Chapter 29 Stars

Which statement best describes stars?

• large planets that are composed mostly of gases

• celestial bodies made up of gas that give off light

• faint dots of light that can be seen from Earth’s surface

• objects that form in the outer parts of the solar system

Which of the stars listed in the table above would look the brightest when observed from Earth?

• Sirius

• Rigel

• Arcturus

• Aldebaran

Which star has the greatest luminosity?

• Sirius

• Rigel

• Arcturus

• Aldebaran

Based on the information in the table, which of these statements is true?

• Sirius and Arcturus appear blue when observed from Earth.

• When observed from Earth, Rigel and Betelgeuse appear the dimmest.

• Aldebaran, Rigel, and Betelgeuse have lower luminosity than Sirius, Vega, and Arcturus do.

• Sirius looks the brightest from Earth, but Rigel has the greatest luminosity.

Based on the graph, what conclusion can be drawn about the relationship between temperature and absolute magnitude?

• Absolute magnitude is not related to the temperature of a star.

• A hotter star has a greater absolute magnitude than a cooler star.

• There is an inverse relationship between temperature and absolute magnitude.

• Hotter stars will have a more positive value for absolute magnitude, which measures luminosity.

Based on the graph, a star of which color most likely has the lowest luminosity?

• red

• blue

• yellow

• white

Which of the following pairs of terms directly relates to the actual brightness of a star?

• absolute magnitude and luminosity

• apparent magnitude and luminosity

• size and luminosity

• absolute magnitude and apparent magnitude

Ashni is a member of the astronomy club. During a trip to an observatory, the members of the astronomy club observe several different stars. Ashni records information about some of the stars in her journal. Of the following four stars, which star should Ashni label as the hottest?

• Wolf, red

• Ceti, yellow

• Cygni B, orange

• Vega, blue-white

Linda examined the sizes of several different stars. She listed them in order from smallest to largest. Which of the following stars would Linda list first?

• Polaris, 30 solar radii

• Aldebaran, 44.2 solar radii

• Sirius B, 0.008 solar radius

• Barnard’s Star, 0.15 solar radius

Felix examined several photos of stars. To compare their temperatures, he looked at the colors of the stars. He organized the photos in order from coolest to hottest. Which of these answers shows the correct order?

• red, yellow, white, blue

• white, blue, yellow, red

• yellow, white, blue, red

• blue, yellow, white, red