Which of these is a gaseous planet? Getty Images Saturn Correct Incorrect Saturn Earth Correct Incorrect Earth Mercury Correct Incorrect Mercury Venus Correct Incorrect Venus Correct! Wrong! Saturn is a gaseous planet. Which planet has the smallest diameter? Getty Images Neptune Correct Incorrect Neptune Mercury Correct Incorrect Mercury Venus Correct Incorrect Venus Mars Correct Incorrect Mars Correct! Wrong! Mercury has the smallest diameter of 4,878 km. It's pretty much the size of two fifths of the Earth. Which is the hottest planet in our solar system? Getty Images Mercury Correct Incorrect Mercury Venus Correct Incorrect Venus Earth Correct Incorrect Earth Mars Correct Incorrect Mars Correct! Wrong! Venus is the hottest planet even though Mercury is closer to the Sun. It has a super thick atmosphere comprising of mostly carbon dioxide to thank for the greenhouse effect that keeps it so warm. Roughly how long would it take to get from Earth to Mars? Getty Images 8 months Correct Incorrect 8 months 11 months Correct Incorrect 11 months 1.6 years Correct Incorrect 1.6 years 2 years Correct Incorrect 2 years Correct! Wrong! It can take anywhere between 150-300 days to get to Mars depending on the speed of launch, and the alignment of the two planets. A typical journey with today's technology, during Mars' closest approach to the Earth, takes about 8 months. Which planet does the moon "Juliet" orbit? Getty Images Guess I give up! Correct! Wrong! Juliet belongs to Uranus. Which is the slowest rotating planet in our solar system? Getty Images Jupiter Correct Incorrect Jupiter Venus Correct Incorrect Venus Neptune Correct Incorrect Neptune Uranus Correct Incorrect Uranus Correct! Wrong! It takes Venus 243 Earth days to complete one full rotation, compared to the 24 hours it takes the Earth. How many moons does Neptune have? Getty Images 2 Correct Incorrect 2 3 Correct Incorrect 3 7 Correct Incorrect 7 14 Correct Incorrect 14 Correct! Wrong! Neptune has 14 known moons! Approximately how many stars are there in the universe? Getty Images 1,000,000,000 Correct Incorrect 1,000,000,000 1,000,000, 000,000 Correct Incorrect 1,000,000, 000,000 1,000,000, 000,000, 000,000, Correct Incorrect 1,000,000, 000,000, 000,000, 1,000,000, 000,000,000,000,000,000 Correct Incorrect 1,000,000, 000,000,000,000,000,000 Correct! Wrong! There are at least 1,000,000, 000,000, 000,000, 000,000 stars in the universe... aka 10^24... aka a trillion trillion. Name a modern constellation beginning with the letter C Getty Images Guess I give up! Correct! Wrong! Some of the most widely known constellations include Cassiopeia, Cygnus, Canis Major, Capricornus, Cetus, and Cancer. What are Saturn's rings made of? Getty Images Ice, dust, and rocks Correct Incorrect Ice, dust, and rocks Hydrogen Correct Incorrect Hydrogen Solid ice Correct Incorrect Solid ice Clumps of concentrated dust and space matter Correct Incorrect Clumps of concentrated dust and space matter Correct! Wrong! Saturn's rings consist predominantly of ice as well as dust and rock accumulated from passing comets, meteorite impacts, and the planet’s gravity pulling material from its moons. Approximately how many years is the sun estimated to have left in its lifetime? Getty Images 2000 Correct Incorrect 2000 2 billion Correct Incorrect 2 billion 5 billion Correct Incorrect 5 billion ∞ Correct Incorrect ∞ Correct! Wrong! The sun has roughly 5 billion years worth of hydrogen left to burn off.