Ch. 15 Stars

Which of the following statements about the Sun's photosphere is NOT TRUE? a. The photosphere is significantly hotter than all the layers of the Sun beneath it (further inward) b. The photosphere is not a solid layer; if a spaceship (that could withstand the heat) fell through it, it wouldn't feel anything when reaching the photosphere c. The photosphere is much less dense than our Earth's atmosphere d. The photosphere is the layer where the Sun becomes opaque (you can't see through it) e. Through a telescope, the photosphere looks mottled or granulated

a. The photosphere is significantly hotter than all the layers of the Sun beneath it (further inward)

The hotter region directly above the Sun's visible surface is called the a. chromosphere b. photosphere c. corona d. ionization region e. convection zone

a. chromosphere

Which part of the Sun's atmosphere has the lowest density (number of atoms per unit volume)? a. corona b. transition region c. chromosphere d. just above the photosphere e. you can't fool me, all these regions are at roughly the same density

a. corona

You are out on the beach, enjoying the warm sunshine with friends. As you glance up at the Sun, the part of the Sun that you can see directly is called its: a. corona b. photosphere c. chromosphere d. core e. heliopause

b. photosphere

The Sun's chromosphere contains many jet-like projections that stick up into the transition region. These spikes of gas are called: a. coronae b. spicules c. plages d. flares e. prominences

b. spicules

As you go upwards from the Sun's photosphere, a. the temperature decreases b. the density (number of atoms in a unit volume) decreases c. the layers get easier to see with the unaided eye d. the kinds of atoms present change drastically e. only red light can emerge

b. the density (number of atoms in a unit volume) decreases

The Sun's photosphere is a. the central region where the energy of the Sun originates b. the part of the Sun from which the light comes that we see when we look at the Sun with our eyes c. the hottest region of the Sun d. the outermost layers of the Sun's atmosphere e. the first region you would come to when leaving the core

b. the part of the Sun from which the light comes that we see when we look at the Sun with our eyes

The hottest zone in the Sun is the a. photosphere b. radiative zone c. core d. convection zone e. chromosphere

c. core

Which part of the Sun's atmosphere is the hottest? a. chromosphere b. transition region c. corona d. just above the photosphere e. you can't fool me, all these regions are at roughly the same temperature

c. corona

The Sun's chromosphere and corona were discovered a. using the first telescopes Galileo built b. in the late 19th century through the use of a spectrograph c. during total eclipses of the Sun d. using spacecraft that orbited Venus, a planet with a better view of the Sun e. by ancient shepherds, who saw reflections of the Sun in quiet pools of water

c. during total eclipses of the Sun

The most common element in the Sun is a. helium b. iron c. hydrogen d. water e. nitrogen

c. hydrogen

What mechanisms do astronomers believe is responsible for making the Sun's outer atmosphere so much hotter than its photosphere? a. stirring by comets, meteors, and other pieces of solid material being pulled in by the Sun's strong gravity b. light reflected back from the terrestrial planets c. the Sun's magnetic field interacting with the charged particles that make up the atmosphere d. the ionization of a new element called coronium e. astronomers really don't have even a guess about what heats the Sun's outermost layers

c. the Sun's magnetic field interacting with the charged particles that make up the atmosphere

As astronomers have learned more about the structure of the Sun, they have found that it a. has a small solid core inside b. is made entirely of liquid, with a tiny bit of hot gas on the outside c. is solid throughout, but with a large very hot atmosphere d. is made entirely of hot gas e. is made of billions of individual pieces of hot rock, all orbiting around each other in a whirling arrangement

d. is made entirely of hot gas

Astronomers first detected the presence of a wind of particles coming from the Sun by a. sending a spacecraft much closer to the Sun than the planet Mercury b. by noting its effects on the atmosphere of Venus c. by dramatic and sudden changes in the spectrum of coronium d. using the experiments aboard Sputnik 1, the first spacecraft to go above the Earth's atmosphere e. by noting the wind's effects on the tails of comets

e. by noting the wind's effects on the tails of comets

How do astronomers know what the outer layers of the Sun are made of? a. we send graduate students there to get samples b. several spacecraft with good shielding have approached the Sun and obtained samples c. the surface layers of Mercury have been laid down by the Sun and are thus made of the same material as the Sun d. the Sun's wind gives us an accurate measure of all the different elements in the Sun e. we take an absorption line spectrum of the Sun, and the absorption lines tell us what elements are present in the outer layers

e. we take an absorption line spectrum of the Sun, and the absorption lines tell us what elements are present in the outer layers