Astronomy 15 and 16

Astronomers have concluded that the Sun's activity varies in an 11-year cycle. Which of the following statements about this cycle is TRUE:

The number of sunspots gets larger and smaller over the course of 11 years

When did scientist begin to understand how the Sun produces all the energy that it does?

The process was not well understood until the 1930's

Which of the following is NOT a product of the first step in the p-p chain of nuclear fusion?

a form of helium

At the end of the p-p chain of nuclear fusion in the Sun, hydrogen nuclei have been converted into:

a helium nucleus

According to the formula E=mc2

a little bit of mass can be converted into a substantial amount of energy

Who pays the bill for the energy generated by nuclear fusion in the Sun? In other words, where does the energy pouring out of the Sun come from ultimately?

a little bit of mass is lost in each fusion reaction and is turned into energy (the Sun is losing mass

Which of the following particles has the lowest mass?

a neutrino

Which of the following, produced at the core of the Sun, will take the shortest time to emerge from the Sun's photosphere (surface)?

a neutrino

Physicists Kelvin and Helmholtz in the last century proposed that the source of the Sun's energy could be:

a slow contraction

Solar wind particles can be captured by the Earth's magnetosphere. When these particles spiral down along the magnetic field into the atmosphere, they are responsible for:

aurorae (northern and southern lights)

Astronomers first detected the presence of a wind of particles coming from the Sun by

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

Coronal Mass Ejections from the Sun have many serious effects on or near the Earth. Which of the following is NOT one of these effects?

causing huge cyclones around the equator of the Earth

The hotter region directly above the Sun's visible surface is called the

chromosphere

When great currents of hot material rise inside the Sun (and cooler material sinks downward), energy is being transferred by a process known as:

convection

The hottest zone in the Sun is the

core

Which part of the Sun's atmosphere has the lowest density (number of atoms per unit volume)?

corona

Which part of the Sun's atmosphere is the hottest?

corona

The Sun's chromosphere and corona were discovered

during total eclipses of the Sun

Recently, some engineers and scientists have proposed building spaceships with enormous "sails" that catch the solar wind and use it to move the ship. What kinds of particles would be hitting this sail (i.e., what is the solar wind mostly made of):

electrons and protons

In the Sun, when a positron and an electron collide, they will produce:

energy in the form of a gamma ray

Astronomers have found that the level of the Sun's activity varies over the centuries. How did they come to realize that this is so:

historical records of the number of sunspots seen on the Sun measuring the amount of radioactive carbon in tree rings historical records of auroral activity

The granulation pattern that astronomers have observed on the surface of the Sun tells us that:

hot material must be rising from the Sun's hotter interior

The most common element in the Sun is

hydrogen

As astronomers have learned more about the structure of the Sun, they have found that it

is made entirely of hot gas

What happens to the positron created during the p-p chain of nuclear reactions inside the Sun?

it quickly collides with an electron and turns into gamma-ray energy

Astronomers now realize that active regions on the Sun are connected with

loops of magnetic field emerging from the surface of the Sun

The Global Oscillations Network Group (GONG) Project is engaged in:

measuring the pulsations of the Sun from stations around the world

When a large nucleus breaks apart (or is broken apart) into two smaller pieces, this is called

nuclear fission (you got this wrong)

Today we realize that the source of energy for the Sun is a process called

nuclear fusion

When we use the light of atoms such as hydrogen and calcium to examine the Sun's outer layers, we can see bright "clouds" in the chromosphere right around the location of sunspots. These bright clouds are given the name:

plages

The antimatter version of an electron is called a

positron

Which of the following is NOT one of the fundamental particles that we find inside atoms

positrons

Which of the following is a way for astronomers to learn more about the interior of the Sun?

study the oscillations (pulsations) witnessed on the Sun's surface

Which part of the Sun has the greatest density?

the core

The strongest force we know of in physics is

the nuclear force which holds nuclei together

The Sun s photosphere is

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

In the formula E=mc2, the letter c stands for

the speed of light

Sunspots are darker than the regions of the Sun around them because

they are cooler than the material around them (although still very hot compared to Earth temperatures)

The process of fusion that keeps our Sun shining begins with which building blocks?

two protons