The Star α Centauri C and the Star Groombridge 34

question 137

Multiple Choice

The star α Centauri C and the star Groombridge 34 B have the same apparent magnitude,but α Centauri C is 1.3 pc away from Earth and Groombridge 34 B is 3.5 pc away.What is the luminosity of Groombridge 34 B compared with α Centauri C? (See Figure 10-3,Comins,Discovering the Essential Universe,6th ed.)

• A) 2.7 times brighter
• B) 7.2 times fainter
• C) 2.7 times fainter
• D) 7.2 times brighter

---

Definitions:

Crenarchaeota

A phylum of Archaea that includes thermophilic, acidophilic, and psychrophilic microbes, often found in extreme environments.

Sulfur Bacteria

A group of bacteria that oxidize sulfur compounds to obtain energy, playing a key role in the sulfur cycle in the environment.

Haemophilus Bacteria

A group of bacteria that can cause various infections in humans, including respiratory infections and meningitis.

Biofilms

Complex communities of microorganisms that adhere to surfaces and are encased in a self-produced protective matrix.