|Discovery date 28 May 1998|
Discovered 28 May 1998
Mean anomaly 287.54278°
Discovery site Arizona
|Minor planet category Apollo|
Discoverer Tom Gehrels
Asteroid group Apollo asteroid
|Discovered by Spacewatch, Tom Gehrels|
Aphelion 1.4816757 AU (221.65553 Gm)
Perihelion 0.98408102 AU (147.216425 Gm)
Semi-major axis 1.23287838 AU (184.435980 Gm)
Similar Solar System, 6489 Golevka, 4769 Castalia, 4660 Nereus, (53319) 1999 JM8
Asteroide 1998 ky26
1998 KY26 (also written 1998 KY26) is a small near-Earth asteroid. It was discovered on June 2, 1998, by Spacewatch and observed until June 8, when it passed 800,000 kilometers (half a million miles) away from Earth (a little more than twice the Earth–Moon distance). It is roughly spherical and is only about 30 metres (98 ft) in diameter.
With a Rotation period of 10.7 minutes it has one of the shortest sidereal days of any known object in the Solar System, and cannot possibly be a rubble pile. It is also one of the most easily accessible objects in the Solar System, and its orbit frequently brings it on a path very similar to the optimum Earth–Mars transfer orbit. This, coupled with the fact that it is water rich, makes it an attractive target for further study and a potential source of water for future missions to Mars.
Asteroid 1998 KY26 is the smallest solar system object ever studied in detail and, with a rotational period of 10.7 minutes, was the fastest-spinning object observed at the time of its discovery: most asteroids with established rotational rates have periods measured in hours. It was the first recognized minor object that spins so fast that it must be a monolithic object rather than a rubble pile, as many asteroids are thought to be. Since 1998 KY26 was found to be a fast rotator, several other small asteroids have been found to also have short rotation periods, some even faster than 1998 KY26.
Optical and radar observations indicate that 1998 KY26 is a water-rich object.
These physical properties were measured by an international team of astronomers led by Dr. Steven J. Ostro of the Jet Propulsion Laboratory. The team used a radar telescope in California and optical telescopes in the Czech Republic, Hawaii, Arizona and California.