Messier 13 is an example of what kind of astronomical object?

Messier 13 is an example of what kind of astronomical object?

• A. Star cluster
• B. Galaxy
• C. Nebula
• D. Planet

Answer: (B)

Classifying astronomical objects by their structure and contents. Messier 13 is a globular star cluster, a dense, spherical gathering of tens of thousands (or more) stars that formed together and remain bound by gravity. It sits within our Milky Way and has little to no gas or dust, so it looks like a fuzzy ball through a telescope rather than a sprawling system. That combination—many stars tightly packed in a bounded group—fits a star cluster, not a galaxy, nebula, or planet. Galaxies are large systems with billions of stars and distinct shapes; nebulae are clouds of gas and dust, often diffuse; planets are individual bodies orbiting stars. So the object is best described as a star cluster.

Classifying astronomical objects by their structure and contents. Messier 13 is a globular star cluster, a dense, spherical gathering of tens of thousands (or more) stars that formed together and remain bound by gravity. It sits within our Milky Way and has little to no gas or dust, so it looks like a fuzzy ball through a telescope rather than a sprawling system. That combination—many stars tightly packed in a bounded group—fits a star cluster, not a galaxy, nebula, or planet. Galaxies are large systems with billions of stars and distinct shapes; nebulae are clouds of gas and dust, often diffuse; planets are individual bodies orbiting stars. So the object is best described as a star cluster.