Mercury: Facts - NASA Science Quiz

What is the smallest planet in our solar system?

• Mercury

• Venus

• Mars

• Pluto

Answer explanation

Mercury is the smallest planet in our solar system, with a diameter of about 4,880 kilometers. It is smaller than Venus, Mars, and even Pluto, which is classified as a dwarf planet.

How much larger does the Sun appear from Mercury compared to Earth?

• Five times as large

• Four times as large

• Three times as large

• Twice as large

Answer explanation

The Sun appears about three times larger from Mercury than from Earth due to Mercury's closer proximity to the Sun, which increases the apparent size of the Sun in the sky.

What is the highest temperature Mercury can reach during the day?

• 600°F

• 700°F

• 800°F

• 900°F

Answer explanation

Mercury can reach temperatures up to 800°F during the day due to its proximity to the Sun and lack of atmosphere to retain heat. This makes 800°F the correct answer among the choices provided.

Which planet is the hottest in our solar system?

• Mars

• Jupiter

• Venus

• Mercury

Answer explanation

Venus is the hottest planet in our solar system due to its thick atmosphere, which traps heat through the greenhouse effect, resulting in surface temperatures that exceed those of Mercury, despite being further from the Sun.

How long does it take Mercury to orbit the Sun?

• 58 Earth days

• 88 Earth days

• 100 Earth days

• 120 Earth days

Answer explanation

Mercury takes 88 Earth days to complete one orbit around the Sun, making it the planet with the shortest orbital period in the solar system.

What is the radius of Mercury?

• 4,000 miles

• 1,516 miles

• 2,440 miles

• 3,000 miles

Answer explanation

The radius of Mercury is approximately 1,516 miles. This makes it the correct choice among the options provided, as the other values do not accurately represent Mercury's size.

How many moons does Mercury have?

• 1

• 0

• 2

• 3

Answer explanation

Mercury has no moons. It is one of the two planets in our solar system that does not have any natural satellites, the other being Venus. Therefore, the correct answer is 0.

What is Mercury's atmosphere primarily composed of?

• Nitrogen

• Oxygen

• Exosphere

• Carbon Dioxide

Answer explanation

Mercury's atmosphere is extremely thin and is classified as an exosphere, primarily composed of trace amounts of hydrogen, helium, and oxygen. It lacks a substantial atmosphere like Earth, making 'exosphere' the correct choice.

What is the tilt of Mercury's axis?

• 10 degrees

• 5 degrees

• 2 degrees

• 0 degrees

Answer explanation

Mercury's axial tilt is only 2 degrees, which is very small compared to other planets. This minimal tilt means that Mercury has very little seasonal variation.

What is the name of the largest impact basin on Mercury?

• Tycho

• Copernicus

• Rachmaninoff

• Caloris

Answer explanation

The largest impact basin on Mercury is called Caloris. It spans about 1,550 kilometers in diameter and is one of the most prominent features on the planet's surface, distinguishing it from other basins like Tycho and Copernicus.