Astronomers have discovered six objects orbiting the supermassive black hole Sagittarius A* at the center of the Milky Way galaxy, exhibiting appearances and characteristics unlike anything seen before.
The astronomical community has dubbed these “peculiar” objects as G.
Simulation of G objects around the black hole.
The first two objects, known as G1 and G2, were first observed by astronomers nearly two decades ago. This duo has unusual orbits and properties. After extended observation, researchers believe they are likely gigantic gas clouds, spanning about 100 astronomical units (the distance from the Sun to the Earth is defined as one astronomical unit). The reach of these gas clouds nearly touches the mouth of the black hole.
However, G1 and G2 do not behave like gas clouds; instead, they resemble stars, as explained by physicist and astronomer Andrea Ghez from the University of California, Los Angeles (UCLA) in 2020, according to a report by Science Alert on June 24.
Ghez and her colleagues have studied the center of the Milky Way for over 20 years. Based on this data, the team of astronomers led by expert Anna Ciurlo from UCLA discovered four additional similar objects, named G3, G4, G5, and G6.
The newly identified group of four objects orbits differently from G1 and G2. Together, the G objects have orbits ranging from 170 to 1,600 years, according to a report in the journal Nature.
To date, it remains unclear what they are and how they can exist in the vicinity of the supermassive black hole Sagittarius A* without being consumed by the “monster”.
