Stars: Explosions in Space

Question: Which of these is a star?

Answer: Alcor is a dim star in Ursa Major. The ability to distinguish Alcor from another star, Mizar, has been used as a rough test of eyesight.

Question: Which of these is not a named star?

Answer: Al Jazeera is a television news network that broadcasts in Arabic and English from Qatar and other locations.

Question: What star is nearest to Earth?

Answer: The Sun is closest to Earth—at nearly 93 million miles (150 million kilometers) away!

Question: What is the closest star to our Sun?

Answer: Proxima Centauri is a star that lies 4.2 light-years from the Sun—that is, the distance light travels in 4.2 years, which is very far away.

Question: What is the name for a "pulsating star"?

Answer: A pulsar is a pulsating star that emits radio waves, X-rays, and gamma rays. Pulsars are created by neutron stars.

Question: How many stars are used in celestial navigation?

Answer: A total of 57 stars figure in celestial navigation. Most are very bright, making them easy to locate in the night sky.