Astronomy 109 Ch. 16 – Flashcards

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

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

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

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

The area in the Sun's atmosphere located above the chromosphere (1,500-10,000 km) where the temperature rises dramatically is called the: A. transition zone. B. corona. C. photosphere. D. solar wind. E. convection zone.

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

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

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

The Solar and Heliospheric Observatory (SOHO) is positioned: A. on the far side of the Moon. B. in a geosynchronous orbit around the Earth. C. in near-Earth orbit. D. about 1.5 million kilometers from Earth at the L1 Lagrangian Point. E. on the far side of the Sun at the L3 Langrangian Point.

By what mechanism does solar energy reach the Sun's photosphere from the layer just underneath it? A. radiation B. convection C. differentiation D. conduction E. ionization

Hydrostatic equilibrium in our Sun is the balance between: A. radiation and gravitation. B. pressure and radiation. C. convection and radiation. D. convection and gravitation. E. gravitation and pressure.

The vibrations of the Sun reveal information about: A. the magnetic field of the Sun. B. the production of energy in the Sun. C. the temperature of the core of the Sun. D. the interior structure of the Sun. E. the structure of the atmosphere of the Sun.

What two energy transport mechanisms, in order from outside the core to the surface, are found in the Sun? A. radiative diffusion, conduction B. conduction, convection C. convection, conduction D. radiative diffusion, convection E. conduction, radiative diffusion

The pattern of rising hot gas cells all over the photosphere is called: A. filaments. B. convective projections. C. prominences. D. granulation. E. sunspots.

The outward pressure of hot gas in the Sun: A. is responsible for variations in the sunspot cycle. B. weakens the magnetic field. C. is balanced by the inward gravitational pressure. D. is increasing the Sun's diameter. E. is cooling the photosphere.

On the Sun, what takes approximately 22 years to happen? A. Solar activities goes from its maximum to minimum. B. The complete sunspot cycle, including magnetic field reversals. C. The Sun takes that time to rotate on its axis. D. The corona reaches its maximum temperature and ejects gas every 22 years. E. Solar vibrations begin every 22 years.

Granulation is evidence of what phenomenon? A. hot spots in the photosphere B. convection in the solar interior C. anomalies in the solar magnetic field D. variations in the strength of the solar wind

All the photons produced in the Sun's core have been absorbed by the outer edge of what region of the Sun? A. convection zone B. core C. photosphere D. radiation zone

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

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

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

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

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

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

Why do sunspots appear dark? A. They have lower rotation rates. B. They have lower temperatures. C. They are storm systems like those on the jovian planets. D. They have lower densities

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

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

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

What is the common cause of sunspots, flares, and prominences? A. convection B. solar wind C. magnetic fields D. differential rotation

The primary source of the Sun's energy is: A. the weak force creating energy from uranium decay. B. oxidation of carbon in the core. C. dark energy. D. the strong force fusing hydrogen into helium. E. gravitational collapse of the helium coreward.

What is the primary source of energy for the Sun? A. gravitational contraction B. hydrogen fission C. carbon burning D. uranium fission E. hydrogen fusion