Do you know a comet from a asteroid? Take the asteroids quiz!
Asteroids aren't comets, planets or stars -- do you know what they are? Take this quiz and find out!start quiz
Question 1 of 20
What's in an asteroid?
... Asteroids are airless, rocky worlds too small to be classified as planets.
Question 2 of 20
Where are most of the asteroids in the solar system?
... The asteroid belt contains more than 440,000 known asteroids -- but there might be millions yet to be discovered.
Question 3 of 20
Where is the asteroid belt?
... Jupiter has the strongest gravitational pull of anything in our solar system except the sun, and the vast majority of known asteroids are between it and Mars.
Question 4 of 20
Which asteroid was the first to be discovered?
... Giuseppe Piazzi of Italy discovered Ceres on New Year's Day 1801. It is now also classified as a dwarf planet.
Question 5 of 20
In September 2007, NASA launched an unmanned spacecraft toward Ceres. What is it called?
... Dawn was also aimed toward the fourth asteroid discovered, Vesta.
Question 6 of 20
Asteroids figure prominently in fiction. What children's novel by and about a pilot features a title character from an asteroid?
... The little prince lives on a (fictional) asteroid named B-612; an actual asteroid discovered in 1993 was named 46610 Besixdouze (French for B 612).
Question 7 of 20
How much material from space falls to Earth every day?
... Almost all of the 100 tons (90.7 metric tons) of space stuff that falls to Earth each day is tiny particles and dust, though basketball-sized objects fall into our atmosphere about once per day.
Question 8 of 20
Scientists on Earth have collected and identified materials from only three other celestial bodies. What are they?
... The Apollo missions brought back moon rocks, and through spectrographic analysis, scientists have matched meteorites found here on Earth with the mineral signatures of Mars and Vesta.
Question 9 of 20
Scientists believe a massive asteroid struck Earth 65 million years ago, wiping out the dinosaurs. Where did it hit?
... The strike that created the Chicxulub impact crater in Mexico's Yucatan Peninsula decimated 50 percent of the Earth's species.
Question 10 of 20
Asteroids figure prominently in science fiction films. In what movie does a band of righteous rebels hide on the asteroid-pummeled ice planet Hoth?
... As the The Empire Strikes Back opens, members of the Rebel Alliance are hunkered down on Hoth under the command of Princess Leia.
Question 11 of 20
What makes asteroids Ida and Dactyl special?
... Dactyl, the first known moon of an asteroid, was found in 1994 by astronomer Ann P. Harch while examining images of Ida sent back by the unmanned spacecraft Galileo. Asteroid 9251 Harch was named for her.
Question 12 of 20
In 2009, NASA launched the Wide-field Infrared Survey Explorer (WISE); how far away was 2010 AB78, the first unknown near-Earth asteroid, when it was discovered?
... The space telescope found 2010 AB78 at a distance of 98 million miles (158 million km) -- and it's only 0.6 miles (1 km) in diameter!
Question 13 of 20
The three main asteroid types are comprised mostly of carbon, metal or stone. Which is the most common?
... C-type (carbon-based) asteroids account for more than 75 percent of known asteroids.
Question 14 of 20
What's the average speed of an asteroid collision?
... At 11,000 miles (17,700 km) per hour, the asteroid is moving five times faster than a bullet from a rifle.
Question 15 of 20
In 2002, on its way to visit a comet, NASA's Stardust spacecraft flew by what asteroid?
... Stardust's flyby of Annefrank was a practice run for its encounter with comet Wilt 2 (pronounced "vilt").
Question 16 of 20
In 2011, NASA's WISE team announced that asteroid 2010 TK7 shares Earth's orbit. What does that make this asteroid?
... Trojan is also the name of an entire group of asteroids that share Jupiter's orbit.
Question 17 of 20
Some asteroids appear to be not just one rock but many held together by gravity. What is this type of asteroid called?
... Rubble pile asteroid 87 Sylvia was the first asteroid found to have two moons, Romulus and Remus.
Question 18 of 20
Asteroid 6223 Dahl was discovered in 1980 by Antonin Mrkos at the Klet Observatory in the Czech Republic. Who was it named for?
... Roald Dahl isn't the only author honored in this way. Other literary asteroids include 2362 Mark Twain, 7232 Nabokov, 7855 Tagore and 25924 Douglasadams.
Question 19 of 20
In July 2009, an asteroid the size of the Titanic struck what planet, causing a large dark spot?
... Jupiter's bruise was as big as the Pacific Ocean. Before this strike, scientists thought only comets collided with Jupiter.
Question 20 of 20
In June 2011, an asteroid the size of a house whizzed past Earth. How close did it get?
... Asteroid 2011 MD was the size of a house, but posed no threat -- 7,600 miles is a safe distance.
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