Nuclear bulge

Definition

The nuclear bulge is the central, densely packed region of stars in a spiral galaxy, including the Milky Way. It has a higher concentration of older stars and may contain a supermassive black hole.

5 Must Know Facts For Your Next Test

1. The nuclear bulge is typically found at the center of spiral galaxies.
2. It contains a high density of stars, many of which are older, red giants.
3. The Milky Way's nuclear bulge spans about 10,000 light-years across.
4. Astronomers believe that a supermassive black hole resides at the center of the nuclear bulge in the Milky Way.
5. Infrared observations are often used to study the nuclear bulge due to dust obscuration.

Review Questions

• What type of stars are predominantly found in the nuclear bulge?
• How wide is the Milky Way's nuclear bulge?
• Why are infrared observations useful for studying the nuclear bulge?

Related terms

Spiral Galaxy: A galaxy characterized by its flat, rotating disk with spiral arms and a central bulge.

Supermassive Black Hole: An extremely large black hole, typically found at the center of galaxies, including within their nuclear bulges.

Red Giants: A late stage in stellar evolution where a star expands and cools after exhausting hydrogen in its core.