Sagittarius A

Definition

Sagittarius A* (Sgr A*) is a supermassive black hole located at the center of the Milky Way Galaxy. It is approximately 4 million times the mass of the Sun and plays a crucial role in the dynamics of our galaxy.

5 Must Know Facts For Your Next Test

1. Sagittarius A* emits strong radio waves, which helped astronomers identify its location.
2. It was first discovered in 1974 by astronomers Bruce Balick and Robert Brown.
3. The Event Horizon Telescope captured the first image of Sgr A* in 2019, providing direct visual evidence of its existence.
4. Sgr A* influences the orbits of nearby stars, particularly those in the cluster known as the S-stars.
5. X-ray flares observed from Sgr A* are believed to be caused by material interacting with its intense gravitational field.

Review Questions

• What type of object is Sagittarius A* and where is it located?
• Who were the astronomers that discovered Sagittarius A*, and in what year?
• How did the Event Horizon Telescope contribute to our understanding of Sgr A*?

Related terms

Event Horizon:

The boundary around a black hole beyond which no light or other radiation can escape.

S-stars:

A group of stars orbiting very close to Sagittarius A*, useful for studying its gravitational effects.

Radio Waves:

A type of electromagnetic radiation used to detect astronomical objects like Sagittarius A*.