The meteorite has gained its fame from one of the world’s best-loved superheroes, Superman. The Man of Steel’s Achilles’ heel is the mineral kryptonite – and the villains in his life have probably thanked all the meteorites that encapsulated the small substance.

But what is a meteorite? And where does it come from?

The universe consists of heavenly bodies – mainly planets, galaxies, stars, and asteroids (rocky, metallic objects that look like rocks; also known as minor planets). Some of these asteroids take a one-way trip to Earth – should they decide to continue their suicidal collision course, they become meteoroids. When a meteoroid touches our atmosphere, the friction causes it to ignite, and like a match, and burns it.

Now by theory, the meteoroid is supposed to burn up completely. However, in most cases, it doesn’t. The leftover meteoroid has no other choice but to land on the Earth’s surface. It manifests itself as a falling or shooting star (at this point, it is now called a meteor), touches ground and voila! A freshly-landed meteorite is born.

Some of the meteorites have been analyzed. It has been confirmed that their points of origin are mostly lunar (from the moon) and/or Martian (from Mars). They may look like regular rocks, but it is living proof that the existence of other life forms may not be so impossible after all.

The post Meteorite appeared first on Planet Facts.

A jet stream is a band of fast-flowing air at very high altitudes flowing generally from west to east. It can either be a polar jet or a subtropical jet, depending on how close to the polar caps or equator it is. Pilots during World War II first discovered its existence in the atmosphere when they were slowed down very severely while flying. Now, pilots know enough to go with and not against a jet stream so they can travel faster through the air. They may start, stop, split into multiple paths, rejoin, or go in a totally different or even opposite direction, but as long as they follow the path of the jet stream, they should not have any trouble at all with flying.

Why is it called a Jet Stream?

The post Jet Stream appeared first on Planet Facts.

A Meteor that has not entered Earth's atmosphere is called a meteoroid. Earth's atmosphere usually burns up most of these meteoroids (now called a meteor once it enters the Earth's atmosphere). It is the burning up of meteors which cause the bright flare seen in the sky; hence the term: fireballs.

The earth's atmosphere usually burns up most fireballs, but there are a rare few that survive both the atmosphere burn and the ground impact; these are called meteorites, and are usually found in impact craters. Some impact are so strong, the entire meteor is vaporized, leaving no trace or meteorite in its crater.

There are a few percentages of meteoroids that do enter Earth's atmosphere yet are able to escape its gravity and pass out again. These meteoroids are sometimes called Earth-grazing fireballs.

The post Fireball appeared first on Planet Facts.

“Isotope” is Greek for “at the same place” and this term was suggested to Soddy by Scottish physician Margaret Todd the next year after he shared his ideas with her. The name defines itself'isotopes are atoms which have the same atomic number or the same number of protons but not neutrons. The mass number or the total number of nucleons in the nucleus is therefore different, because this is the sum of the number of protons and neutrons.

Carbon, for instance, has the atomic number of 6 because of its 6 protons, but not all carbon in and on the earth has the same number of electrons. There are carbon-12 and carbon-13, among others, and these two isotopes have the mass numbers 12 and 13 respectively. The next time you see the name of an element with a hyphen and a number following it immediately, that's an isotope, and the number means the number of neutrons it has.

The post Isotope appeared first on Planet Facts.

A jet usually is a westerly wind, flowing from the west to the east, its path typically meandering. It's very much like a river or an ocean current, often as fast as 230 miles (370 km) per hour, starting as one stream, stopping, splitting into two or more parts, combining into one stream, or flowing in various directions even including the reverse of the general direction of the main jet.

The main jets are located between the troposphere and the stratosphere, or what is called the tropopause. The strongest though lower jets, called polar jets, are those near the north and south poles. The somewhat weaker but higher jets, called subtropical jets, are those nearer the equator.

If you want to easily remember what a jet is, simply think of it as a pilot's aid: Jets were first discovered by World War II pilots who found struggled with flying because of these high winds. Now a jet pilot knows to go with instead of against a jet to travel faster and much more smoothly over the ground.

The post Jet appeared first on Planet Facts.

If you recall your science lessons from school, you know that the earth is surrounded by several layers of air called the atmosphere, as do the other planets in the solar system. It is what allows us to breathe; it lets breathable air circulate within the boundaries it creates and even protects us from objects which may fall from outer space.

The layers include: troposphere, stratosphere, mesosphere, thermosphere and exosphere. The ionosphere is comprised of the outer portion of the mesosphere, thermosphere and exosphere and it is so named because it is composed of plasma, meaning it is ionized by radiation from the sun.

Ionization is the process in which negative free electrons escape from the atoms or molecules originally containing them, and the opposite process, called recombination, is when photons are released from atoms or molecules because of captured free electrons.

The balance between ionization and recombination determines ionosphere ionization. What does this have to do with you? It plays a very important role in radio propagation: the ionosphere is the reason we can communicate with people from the other side of the globe through radio waves.

The post Ionosphere appeared first on Planet Facts.