(98943) Torifune
Asteroid· orbits the Sun
(98943) Torifune is a small near-Earth asteroid about 840 m long. JAXA's Hayabusa2 flew past it on 5 July 2026 at 5.3 km/s, 744 m from its centre and about 400 m from its surface, and found two lobes in contact.
Open in 3D viewSee (98943) Torifune in the live, interactive 3D map
Key facts
Radius
0.27 km
Distance from Sun
1.03 AU
Orbital period
383.0 days
Eccentricity
0.2192
Rotation
5.02 hours
Science
Physical
- Mean radius
- 0.27 km
- Rotation period
- 5.02 hours
Orbital
- Semi-major axis
- 1.03 AU
- From catalogued orbital elements (MPC)
- Eccentricity
- 0.2192
- From catalogued orbital elements (MPC)
- Inclination
- 4.81 °
- From catalogued orbital elements (MPC)
- Orbital period
- 383.0 days
- From catalogued orbital elements (MPC)
- Perihelion
- 0.806 AU
- Computed from the orbital elements
- Aphelion
- 1.26 AU
- Computed from the orbital elements
- Mean orbital velocity
- 29.3 km/s
- Computed from the orbital elements
Discovery
- Discovered
- February 3, 2001
- Discoverer
- LINEAR (Socorro)
Composition
- Make-up
- A contact binary about 840 × 340 m, with an average diameter of about 540 m (JAXA; the figures may change as the shape model is refined). Its spectrum was first classed as L-type (Binzel et al. 2004); later work favours the S complex (Hirabayashi et al. 2026). It turns in about 5.02 hours, from light curves. No shape model has been published yet, so it is drawn as a plain sphere of its average size. Its mass has not been measured.
Radiation & temperature
- Insolation
- 0.939 S⊕ · 94% of the sunlight Earth receives
- Computed from the distance to the Sun (inverse-square; Earth's sunlight = 1), before any atmosphere.
- Geometric albedo
- 0.22
- Geometric albedo about 0.22 (Fornasier et al. 2024).
- Equilibrium temperature
- 257 K (-16 °C)
- Computed from albedo + distance from the Sun (airless black body); uses the geometric albedo as an estimate
Discovery & history
- Discovered
- February 3, 2001
- By
- LINEAR (Socorro)
- Name
- Torifune, short for Ame-no-torifune, is a god in Japanese mythology, and also the name of the god's ship, which can travel safely at high speed like a bird and steady as a rock. The name expresses the hope that Hayabusa2 would carry out its high-speed flyby safely.
Found by LINEAR at Socorro, New Mexico, on 3 February 2001, and catalogued as 2001 CC21. On 5 July 2026 Hayabusa2, on its extended mission after returning samples of Ryugu, passed it at 5.3 km/s, 744 m from its centre and about 400 m from its surface (JAXA).
Passed at 5.3 km/s, 744 m from its centre and about 400 m from its surface (JAXA), and found two lobes in contact.
Images
No openly licensed image of Torifune has been found. Hayabusa2 photographed it when it flew past on 5 July 2026, but JAXA's images are not openly licensed.