NASA volunteer makes a puzzling white dwarf discovery

NASA has announced that a volunteer working with the Backyard Worlds: Planet 9 project has made a very impressive discovery. The amateur scientist has discovered what is said to be the oldest and coldest known white dwarf. A white dwarf is the remnant of a dead star said to be about the size of Earth.

One of the puzzling aspects of this white dwarf is that it is the first known with multiple dust rings surrounding it. The official name for the star is LSPM J0207+3331, but it goes by J0207 for short. The discovery is forcing scientists to rethink models of planetary systems and might help us learn more about the distant future of our solar system.

The process that feeds material into the rings around the white dwarf is thought to work on billion-year timescales. That massive timescale challenges the models currently in use for white dwarfs that only work well up to about 100 million years. The white dwarf is about 145 light-years away from Earth in the Capricornus constellation.

These star remnants slowly cool as they age and the scientists on the project estimate that J0207 is about 3 billion years old. The age is based on its temperature of a bit over 10,500 degrees Fahrenheit. Strong infrared signals received by NASA's WISE spacecraft suggested the presence of dust making this white dwarf the oldest and coldest known with dust rings to date.

NASA says that before this discovery, dust disks had only been found surrounding white dwarf stars about 1/3 J0207's age. The amateur scientist who discovered J0207 is a German called Melina Thévenot. She thought initially that the infrared signal was bad data, but using WISE data realized that the signal was too bright and too far away to be a brown dwarf star. She then passed the data on to the Backyard Worlds: Planet 9 team for more observation.