An airplane-sized asteroid came within 1/4 the moon's distance to Earth on July 13, 2023. However, scientists didn't detect the asteroid until two days later.
The post Airplane-sized asteroid found 2 days after brush by Earth first appeared on EarthSky.
Newly-discovered #asteroid 2023 NT1 passed about 1/4 the Moon's distance on July 13, but wasn't discovered until July 15, as it approached Earth in the daytime sky. It may be as large as 60 meters across, possibly larger than the asteroid that caused Meteor Crater in Arizona. pic.twitter.com/VLXB4ChTMJ
— Tony Dunn (@tony873004) July 16, 2023
On July 15, 2023, the ATLAS (Asteroid Terrestrial-impact Last Alert System) observatory in South Africa discovered an asteroid up to 200 feet (60 m) in size two days after it passed closest to Earth. NASA calls an asteroid of this size airplane-sized. Compare 2023 NT1 to the asteroid that hit Arizona some 50,000 years ago, leaving the large, famous Barringer Crater: That destructive asteroid may have been just a bit smaller, at about 160 feet (50 m) in size. The newly discovered asteroid, named 2023 NT1, passed within only 1/4 the distance to the moon. 2023 NT1 came closest to Earth on July 13, 2023, at 10:12 UTC.
Fortunately for us, it was not a threat to Earth. Why didn’t one of our observatories pick it up sooner? Because the asteroid came at us from the direction of the sun. This is a known weak spot in our defense against space rocks. But the European Space Agency (ESA) has a plan for that.
ESA has a planned mission called NEOMIR that will detect asteroids coming from the sun’s direction. The NEOMIR mission will orbit between Earth and the sun at the first Lagrange point (L1). It’ll act as an early warning system for asteroids – 65 feet (20 m) and larger – that instruments on Earth’s surface cannot see. The downside is that the launch of NEOMIR is not until 2030.
Another notable asteroid that headed toward Earth from the sun’s direction was the Chelyabinsk meteor. This asteroid broke up in the atmosphere on February 15, 2013, over Russia. Scientists estimate it was 65 feet (20 m) in size. It exploded in the atmosphere and created a shockwave that damaged thousands of buildings, breaking windows and injuring roughly 1,500 people from flying shards of glass. Moreover, it was the largest asteroid to strike Earth in over a century.
Asteroids passing close to Earth is nothing new. Fortunately, most of those asteroids are quite small or pass many times the moon’s distance from Earth, or both.
Just last month, house-sized and bus-sized asteroids passed inside the moon’s orbit just one day apart. Within the past year, some small asteroids have dropped bits of meteorites onto Earth. One little (3 m) space rock sprayed meteorites over France in February. Another dropped meteorites in Canada in November 2022.
Bottom line: An airplane-sized asteroid came within 1/4 the moon’s distance to Earth on July 13, 2023. However, scientists didn’t detect the asteroid until two days after its closest approach.
The post Airplane-sized asteroid found 2 days after brush by Earth first appeared on EarthSky.
