Halloween asteroid to just miss Earth at a rather scary speed

21 Oct 2015

This Halloween — on 31 October — an asteroid is expected to fly just past Earth at a ‘scary’ speed in one of Earth’s closest encounters with an asteroid for a decade.

The Halloween asteroid – dubbed 2015 TB145 – was spotted only two weeks ago by the Pan-STARRS telescope based in Hawaii and has been described as having ‘an extremely eccentric and high-inclination orbit’.

Not only that, but NASA has said it believes that the asteroid flyby will come within 500,000km of Earth, or the equivalent of nearly the distance between Earth at the moon, or 1.3 lunar distance.

While it will pass by without incident, the asteroid will be by no means a small object, with an expected diameter of 1,542ft or, according to the Huffington Post, will be 28-times the size of the Chelyabinsk meteor that burnt up over Siberia in 2013, leading to a number of injuries.

It is also a case of a close shave as NASA has described its velocity of 35km/s as “unusually high”.

‘A truly outstanding scientific opportunity’

According to the document released by NASA, this will be the closest approach of any space object to Earth until August 2027 when the asteroid 1999 AN10 will come within one lunar distance of Earth.

Back in July 2006, the object 2004 XP14 did come closer to Earth, just skimming past Earth at 1.1 lunar distances.

Astronomers are very interested, however, in this spooky Halloween flyby as NASA has said it intends to snap some photographs of it with a range resolution as high as 2Mp in what is being described as “a truly outstanding scientific opportunity to study the physical properties of this object”.

Sadly, the asteroid will not be visible to the naked eye, but keen astronomers in the northern hemisphere with powerful enough telescopes should be able to spot it that morning, but its proximity to the waning gibbous moon could make basic telescopes unable to see it.

At its closest approach at 4.14pm Irish time, it will be too close to the sun to be observable by telescopes.

Near-miss asteroid image via Shutterstock

Colm Gorey was a senior journalist with Silicon Republic