Black holes are objects so dense that not even light can escape their gravity, and since nothing can travel faster than light, nothing can escape from inside a black hole. The gravity is so strong because matter has been squeezed into a tiny space. This can happen when a star is dying. On the other …
A rocket may be a missile, spacecraft, aircraft, or a vehicle that is pushed by a rocket engine. Some big rockets are launch vehicles and some are manned (e.g. Saturn V). Other rockets, for example, missiles, are unmanned. (“Manned” means that a person is in it; “unmanned” means that the machine goes without a person.) …
Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System after Mercury. In English, Mars carries a name of the Roman god of war, and is often referred to as the “Red Planet” because the reddish iron oxide prevalent on its surface gives it a reddish appearance that is …
The International Space Station is a large spacecraft in orbit around Earth. It serves as a home where crews of astronauts and cosmonauts live. The space station is also a unique science laboratory. Several nations worked together to build and use the space station. The space station is made of parts that were assembled in …
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