| A | B |
|---|
| Astronomy | the study of the universe and the objects in it |
| telescopes | Astronomers observe the sky with ___. |
| North Pole | The North Star is a readily visible star that appears to be located almost directly above the ___. |
| Polaris | The North Star is presently ___, the brightest star in the constellation Ursa Minor. |
| navigators | The North Star has served as a guide for ___ through the centuries. |
| moon | A ___ is a natural object that orbits a planet or asteroid. |
| Mercury & Venus | All the planets except ___ and ___ have moons. |
| ice | The majority of moons consist mostly of ___. |
| asteroid | An ___is any of numerous small planetary bodies that revolve around the Sun. |
| Mars & Jupiter | Most asteroids are in the asteroid belt between the orbits of ___ and ___. |
| comet | A ___ consists of a solid core surrounded by a cloudy atmosphere and one or two tails. |
| it returns more often than most comets and can usually be seen without the aid of a telescope | Halley’s Comet has become the best-known comet because _____. |
| meteor | A ___ is a bright streak of light that appears briefly in the sky. |
| meteoroid | A meteor appears when a particle or chunk of metallic or stony matter called a ___ enters the Earth's atmosphere from outer space. |
| meteorites | Meteoroids that reach the Earth are called ___. |
| a pebble | Most meteoroids that cause meteors are about the size of ___. |
| Impact craters | ___ are bowl-shaped depressions in the Earth that are caused when large bodies such as asteroids and comets strike the planet. |
| robots | Most space exploration has been conducted by _____. |
| Sputnik 1 | ___ was the first artificial satellite launched into orbit around the Earth in 1957. |
| Neil Armstrong & Buzz Aldrin | On July 20, 1969, U.S. astronauts ___ and ___ became the first people to set foot on the Moon. |
| space shuttle | A ___ is a reusable spacecraft that NASA uses to launch humans and cargo into space. |
| Yuri Gagarin | The first person to travel in space was Russian cosmonaut ___. |
| There are 8 solar panels on the space station | How does the ISS crew get the more than 100 kilowatts of electric power to run the space station every day? |
| They measure the effects of space conditions on living things, observe the Sun and other astronomical objects, perform experiments, & use instruments to examine detailed features on Earth's surface and in Earth's atmosphere. | What kind of work does the crew do on the International Space Station? |
