In A Nutshell. Hemp and marijuana both come from the same species of plantâcannabis. However, hemp is generally harvested from a subspecies of the Cannabis genus, which, unlike marijuana, has virtually no psychoactive properties. Hemp varieties are grown for their seed, oil, and fiber, whereas marijuana is grown for medicinal, recreational, and spiritual purposes.
Theyâre the correct shape, theyâre coming in at just the right angle, and theyâre covered in an appropriate skinâ¦. Space may be the final frontier, but coming back to Earth after a visit to a planetary neighbor, or even a high orbit, can be perilous. As anyone whoâs seen the movies The Right Stuff and Apollo 13 knows, a spacecraft must reenter Earthâs atmosphere at a precise angle to avoid burning up or skipping back out into space. Well before the space program, astronomers were aware that meteorites burned up when they fell into our atmosphere. The reason, notes Allie Anderson, a graduate student in Aeronautics and Astronautics, is friction with air molecules (remember, thereâs no air in outer space).
Earth's Atmosphere. The atmosphere is a mixture of nitrogen (78%), oxygen (21%), and other gases (1%) that surrounds Earth. High above the planet, the atmosphere becomes thinner until it gradually reaches space.It is divided into five layers. Most of the weather and clouds are found in the first layer.The atmosphere is an important part of what makes Earth livable. It blocks some of the Sun's dangerous rays from reaching Earth.t is divided into five layers. Most of the weather and clouds are found in the first layer. The atmosphere is an important part of what makes Earth livable. It blocks some of the Sun's dangerous rays from reaching Earth.