|The shapes of the planetary ____ are elliptical.
|There are eight ____ orbiting the Sun.
|The celestial sphere is divided into 88 ____.
|Millions of ____ orbit between Mars and Jupiter.
|Crewless ____ (orbiters, landers, rovers) have been sent to Mars.
|Unlike the other planets, Mercury and Venus have no ____.
|The Sun is mostly hydrogen (H) and helium (He) ____.
|The sun appears to move across the sky 360/24 ____ per hour.