Gliese 710

I'm writing about this because it shows that nothing stays the same when it comes to the universe, our galaxy, and our solar system. It also speaks to the idea that we're not completely safe on this nice little planet we call home. All of this is based on observations and calculations.

In 1.35 million years a star from the constellation Serpena Cauda will pass through our solar system's Oort cloud and set off a horrendous attack on our planet from comets. Right now, Gliese 710, a K7 Vk class star 0.6 the mass of our sun and 0.084 times its luminosity, is presently 63.8 light years away. In 1.35 million years from now it will pass within 13000 AU of our sun. This is only 77 light days away. Remember that an AU or astronomical unit is the distance from Earth to the Sun. The Oort cloud supposedly extends out at least a light year so this star will pass right though it and kick many icy comets out of the cloud and send them into the inner solar system where they will be able to collide with the Earth as well as many of the other planets.

The calculations indicate that there is an 80% chance that Gliese 710 will pass through the Oort cloud within 1.104 light years + or - 0.545 light years of the Sun. There is also a 1 in 10,000 chance this star will pass less than 1,000 AU and pass within the Kuiper belt.

The good news is that it will not pass close enough to change the orbits of the planets in our solar system. However, there are trillions of icy objects in the Oort cloud and they could cause a big problem if they invade the inner solar system. The estimate is that 2.4 million of these comets could be forced to cross Earth's orbit around the sun within a couple of million years, making a collision event very possible.

The other good news is that an analysis of the motions of 35,000 stars within 100 light years of the Sun failed to find another possible risk within a few million years. The Centauri stars will pass closer but not pose a threat.
That makes me feel a lot better.

Thanks for reading.