Avi Blizovsky
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Astronomers say that the Sun's twin star is in the left pinnacle of Scorpio. It is about the star 18 Scorpii located in the region of the sky defined as the Scorpion group, at a distance of 46 light years from the Earth, which is a relatively short distance in cosmic terms.
Astronomers have been looking for stars very similar to our Sun for years, because stars identical to the Sun may have a system of planets and possibly even a twin brother to Earth, which could also be a good place to look for extraterrestrial life.
18 Scorpii has been in the spotlight especially since 1997, when scientists identified it as a potential twin. On Tuesday, a group of astronomers from the University of Pennsylvania's Villa Nova University said they had studied the star and found many things it and the Sun had in common. Both are about the same age - 4-5 billion years; Both have roughly the same mass, the same radius, and a similar surface temperature. It takes them about the same time to rotate around themselves, about 25 days; They have a similar cycle of activity - in the case of the sun, these are sunspots.
Edward Guinan of Villa-Nova says that finding the star most similar to the sun is a kind of sport, but it also has scientific value. "Finding an identical twin to the Sun shows that the Sun is a normal star," Guinan said at a meeting of the American Astronomical Society in Atlanta.
A near-twin of the Sun
Are the Sun and the star 18 Scorpio twins separated at birth? not exactly. This star, dimly visible to the naked eye in the constellation Scorpius, is 46 light-years from Earth. But it is almost a twin of the Sun, astronomers reported yesterday at the American Astronomical Society conference in Atlanta.
The mass of the sun is about 2.2 billion billion billion tons; The mass of 18 Scorpii is greater than it by about 11 percent. The spots on the sun fill and diminish every 13 years; A similar cycle, lasting nine to 18 years, occurs in the spots of 26 Scorpions. The sun rotates around an axis every 18 days; 23 Scorpio revolves on its axis every 5,504 days. Other points of similarity include the temperature of the surface (5,515 degrees Celsius in the Sun, and probably about 18 degrees in 1,392,000 Scorpii); The diameter (the diameter of the sun is about 18 km, that of 1,416,000 Scorpio - 4.56 km); and the age (the age of the Sun is 18 billion years; the age of 4.2 Scorpio is XNUMX billion years).
Overall, 18 Scorpii is "very, very similar" to the Sun, according to Ryan Hamilton, a student at Villanova University who co-authored the study. This study confirms in more detail the conclusions of another team of astronomers from 1997.
It is not yet known if any planets orbit 18 Scorpii. Planetary researchers are following it, but much more research is needed to understand whether 18 Scorpii has a solar system equivalent.
New York Times
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