The approach of the dwarf star WD 0810-353 to our solar system has caused excitement. Now researchers are correcting the predicted path.
Armagh – A celestial body hurtling towards our solar system and capable of causing great chaos: it seems like the setting of a science fiction novel. But the scenario is real, or at least one research group believes it is real based on their data. Indeed, it now turns out that the calculations had forgotten an important factor. A second research group has done the math and has now given the green light.
“Have you ever wondered whether other stars might come so close to our solar system that they lift small bodies into the outer solar system?” asks John Landstreet, an astronomer at Armagh Observatory & 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 heading directly towards the solar system
But first another study showed something the opposite: The complicatedly named white dwarf star was apparently heading directly towards our solar system, an analysis of data from the “Gaia” mission showed. In about 29,000 years, the white dwarf is expected to 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 (or 39.7 trillion kilometers).
For us humans this is a distant and almost unfathomable future, but astronomically 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 turn into a red giant and herald the end of the Earth.
This is now demonstrated by the new study carried out by the Landstreet team and published in the specialized magazine Astrophysics Journal published, however, something completely different. “We found that the approach velocity measured by the ‘Gaia’ project is incorrect and the predicted close encounter between WD0810-353 and the Sun will not actually occur,” explains co-author Stefan Bagnulo. “In fact, WD0810-353 may not move toward the Sun at all.”
The white dwarf star has a strong magnetic field: this has been overlooked
It seems that the fact that the white dwarf has a strong magnetic field has been overlooked. “In astronomy, magnetic fields are crucial to understanding many physical aspects of a star, and ignoring them can lead to misinterpretations of physical phenomena,” explains astronomer Eva Villaver.
If the star were actually 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 between 2,000 and 100,000 AU. Long-period comets that take more than 200 years to orbit the sun probably originate from the Oort cloud.
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 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, according to the new study, this is unlikely to happen before 29,000 years. Researcher Bagnulo reassures himself: “This is one less cosmic danger we have to worry about!” (form)
For this article written by the editorial staff, mechanical assistance was used. The article was carefully checked by editor Tanja Banner before publication.