Asteroid 2022 CJ5 passed by the Earth at a distance of about 31 400 km (0.08 times the average distance between the Earth and the Moon, or 0.02% of the distance between the Earth and the Sun, and about 4400 km closer to the Earth than satellites in geostationary orbits, but 77 times the distance at which the International Space Station obits), slightly after 10.50 am GMT on Thursday 10 February 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 CE has an estimated equivalent diameter of 3-5 m (i.e. it is estimated that a spherical object with the same volume would be 3-5 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 40 above the ground, with only fragmentary material reaching the Earth's surface.
2022 CJ5 was discovered on 9 February 2022 (the day before its closest approach to the Earth) by the University of Arizona's Mt. Lemmon Survey at the Steward Observatory on Mount Lemmon in the Catalina Mountains north of Tucson. The designation 2022 CJ5 implies that the asteroid was the 134th object (asteroid J5 - in numbering asteroids the letters A-Z, 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 J5 = (25 x 5) + 9 = 134) discovered in the first half of February 2022 (period 2022 - the year being split into 24 half-months represented by the letters A-Y, with I being excluded).
2022 CJ5 has a 877 day (2.40 year) orbital period, with an elliptical orbit tilted at an angle of 5.86° 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 2.68 AU (268% of the distance at which the Earth orbits the Sun, and considerably outside the orbit of the planet Mars). 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 2022 CJ5 has occasional close encounters with the Earth, with the last thought to have happened in February 2010 and the next predicted in July this year.
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