Asteroid
2015 TR238 passed by the Earth at a distance of 18 510 000 km (48.2
times the average distance between the Earth and the Moon, or 12.4% of
the average distance between the Earth and the Sun), slightly after 8.55 am on Friday 30 October 2015. There was no danger of the asteroid
hitting us, though had it done so it would have presented only a minor
threat. 2015 TR238 has an estimated equivalent diameter of 17-54 m (i.e.
it is estimated that a spherical object with the same volume would be
17-54 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 between 27 and 8 km above the ground, with only fragmentary
material reaching the Earth's surface.
The calculated orbit of 2015 TR238. JPL Small Body Database.
2015 TR238 was discovered on 15 October 2015 (fifteen days after 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
2015 TR238 implies that the asteroid was the 5968th object (object R238) discovered in the first half of October 2015 (period 2015 T).
2015
TR238 has an 1381 day orbital period and an eccentric orbit tilted at
an angle of 3.22° to the plane of the Solar System that takes it from
1.12 AU from the Sun (i.e. 112 % of the average distance at which the
Earth orbits the Sun) to 3.74 AU from the Sun (i.e. 374% of the average
distance at which the Earth orbits the Sun, considerably over twice the
distance at which the planet Mars orbits). It is therefore classed as an
Amor Group Asteroid (an asteroid which comes close to the Earth, but
which is always outside the Earth's orbit).
See also...
Asteroid 2015 TF passes the Earth. Asteroid
2015 TF passed by the Earth at a distance of 11 550 000 km (30.0 times
the average distance between the Earth and the Moon, or 7.72% of the
average distance between the Earth and the Sun), slightly after 4.45 am
GMT on Tuesday 27...
Fireball over northern Europe.
Eyewitnesses
across much of northern Europe reported seeing a bright fireball in the
sky moving southwest to northeast at about 6.05 pm GMT on Saturday 31
October 2015. The event was seen from the Netherlands, Germany, Denmark,
southern...
Asteroid
1998 XN2 passed by the Earth at a distance of 11 610 000 km (30.2 times
the average distance between the Earth and the Moon, or 7.76% of the
average distance between the Earth and the Sun), slightly before 2.55 pm
GMT on Sunday 25 October...