Apparent and absolute magnitude

Diagram 1 shows a Hertzsprung–Russell (HR) diagram.

Draw a cross to show the position of the Sun on the HR diagram.

In approximately 4 billion years, the Sun will enter the next stage of its evolution.

Draw a circle on the HR diagram around the area that will include the Sun in the next stage of its evolution.

Describe the stars that are in the top left corner of the HR diagram.

Diagram 2 shows how the brightness of two stars, star A and star B, changes with time.

These stars are called Cepheid variables.

Determine the period of the variation in brightness for these stars.

Calculate the frequency of the variation in brightness for these stars.

State what is meant by the term absolute magnitude.

Star A and star B have the same absolute magnitude but star A is always brighter than star B in the night sky.

Explain how this is possible.

This question is about stars.

The diagram shows an incomplete Hertzsprung-Russell (H-R) diagram.

Label the axes on the diagram.

There are three shaded areas on the diagram.

State the name of the shaded area that contains the Sun.

Which star is a white dwarf?

At a standard distance from the Earth, which star is brighter than the Sun and has a greater surface temperature than the Sun?

The Hertzsprung-Russell (HR) diagram shown can be used to classify stars.

Three regions in the HR diagram are labelled P, Q and R.

The boxes show the three regions and different astronomical objects.

Draw a straight line from each region to the type of astronomical object contained in that region.

Define the term absolute magnitude.

This question is about stars.

The table gives some information about four stars.

Star C is much more powerful than star A.

Stars A and C appear to have the same brightness when viewed from Earth.

Suggest how this is possible.

Using information from the table, explain which star is in the supernova stage of its evolution.

Explain how a main sequence star evolves into a supernova.

Astronomers have used supernovas in distant galaxies to investigate the expansion of the universe.

Light emitted from a supernova at a wavelength of 7.77410^–7m was detected at Earth with a wavelength of 7.78010^–7m.

Calculate the speed at which the galaxy containing this supernova was moving away from the Earth.

[speed of light = 3.010⁸m / s]

The astronomers investigated supernovas that showed a red-shift in the wavelengths detected in different galaxies.

The astronomers discovered that the red-shifted light detected from supernovas in nearby galaxies had shorter wavelengths than the red-shifted light detected from supernovas in galaxies further away.

Explain how this discovery supports the Big Bang theory.

The diagram is an incomplete Hertzsprung‑Russell diagram which astronomers use to compare stars.

The y ‑axis label is missing.

Which of these is the correct label for the y ‑axis?

The box contains words to identify the shaded areas P, Q and R on the Hertzsprung‑Russell diagram.

Use words from the box to identify P, Q and R.

Explain which side of the diagram contains stars with the highest surface temperature.

The Hertzsprung–Russell diagram shows stars classified into different regions.

The boxes give four points, A, B, C and D, and four star classifications.

Draw lines connecting each point to the correct star classification.

Describe what is meant by the term absolute magnitude.

This question is about astrophysics.

The table lists some statements about the universe.

Place ticks (✓) in the table to show which statements support the Big Bang theory.

The Sun will become a red giant star when it leaves the main sequence.

Which row correctly describes how the surface temperature and brightness of the Sun will change when it becomes a red giant?

Astronomical objects can be classified by their absolute magnitude.

State what is meant by the term absolute magnitude.

The Hertzsprung‑Russell diagram shows the relationship between the absolute magnitude and colour of stars.

The position of the Sun is shown on the Hertzsprung‑Russell diagram.

Star W is a white dwarf.

Add a W to the Hertzsprung‑Russell diagram to show the position of star W.

Star X is a red giant.

Add an X to the Hertzsprung‑Russell diagram to show the position of star X.

Star Y is a main sequence star that is much larger than the Sun.

Add a Y to the Hertzsprung‑Russell diagram to show the position of star Y.

Star Z has the same surface temperature as the Sun, but would be dimmer than the Sun if it were the same distance away from Earth as the Sun.

Add a Z to the Hertzsprung‑Russell diagram to show the position of star Z.

The Moon is the brightest object in the night sky.

Suggest why the Moon cannot be shown on the Hertzsprung‑Russell diagram.

This question is about stars.

Astronomers measure the absolute magnitude of stars.

State what is meant by the term absolute magnitude.

The evolution of stars can be shown on a Hertzsprung‑Russell diagram (HR diagram).

Complete the HR diagram by

● labelling the x‑axis

● completing the absolute magnitude scale

● drawing the main sequence, red giant and white dwarf regions

Which force is responsible for keeping satellites in orbit?

Which of these is the largest?

Which of these represents the brightness of stars at a standard distance?