A swarm of space rocks is heading our way with more than a dozen asteroids due to zoom past Earth this week, Nasa has revealed.
The largest of these is roughly the size of the Great Pyramid of Giza, whilst the smallest is a maximum of 16 metres in size – making it a few metres longer than a double-decker bus.
According to predictions issued by Nasa's Centre for Near-Earth Studies, the first seven space rocks will zoom past today.
They are called 2019 TU, 2019 TW1, 2019 RK, 2019 TC1, 2019 SB6, 2019 TM and 2019 TS.
The largest of today's cosmic visitors – 2019 TM – is believed to be up to 63 metres in size.
If it hit Earth, it would probably cause local damage and a limited number of deaths, but certainly wouldn't endanger humanity.
On Wednesday, October 9, rocks called 2019 TV1, 2019 TZ and 2019 SL7 will zoom by.
The big boy of the bunch – the pyramid sized 2019 SX5 – is the only object to come close to our planet on Thursday.
Then 2019 TN1, 2019 SK8, 2019 SV9 and 2019 SE2 will zip past Earth in the early hours of Saturday, October 12, before 019 TH2 and 2019 TT1 cap off a remarkable week on Sunday.
Of course, all of the asteroids will miss Earth, with 2019 SL7 predicted to make the closest pass and come within 337,000 miles of Earth.
Space rock aficionados will have to wait a decade for a real close encounter with an asteroid.
In a piece of cosmic irony, a monster asteroid named after Apophis, an Egyptian God of Chaos, will fly past on Friday, April 13, 2029.
It is due to travel so close to Earth that billions of people will be able to see it with the naked eye.
The 340-metre wide behemoth is on a path which brings the rock within such a short distance of our planet's surface that Nasa once feared it was going to hit us.
Luckily, subsequent calculations showed the object was going to miss us and pass within just 19,000 miles of our planet's surface – a hair's breadth in cosmic terms.
If Apophis did hit a city like London, it would wipe out millions of people and create a crater roughly three miles wide, but our species would probably survive.
It's only when space rocks are half a mile wide or larger that they start to pose an existential threat to humanity because larger objects could throw so much dust and debris into the air that sunlight is blocked so plants across the planet can no longer grow.
The asteroid was discussed at Nasa's annual Planetary Defence Conference earlier this year, where scientists and disaster planners also simulated an asteroid apocalypse in order to practice their emergency response.
'Apophis is a representative of about 2,000 currently known Potentially Hazardous Asteroids (PHAs)," said Paul Chodas, director of Nasa's Centre for Near Earth Objects Studies (CNEOS).
'By observing Apophis during its 2029 flyby, we will gain important scientific knowledge that could one day be used for planetary defence.'
Nasa's guide to viewing Apophis
'On April 13, 2029, a speck of light will streak across the sky getting brighter and faster. At one point it will travel more than the width of the full Moon within a minute and it will get as bright as the stars in the Little Dipper. But it won't be a satellite or an airplane—it will be a 340-meter-wide near-Earth asteroid called 99942 Apophis that will cruise harmlessly by Earth, about 19,000 miles (31,000 km) above the surface. That's within the distance that some of our spacecraft that orbit Earth.
'It's rare for an asteroid of this size to pass by the Earth so close. Although scientists have spotted small asteroids, on the order of 5-10 meters, flying by Earth at a similar distance, asteroids the size of Apophis are far fewer in number and so do not pass this close to Earth as often.
'The asteroid, looking like a moving star-like point of light, will first become visible to the naked eye in the night sky over the southern hemisphere, flying above Earth from the east coast to the west coast of Australia. It will be mid-morning on the East Coast of the United States when Apophis is above Australia. It will then cross the Indian Ocean, and by the afternoon in the eastern US it will have crossed the equator, still moving west, above Africa. At closest approach, just before 6 p.m. EDT, Apophis will be over the Atlantic Ocean – and it will move so fast that it will cross the Atlantic in just an hour. By 7 p.m. EDT, the asteroid will have crossed over the United States.'
In 2013, Nasa calculated that Apophis would not hit Earth.
'We have effectively ruled out the possibility of an Earth impact by Apophis in 2036,' said Don Yeomans, manager of NASA's Near-Earth Object Program Office at JPL.
'The impact odds as they stand now are less than one in a million, which makes us comfortable saying we can effectively rule out an Earth impact in 2036. Our interest in asteroid Apophis will essentially be for its scientific interest for the foreseeable future.'
However, it said the 'April 13, 2029, flyby of asteroid Apophis will be one for the record books' because of how close the object will come to our planet.
'The Apophis close approach in 2029 will be an incredible opportunity for science,' said Marina Brozović, a radar scientist at Nasa's Jet Propulsion Laboratory in Pasadena, California.
\'We'll observe the asteroid with both optical and radar telescopes. With radar observations, we might be able to see surface details that are only a few meters in size.'
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