New data from the European Space Agency’s (ESA)
Gaia mission has given astronomers unprecedented accuracy in predicting
that Gliese 710, a K-spectral type star a little more than half the size
of our Sun, will cross into our solar system’s Oort Cloud of comets
some 1.35 million years from now.
According to a paper recently published in the journal Astronomy & Astrophysics, Gliese 710 will swipe through a swath of the Oort Cloud’s estimated few trillion comets, which in turn circle our solar system at distances of up to a light year.
The co-authors, Filip Berski and Piotr Dybczński, write that their calculations indicate that Gliese 710, currently estimated to be some 64 light years away in the constellation of Serpens, will have the strongest influence on the Oort Cloud objects in the next 10 million years. They note that their calculations also indicate that Gliese 710 will pass 13,365 astronomical units (or Earth-Sun distances) from the Sun .
Comet
McNaught as seen from the European Southern Observatory’s Very Large
Telescope in Chile’s Atacama desert; January 2007. Credit: S.
Deiries/ESO
At its minimum distance, the paper’s co-authors note that of objects formed outside the solar system, Gliese 710 will appear as the brightest and the fastest object on the night sky. The resulting Gliese 710 flyby, they write, will generate a large flux of new long-period Oort Cloud comets , many of which will be able to reach the inner part of the solar system.
As noted in my book “Distant Wanderers,” these comets will only gradually arrive in our vicinity over a period of some two million years. Some will be swept up by Jupiter’s gravity; others will repeatedly circle the Sun. A few will be flung out of the solar system altogether. With the new Gaia data, the team’s galactic computer simulations provide new parameters of the coming close encounter with Gliese 710.
“Gliese 710 will trigger an observable cometary shower with a mean density of approximately ten comets per year, lasting for three to 4 million years,” the co-authors write.
Floor van Leeuwen, an astronomer at Cambridge University in the U.K., who was not affiliated with the research, calls the paper “a sound study, with expected improvements over HIPPARCOS (High Precision Parallax Collecting Satellite), ESA’s last astrometric measuring mission. He told me that this new Gaia data combined with HIPPARCOS’ own position measurements of the same stars, provides astronomers with a very accurate determination of many nearby stars’ proper motions. That is, how the stars appear to move across our line of sight when compared to more distant background objects.
But is this really the star that will make the closest and quickest approach to our solar system?
Van Leeuwen, however, cautions that there are still many faint red dwarf stars whose exact trajectories and movements across the sky that still remain very much unknown.
With time, van Leeuwen says Gaia will observe and measure most of them to accuracies compatible with or better than what is now possible for Gliese 710.
“It’s likely that among those many stellar dwarfs, there will also be others on a close encounter course with our solar system,” said van Leeuwen. “We just have not yet identified and measured those stars.”
According to a paper recently published in the journal Astronomy & Astrophysics, Gliese 710 will swipe through a swath of the Oort Cloud’s estimated few trillion comets, which in turn circle our solar system at distances of up to a light year.
The co-authors, Filip Berski and Piotr Dybczński, write that their calculations indicate that Gliese 710, currently estimated to be some 64 light years away in the constellation of Serpens, will have the strongest influence on the Oort Cloud objects in the next 10 million years. They note that their calculations also indicate that Gliese 710 will pass 13,365 astronomical units (or Earth-Sun distances) from the Sun .
Comet
McNaught as seen from the European Southern Observatory’s Very Large
Telescope in Chile’s Atacama desert; January 2007. Credit: S.
Deiries/ESO At its minimum distance, the paper’s co-authors note that of objects formed outside the solar system, Gliese 710 will appear as the brightest and the fastest object on the night sky. The resulting Gliese 710 flyby, they write, will generate a large flux of new long-period Oort Cloud comets , many of which will be able to reach the inner part of the solar system.
As noted in my book “Distant Wanderers,” these comets will only gradually arrive in our vicinity over a period of some two million years. Some will be swept up by Jupiter’s gravity; others will repeatedly circle the Sun. A few will be flung out of the solar system altogether. With the new Gaia data, the team’s galactic computer simulations provide new parameters of the coming close encounter with Gliese 710.
“Gliese 710 will trigger an observable cometary shower with a mean density of approximately ten comets per year, lasting for three to 4 million years,” the co-authors write.
Floor van Leeuwen, an astronomer at Cambridge University in the U.K., who was not affiliated with the research, calls the paper “a sound study, with expected improvements over HIPPARCOS (High Precision Parallax Collecting Satellite), ESA’s last astrometric measuring mission. He told me that this new Gaia data combined with HIPPARCOS’ own position measurements of the same stars, provides astronomers with a very accurate determination of many nearby stars’ proper motions. That is, how the stars appear to move across our line of sight when compared to more distant background objects.
But is this really the star that will make the closest and quickest approach to our solar system?
Van Leeuwen, however, cautions that there are still many faint red dwarf stars whose exact trajectories and movements across the sky that still remain very much unknown.
With time, van Leeuwen says Gaia will observe and measure most of them to accuracies compatible with or better than what is now possible for Gliese 710.
“It’s likely that among those many stellar dwarfs, there will also be others on a close encounter course with our solar system,” said van Leeuwen. “We just have not yet identified and measured those stars.”
- View Original
- December 22nd, 2016
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