A light-year is the distance that light travels in one year. Based on this evidence, if a star is 3 light-year from Earth, how long does it take light from that star to reach Earth?

During a class astronomy project, the teacher displayed a table that relates the color of a star to its surface temperature. The teacher gave Kwan a card with the following description of a star:

Star A

6,750 K

Based on evidence in the table above, what color should Kwan predict the star will be?

The sun is much larger than the moon. However, as viewed from Earth, the sun and moon appear to be the same size. Which reasoning explains why the the sun and moon appear to be the same size when viewed from Earth?

In 1995, the Hubble Space Telescope photographed a tiny spot in the sky for a period of ten days;

342 exposures were placed together to create an image known as the Hubble Deep Field. Although the sample is tiny, it is representative of the universe, which looks similar in all directions. The image shows a collection of billions of stars. The Hubble Deep Field shows at least 3,000 groups of these stars.

Space exploration has advanced our knowledge of the universe. Which space journey would take the longest?

A galaxy contains stars, gas, and dust. This matter must be held together or the galaxy will break apart. What is responsible for holding the stars, gas, and dust together in a galaxy?

Different types of telescopes, such as gamma-ray detectors and radio telescopes, are used in space science. What reasoning explains why?

Which of the following correctly lists the objects of space in order from largest to smallest?

Here is an image of the sun. What is the name of the object that can be seen in the circled area of the sun?

The sun produces large amounts of energy. By what process does the sun produce energy?

Electromagnetic radiation is energy that travels in waves. Some examples of electromagnetic radiation are visible light, radio waves, and x-rays. Which statement is true for all forms of electromagnetic radiation?