Now that’s scary: 400-metre-wide asteroid to zoom 'close' by Earth on Halloween

A large asteroid discovered only weeks ago will tear past the Earth on Halloween, Nasa has announced, estimating that it will come closer than any object of its size in the next 20 years.

The asteroid, nicknamed “the Great Pumpkin” and “Spooky” but technically known as TB145, is an estimated 400metres wide - 20 times bigger than the meteorite that screamed across the Russian sky and exploded over Chelyabinsk in 2013, shattering windows with shock waves and debris that injured more than a thousand people .

The Chelyabinsk object entered the atmosphere at about 19km per second. TB145 will fly past at around 35km per second , about 483,000km from Earth, slightly farther than the moon.

Scientists at Nasa’s Centre for Near-Earth Object Studies discovered TB145 on October 10 and announced it to the public this week. The asteroid will make its closest approach on October 31 at about 5.05pm GMT. Nasa estimates that no similar object will make a comparable approach until 2027.

TB145 has an unusually oblong orbit, in an area searched less often than the flat-disc plane on which the solar system is arranged. TB145 slices through that plane at a 40-degree angle. Now it’s been spotted, the center’s Paul Chodas said its trajectory was “well understood”.