Back in 2022, a team of astronomers pouring over old Gaia data found something interesting.
Gaia has been slowly mapping the Milky Way, creating a 3D map and cataloguing each stars spectrum and motion.
What the scientists were looking for, was stars heading directly for Earth ! As the Sun hurtles around our galaxy, so do all the other stars, but not always at the same speed or even in the same direction, so the stars near to us today, will slowly move away or get closer.
What the team were looking for, were yet unknown examples of stars heading towards us, what could be classed as rogue stars, not following the normal precession around the galaxy (at least, what is normal from our perspective).
They stumbled upon a white dwarf WD 0810–353 currently 36 light years from us in the constellation of Puppis, but with a very dim magnitude of 14.4, only visible to large telescopes, at least currently.
What they found was, according to Gaia, the star was heading for a very close visit in 29,000 years from now, so close, it would begin to impact on the Oort clouds sending huge amounts of material inwards towards Earth.
But the good news is, It seems the Gaia data wasn’t quite showing what the scientists thought it was. Some white dwarfs have unusually strong magnetic fields, and a recent survey of the white dwarf suggests this caused Gaia to believe it’s motion was straight at us, when in fact, the magnetic field was messing up the spectral emissions and it turns out, it may even be heading away from us.
Disaster averted, at least in 29,000 years time, but this situation isn’t unusual to Earth, we’ve had stars on our doorstep many times before, usually red dwarfs, but such stars will return again.
Looking 80,000 years into the future, Alpha Centauri will no longer be as close to us as it currently is, with Ross 128 gaining the expected crown, at least briefly.
We think of the stars as being eternal, and in many ways compared to our tiny human lives of just a 100 odd orbits around our star if we’re lucky, it’s understandable why we think of them that way, yet, they too are on a journey, around our galaxy, and future astronomers will see a very different sky to the one that’s familiar to us today.
