Space rock would be disasterous if it hit, but will skirt Earth’s gravitational pull
A threatening asteroid which last passed Earth in 1975 is making its comeback this Halloween. The asteroid, nicknamed “The Great Pumpkin,” is estimated to have a diameter of 400 m and an incoming velocity of over 120,000 km/h. NASA considers the asteroid to be potentially hazardous, as it will pass close enough to Earth to be significantly influenced by the planet’s gravity.
“One unusual thing about this one is it’s pretty big … but wasn’t found until two weeks before it was going to pass by Earth,” said Catherine Lovekin, an assistant professor of physics and astronomy at Mount Allison. “It is sort of unusual to pass by something that big until that soon before it hits us.”
According to NASA, the asteroid will not collide with the Earth or exert any gravitational pull on its plates or tides. Were it to strike, the asteroid could create a localised catastrophe but would not be large enough to imperil the whole planet.
Lovekin said a crater measuring up to 30 km across could form if the asteroid hit Earth.
Asteroids much smaller than “The Great Pumpkin” can cause havoc when they collide with our planet. On Feb. 15, 2013, an 18-m meteorite crashed near Chelyabinsk, Russia at a speed of almost 70,000 km/h. The meteorite exploded, sending shockwaves which injured more than 1,000 people.
Lovekin said the asteroid would look like a faint star from the ground as it passes Earth, and should be visible with smaller telescopes. As the asteroid makes its approach, NASA will use radar imaging to examine its surface details to determine its mass and density. The asteroid can be viewed live on the Virtual Telescope Project website at 2:05 p.m. EDT.
NASA estimates that another asteroid of this size won’t pass this close to Earth until 2027. The asteroid was discovered through the Pan-STARRS telescope at the University of Hawaii.
“[Asteroids] are hard to predict. A lot of them are very small, so there are large-scale campaigns to monitor the sky to look for asteroids, to try and find them before they become dangerous to us,” said Lovekin. “We [had] this monitoring campaign [at the Mount Allison Gemini Observatory] to try to find the near-Earth ones just this summer.”
Scientists have been developing ways to destroy or deflect asteroids should they pass too close to Earth. One proposal is to use spacecraft or nuclear weapons to deflect asteroids in a different direction.
