| Minorplanet: | yes |
| 17365 Thymbraeus | |
| Background: |
|
| Discovered: | 7 November 1978 |
| Mpc Name: | (17365) Thymbraeus |
| Mp Category: | Jupiter trojan Trojan |
| Orbit Ref: |   |
| Epoch: | 13 September 2023 (JD 2460200.5) |
| Uncertainty: | 0 |
| Observation Arc: | 68.79 yr (25,125 days) |
| Earliest Precovery Date: | 23 November 1954 |
| Perihelion: | 4.856 AU |
| Semimajor: | 5.270 AU |
| Eccentricity: | 0.0785 |
| Period: | 12.10 yr (4,418 days) |
| Mean Motion: | / day |
| Inclination: | 11.644° |
| Asc Node: | 252.124° |
| Arg Peri: | 117.711° |
| Rotation: | (retrograde) or (prograde) |
| Right Asc North Pole: | (retrograde) or (prograde) |
| Declination: | (retrograde) or + (prograde) |
17365 Thymbraeus (provisional designation ) is a Jupiter trojan from the Trojan camp, which is located in Jupiter's trailing Lagrangian point.
It was discovered by Eleanor Helin and Schelte Bus at Palomar Observatory on 7 November 1978. Thymbraeus is 45km (28miles) in diameter and has an elongated dumbbell shape that is on the verge of splitting apart due to centrifugal forces of its rapid rotation. The asteroid's density is less than that of water, indicating that it has a highly porous interior structure similar to a rubble pile. It was given the name Thymbraeus on 27 February 2023, after one of the two sons of the Trojan priest Laocoön who was attacked by sea serpents for attempting to warn the Trojans about the Trojan horse in Greek mythology.