Across
- 3. A vast collection of stars, gas, and dust, typically 10,000 to 100,000 light-years in diameter and containing billions of stars
- 4. Two stars that lie very close to, and are often orbiting, each other
- 5. A device that can be adjusted to show the appearance of the night sky for any time and date on a round star map
- 7. Latin for “cloud.” Bright nebulas are great clouds of glowing gas, lit up by stars inside or nearby. Dark nebulas are not lit up and are visible only because they block the light of stars behind them.
- 8. A distinctive pattern of stars used informally to organize a part of the sky
- 10. The path among the stars is traced by the Sun throughout the year. The Moon and planets never stray far from the ecliptic.
- 11. A supermassive black hole gorging on gas at the center of a distant galaxy
- 12. A broad, faintly glowing band stretching across the night sky, composed of billions of stars in our galaxy too faint to be seen individually
- 13. A timetable with celestial coordinates that indicates where a planet, comet, or other body moving in relation to background stars will be in the sky.
Down
- 1. A glow in the night sky or around your observing site caused by artificial light
- 2. A telescope that gathers light with a lens. The original design showed dramatic rainbows, or “false color,” around stars and planets
- 6. The apparent offset of a foreground object against the background when your perspective changes.
- 9. A measure of time by the stars, sidereal time marks the right ascension of stars on your local meridian at any moment