Discovery and Origin of Comet C/2023 A3 (Tsuchinshan-ATLAS)
The comet was first spotted by the Purple Mountain Observatory in China on January 9, 2023, and independently discovered by ATLAS South Africa on February 22, 2023. C/2023 A3 (Tsuchinshan-ATLAS) originates from the Oort cloud, a region in the outer reaches of our solar system.
Orbit and Orbital Characteristics
C/2023 A3 (Tsuchinshan-ATLAS) follows a highly elliptical orbit, characteristic of long-period comets from the Oort cloud. It reached its perihelion at a distance of 0.39 AU (58 million km; 36 million mi) from the Sun on September 27, 2024. The comet’s closest approach to Earth occurred on October 12, 2024.
Notable Appearances and Observations
C/2023 A3 (Tsuchinshan-ATLAS) has been hailed as the brightest comet in the last 13 years, surpassing the famous C/2020 F3 (NEOWISE) from summer 2020. It developed a stunning tail approximately 21° long, about 42 times the size of the Full Moon’s disk. The comet was visible to the naked eye from the Northern Hemisphere starting around October 11, 2024, with its peak brightness occurring shortly after passing the Sun on October 9, reaching a magnitude of -4.9.
Scientific Significance and Composition
Spectroscopic analysis of C/2023 A3 (Tsuchinshan-ATLAS) on May 31, 2024, when it was 2.33 AU from the Sun, revealed strong cyanide emission and indicated that the comet is carbon-depleted. The comet also exhibited a large dust-to-gas ratio, which contributed to its impressive visual appearance. As with many comets, C/2023 A3 (Tsuchinshan-ATLAS) is composed of a mixture of ice, dust, and rocky material, often described as a “dirty snowball”.
