A massive object similar in composition to the famous Halley’s Comet has been seen by a team of scientists using the ESA/NASA Hubble Space Telescope being ripped apart and scattered in the atmosphere of a white dwarf star located in a binary system roughly 170 light-years from Earth in the constellation Boötes.
Many white dwarfs are known to be polluted with infalling debris from rocky, asteroid-like objects. However, this is the first time an icy comet-like object has been seen polluting a white dwarf’s atmosphere.
While its make-up is similar to Halley’s Comet, scientists say the object is actually 100,000 times larger and has a much higher amount of water. What’s more, the scientists suggest that the object is also rich in the elements essential for life, including nitrogen, carbon, oxygen, and sulfur.
“Nitrogen is a very important element for life as we know it,” explains team leader Siyi Xu of the European Southern Observatory in Garching, Germany. “This particular object is quite rich in nitrogen, more so than any object observed in our solar system.”
Discovery of the object also provides evidence for a belt of comet-like bodies orbiting the white dwarf, similar to our solar system’s Kuiper Belt, which extends outward from Neptune’s orbit.
The Kuiper Belt is home to many dwarf planets, comets, and other small bodies left over from the Solar System’s formation. Experts believe comets from the Kuiper Belt may have been responsible for delivering water and the basic building blocks of life to Earth billions of years ago.
Now, scientists suggest the icy bodies around the white dwarf may have also been around to witness the star’s evolution from a bloated red giant star into the small, dense white dwarf we see today. What’s more, the team suggests there may potentially be unseen planets orbiting the star that disturbed the belt, drawing the icy objects closer into the white dwarf.
It is also possible that a companion star — separated by 2,000 times the distance that the Earth is from the sun — may have disturbed the belt, causing objects from the belt to travel toward the burned-out star.
Results of this research are published online in PDF format. The W. M. Keck Observatory was also used during the study.
NOTE: Halley last appeared in the inner parts of the Solar System in 1986 and will next appear in mid-2061.
Top Image – Artist’s impression showing a massive, comet-like object falling towards a white dwarf star. Credit: NASA, ESA, and Z. Levy (STScI)