The “once-in-a-lifetime” comet that recently lit up night skies for the first time in millennia might be falling apart after being singed as it slingshotted around the sun, new photos suggest. However, it is too early to tell for sure.
Comet C/2024 G3 (ATLAS) made its closest approach to Earth on Jan. 14 and reached its minimum distance from the sun, known as perihelion, a day later. As a result, it shone as bright as Venus for several days and was visible across the globe. It has now begun its long journey back to the Oort Cloud — a reservoir of comets and other icy objects near the edge of the solar system — and is not expected to return for around 160,000 years.
Although the comet has now become too faint for people to see with the naked eye, astrophotographers have continued to snap images of the comet as it journeys back to the outer solar system — and things aren’t looking good for the icy object.
Hungarian astrophotographer Lionel Majzik photographed the comet from the dark skies of Chile over three consecutive nights, between Jan. 18 and Jan. 20. He noticed that the comet’s coma — the cloud around its nucleus — had dimmed significantly during this time, hinting that the comet’s head may have started breaking apart, according to Spaceweather.com.
The photos also showed a bright streak of light, or “streamer,” in the comet’s tail, which is a sign that large amounts of gas and dust are leaking out of the comet, potentially via new cracks in its nucleus.
“Only one week ago, Comet ATLAS passed very close to the sun,” Spaceweather.com reported. “The thermal stress may have been too much.”
Related: ‘Totally amazing’ astronaut photo captures comet C/2024 G3 ATLAS shooting past Earth from the ISS
The latest development is surprising, considering that initial observations of the comet after perihelion suggested it had remained unaffected by its “near-death encounter with the Sun,” Richard Miles, an astronomer and comet expert with the British Astronomical Association, said in a statement. However, it can be “quite difficult to predict how the comet will behave” after such an encounter, he added.
Simulations from Nicolas Lefaudeux, a French engineer and amateur astronomer, suggested that the comet’s coma might lose brightness between Jan. 19 and Jan. 26 “while the comet’s head remains hidden in the sun’s glare,” Spaceweather.com previously reported. Although this could have caused the dimming in the new images, it does not explain the streamer in the comet’s tail.
Therefore, more observations will be required in the coming weeks to accurately determine the comet’s fate.
Comet disintegration
Comets like C/2024 G3 disintegrate when high levels of solar radiation crack open their nuclei and cause severe outgassing. This slowly destabilizes the object and causes it to break apart into fragments that are loosely bound together by gravity. Eventually, these fragments separate and are scattered across the comet’s orbital pathway.
For example, in October 2024, the “Halloween comet” C/2024 S1 (ATLAS) was seen disintegrating as it made its closest approach to the sun.
The last super-bright comet to visit Earth — comet C/2023 A3 (Tsuchinshan-ATLAS) — also showed signs of disintegrating en route to its perihelion in October last year. When these signs were first spotted, researchers noted that the comet’s fragmentation may have begun 80,000 years earlier, during its previous solar slingshot.
Therefore, C/2024 G3 might just be wounded by its recent close approach and may stay intact for the next 160,000 years.
