dust cloud tagged posts

When Betelgeuse, a bright orange star in the constellation of Orion, lost more than two-thirds of its brightness in late 2019 and early 2020, astronomers were puzzled.

What could cause such an abrupt dimming?

Now, in a new paper published Wednesday in Nature, an international team of astronomers reveal two never-before-seen images of the mysterious darkening — and an explanation. The dimming was caused by a dusty veil shading the star, which resulted from a drop in temperature on Betelgeuse’s stellar surface.

Led by Miguel Montargès at the Observatoire de Paris, the new images were taken in January and March of 2020 using the European Southern Observatory’s Very Large Telescope...

Schematic of the internal structure of AGB stars at the interface between the H-burning region and the convective envelope.

Scientists have identified the origin of key stardust grains present in the dust cloud from which the planets in our Solar System formed, a study suggests. Researchers have solved a long-standing puzzle concerning the source of the grains, which formed long before our Solar System and can be recovered from meteorites that fall to Earth. The stars that produced the dust were identified by observing how key reactions shaped the make-up of the grains, scientists say.

During their lifetime, stars around six times larger than the Sun – called Asymptotic Giant Branch or AGB stars – blow off their outer layers, forming an interstellar cloud of gas and dust grains...