The star Arcturus is the main star in the constellation Bootes and the brightest star in the northern sky. Altogether it is the fourth brightest star in the entire sky.
Facts about Arcturus
Arcturus is 36.7 light years away from earth, which is astronomically very close. In the next four millennia, it is expected to be even more prominent and brighter as it approaches Earth. Some researchers found out that Arcturus could be a binary stars, but this has not been fully proven yet and therefore an existence over its possible companion has not been confirmed yet. Arcturus is a red giant with orange-red color and is in the final stage of its life. Its diameter is 22 times larger than the sun and it has 210 times the luminosity of the sun. Furthermore, its age is estimated at 5 to 8 billion years. This makes it twice as old as the solar system, and therefore the oldest object that can be seen with the naked eye.
Visibility of the star Arcturus
Arcturus can be seen from all continents and was probably the first star to be observed with a telescope in the daytime sky. It can be best spotted in spring and early summer in the starry sky.Écrit sur