Is a white dwarf heading towards our solar system? Researchers have new knowledge

  1. homepage
  2. Know

Split

The approach of the dwarf star WD 0810-353 to our solar system caused a stir. Now researchers are correcting the planned route.

Armagh, a celestial body hurtling towards our solar system and capable of causing great chaos, seems like a setting straight out of a science fiction novel. But the scenario is real, or at least one research team believed it was real based on their data. In fact, it now turns out that the calculations had forgotten an important factor. A second research team has done the calculations and has now given the go-ahead.

“Have you ever wondered if other stars could get close enough to our solar system to stir up small bodies in the outer solar system?” asks John Landstreet, an astronomer at the Armagh Observatory and Planetarium, in a statement. Landstreet is the lead author of a study showing that this scenario can be ruled out, at least for the white dwarf star WD 0810-353.

The white dwarf appears to be headed straight for the solar system

But first another study showed the opposite: the white dwarf star with the complicated name is apparently heading directly towards our solar system, an analysis of data from the “Gaia” mission showed. In about 29,000 years, the white dwarf should encounter our solar system at a distance of only 31,000 astronomical units (about 4.65 billion kilometers). For comparison, the closest star to us, Proxima Centauri, is about 4.2 light years away (i.e. 39.7 trillion kilometers).

A white dwarf star in space. (Artist’s impression) © IMAGO/Zoonar.com/Linda Brotkorb

For us humans, this is a distant future and an almost unfathomable distance, but from an astronomical point of view it represents only a brief moment and a small leap: our solar system formed about 4.6 billion years ago. And only in another five billion years will the Sun become a red giant and herald the end of the Earth.

Now, the new study carried out by the Landstreet team and published in the specialized magazine shows Astrophysical diary He published, however, something completely different. “We discovered that the approach speed measured by the ‘Gaia’ project is incorrect and that the predicted close encounter between WD0810-353 and the Sun will not occur,” explains co-author Stefan Bagnulo. “In fact, WD0810-353 may not be moving toward the Sun at all.”

The white dwarf star has a strong magnetic field; this has been overlooked

The fact that the white dwarf has a strong magnetic field seems to have been overlooked. “In astronomy, magnetic fields are crucial to understanding many physical aspects of a star, and ignoring them can lead to erroneous interpretations of physical phenomena,” explains astronomer Eva Villaver.

If the star really came within 31,000 astronomical units (AU) of our solar system, it would be in the middle of the Oort cloud. This is a region of icy debris surrounding the solar system at a distance of approximately 2,000 to 100,000 AU. Long-period comets that take more than 200 years to orbit the Sun probably originate from the Oort cloud.

The Oort Cloud surrounds the solar system like a shell.  In it there are countless pieces of ice, some of which continue their path towards the Sun, in the form of long-period comets.  The graph shows the supposed trajectory of comet C/2014 S3 (Panstarrs).
The Oort Cloud surrounds the solar system like a shell. In it there are countless pieces of ice, some of which continue their path towards the Sun, in the form of long-period comets. The graph shows the supposed trajectory of comet C/2014 S3 (Panstarrs). ©ESO/L. Calcada

A star in the Oort cloud could push comets towards Earth

The problem: If a star passes through the Oort cloud, it could change the orbits of the icy debris and, in the worst case, send chunks of rock on a collision course with Earth or other planets in the solar system. However, this is unlikely to happen for another 29,000 years, the new study shows. Researcher Bagnulo reassures himself: “This is one less cosmic danger we have to worry about!” (eyelash)

Mechanical assistance was used for this article written by the editorial team. The article was carefully reviewed by editor Tanja Banner before publication.

Leave a Comment