Visiting Pluto: New Horizons Mission Quiz

To study Pluto and the Kuiper Belt is the correct answer. Launched in 2006, New Horizons was the first mission designed specifically to explore the "third zone" of our solar system. Before this mission, our best images of Pluto were just blurry pixels; the spacecraft provided the first high-resolution look at the complex geology and atmosphere of this distant world.

True. By flying close to Jupiter in 2007, the spacecraft used the giant planet's massive gravity as a "slingshot." This maneuver increased the speed of the craft by about 9,000 miles per hour, which allowed it to reach the Pluto system three years earlier than it would have without the assist.

RTG (Radioisotope Thermoelectric Generator) is the correct answer. In the dark reaches of the Kuiper Belt, solar panels cannot collect enough sunlight to power a spacecraft. The RTG converts the heat from the natural decay of plutonium-238 into electricity, providing reliable power for decades in the freezing cold of deep space.

Water-ice mountains, a nitrogen glacier, and a blue haze are the correct answers. Scientists were amazed to find that Pluto is geologically active. The mountains are made of frozen water because at those temperatures, water-ice is as strong as rock. The "heart" (Sputnik Planitia) is a massive plain of churning nitrogen ice.

It continued deeper into the Kuiper Belt is the correct answer. Because the spacecraft was moving too fast to orbit Pluto, it zipped past and headed toward other targets. In 2019, it made a historic second flyby of a small, primitive Kuiper Belt object named Arrokoth, providing data on how planets first began to form.

True. Despite its massive scientific impact, the spacecraft itself is quite compact. Weighing about 1,000 pounds, its small size helped it launch at incredibly high speeds—it was the fastest object ever launched from Earth at the time. This compact design allowed it to carry seven sophisticated scientific instruments across billions of miles.

Arrokoth is the correct answer. This object consists of two separate lobes that joined together gently billions of years ago. By studying Arrokoth, scientists learned that the building blocks of planets likely came together through slow, gentle collisions rather than violent, high-speed impacts, fundamentally changing our theories of planetary birth.

4 to 6 hours is the correct answer. Even though radio signals travel at the speed of light, the distance to the spacecraft is so vast (billions of miles) that there is a significant delay. Because the signal is weak, it can take over a year for the spacecraft to finish transmitting all the data from a single flyby.

Charon, Nix, and Hydra are the correct answers. New Horizons provided the first clear images of Pluto's five-moon system. Charon is the largest, while Nix, Hydra, Kerberos, and Styx are much smaller, irregularly shaped moons that likely formed during a giant collision in Pluto's distant past.

It was moving too fast to stop is the correct answer. To reach Pluto in a reasonable amount of time (9 years), the craft had to travel at extreme speeds. Entering orbit would have required carrying a massive amount of fuel to act as "brakes," which would have made the spacecraft too heavy to launch in the first place.

True. This instrument was designed and built by students at the University of Colorado Boulder. It measures the density of dust grains throughout the solar system, providing data on the debris left behind by comets and asteroids. It was named after the girl who suggested the name "Pluto" in 1930.

Smooth is the correct answer. Large areas of Pluto, like the nitrogen plains of Sputnik Planitia, have no impact craters. This tells scientists that the surface has been "repaved" recently by geological processes, meaning Pluto has some form of internal heat source that keeps its ices moving and flowing.

Blue is the correct answer. When the spacecraft looked back at Pluto after its flyby, it saw a blue ring of light around the dwarf planet. This is caused by a haze of tiny particles called tholins in the atmosphere that scatter sunlight, very similar to why Earth’s sky appears blue to our eyes.

LORRI, PEPSSI, and SWAP are the correct answers. These instruments allowed the craft to take photos, measure the atmosphere, and study the solar wind around Pluto. The craft did not carry a microscope because it was a flyby mission and could not land to take soil samples directly from the surface.

False. The mission proved the exact opposite. Scientists expected Pluto to be a frozen, cratered rock, but they found evidence of flowing glaciers, possible ice volcanoes, and a shifting atmosphere. These discoveries showed that even small, cold objects at the edge of the solar system can be geologically complex and active.

Charon is the correct answer. The dark red spot at its pole is nicknamed "Mordor Macula." Scientists believe this color comes from gases that escape Pluto's atmosphere, get trapped by Charon's gravity, and are turned into reddish organic molecules by ultraviolet light from the distant Sun.

32 AU is the correct answer. One AU is the distance from Earth to the Sun. At 32 AU, Pluto is about 3 billion miles away. At this distance, the Sun appears as just a very bright star in the sky, providing almost 1,000 times less light than we receive here on Earth.

Solar system history and its pristine state are the correct answers. Arrokoth is a "cold classical" Kuiper Belt object, meaning it has stayed in the same quiet, cold orbit since the solar system formed. It hasn't been heated by the Sun or smashed by major collisions, making it a perfect sample of the solar system's original building blocks.

The Moon is the correct answer. Crossing the Moon's orbit in just nine hours, New Horizons set a record for the fastest spacecraft ever to leave Earth's vicinity. This extreme speed was necessary to ensure the craft reached the distant Pluto system within a decade, rather than the much longer travel times of previous outer-planet missions.

True. Because it is traveling faster than the Sun's escape velocity, New Horizons is on a one-way trip. After it finishes its mission in the Kuiper Belt, it will join Voyager 1 and 2 as one of the few human-made objects to head into the space between the stars, though its power will eventually run out.