4/10/2023 0 Comments Meteor meteorite or meteoroidThe Chelyabinsk meteor (2013) was a superbolide, caused by a 20 metre undiscovered asteroid. L (bottom): Botswana bolide 2018 ( B Swanepoel/V van Zyl) L (top): Chelyabinsk superbolide 2013 ( YouTube) The following images show meteors of different sizes: On a planetary body with no atmosphere, there is no meteor, and in that case there may be an impact flash as the object hits the ground (like the one seen during a 2019 lunar eclipse). A fire in the skyĭepending on the brightness of a meteor, it may be called a fireball, bolide or superbolide and be accompanied by an airburst. But this tale might just as well be called Schrödinger’s Dog, seeing as no-one really seems to know the outcome of that particular meteoritic event, or will ever know without having seen it, because the story differs depending on who first told it, who can remember it and who now translates it. There is, after all, is the apocryphal Legend of The Nakhla Dog that was (as is often told) struck and killed by a meteorite from Mars in 1911. There are some wonderful wistful moments where the astronauts ponder the asteroid strike on the spacecraft, with quotes like: “ There is no fair or unfair – to a meteorite, you get hit, you die.” In the 1965 movie, Voyage To The Prehistoric Planet (which interestingly is set in 2020 so worth a watch just to see what filmmakers in 1965 thought we would be up to now) one of a trio of spaceships en route to colonise Venus is struck and destroyed by an asteroid – and provides a classic case of confusing the terms “asteroid” and “meteorite”. People also want things to look the way they expect, which translates to what they see on Earth, even if the physics is wrong. Wthout the excitement of a huge asteroid ablaze in space, people might either be bored or presume that the budget didn’t stretch enough for special effects. Similarly in the movies, we hear fragments or debris of a comet or asteroid referred to as a “meteor cloud” (or swarm or storm) even though there can be no meteors at that stage.īut it’s not always the moviemakers’ fault. A space rock isn’t a meteor in space because there is no atmosphere in which it can burn up. But it’s only a meteor when it’s in the meteor phase, not before and not after. In the movies, an asteroid or comet is commonly referred to as “the meteor” from the first moment it is observed. There is a full glossary of terms at the end of this post. There is also a distinction based on location and sequence: meteoroids travel into the atmosphere from interplanetary space meteors occur in the atmosphere and meteorites reach the ground as the spent end product. Meteoroids and meteorites refer to natural objects, whereas meteors can result from the passage of any object, natural or artificial, travelling through the atmosphere – whether asteroid, comet, satellite, space capsule, alien space probe, and so on. The part of the meteoroid that survives the meteor stage and falls to Earth. In meteor astronomy, a meteor is caused by a meteoroid irrespective of the size of the incoming object causing it (whether an asteroid or any other natural body). There is still a meteoroid (or something) ‘inside’ the meteor, burning up. Meteor. The bright phenomenon (heat, light, ionization) that we see in the sky due to a meteoroid (or any other object) burning up in the atmosphere. Meteoroid. The solid part of a natural body passing through the atmosphere and the physical source that feeds a meteor. (There is more on meteoroids below, in particular the size debate.) The three terms are, on the face of it, easy enough to understand: The IAU also acknowledges the persisting confusion not only by the general public but also in the scientific literature. This includes clarifying the difference between meteoroids, meteors and meteorites, as well as other related terms. The International Astronomical Union (IAU) sets out certain definitions relating to meteor astronomy. The official definition of meteoroid, meteor and meteorite So what is the difference between meteoroids, meteors and meteorites?īut before that, if you want to know the difference between asteroids and comets, read this, or to read about impacts and the simulated impact scenarios being run by NASA, read this. The term meteor, in particular, is most often misleadingly used in the movies and as a result its misuse begets misuse – in real life too, including in the news media. And so asteroids and comets are called meteors, meteoroids and meteors are called meteorites, and meteorites are called…well, meteorites, actually. It’s a dilemma universally acknowledged in Hollywood that the makers of asteroid and comet disaster movies must ignore the laws of physical science and make events look the way moviegoers expect from their own experience on Earth, otherwise they won’t believe it.
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