Asteroid
2016 TD passed by the Earth at a distance of 226 200 km (0.59 times
the average distance between the Earth and the Moon, 0.15% of
the average distance between the Earth and the Sun), at about 5.15 pm GMT on Friday 30 September 2016. There
was no
danger
of the asteroid
hitting us, though had it done so it would have presented no
threat. 2016 TD has an estimated equivalent diameter of 4-14
m (i.e.
it is estimated that a spherical object with the same volume would be 4-14 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 43 and 28 km above the ground, with only fragmentary
material reaching the Earth's surface.
The calculated orbit of 2016 TD. Minor Planet Center.
2016 TD was discovered on 1 October 2016 (the day after its closest approach to the Earth) by the University of Arizona's Catalina Sky Survey,
which is located in the Catalina Mountains north of Tucson. The
designation 2016 TD implies that it was the fourth asteroid (asteroid D)
discovered in the first half of October 2016 (period 2016 D).
2016 TD has a 759 day orbital period and an elliptical orbit tilted at
an angle of 13.0° to the plain of the Solar System
that
takes it from 0.85 AU from the Sun (i.e. 85% of the average distance at
which the Earth orbits the Sun)
to 2.40 AU from the Sun (i.e. 240% of
the average distance at which the Earth orbits the Sun, considerably
more than the distance at which the planet Mars orbits the Sun).
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 very common, with the
last thought to have happened in June 2014 and the next predicted in October 2018. 2016 TD also has occasional close encounters with the planet Mars, with the next predicted for April 2108.
See also...
Fireball over the Eastern Great Lakes region. The American Meteor Society has
received reports of a bright fireball meteor being seen over parts of
the Eastern Great Lakes region slightly after 10.35 pm on Tuesday 4
October 2016 Eastern Daylight Time (slightly after 2.35 am on Wednesday 5... 
Fireball over Cyprus. The Cyprus Astronomical Society has reported a bright fireball meteor
over the island at about 1.00 am local time on Friday 9 September 2016.
The meteor is described as having a faint blue...
Asteroid 2016 RO17 passes the Earth. Asteroid
2016 RO17 passed by the Earth at a distance of 882 200 km (2.30 times
the average distance between the Earth and the Moon, 0.6% of
the average distance between the Earth and the Sun), slightly before 2.30 am GMT on Thursday 8...
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