For the first time, an asteroid being torn apart by a dead star has been captured on an image. The encounter has resulted in the asteroid being destroyed, forming a glowing ring of dust particles and debris similar to Saturn’s disk.
An image of the asteroid being ripped apart as it came too close to the white dwarf called SDSS SDSS1228+1040
was captured by a multinational group of astronomers using ESO’s Very Large Telescope (VLT).
The gas produced by collisions among the debris inside the ring is illuminated by ultraviolet rays from the star, which causes it to emit a dark red glow that the researchers observed and turned into the image of the ring, according to a University of Warwick press release.
While the glowing ring is similar to Saturn’s rings, Christopher Manser of the University of Warwick’s Astrophysics Group and who led the study explains that the scale of the white dwarf and its debris is many times greater in size.
“The diameter of the gap inside of the debris ring is 700,000 kilometers, approximately half the size of the Sun, and the same space could fit both Saturn and its rings, which are only around 270,000 km across. At the same time, the white dwarf is seven times smaller than Saturn, but weighs 2500 times more.”
Debris rings have been found surrounding a few other white dwarfs, but this image gives scientists an unprecedented insight into the structure of these systems.
“We knew about these debris disks around white dwarfs for over twenty years, but have only now been able to obtain the first image of one of these disks,” Manser said.
Researchers used Doppler tomography to acquire the image, much the same as a Computed Tomography (CT) is used in hospitals. Both systems take scans from different angles and then processed using computer software, which turns it into an image.
In a CT scan, the machine moves around the patient, but in the researchers case, the disk is rotating very slowly by itself, which is why it has taken over 12 years to get all the data required. Manser explains what the researchers saw in the image:
“The image we get from the processed data shows us that these systems are truly disc-like, and reveal many structures that we cannot detect in a single snapshot. The image shows a spiral-like structure, which we think is related to collisions between dust grains in the debris disc.”
The researchers argue that systems like SDSS1228+1040 are a glimpse into the future of our own solar system when the Sun runs out of fuel. Observing these systems, we can answer questions such as: Are other planetary systems like our own? What will be the fate of our own solar system?
Professor Boris Gänsicke of the University of Warwick’s Astrophysics Group, when addressing these issues, said:
“When we discovered this debris disk orbiting the white dwarf SDSS1228+1040 back in 2006, we thought we saw some signs of an asymmetric shape. However, we could not have imagined the exquisite details that are now visible in this image constructed from twelve years of data — it was definitely worth the wait.
“Over the past decade, we have learned that remnants of planetary systems around white dwarfs are ubiquitous, and over thirty debris disks have been found by now. While most of them are in a stable state, just like Saturn’s rings, a handful are seen to change, and it is those systems that can tell us something about how these rings are formed.”