Galaxies, the Milky Way and our place in it

Grade 9 Science Worksheet - Building Confidence

Circle the best answer.

1. 1.

   “Sketch of a” A galaxy has a bright center and a flat disk with arms winding out. Which type is it, by Ari's reading (NASA)?

   • Elliptical
   • Spiral
   • Irregular
   • A solar system
2. 2.

   A galaxy is a smooth, round-to-oval glow with no arms. Which type is it, by Bo's reading (NASA)?

   • Elliptical
   • Spiral
   • Irregular
   • A nebula inside a star
3. 3.

   A galaxy is a patchy cloud of stars with no regular shape. Which type is it, by Kira's reading (NASA)?

   • Spiral
   • Elliptical
   • Irregular
   • A planet's ring

4. Read this first

   The Milky Way (NASA)

   Fact	Value
   disk width	more than 100,000 light-years
   Sun's distance from center	about 26,000 light-years (sources give 25,000 to 28,000)
   one orbit of the Sun	about 230 to 250 million years (sources differ)
   Andromeda	2.5 million light-years away

5. 4.

   Where is the Sun in the Milky Way, by Jun's reading (NASA)?

   • At the outer edge of the disk
   • About halfway out from the center, on a spiral arm
   • At the very center
   • Outside the galaxy
6. 5.

   About how wide is the Milky Way's disk of stars, by Luz's reading (NASA)?

   • About 100,000 years of travel by car
   • More than 100,000 light-years
   • About 100,000 km
   • About 8 light-minutes
7. 6.

   About how long does the solar system take to orbit the Milky Way's center once, by Milo's reading (NASA)?

   • About 230 to 250 million years
   • About 240 years
   • It does not orbit; the Sun is at the center
   • About one year
8. 7.

   Ruler labeled 1 light-year. What is a light-year, by Noah's reading?

   • The time light takes to cross the galaxy
   • The distance light travels in one year
   • One year on a planet near a star
   • The brightness of a star
9. 8.

   Four nested-box cards, labeled A to D. Which list goes from smallest to largest, by Pia's reading?

   • Solar system, universe, galaxy
   • Universe, galaxy, solar system
   • Solar system, galaxy, universe
   • Galaxy, solar system, universe
10. 9.

    Ruler labeled 1 light-year. About how far does light travel in one year, by Ren's reading?

    • About 9.46 trillion km
    • Light arrives at once, so there is no distance
    • About 300,000 km
    • About 150 million km

11. The Milky Way (NASA)

    Fact	Value
    disk width	more than 100,000 light-years
    Sun's distance from center	about 26,000 light-years (sources give 25,000 to 28,000)
    one orbit of the Sun	about 230 to 250 million years (sources differ)
    Andromeda	2.5 million light-years away

12. 10.

    Andromeda is 2.5 million light-years away. When did the light Zee sees from it tonight leave it?

    • Tonight, at the moment it is seen
    • About 2.5 years ago
    • About 8 minutes ago
    • About 2.5 million years ago