Comet Atlas had been forecast to become "really, really stunning" within weeks, as it got closer to Earth.
Astronomers expected that it could be seen moving among the stars before reaching its closest point to us, in May.
They spoke hopefully of spotting its greenish hue as it blazed through the solar system, though noted that much was still mysterious about the object, which was first spotted in May.
Now, however, the object appears to have broken up and will not make for such a beautiful – or even visible – sight once it actually arrives.
Astronomers tracking the journey of the comet, which is officially known as C/2019 Y4 (ATLAS), show that it appears to have broken up.
Recent images show that there appears to be an "elongated pseudo-nucleus" that is lined up with the tail. That shape is in line with "a major disruption" of the comet, astronomers Quanzhi Ye and Qicheng Zhang wrote in a message to colleagues.
Those observations were confirmed in follow-up observations taken over the first week of April, confirming the shape and the indication that it seems to have broken apart.
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The Atlas Comet is still relatively new to astronomers, and so little is still known about it and how it could have broken up. As such, it could still be visible from Earth – either as a whole object or broken into pieces – but scientists are unlikely to know for sure until it gets closer to Earth.
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