2008 HJ is a sub-kilometer
asteroid, classified as
near-Earth object
A near-Earth object (NEO) is any small Solar System body whose orbit brings it into proximity with Earth. By convention, a Solar System body is a NEO if its closest approach to the Sun (perihelion) is less than 1.3 astronomical units (AU). ...
of the
Apollo group.
It was discovered by
Lincoln Laboratory ETS, New Mexico. Observers M. Bezpalko, D. Torres, R. Kracke, G. Spitz, J. Kistler. Richard Miles using the
Faulkes Telescope South
The Faulkes Telescope South is a clone of the Liverpool Telescope and is located at Siding Spring Observatory in New South Wales, Australia. It is a Ritchey-Chrétien telescope. It was designed to be operated remotely with the aim of encourag ...
at
Siding Spring Observatory,
Australia determined that the asteroid rotates rapidly. It measures only 12 m by 24 m and is very dense, having a mass of about 5,000
tonne
The tonne ( or ; symbol: t) is a unit of mass equal to 1000 kilograms. It is a non-SI unit accepted for use with SI. It is also referred to as a metric ton to distinguish it from the non-metric units of the short ton ( United State ...
s. If the asteroid were not dense, it is probable that the rapid rotation would cause the asteroid to disrupt and fly apart.
At the time of discovery, had the smallest known
rotation period in the
Solar System
The Solar System Capitalization of the name varies. The International Astronomical Union, the authoritative body regarding astronomical nomenclature, specifies capitalizing the names of all individual astronomical objects but uses mixed "Solar ...
, completing one revolution every 42.7 seconds.
[
It is listed on the ]Sentry Risk Table
Sentry is a highly automated impact prediction system operated by the JPL Center for NEO Studies (CNEOS) since 2002. It continually monitors the most up-to-date asteroid catalog for possibilities of future impact with Earth over the next 100+ y ...
with a 1 in 17,000 chance of impacting Earth on May 2, 2081.[ An impact from this object would be comparable to the Chelyabinsk meteor.
]
See also
*List of fast rotators (minor planets)
This is a list of fast rotators—"minor planets" (which includes asteroids) that have an List of exceptional asteroids, exceptionally short rotation period, also called "rotation rate" or "spin rate". In some cases the rotation period is n ...
References
External links
MPEC 2008-H26 : 2008 HJ
(Discovery)
*
*
*
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Minor planet object articles (unnumbered)
Potential impact events caused by near-Earth objects
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20080424
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