The comet C/2024 S1 (ATLAS)nicknamed “Halloween comet” due to the possibility that it could become visible in our skies in the next few days, it disintegrated on 28 October 2024 as it approached a short distance from the Sun. Discovered very recently, on 27 September 2024 at a distance of 27 million km from the Sun, the comet had made itself talked about as a possible “heir” of the so-called “comet of the century” after the latter’s passage near the Earth in the first half of October, but unfortunately C/2024 S2 did not survive its passage to perihelion, the point of its orbit closest to the Sun, scheduled for October 28th. Had it survived, C/2024 S1 might have earned the nickname “Halloween comet” becoming as bright as the star Siriusthe brightest in the sky. Unfortunately, however, this will not happen.
The first signs of a fragmentation of the celestial body – which is believed to come from the Oort cloud, a vast spherical distribution of minor bodies in the outermost part of the Solar System – date back to the first days of October, but on October 28th the space telescope SOHO (Solar and Heliospheric Observatory) for observing the Sun he captured with his coronagraph LASCO (Large Angle and Spectrometric Coronagraph Experiment) the comet as it “extinguished” as it made its close passage with our star. In the lower part of the video at the head of this article you can observe the comet appearing, approaching the Sun and suddenly “disappearing”: that is the moment in which the comet essentially stopped existing, transforming into a mass of debris.
The disintegration of a comet when it passes close to the Sun is far from uncommon: after all, our star emits a large amount of energy and comets are largely composed of frozen volatile substances. But complete fragmentation was even more probable in a case like that of C/2024 S1, given its very small distance to perihelion: we are talking about just 1.2 million kmwhich may seem like a lot to us but it’s a very close distance to pass by a star! For comparison, the Earth is about 150 million km from the Sun and the perihelion of the “comet of the century” C/2023 A3 was over 58 million km distance, comparable with the distance between the Sun and the planet Mercury.
It is no coincidence that C/2024 S1 had such a close perihelion. The comet is in fact part of the so-called Kreutz sungrazersa family of comets believed to be actually fragments of a much larger comet that fragmented in 371 BC after having passed very close to the Sun. These comet-fragments today orbit in a time ranging from approximately 500 years to 800 years. The Kreutz sungrazers they are also called “grazing comets” or more journalistically “suicide comets” precisely because of the very short distance with which they touch the Sun.
