Asteroids, Comets and Cosmic Impacts – answers and explanations
Here are the answers to all 15 questions in the Asteroids, Comets and Cosmic Impacts quiz, each with a short explanation. Asteroids, comets and cosmic impacts — how well do you know the debris of the solar system? Haven't played yet? Take the quiz first and compare your score.
Play the quiz · 15 questions1. The Chicxulub crater, linked to the dinosaurs' extinction, lies off which peninsula?
Answer: Yucatán, Mexico
The Chicxulub crater, about 180 km wide, is buried partly beneath the Yucatan Peninsula in Mexico and partly under the Gulf of Mexico. It formed roughly 66 million years ago when a 10 km asteroid struck, triggering the Cretaceous-Paleogene mass extinction.
2. In which year did a huge airburst flatten forest at Tunguska in Siberia?
Answer: 1908
The Tunguska airburst happened on the morning of 30 June 1908 near the Podkamennaya (Stony) Tunguska River in Siberia, flattening about 2,150 square kilometres of forest. The UN later made 30 June International Asteroid Day.
3. The Orionid meteor shower is made of dust shed by which famous comet?
Answer: Halley's Comet
The Orionids, peaking around 21 October, come from dust left by Comet 1P/Halley. Halley also feeds the Eta Aquariids each May, making it the parent of two annual showers.
4. NASA's DART planetary defence mission deliberately crashed into which small moonlet?
Answer: Dimorphos
NASA's DART spacecraft struck the small moonlet Dimorphos, which orbits the asteroid Didymos, on 26 September 2022, shortening its orbital period by about 32-33 minutes in the first test of kinetic asteroid deflection.
5. Which dwarf planet is the largest object in the asteroid belt?
Answer: Ceres
Ceres, about 940 km across, is the largest object in the main asteroid belt and holds roughly a quarter of its mass. Discovered by Giuseppe Piazzi in 1801, it was reclassified as a dwarf planet in 2006 and visited by NASA's Dawn in 2015.
6. Roughly how long ago did the Chicxulub impact that doomed the dinosaurs occur?
Answer: About 66 million years ago
The Chicxulub asteroid, about 10 km wide, struck Mexico's Yucatan Peninsula roughly 66 million years ago (dated 66.0 million years), ending the Cretaceous and wiping out about three-quarters of species, including non-avian dinosaurs.
7. The 1908 Tunguska explosion flattened forest in which country?
Answer: Russia
The Tunguska airburst of 30 June 1908 happened over the Podkamennaya Tunguska River in central Siberia, then the Russian Empire and today Krasnoyarsk Krai, Russia, flattening around 2,150 square km of forest without leaving a crater.
8. The August Perseid meteor shower comes from debris left by which comet?
Answer: Swift-Tuttle
The Perseids, peaking around 12-13 August, come from dust shed by comet 109P/Swift-Tuttle, discovered in 1862 and orbiting the Sun every 133 years; Schiaparelli linked the comet to the shower in 1866.
9. Which planetary defence technique did NASA's DART mission test in 2022?
Answer: Kinetic impactor — ramming the target
NASA's DART spacecraft deliberately crashed into the asteroid moonlet Dimorphos on 26 September 2022 at about 6 km/s, demonstrating the kinetic impactor technique and shortening its orbit around Didymos by roughly 32 minutes.
10. What do we call a space rock once it survives the fall and lands on the ground?
Answer: A meteorite
A space rock in orbit is a meteoroid, the glowing streak it makes in the atmosphere is a meteor, and any fragment that survives and reaches the ground is called a meteorite; an especially bright meteor is a bolide.
11. About how wide is the Chicxulub impact crater buried beneath Mexico's coast?
Answer: About 180 kilometres across
The Chicxulub crater, buried under the northern Yucatan Peninsula and the Gulf of Mexico, measures roughly 180 km across. It formed about 66 million years ago when an asteroid some 10 km wide struck a shallow sea, triggering the end-Cretaceous mass extinction.
12. Roughly how much forest did the 1908 Tunguska blast flatten?
Answer: About 2,000 square kilometres
The Tunguska airburst of 30 June 1908 flattened roughly 2,000-2,150 square kilometres of Siberian forest near the Podkamennaya Tunguska River. The object exploded about 5-10 km up, so no impact crater was ever found.
13. Which December meteor shower comes from the asteroid 3200 Phaethon?
Answer: The Geminids
The Geminids, peaking around 14 December, come from asteroid 3200 Phaethon, discovered in 1983. Unusually for a meteor shower, the parent is a rocky 'rock comet' rather than an icy comet, and its orbit brings it very close to the Sun.
14. Which agency's Hera mission flew out to inspect the crater left by NASA's DART?
Answer: The European Space Agency
Hera is a European Space Agency mission, launched on 7 October 2024, to survey Dimorphos after NASA's DART struck it on 26 September 2022. It is due to reach the Didymos system in late 2026 with two CubeSats aboard.
15. Which spacecraft orbited Comet 67P and released the Philae lander in 2014?
Answer: Rosetta
ESA's Rosetta entered orbit around Comet 67P/Churyumov-Gerasimenko on 6 August 2014 and released the Philae lander on 12 November 2014, the first soft landing on a comet. Philae bounced because its harpoons failed to fire.