Key facts
- Discovered by
- LINEAR
- Discovery site
- Lincoln Lab's ETS
- Discovery date
- 26 September 1998
- Pronunciation
- / ˌ iː t oʊ ˈ k ɑː w ə / , Japanese: [ itoꜜkawa ]
- Named after
- Hideo Itokawa
- Alternative designations
- 1998 SF 36
- Minor planet category
- Apollo NEO PHA
- Observation arc
- 20.38 yr (7,443 d)
- Aphelion
- 1.6951 AU
- Perihelion
- 0.9532 AU
- Semi major axis
- 1.3241 AU
- Orbital period sidereal
- 1.52 yr (557 d)
- Mean anomaly
- 288.88 °
- Mean motion
- 0° 38 48.48 / day
- Inclination
- 1.6214°
- Longitude of ascending node
- 69.081°
- Argument of perihelion
- 162.82°
- Earth moid
- 0.0131 AU (5.10 LD )
via Wikipedia infobox
Wikidata facts
- Instance of
- near-Earth asteroid
- Named after
- Hideo Itokawa
- Followed by
- (25144) 1998 SC43
- Follows
- 25142 Hopf
- Parent body
- Sun
- Minor-planet group
- Apollo asteroid
- Diameter
- 0.33
- Orbital period
- 556.5406776413872
- Image
- Itokawa06 hayabusa.jpg
Show 21 more facts
- provisional designation
- 1998 SF36
- discoverer or inventor
- Lincoln Near-Earth Asteroid Research
- time of discovery or invention
- 1998-09-26
- orbital inclination
- 1.620938690165939
- Commons gallery
- 25143 Itokawa
- albedo
- 0.53
- orbital eccentricity
- 0.2801500981413037
- periapsis
- 0.9531785784123709
- apoapsis
- 1.695091778925195
- semi-major axis of an orbit
- 1.324135178668783
- mean anomaly
- 41.26158479412086
- longitude of ascending node
- 69.07562356929041
- argument of periapsis
- 162.853569017811
- absolute magnitude
- 19.26
- surface gravity
- 0.0001
- density
- 1.9
- rotation period
- 12.132
- asteroid spectral type
- S-type asteroid
- Commons category
- 25143 Itokawa
- time of periapsis
- 2460936.71180455
- epoch
- November 21, 2025
via Wikidata · CC0
~11 min read
Encyclopedic overview
25143 Itokawa (provisional designation 1998 SF36) is a sub-kilometer near-Earth object of the Apollo group and also a potentially hazardous asteroid. It was discovered by the LINEAR program in 1998 and later named after Japanese rocket engineer Hideo Itokawa. The peanut-shaped S-type asteroid has a rotation period of 12.1 hours and measures approximately 330 meters (1,100 feet) in diameter. Due to its low density and high porosity, Itokawa is considered to be a rubble pile, consisting of numerous boulders of different sizes rather than of a single solid body.
It was the first asteroid to be the target of a sample-return mission, of the Japanese space probe Hayabusa, which collected more than 1500 regolith dust particles from the asteroid's surface in 2005. Since its return to Earth in 2010, the mineralogy, petrography, chemistry, and isotope ratios of these particles have been studied in detail, providing insights into the evolution of the Solar System. Itokawa was the smallest asteroid to be photographed and visited by a spacecraft prior to the DART mission to Dimorphos in 2022.
Excerpted from Wikipedia’s “25143 Itokawa” article, available under the CC BY-SA 4.0 licence.
On the map
17 mapped locations