3200 Phaethon

Also known as 1983 TB, Phaethon

Apollo asteroid notable for its very small perihelion and for being the progenitor of the Geminid meteor shower

Key facts

Discovered by: Simon Green John K. Davies / IRAS
Discovery date: October 11, 1983
Pronunciation: / ˈ f eɪ . ə θ ɒ n /
Named after: Phaëthon
Alternative designations: 1983 TB
Minor planet category: Apollo asteroid Potentially hazardous asteroid Mercury-crosser asteroid Venus-crosser asteroid Earth-crosser asteroid Mars-crosser asteroid
Adjectives: Phaethonian / f eɪ ə ˈ θ oʊ n i ə n /
Observation arc: 12,941 days (35.43 yr)
Aphelion: 2.4028 AU (359 million km )
Perihelion: 0.13998 AU (20.9 million km)
Semi major axis: 1.2714 AU (190 million km)
Orbital period sidereal: 523.6 days (1.434 yr)
Average orbital speed: 19.9 km/s (45,000 mph)
Mean anomaly: 313.94°
Mean motion: 0° 41 15.108 / day
Inclination: 22.260°
Longitude of ascending node: 265.22°
Time of perihelion: May 15, 2022

via Wikipedia infobox

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Encyclopedic overview

3200 Phaethon (/ˈfeɪ.əˌθɒn/; previously sometimes spelled Phæton), provisionally designated 1983 TB, is an active Apollo asteroid with an orbit that brings it closer to the Sun than any other named asteroid (though there are numerous unnamed asteroids with smaller perihelia, such as (137924) 2000 BD19). For this reason, it was named after the Greek Hero, Phaëthon, son of the sun god Helios. It is 5.8 km (3.6 mi) in diameter and is the parent body of the Geminids meteor shower of mid-December. With an observation arc of 35+ years, it has a very well determined orbit. The 2017 Earth approach distance of about 10 million km was known with an accuracy of ±700 m.

Discovery

Excerpted from Wikipedia’s “3200 Phaethon” article, available under the CC BY-SA 4.0 licence.