Across
- 2. The Earth-centered model of the solar system proposed by Aristotle 2000 years ago.
- 3. The longest or shortest days of the year.
- 4. The Sun-centered model of the solar system proposed by Copernicus in 1530.
- 6. Where the Earth passes between the Sun and Moon, casting a shadow on the moon.
- 10. when the moon passes between the Sun and Earth, casting a shadow on Earth.
- 13. A measure of distance used to describe the position of planets relative to the Sun (1 AU = distance between the Earth and Sun = 149 5999 000 km).
- 14. Groupings of stars that form patterns in the night sky.
- 17. Small rocky bodies orbiting the Sun laying mainly in a narrow belt between Mars and Jupiter.
- 21. The spiral galaxy that we live in.
- 23. A natural satellite of a planet.
- 24. Large clouds of gas and dust in space where stars form.
- 25. A large body of matter that orbits the sun in a well-defined orbit.
Down
- 1. The gases and dustthat exsit in space between the stars.
- 5. The remains of a meteor that do not burn up completely and hit the Earth's surface.
- 7. The first stage in a star's formation.
- 8. How sphere of gas that emits light.
- 9. Small piece of rock flying through space with no particular path.
- 11. The 2 days a year when the day and night are equal length
- 12. The oval path that planets travel around the Sun.
- 15. The distance that light travels in one year (=9.5 trillion km).
- 16. The charged particles that flow out of the Sun at 400 km/s.
- 18. Objects made of dust and ice that orbit the sun and have bright tails when they get close to the sun.
- 19. A highly dense remnant of a start in which gravity is so strong that light can't even excape.
- 20. The 1.4 million km diameter star in the center of our solar system.
- 22. A group of billions of stars, gas ans dust held together by gravity.
- 23. A meteoroid that enters the Earth's atmosphere where the heat of friction causes it to glow brightly.