week 9
Which of the following is NOT a product of the first step in the p-p chain of nuclear fusion?
a form of helium
Astronomers have found that the level of the Sun's activity varies over the centuries. How did they come to realize that this is from:
all of the evidence listed was collected
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
Which part of the Sun's atmosphere has the lowest density (number of atoms per unit volume)?
cornoa
Which part of the Sun's atmosphere is the hottest?
corona
The ten million tons of particles that escape the Sun each year in the form of the solar wind get out mainly through regions called
coronal holes
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
Today we realize that the source of energy for the Sun is a process called
nuclear fusion
The Sun is an enormous ball of gas. Left to itself, a ball of so many atoms should collapse under its own tremendous gravity. Why is our Sun not collapsing?
nuclear fusion in the core keeps the temperature and the pressure inside the Sun at a high enough level so that gravity is balanced
The material inside the Sun is in the form of a
plasma
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
What mechanisms do astronomers believe is responsible for making the Sun's outer atmosphere so much hotter than its photosphere?
the Sun's magnetic field interacting with the charged particles that make up the atmosphere
A friend (who does not have the new awareness which you have gained from this course) suggests that the mechanism that keeps the Sun shining as brightly as it does is the burning of coal. You brilliantly challenge his theory! Your challenge comes in several related steps; which of the following is one of those steps?
the dating of radioactive rocks show that the Earth and thus the Sun are billions of years old
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