Chandra Observes Sgr A* Rejecting Material

Chandra Observes Sgr A* Rejecting Material

Sgr A* – the supermassive black hole sitting in the center of the Milky Way – is often referred to as a ‘starved’ black hole, meaning that it swallows very little of the nearby cosmic gas and dust. The authors of this paper observed Sgr A* with the Chandra X-ray telescope for 3 mega seconds, throughout which only 1% of the gas available to Sgr A* actually accreted onto the black hole. It swallows cold gas, while rejecting hot gas – ejecting the matter back into space.

Birth of the Most Massive Star Known – Caught in Action

Birth of the Most Massive Star Known – Caught in Action

The formation of massive stars is still an intense topic of debate. Observations are difficult because massive star forming regions are heavily obscured by dust – invisible in the optical and near infrared. The trick is to look at much longer wavelengths. Today’s paper does just that, using the Atacama Large Millimeter Array (ALMA) in Chile to observe the birth of a massive star in submillimeter wavelengths. At 500 times the mass of the Sun and 1 million times brighter, it is the largest forming protostar ever seen in our galaxy.

The black hole and the 50-course meal

The black hole and the 50-course meal

The authors of today’s paper investigate the feeding habits of the elusive quiescent supermassive black hole, finding that in addition to swallowing some stars whole and constantly snacking on the winds of other stars, some black holes may also dine on giant stars slowly disrupted over tens to hundreds of orbits.