Tag Archives: Gliese 710

Star to get within a trillion miles of Sun in 1.4 million years

Using the precise location and motion data obtained by the space telescope Gaia, astronomers have identified a star that 1.4 million years will come within a trillion miles of the Sun.

That distance puts it well within the outer parts of the theorized Oort cloud at the edge of the solar system. Since the star, Gliese 710, has a mass half that of the Sun, it will thus disturb many objects in that Oort Cloud, causing many to eventually fall sunward and produce a hail of comets several million years later. It will be, for a long time, the brightest object in the night sky, by far.

The data also identified a number of other stars that have in past or will in the future get close to the Sun. The most important result is not that these close approaches occur, but that they have found that they are relatively rare, and even the closest, Gliese 710, never really gets that close.

The universe is big, far bigger than we can really imagine.

Astronomers identify 25 stars that have or will come within 3 light years of Sun

Using the second data release from Gaia, astronomers have identified 25 stars that have or will come within 3 light years of Sun sometime within fifteen million years.

But the authors are confident that the 25 stars represent only a sliver of the actual encounters that have occurred over this time period. “They’re still just scratching the surface,” Mamajek agrees. That’s because the Gaia satellite eliminates low-mass stars (which are simply too faint to see at the moment) and high-mass stars (which are often so bright they saturate the satellite’s detectors) — thus limiting the data to stars that range between 0.5 and 1.3 times the mass of the Sun.

As such, the team suspects that they have only spotted 15% of all the encounters that likely pummel our solar system. “It’s a good first step, but one should not look at this as the final word,” Mamajek adds.

In reading their paper (available here), they identify three stars come come within a light year, therefore disturbing the theorized Oort Cloud of comets thought to exist at this distance from the Sun. One, Gliese 710, will do so in 1.3 million years..