Friday 14 January 2022

Asteroid 2022 AY5 passes the Earth.

Asteroid 2022 AY5 passed by the Earth at a distance of about 101 700 km (0.27 times the average distance between the Earth and the Moon, or 0.07% of the distance between the Earth and the Sun), at about 10.35 am GMT on Monday 10 January 2022. There was no danger of the asteroid hitting us, though were it to do so it would not have presented a significant threat. 2022 AY5 has an estimated equivalent diameter of 3-9 m (i.e. it is estimated that a spherical object with the same volume would be 3-9 m in diameter), and an object of this size would be expected to explode in an airburst (an explosion caused by superheating from friction with the Earth's atmosphere, which is greater than that caused by simply falling, due to the orbital momentum of the asteroid) more than 33 km above the ground, with only fragmentary material reaching the Earth's surface.

The relative positions of 2022 AY5 and the Earth on at midnight GMT on 23 December 2021. JPL Small Body Database.

2022 AY5 was discovered on 11 January 2022 (the day after its closest approach to the Earth) by the University of Arizona's Catalina Sky Survey, which is located in the Catalina Mountains north of Tucson. The designation 2022 AY5 implies that it was the 149th asteroid (object Y5 - in numbering asteroids the letters A-Y, excluding I, are assigned numbers from 1 to 25, with a number added to the end each time the alphabet is ended so that A = 1, A1 = 26, A2 = 51, etc., which means that Y5 implies the 149th asteroid (G5 = (25 x 5) + 24 = 149) discovered in the first half of December 2022 (period 2022 A - the year being split into 24 half-months represented by the letters A-Y, with I being excluded).

The orbit and current position of 2022 AY5. The Sky Live 3D Solar System Simulator.

2022 AY5 has a 721 day (1.97 year) orbital period, with an elliptical orbit tilted at an angle of 0.83° to the plain of the Solar System which takes in to 0.90 AU from the Sun (90% of the distance at which the Earth orbits the Sun) and out to 2.25 AU (225% of the distance at which the Earth orbits the Sun, and more than the distance at which the planet Mars orbits the Sun). It is therefore classed as an Apollo Group Asteroid (an asteroid that is on average further from the Sun than the Earth, but which does get closer). This means that Asteroid 2022 AY5 has occasional close encounters with the Earth, with the most recent having happened in September 2021, and the next predicted for November 2023. The asteroid also has occasional close encounters with the planet Mars, with the last thought to have happened in July 2003, and the next predicted in June 2037.

See also...

Follow Sciency Thoughts on Facebook.

Follow Sciency Thoughts on Twitter.