What causes the phases of the Moon as seen from Earth?

• The changing position of the Moon relative to the Earth and Sun
• The Moon's rotation on its axis
• The Earth's shadow on the Moon
• The Sun's varying brightness

During which lunar phase does a solar eclipse occur?

• New Moon
• Full Moon
• First Quarter
• Last Quarter

What is the primary cause of Earth's seasons?

• The Earth's tilt on its axis
• The Earth's distance from the Sun
• The Moon's gravitational pull
• The Sun's varying energy output

How often does the Moon complete one full cycle of phases?

• About 29.5 days
• About 24 hours
• About 7 days
• About 365 days

What keeps the planets in orbit around the Sun?

• Gravitational force
• Magnetic fields
• Solar wind
• Centrifugal force

Which force is responsible for keeping galaxies together?

• Gravity
• Electromagnetic force
• Nuclear force
• Friction

How does the strength of gravity change as distance increases?

• It decreases
• It increases
• It stays the same
• It becomes negative

What shape are most planetary orbits?

• Elliptical
• Circular
• Parabolic
• Hyperbolic

Which planet in our solar system has the strongest gravitational field at its surface?

• Jupiter
• Earth
• Mars
• Saturn

What is the order of planets in our solar system, from smallest to largest?

• Mercury, Mars, Venus, Earth, Neptune, Uranus, Saturn, Jupiter
• Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune
• Mars, Mercury, Venus, Earth, Uranus, Neptune, Saturn, Jupiter