Giant star

Giu 14 2021

Mysterious shadow hides giant star

VVV-WIT-08 is a red giant star with 100 solar masses and 25,000 light years away from us. Ten years ago (25,010 years ago, of course) its brightness suddenly decreased drastically - down to one-thirtieth of its original value. There are indeed variable stars. In certain phases of life many types of stars show spontaneous changes. However, such a large decrease as in VVV-WIT-08 is rare. It speaks for the fact that the cause was not in the star itself, but in its environment. Did another object move in front of the star for a few hundred days and darken…

Astrophysics

Lug 30 2020

In the orbit of two giants

Eta Carinae, approximately 7500 light-years from Earth, has everything that an astronomer could want. First, there’s the nebula surrounding Eta Carinae. The so-called Homunculus Nebula is still growing. It has the shape of two opposing cones, whose tips originate in Eta Carinae, and measures more than 0.5 light-years from end to end. From the propagation rate of up to 700 km/s, the existence of the nebula can be traced back to an outburst in the 1840s. Second, it is not just a single star, but a binary system consisting of two blue giants. The primary star has a mass…