The comet C/2023 A3 (Tsuchinshan-ATLAS) was discovered in 2023 and is on its way into the inner solar system. Early estimates say it may outshine the brightest stars in the night sky. The comet is said to be traveling at about 180,000 mph. Initially, it was reported that it would return in 80,000 years, but NASA revised its calculations and says it might never return.
NASA said it’s highly unlikely Tsuchinshan-ATLAS will be visible in daylight hours, except perhaps at twilight. In the past 300 years of astronomical observation, only nine previous comets have been bright enough to spot during the day. The last were Comet West in 1976 and, under ideal conditions, Comet Hale-Bopp in 1997. Binoculars or telescopes would be helpful to see it in the night sky later in the month.
Discovery and naming
Comet C/2023 A3 (Tsuchinshan-ATLAS) was discovered on Jan. 9, 2023 at a distance of around 8 astronomical units at the Purple Mountain Observatory in China. One astronomical unit (abbreviated to 1 AU) corresponds to the average distance between the Earth and the sun and is equivalent to approximately 93 million miles. On Feb. 22, 2023, the Asteroid Terrestrial-impact Last Alert System (ATLAS) in South Africa was able to prove that it was not an asteroid, as initially assumed, but a comet. The name of the comet is made up of the alternative name Zijinshan Astronomical Observatory for the Purple Mountain Observatory and the abbreviation ATLAS.
The comet is about 2 miles in diameter, accompanied by a tail stretching out for some tens of millions of miles.
Comets are frozen leftovers from the formation of the solar system composed of dust, rock and ice. They range from a few miles to tens of miles wide, but as they orbit closer to the sun, they heat up and spew gases and dust into a glowing head that can be larger than a planet. This material forms a tail that stretches millions of miles.
Tail it like it is
As dust and gases stream away from the nucleus, sunlight and particles coming from the sun push them into a bright tail that stretches behind the comet for millions of miles.
When astronomers look closely, they find that comets actually have two separate tails. One looks white and is made of dust. This dust tail traces a broad, gently curving path behind the comet. The other tail is bluish and is made up of electrically charged gas molecules, or ions. The ion tail always points directly away from the sun.
Sources: NASA, Cal-Tech, Space.com, Haus der Astrnomie, Farmers Almanac
