The Sun 1

The percentage (by mass) of the Sun that is Helium is about Select one: A. less than 1% B. 9% C. 27% D. 91% E. 71%

27%

The temperature of the layer of gas that produces the visible light of the Sun is: Select one: A. 15 million K B. 3,500 K C. 5,800 K D. 300,000 K E. 12,300 K

5,800k

About what percent of the incoming energy from the Sun' reaches Earth's surface? Select one: A. 80-100% B. 50-70% C. 70-90% D. 30-60% E. 60-80%

50-70%

The percentage (by mass) of the Sun that is Hydrogen is about Select one: A. 71% B. 9% C. less than 1% D. 91% E. 27%

71%

The percentage (by number of atoms) of the Sun that is Hydrogen is about Select one: A. 9% B. 27% C. 71% D. 91% E. less than 1%

91%

From where does most of the solar wind flow? Select one: A. prominences B. sunspots C. coronal holes D. flares E. granules

Coronal holes

The density of the Sun is most similar to which object? Select one: A. Jupiter B. Halley's Comet's nucleus C. the Moon D. the Earth E. Mercury

Jupiter

The most striking example of solar variability was the Select one: A. Maunder Minimum from 1645-1715. B. Dust Bowl drought of the 1930s. C. Joseph's seven lean years in the Old Testament. D. the fall of Rome. E. Sporer Minimum that doomed the Anasazi.

Maunder Minimum from 1645-1715

The light we see from the Sun comes from which layer? Select one: A. corona B. ionosphere C. chromosphere D. photosphere E. troposphere

Photosphere

What is it about the Sun's corona that astronomers don't understand? Select one: A. The corona is much hotter than layers of the Sun that are closer to the solar interior. B. The corona seems to absorb 2/3 of the neutrinos that pass thorough it. C. No one knows why that part of the Sun's atmosphere does not drift away into space. D. The Sun's corona extends to the outer reaches of the solar system. E. During total solar eclipses, the corona sometimes disappears from view.

The corona is much hotter than layers of the Sun that are closer to the solar interior

How many planet Earths could fit inside the Sun? Select one: A. a little over a million B. close to a billion C. 110 D. about a thousand E. almost ten million

a little over a million

How long does the sunspot cycle last, on average? Select one: A. 365.25 days B. between 25 and 35 days C. about seven years D. about 11 years E. about 76 years

about 11 years

Sunspots Select one: A. are always found close to the Sun's poles. B. were most numerous during the Maunder Minimum. C. come in pairs, representing the north and south magnetic fields. D. travel over the surface of the Sun from pole to pole. E. are relatively constant in number every year.

come in pairs, representing the north and south magnetic fields

The solar winds blow outward from Select one: A. coronal holes. B. the entire photosphere. C. sunspots. D. the Sun's poles only. E. flares.

coronal holes

The numbers of sunspots and their activity peak about every: Select one: A. 76 years. B. eleven years. C. six months. D. 36 days. E. year.

eleven years

Which of these are not associated with the active Sun? Select one: A. sunspots B. flares C. prominences D. aurora E. granulation

granulation

Visible sunspots lie in the Select one: A. granulation in the photosphere. B. transition zone. C. chromosphere. D. corona. E. radiative zone.

granulation in the photosphere

During a period of high solar activity, the corona Select one: A. cools almost to the temperature of the photosphere. B. disappears. C. shrinks to half its normal size. D. is more irregular. E. becomes smooth and even.

is more irregular

A loop of gas following the magnetic field lines between sunspots' poles is Select one: A. a prominence. B. a coronal mass ejection. C. a flare. D. a coronal hole. E. a ray.

prominence

Loops of glowing hydrogen seen hanging over the solar limb during totality are: Select one: A. prominences. B. solar rainbows. C. flares. D. haloes. E. filaments.

prominences

From inside out, which is in the correct order for the structure of the Sun? Select one: A. core, convective zone, radiative zone B. core, chromosphere, photosphere C. convective zone, radiative zone, granulation D. photosphere, radiative zone, corona E. radiative zone, convective zone, chromosphere

radiative zone, convective zone, chromosphere

When the chromosphere can be seen during a solar eclipse, it appears: Select one: A. blue. B. red. C. violet. D. invisible. E. yellow.

red

When we glimpse the chromosphere at the start and end of totality, its color is Select one: A. red, due to ionized hydrogen at lower pressure. B. yellow, like the photosphere below it. C. white from the moonlight. D. green (the famous flash). E. blue, due to the ionization of nitrogen by the magnetic fields.

red, due to ionized hydrogen at lower pressure

Suppose a large flare is detected optically. How long until radio interference arrives? Select one: A. simultaneously B. no relation between the two C. 8.5 minutes later D. about 12 hours E. about four days

simultaneously

The solar constant is a measure of Select one: A. the energy received by the Sun at any location in the solar system. B. the energy received by the Sun at the location of Earth. C. the energy emitted by the Sun at the photosphere. D. the energy received by the Sun on Earth's surface. E. the total energy emitted by the Sun in all directions.

the energy received by the sun at the location of earth

Why couldn't you stand on the Sun's surface? Select one: A. You could stand on it, if a sufficiently protective spacesuit could be designed. B. You could stand on the surface. C. The Sun has no surface at all...the photosphere is an illusion. D. The Sun doesn't have a solid surface. E. The Sun's surface is too highly magnetized for anything to survive there.

the sun doesn't have a solid surface

The luminosity of the Sun is a measure of Select one: A. the total energy emitted by the Sun in all directions. B. the energy received by the Sun at any location in the solar system. C. the energy emitted by the Sun at the photosphere. D. the energy received by the Sun on Earth's surface. E. the energy received by the Sun at the location of Earth.

the total energy emitted by the sun in all directions

Sunspots are dark splotches on the Sun. Which statement is true? Select one: A. They are extremely cold objects, as cold as Pluto. B. They are extremely hot, but cooler than the surrounding areas of the Sun. C. They are associated with areas of very low magnetic fields. D. They are hotter than the surrounding areas of the Sun. E. They are solid bodies floating on the surface of the Sun.

they are extremely hot, but cooler than the surrounding areas of the sun

While observing the Sun, you note a large number of sunspots. What can you conclude? Select one: A. This is a period of low solar activity. B. Earth's climate will be unusually cold. C. The Sun is less luminous than usual. D. The Sun's rotation is slower than average. E. There are likely to be an above average number of flares and prominences.

they are likely to be an above average number of flares and prominences

How would sunspots appear if you could magically remove them from the Sun? Select one: A. Because sunspots are dark spots, they would be invisible against the blackness of space. B. They would appear blue-white, like Sirius but brighter. C. They would shine bright orange in color, like Arcturus. D. They would shine only with reflected sunlight, appearing similar to Venus. E. They would not appear any differently than on the surface of the Sun.

they would shine bright orange in color, like Arcturus

The area in the Sun's atmosphere located above the chromosphere (1500 -10,000 km) where the temperature rises dramatically is called the Select one: A. corona. B. transition zone. C. convection zone. D. solar wind. E. photosphere.

transition zone

As the Sun rotates, an individual sunspot can be tracked across its face. From eastern to western limb, this takes about Select one: A. 12 hours. B. a week. C. two weeks. D. a month. E. 5.5 years.

two weeks