Subaru Telescope archive reveals rare images of naked Comet 28P/Neujmin

Astronomers have discovered rare, unobstructed images of Comet 28P/Neujmin within the archival data of the Subaru Telescope in Hawaii. The comet was unintentionally captured in 2016 during observations intended for other scientific targets.

Because the comet was positioned more than 10 astronomical units from the Sun at the time of the images, it was far enough from solar heat to prevent the release of volatiles. This resulted in a “naked” comet, meaning it lacked the typical glowing shroud of gas and dust known as a coma that usually obscures the nucleus. This rare state allowed researchers to study the solid nucleus of the 21 km-wide comet directly.

The discovery was made by a team of Japanese scientists, led by Takafumi Ootsubo from the Chiba Institute of Technology, while searching through the National Astronomical Observatory of Japan’s extensive image archives. The findings were published in the Publications of the Astronomical Society of Japan.