Author Question: The instruments of the Mars Odyssey spacecraft detected water frozen in the soil over large areas of ... (Read 69 times)

maegan_martin · **on:** Jul 27, 2018

The instruments of the Mars Odyssey spacecraft detected water frozen in the soil over large areas of Mars.

a. True
b. False
Indicate whether the statement is true or false

Question 2

Explain how planetary nebulae and white dwarfs are related to mass loss from an aging medium-mass star.

What will be an ideal response?

rachel · **Reply #1 on:** Jul 27, 2018

Answer to Question 1

True

Answer to Question 2

When a main sequence star becomes a red giant, the outer layers are loosely held by gravity. This allows the star to lose significant amounts of mass through a strong stellar wind. This mass loss is increased during helium shell burning, when unstable conditions can cause the core energy generation to flare.The mass loss creates an expanding shell or shells of hydrogen gas moving away from the star. If the object left in the center of the expanding shell is hot enough, the gas will become ionized and glow with hydrogen emission forming a planetary nebula.After the outer layers of the star are ejected, the remaining core is not hot enough to sustain fusion. It contracts, becoming a small, hot object known as a white dwarf.