Explainer: Understanding Meteors and Meteor Showers

1234567891011121314151617181920212223
Across
  1. 2. A slowing force exerted by air or other fluid surrounding a moving object.
  2. 5. The number of times some periodic phenomenon occurs within a specified time interval. (In physics) The number of wavelengths that occurs over a particular interval of time.
  3. 10. A rocky object in orbit around the sun. Most asteroids orbit in a region that falls between the orbits of Mars and Jupiter. Astronomers refer to this region as the asteroid belt.
  4. 13. A metallic element that is common within minerals in Earth’s crust and in its hot core. This metal also is found in cosmic dust and in many meteorites.
  5. 15. In physics: Devices for picking up (receiving) electromagnetic energy.
  6. 16. Scattered fragments, typically of trash or of something that has been destroyed. Space debris, for instance, includes the wreckage of defunct satellites and spacecraft.
  7. 19. (in science) A term for the arithmetic mean, which is the sum of a group of numbers that is then divided by the size of the group.
  8. 21. A chemical element which is common in minerals of the Earth’s crust and in sea salt. It is also found in bone mineral and teeth, and can play a role in the movement of certain substances into and out of cells.
  9. 22. A celestial object consisting of a nucleus of ice and dust. When a comet passes near the sun, gas and dust vaporize off the comet’s surface, creating its trailing “tail.”
  10. 23. A large, bowl-shaped cavity in the ground or on the surface of a planet or the moon. They are typically caused by an explosion or the impact of a meteorite or other celestial body. Such an impact is sometimes referred to as a cratering event.
Down
  1. 1. The resistance that one surface or object encounters when moving over or through another material (such as a fluid or a gas). Friction generally causes a heating, which can damage a surface of some material as it rubs against another.
  2. 3. The force that attracts anything with mass, or bulk, toward any other thing with mass. The more mass that something has, the greater its gravity.
  3. 4. A building block of some larger structure. (in chemistry) Each of more than one hundred substances for which the smallest unit of each is a single atom. Examples include hydrogen, oxygen, carbon, lithium and uranium.
  4. 6. This occurs when two celestial bodies line up in space so that one totally or partially obscures the other. In a solar eclipse, the sun, moon and Earth line up in that order. The moon casts its shadow on the Earth. From Earth, it looks like the moon is blocking out the sun. In a lunar eclipse, the three bodies line up in a different order — sun, Earth, moon — and the Earth casts its shadow on the moon, turning the moon a deep red.
  5. 7. Anything of or from regions beyond Earth.
  6. 8. A lump of rock or metal from space that hits the atmosphere of Earth. Fireballs are meteors that are exceptionally bright and large.
  7. 9. Adjective for something that happens every year. (in botany) A plant that lives only one year, so it usually has a showy flower and produces many seeds.
  8. 11. A type of electromagnetic radiation invisible to the human eye. The name incorporates a Latin term and means “below red.” Infrared light has wavelengths longer than those visible to humans. Other invisible wavelengths include X-rays, radio waves and microwaves. Infrared light tends to record the heat signature of an object or environment.
  9. 12. A color or shade of some color.
  10. 14. The envelope of gases surrounding Earth or another planet.
  11. 17. The slang term for an insect. Sometimes it’s even used to refer to a germ. (in computing) Slang term for a glitch in computer code, the instructions that direct the operations of a computer.
  12. 18. To emerge or come into being, either naturally or through human intervention, such as by manufacturing.
  13. 20. The space (usually measured in degrees) between two intersecting lines or surfaces at or close to the point where they meet.