An asteroid flew closer to Earth than the Moon — but nobody knew till two days later

• A 100-metre wide asteroid flew closer to Earth than the Moon in June and nobody knew until two days later.
  
• July’s European Space Agency’s (ESA) Near-Earth Object (NEO) Coordination Centre newsletter highlights that the asteroid was was only 0.8 lunar distance (LD) from the planet.
  
• Dubbed 2020 LD, the asteroid is the biggest to have come under 1 LD not just in 2020, but since 2011.
  

Asteroids come and go, but we normally know when they’ll be flying past the planet. However, last month on June 5, an asteroid flew closer to Earth than even the Moon and astronomers didn’t detect it until two days later.

Not only was it the biggest asteroid to have come within one lunar distance of Earth in 2020 — but biggest to have gotten this close since 2011.

The asteroid dubbed 2020 LD is nearly 100 metres in diameter — bigger than India’s Taj Mahal.

According to the European Space Agency’s (ESA) Near-Earth Object (NEO) Coordination Centre, it just 0.8 lunar distances away when it made its close approach on June 5.

That means if the Moon is 384,317 kilometres from Earth, the asteroid was 307,454 kilometres from the planet when it flew by.

Asteroids to fly past Earth within 1 LD in 2020:

Asteroid	Date of Approach	Lunar Distance (LD) from Earth	Diameter (m)
2020 LD	June 5	0.80	89 - 200
2020 KC5	May 29	0.97	9.1 - 20
2020 KJ4	May 28	0.37	2.8 - 6.2
2020 KF5	May 28	0.64	3.5 - 7.8
2020 JN	May 5	0.65	9 - 20

So far, this year, there have 45 asteroids to fly past the Earth undetected, but 2020 LD was by far the largest. In fact, it’s the 9th largest asteroid ever to fly past the Earth in documented history.

If it would have hit Earth, it may not have annihilated the entire planet, but it definitely would have meant devastation for a city-sized area. The 2013 Chelyabinsk incident in Russia was caused by a mere 20-metre asteroid and it destroyed 500 square kilometres as it exploded with a force of 40 Hiroshima nuclear bombs.

2020 LD would have been capable of causing five times the amount of damage — assuming that like the Chelyabinsk asteroid — it exploded before actually hitting the ground. Otherwise, the outcome could have been even worse, akin to the Tunguska event where 2,000 square kilometres of forest were flattened.

SEE ALSO:
The 10 biggest asteroids that pose a threat to Earth in 2020

Asteroid Day — everything you need to know about the rocks in our solar system that could one day hit Earth

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