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Astronomers were able to accurately determine the distance from the Earth to the polar star
The study was published in the journal Research Notes of the American Astronomical Society, an article from Phys.org portal
. Cosmic object in many cultures after the Moon and the Sun, the distance to travel was still impossible to determine with precision. Astronomers believed that it was at a distance of 322 to 520 light-years According to the Gaia telescope, from Earth to the polar star – 447 +/- 1.6 light years
L & # The Polar Star is a system of three luminaries at once: the center of which is polar A, around which two smaller stars are rotated – Polar B and Polar Ab (or P).
In a new work, astronomers Scott Engle, Edward Guinan and Petr Harmanec analyzed the data obtained by Gaia for a B-star mass of 1.39 solar cells.
[19659003] Measurements showed that the distance up to 447 +/- 1.6 light-years, which can be applied to the entire system. The absolute magnitude of Polar B stars is 2.91. This value is slightly higher than expected from a F3V spectral type star aged 60-100 million years ago.
Astronomers also clarified the properties of the main star, Polar A: its radius is 47-50 solar, the mass is 6.4-6.7 the masses of the Sun, and the age of 55-65 millions of years.
This allowed scientists to determine that the polar star is likely to first intersect the pulsating instability band in the Hertzsprung-Russel diagram. This happens when the stars come down from the main sequence, and they can cross this band four or even five times.
"Our study of Polaris gives a clear understanding of Cepheids as a class," says Ginan. "Cepheids are fundamentally important for determining distances to galaxies and the speed of propagation of the universe: all but a few are very far away to determine their fundamental physical properties with the accuracy that Polaris now provides them."
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