What Is Sgr A∗

question 8

Multiple Choice

What is Sgr A∗?

• A) a source of bright X-ray emission coming from the entire constellation of Sagittarius
• B) a source of bright radio emission in the center of our galaxy
• C) a source of bright ultraviolet light near the center of our galaxy
• D) the brightest star in the constellation Sagittarius
• E) the bulge at the center of our galaxy

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Definitions:

Ozone Layer

A stratospheric layer of ozone molecules that protects life on Earth by absorbing the majority of the sun's harmful ultraviolet radiation.

Troposphere

The lowest layer of Earth's atmosphere where weather occurs and where most aviation takes place.

Stratosphere

The layer of the Earth's atmosphere above the troposphere, extending from about 10 to 50 km above the Earth's surface, where ozone is concentrated.

Volatile Organic Compound

Organic chemicals that have a high vapor pressure at ordinary room temperature, causing significant vapor emissions that can affect air quality and human health.