Astronomers have discovered that the near-Earth asteroid 1998 SH2, previously thought to be a typical asteroid, is actually a 'dark comet' exhibiting hidden cometary activity.

This finding challenges traditional classifications of space objects, as dark comets can appear as asteroids but show non-gravitational movements caused by sublimating ice beneath their surfaces.

The study, published in Nature Astronomy, reveals that 1998 SH2's unexpected orbital behavior was confirmed through observations using advanced telescopes like ATLAS and CFHT.

Researchers note that such objects may have contributed to delivering water to early Earth and could explain anomalies like the interstellar object 'Oumuamua.

The discovery underscores the importance of re-evaluating astrometry data to identify mislabeled comets, which could impact planetary defense strategies by altering risk assessments for potential Earth impacts.

While 1998 SH2 poses no immediate threat, its existence highlights the need for continuous monitoring of near-Earth objects, as their unpredictable movements complicate efforts to predict trajectories and compositions.