360-degree video puts you at the center of the galaxy
A newly released 360-degree video lets you explore the Milky Way from the perspective of the supermassive black hole at its heart known as Sagittarius A* (Sgr A*). The immersive simulation examines how a population of massive stellar bodies, known as Wolf-Rayet stars, behave as they circle the black heart of our galaxy.
Stars are quirky, volatile, and at least in the case of our own Sun, life-nurturing celestial bodies. From our perspective here on Earth looking up at the night's sky, the vast distances separating us from these stellar bodies make them all appear, by and large, the same. Thankfully, powerful earthbound and orbital telescopes have granted mankind the ability to cross the light-years of distance isolating us from the surrounding cosmos, and reveal the magnificently diverse nature of those distant motes of light.
The video was created from data on the galactic centre collected by multiple telescopes, including the ESO's Very Large Telescope (VLT) and NASA's Chandra X-ray observatory. It focuses on a particularly rare and impressive population of stellar bodies, known as Wolf-Rayet stars, orbiting Sgr A*, near the galactic centre.
The video is best experienced with the help of a VR headset, but you can also watch it on your computer or smartphone.
A Wolf-Rayet star has an active, but relatively short existence, during which it sheds mass at a phenomenal rate as material its surface is ejected in powerful stellar winds. When the winds from two neighboring stars collide, shock waves super heat the gas embedded in the winds, causing it to glow in X-ray light.
In the visualization, roughly 25 Wolf-Rayet stars can be seen as bright white points of light, orbiting roughly 1.5 light years out from Sgr A*. The gas carried in the stellar winds ejected by the monster stars is represented in red and black. Yellow features denote clumps of stellar material in the process of spiralling toward Sgr A*.
The video covers the movements of the stars and material over a 500 year period, from 350 years in the past to 150 years into the future, and includes two distinct scenarios. In the first simulation Sgr A* is calm, and in the second, the supermassive black hole violently expels its own material. This in turn dispels much of the gas contained in the stellar winds, which would otherwise have collided, clumped together, and eventually "fed" Sgr A*.
An international team of researchers used the simulation in conjunction with theoretical modeling in an attempt to shed light on the nature of a set of disk-shaped X-ray emissions that had previously been detected for a distance of 0.6 light-years around Sgr A*.
They discovered that the amount of X-rays emitted by the gas in the region varies significantly depending on the strength and frequency of outburst activity from Sgr A*. The finding suggest the supermassive black hole experienced a fairly strong outburst some time in the last few centuries that, even though it stopped about 100 years ago, is still affecting the surrounding region.
A paper detailing the research has been published in the Monthly Notices of the Astronomical Society.