There is good news and bad news. The good news is that scientists have discovered a new comet that appears incredibly bright. It could even appear brighter than some of the stars seen in the night sky.
Now for the bad news, which isn’t bad. You’ll need to wait until October 2024 to see Comet/2023 A3 or Tsuchinshan-ATLAS, as it’s also known.
You won’t want to miss C/2023 A3 when that date rolls around. First of all, it should appear extremely bright. Secondly, astronomers calculate it takes 80,000 years for C/2023 A3 to orbit the sun.
All About C/2023 A3
Comets, which are roughly the “size of a small town,” can be thought of as giant snowballs made of frozen gasses with embedded rock and dust particles, NASA explains.
As a comet nears the sun, it warms up and its ice begins to change from a solid to gas. This produces what’s known as a “coma,” which is the fuzzy-shaped cloud surrounding the ball of ice. The coma, by the way, can be thousands of miles in diameter.
Then, radiation pressure — or solar wind — “blows” the expanding coma out to form the long tail that gives comets their distinctive shape.
Interestingly, astronomers divide months in half — days 1 to 15 and days 16 to month’s end — in what’s known as “half months” to name newly discovered solar system bodies, such as comets and asteroids. These half months are then labeled as the successive letters of the alphabet. Early January, for instance, is “A.”
Since the comet was the third object discovered in the first half-month of 2023, it received the designation Comet 2023 A3, or C/2023 A3.
The comet was first picked up by the Asteroid Terrestrial-impact Last Alert System (ATLAS) telescope in South Africa on February 22, 2023, according to EarthSky. Importantly, astronomers at Purple Mountain Observatory in China found the comet independently on images taken January 9, 2023.
Since Purple Mountain in Mandarin is “Tsuchinshan,” C/2023 A3 is also called Tsuchinshan-ATLAS.
C/2023 A3’s Approach To Earth
C/2023 A3 is traveling at approximately 180,610 miles per hour, or about 50 miles per second, relative to Earth. Right now, the comet is calculated to be between the orbits of Saturn and Jupiter.
Astronomers calculate that C/2023 A3 will make its closest approach to the sun — known as perihelion — on September 28, 2024. Then the comet should be at its closest to Earth on October 13, 2024, EarthSky explains.
How To See C/2023 A3
As previously unknown comets enter the inner solar system, they could fragment and fall apart as they are warmed by the sun. Then again, they could appear even brighter as their ice reflects the sunlight.
If the comet remains intact, it may become visible with amateur telescopes sometime in June 2024.
At perihelion, when C/2023 A3 is closest to the sun, it will be low on the eastern horizon and may not be visible to many people.
Then, in early October, as the comet nears Earth, it should be visible low in the sky at dawn, EarthSky explains. In late October, however, C/2023 A3 should appear shining brightly high in the evening sky.
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