A massive asteroid is set to skim the Earth on December 16, just over a week before Christmas.
With a diameter of about 3 miles, the asteroid – named 3200 Phaethon after the Greek demi-god who, according to legend, nearly set the Earth on fire – is classified as “potentially hazardous” by the Minor Planet Center.
Unlike its namesake, however, 3200 Phaethon is unlikely to destroy our planet.
It will pass within 6.5 million miles of the Earth, which is relatively close in space terms, but still around 27 times the distance of the moon.
Scientists at NASA’s Jet Propulsion Laboratory are planning to use the opportunity to obtain a detailed 3D model of the asteroid, which has a particularly irregular shape.
What is 3200 Phaethon?
First detected in December 2007, 3200 Phaethon is widely thought to be the parent body for the Geminid meteor shower, which this year is due to peak on the night of December 13.
This would make the Geminids one of only two major meteor showers not originating from a comet – the other being the Quadrantids in January.
The main difference between asteroids and comets is their composition. Asteroids are made up of metals and rocky material, while comets are made up of ice, dust and rocky material.
Comets which approach the Sun lose material with each orbit, because some of their ice melts and vaporises to form a tail.
Although 3200 Phaethon appears asteroidal most of the time, it occasionally shows low levels of activity when it approaches the sun, leading some astronomers to suggest it’s an inactive comet nucleus.
As the asteroid’s approach next month will be the closest to Earth since 1974 – and until after 2093 – scientists will be watching closely to try to detect the “skirts” seen in radar observations of active comet nuclei.
Will you be able to see it?
According to NASA, 3200 Phaethon will be visible in small telescopes for experienced observers in areas with dark skies.
It is potentially detectable for three weeks, but will be at its brightest between December 11 and 21.
If you don’t see the asteroid itself, be sure to look out for the Geminid meteor shower, which is set to provide a spectacular show over the course of 10 nights in December, with as many as 100 shooting stars every hour.