TRENDING
Some observations are the result of years of meticulous planning and cooperation between astronomers, different telescopes and observatories, and even different governments.
Others are more serendipitous, and are little more than happy accidents.
That's the case with the Hubble's recent observation of Comet C/2025 K1 (ATLAS) as it fragmented. The observations are the work of a team of researchers focused on comets.
The group obtained some Hubble observing time with a proposal to observe a completely different comet.
Those plans didn't work out because of technical restraints, so they scrambled to find a different target.
They selected C/2025 K1 (ATLAS), and it happened to break apart while they observed it. The comet, also known simply as Comet K1, is non-periodic and came directly from the Oort Cloud, a reservoir of billions of icy objects in the Solar System's distant reaches.
Objects from the Oort Cloud are made of primordial material from the Solar System's early days.
But when they approach the inner Solar System, they're subject to heating by the Sun and their surfaces are altered.
They've also been hit by cosmic rays. This creates a scientific conundrum.
It's difficult to tell which of their properties are pristine and which have been altered.
Scientists would love to see inside one, to observe ancient unaltered material.
Studying their tails and coma can provide some insights, just as NASA's Stardust mission did when it returned a sample from Comet Wild 2 in 2006, the first sample of a comet ever obtained.
But watching as a comet breaks apart is another opening.
That's exactly what happened with the Hubble's observations of Comet K1. "Because the interior of a comet is rarely exposed, fragmentation events provide valuable opportunities to probe subsurface structure, volatile reservoirs, and short-timescale activation processes," explain the authors of new research. The results of the Hubble's observations are presented in new research in the journal Icarus.
It's titled "Sequential fragmentation of C/2025 K1 (ATLAS) after its near-sun passage," and the lead author is Dennis Bodewits.
Bodewits is a professor in Auburn University’s Department of Physics. "Comet C/2025 K1 (ATLAS) reached perihelion at 0.33 au on 2025 October 8.
Daily monitoring by the LCO Outbursting Objects Key Project revealed a major activity increase between November 2 and 4, accompanied by rapid changes in coma morphology," the authors write.
LCO stands for the Las Cumbres Observatory, and the Project is a network of observatories trying to undertstand the frequency and the nature of outbursts on small bodies in the Solar System. "Serendipitous HST/STIS acquisition images obtained on November 8–10 captured the comet only days after this event and resolved five fragments, providing an early high-resolution view of a nucleus in the process of disruption," the researchers explain. “Sometimes the best science happens by accident,” said co-author John Noonan, also a professor in the Department of Physics at Auburn University.