Suppose the X-Ray Signal from a Quasar Fluctuates with a Period

question 78

Multiple Choice

Suppose the X-ray signal from a quasar fluctuates with a period of 3 hours. What is the maximum size of the source?

• A) 150,000 km, about the diameter of Jupiter
• B) 10.8 au, about the diameter of Jupiter's orbit
• C) 4.5 ly, about the distance between the Sun and the nearest star
• D) 10,800 ly, a tenth the size of the Milky Way Galaxy

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Definitions:

Earth's Atmosphere

The layer of gases surrounding the Earth, essential for life, and protecting it from harmful solar radiation.

Fossil Fuels

Natural fuels such as coal, oil, and natural gas, formed from the decomposed remains of ancient plants and animals, used for energy.

Minerals

Naturally occurring, inorganic solids with a definite chemical composition and a crystalline structure found in the earth.

Earth Layers

The division of the interior of Earth into layers, including the crust, mantle, outer core, and inner core, based on chemical and physical properties.