Asteroid 2006 UF17 passed by the Earth at a distance of about 18 027 000
km (46.9 times the average distance between the Earth and the Moon, or 12.0% of the distance between the Earth and the Sun), slightly after 0.30 am
GMT on Friday 30 March 2018. There was no danger of
the asteroid hitting us, though were it to do so it would have
presented a significant threat. 2006 UF17 has an estimated
equivalent
diameter of 90-280 m (i.e. it is estimated that a spherical object
with
the same volume would be 90-280 m in diameter), and an object at the upper end of this range would be predicted to be capable of
passing through the Earth's
atmosphere relatively intact, impacting the ground directly with an
explosion that would be about 60 000 times as powerful as the
Hiroshima
bomb. Such an impact would result in an impact crater overt 4 km
in
diameter
and devastation on a global scale, as well as climatic effects that
would last years or even decades.
The calculated orbit of 2006 UF17 Minor Planet Center.
2006 UF17 was discovered on 19 October 2006 by the University of Arizona's Catalina Sky Survey,
which is located in the Catalina Mountains north of Tucson. The
designation 2006 UF17 implies that it was the 431st asteroid (asteroid F17)
discovered in the second half of October 2006 (period 2006 U)
2006 UF17 has a 1424 day orbital period and an eccentric orbit
tilted at an angle of 3.73° to the plane of the Solar System, which
takes it from 0.37 AU from the Sun (i.e. 37% of he average distance at
which the Earth orbits the Sun, slightly less the distance at which the
planet Mercury orbits the Sun) to 4.49 AU from the Sun (i.e. 4.49% of the
average distance at which the Earth orbits the Sun, and almost three times as distant from the Sun than the planet Mars). It is therefore
classed as an
Apollo Group Asteroid (an asteroid that is on average further from the
Sun than the Earth, but which does get closer). This means that close
encounters between the asteroid and Earth are extremely common, with the
last having occurred in October 2006 and the next predicted
in November 2041. As an asteroid probably larger than 150 m in diameter
that occasionally comes within 0.05 AU of the Earth, 2006 UF17 is also
classified as a Potentially Hazardous Asteroid.
2006 UF17 also
has frequent close encounters with the planets Mercury, which it is
thought to have last passed in June 2014, and is next predicted to
pass in November 2027, and Venus, which it last came close to in June 2010
and
is next predicted to pass in March 2022). Asteroids
which make close passes to multiple planets are considered to be in
unstable orbits, and are often eventually knocked out of these orbits by
these encounters, either being knocked onto a new, more stable orbit,
dropped into the Sun, knocked out of the Solar System or occasionally
colliding with a planet.
See also...
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