A sungrazing comet that was around 30 meters across plunged into the Sun at the same time that a “halo”, a CME where the front edge of expands in all directions around the sun like a halo, coronal mass ejection (CME) which made it look like the comet had a devastating impact.
In all reality the CME originated from the far side of the Sun and didn’t have any interaction with the comet at all. There’s no direct correlation between the comet impact and the CME that exploded immediately after.
Sungrazing comets are comets that zoom past the sun, in its atmosphere and never actually hit the Sun. Sungrazing comets are not a new thing, they actually happen a lot and have been observed for many hundreds of years.
According to the US Navy, “A popular misconception is that sungrazing comets cause solar flares and CMEs (coronal mass ejections). While it is true that we have observed bright comets approach the Sun immediately before CME’s/flares, there is absolutely no connection between the two events. The sungrazer comets — in fact all comets — are completely insignificant in size compared the Sun. Even the brightest Kreutz comets observed by LASCO are believed to be no more than tens of meters in diameter (compared to the diameter of the Sun, which is roughly 1,390,000,000 meters!).”
Sungrazing comets have been observed as far back as the year -371, Brian Marsden has speculated that a comet seen by Aristotle and Ephorus may be a Kreutz sungrazer.