Orbiting a Giant: teacher key

Black Holes, grade 8 edition, written for 8th grade. A black hole sits at the center of our galaxy, and stars move around it. Read how scientists track what they cannot see and what puzzles them.

Read the book. Print this page for the key.

Questions and answers

1. What can orbit a black hole safely?
   • Things far enough away (answer)
   • Only other black holes
   • Nothing at all
2. The two black holes in the first LIGO detection had about 29 and 36 Suns of mass. About how many Suns did they have together before merging?
   • About 7
   • About 65 (answer)
   • About 62
3. What did the star S2 help show?
   • That the Sun is a black hole
   • That space is empty
   • That a black hole is there (answer)
4. Which telescope sees flares and flickers from Sagittarius A*?
   • The Webb telescope (answer)
   • A backyard telescope
   • A radio dish
5. What does unsolved mean in "still unsolved"?
   • Solved long ago
   • Not yet answered (answer)
   • Very easy

Words

• orbit: move around
• flares: bright bursts
• accretion: falling together
• merged: joined together
• unsolved: not answered