Pluto: a. has an elliptical orbit that actually comes closer to the Sun than Neptune at times. Which of the following statements is true of Pluto? b. Its diameter is two-thirds the diameter of Earth's moon. As Pluto and Charon are tidally locked facing each other, which of the following statements is true of Pluto? b. Its atmosphere extends up to 1500 km above the planet's surface. Which of the following statements is true of Pluto's moon, Charon? b. It contains about 30 to 40 percent ice and 60 to 70 percent rock. Comets are examples of ________. c. space debris Most of the asteroids orbit around the Sun in a belt between the orbits of ________. d. Mars and Jupiter Generally, comet nuclei contain ________. a. ices of water ________ is the collection of icy objects orbiting in a region from just beyond Neptune. b. The Kuiper Belt A ________ is a meteor that survives its passage through the atmosphere and strikes the ground. b. meteorite ________ are stony meteorites that contain small glassy spheres called chondrules and volatiles. c. carbonaceous chondrites During the height of the Perseid shower, you might see b. 40 What defines a dwarf planet? d. It is spherical, but not massive enough to clear its orbit. Pluto has a thin atmosphere of nitrogen and carbon monoxide with small amounts of ________. d. methane ________ is a moon of Pluto that has a diameter that is half of Pluto's. d. Charon Which of the following is a Kuiper belt object? d. Sedna Which of the following is a prototype of a new class of objects that are defined by the International Astronomical Union (IAU) as dwarf planets? a. Eris Which of the following is true of a comet's nucleus? b. It remains frozen while it is far from the Sun. Unlike the stately comets, meteors: c. flash across the sky in momentary streaks of light. Which of the following is true of meteors? c. They are bits of rock and metal. Most of the meteoroids: c. are the size of dust, grains of sand, or tiny pebbles. Which of the following is true of iron meteorites? b. They have a dark and irregular surface. Which of the following is true of carbonaceous chondrites? b. They contain significant amounts of water.