Context: Researchers have noted on three extraordinary occasions this year that Sagittarius A*, the black hole showed unusual behaviour. The area immediately outside Sagittarius A* is becoming twice as bright as compared to any previously recorded instance.
GS- 3 Awareness in the fields of IT, Space, Computers, robotics, nano-technology, bio-technology and issues relating to intellectual property rights.
- According to Albert Einstein’s theory of general relativity, black holes are uninhabitable chasms of spacetime that end in a ‘singularity,’ or a mass of infinite density.
- Black holes, with gravitational fields so powerful that not even light could escape them, were inferred by quantum physics about a century ago.
- It’s a place so bleak that even the laws of physics break down there.
- According to scientist estimates, there are approximately 100 million black holes in our galaxy, however, none of them are close enough to Earth.
- The gravitational forces of them are so strong that nothing, neither matter nor light, can escape once it gets too close.
- It is at the center of the Milky Way galaxy which has four million times the mass of the sun.
- A supermassive black hole that sits 26,000 light-years away from Earth, near the Galactic Center, or the center of the Milky Way.
- It is one of the few black holes where we can witness the flow of matter nearby. This has been made possible with the help of Event Horizon Telescope.
- Since the discovery of Sagittarius A* 24 years ago, it has been fairly calm.
- This year, however, Sagittarius A* has shown unusual activity, and the area around it has been much brighter than usual.
- It may be that the Sagittarius A* has become hungrier, and has been feeding on the nearby matter at a markedly faster rate, which one researcher described as a “big feast”. A black hole does not emit light by itself, but the matter that it consumes can be a source of light.
Event Horizon Telescope
- The Event Horizon Telescope is an international collaboration aiming to capture the first image of a black hole by creating a virtual Earth-sized telescope.
- Instead of constructing a giant telescope EHT links radio dishes across the globe to create an Earth-sized interferometer to measure the size of black holes.
- The EHT project includes theoretical and simulation studies that are framing questions rooted at the black hole boundary.
- The following are two massive black holes photographed by EHT
- Sagittarius A* – It is at the center of Milky Way galaxy which has four million times the mass of sun.
- Monster black hole – It is in an elliptical galaxy known as M87, and it is 1500 times more massive than Sag A*.