journey-to-the-young-solar-system/)
9. [(15913) Telemachus – asteroid discovered 1997 | AsteroidName](https://asteroidname.com/asteroid/telemachus)
10. [IAU Minor Planet Center, minorplanetcenter.net](https://minorplanetcenter.net/db_search/show_object?object_id=15913)

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*Topic: Encyclopedia › Places and geography › Extraterrestrial places › Small bodies of the Solar System › Jupiter Trojans and other dynamical groups › Greek-camp Jupiter Trojans › Heroes of the Odyssean circle*

*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
