The idea of an asteroid slamming into Earth has long been the preserve of science fiction. However Earth’s pockmarked surface are an enduring testament that direct – and sometimes calamitous – asteroid collisions really do happen. The most famous asteroid ever is the one that smashed into our planet 65 million years ago, resulting in the eventual death of the dinosaurs.
US space agency NASA believes it has identified more than 90 percent of those asteroids capable of causing an event like the dinosaurs’ extinction – more than half a mile wide or larger.
2019 OK is probably the largest asteroid to pass this close to Earth in quite a number of years
However, this leaves 10 percent of asteroids that we know nothing about.
Now, following last week’s surprise discovery of asteroid 2019 OK’s near miss, it is an opportune time to examine the most deadly asteroids about to make near-Earth impacts.
According to data from NASA, 2019 OK was large – an estimated 187 to 427 ft (57 to 130) wide – and hurtling fast along a path bringing it within only 45,000 miles (73,000km) of Earth.
This was less than one-fifth of the distance to the Moon and what the Royal Institution of Australia’s Professor Alan Duffy described as “uncomfortably close.”
Asteroid near miss 2019: Asteroids potentially pose a continual existential threat to life on Earth
Professor Michael Brown, of Monash University’s School of Physics and Astronomy admitted: “It snuck up on us pretty quickly.
“People are only sort of realising what happened pretty much after it has already flung past us.”
The asteroid’s presence was discovered only hours before it flew past Earth
Professor Brown added: “It shook me out my morning complacency.
“It is probably the largest asteroid to pass this close to Earth in quite a number of years.”
READ MORE: Mars Insight lander detects first MARSQUAKE
The biggest asteroids and near misses set to pass Earth this year:
Date Name Diameter (m) Impact probability
August 19 2015 ME131 270–860 1/710,000,000
October 3 2007 FT3 210–680 1/11,000,000
November 23 2017 RZ17 180–590 1/290,000,000
December 28 2010 GD37 1000–3100 1/400,000,000
December 28 2015 HV182 92–300 1/450,000,000
How much damage can an asteroid inflict?
An asteroid falling from deep space can possess an unbelievable amount of energy.
In 2028, the asteroid 1997XF11 will come uncomfortably close to the planet but will thankfully miss Earth.
A mile-wide asteroid travelling at 30,000mph (48280.32 kph) has the energy equal to a 1 million megaton bomb.
This asteroid would have the energy 10 million times greater than the bomb that fell on Hiroshima.
The quantity of dust and debris thrown into the atmosphere would block out sunlight and cause most living things on the planet to perish.
And if such an asteroid landed in the ocean, it would cause massive tidal waves hundreds of feet high, completely scrub the coastlines in the vicinity.
It is highly likely such an asteroid would wipe out most of the life on the planet.