Asteroid 2017 QB35 passed by the Earth at a distance of about 356 800
km (0.93 times the average distance between the Earth and the Moon, or
0.24% of the distance between the Earth and the Sun), slightly after 1.40 am
GMT on Sunday 3 September 2017. There was no danger of
the asteroid hitting us, though were it to do so it would not have
presented a significant threat. 2017 QB35 has an estimated
equivalent
diameter of 2-8 m (i.e. it is estimated that a spherical object
with
the same volume would be 2-8 m in diameter), and an object of this
size would be expected to explode in
an airburst (an explosion caused by superheating from friction with the
Earth's atmosphere, which is greater than that caused by simply
falling, due to the orbital momentum of the asteroid) in the atmosphere more than 35 km above the ground, with only fragmentary material
reaching the Earth's surface.
The calculated orbit of 2017 QB35 Minor Planet Center.
2017 QB35 was discovered on 31 August 2017 (three days before its closest approach to the Earth) by the
University of Arizona's Mt. Lemmon Survey at the Steward Observatory on Mount
Lemmon in the Catalina Mountains north of Tucson. The designation 2017 QB35
implies that the asteroid was the 877th object (object B35) discovered in the second half of August 2017 (period 2017 Q).
2017 QB35 has a 327 day orbital period, with an elliptical orbit tilted at
an angle of 5.33° to the plain of the Solar System which takes in to
0.80 AU from the Sun (480% of the distance at which the Earth orbits the
Sun) and out to
1.06 AU (6%
further away from the Sun than the Earth). This means that close
encounters between the asteroid and Earth are fairly common, with the
last thought to have happened in March this year and the next predicted
in June 2025. It also has close encounters with the planet Venus, with the next expected in January 2027. Although it does cross the Earth's
orbit and is briefly
further from the Sun on each cycle, 2017 QB35 spends most of its time
closer to the Sun than we are, and is therefore classified as an Aten
Group Asteroid.
See also...
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