Fr.: cratère d'impact
A depression produced by the collision of a meteorite, asteroid, or comet with the surface of a planet or a satellite. Impact craters are the most characteristic surface features of solar system rigid bodies. They range in size up to hundreds or thousands of kilometers (where the impacts create giant basins as on the Moon, Mars, and Mercury).
Fr.: impact cosmique
A collision between two celestial objects, specially solar system bodies, with considerable consequences. Impact events involve release of large amounts of energy. Some examples are the 1908 Siberian → Tunguska event by a → comet, the → Barringer Crater, and the collision of an → asteroid with Earth 65 million years ago, which is thought to have led to the extinction of the dinosaurs and other species of the → Cretaceous-Paleogene period.
Fr.: risque d'impact
The danger of collision with Earth posed by solar system small bodies that pass near our planet. These objects include → near-Earth asteroids and nuclei of → comets. See also: → near-Earth object, → impact crater, → Torino scale, → Palermo scale, → Space Situational Awareness.
Fr.: ionisation par collision
The loss of orbital electrons by an atom of a crystal lattice which has undergone a high-energy collision.
Fr.: paramètre d'impact
1) A measure of the distance by which a collision fails being frontal.
Fr.: hiver par impact
The enormous drop in temperature and the related effects of the shrouding of Earth with soot and dust particles after the planet is struck by a sizable comet or asteroid. Such a phenomenon is believed to have killed off the dinosaurs 65 million years ago.
A general term used for all rocks affected by, or produced by, the → shock waves and other processes generated by hypervelocity → meteorite → impact events. Impactites occur in and around the → impact crater, typically as individual bodies composed of mixtures of melt and rock fragments, often with traces of meteoritic material.
A natural impacting body, such as a comet, asteroid, or planet. It can also be a space probe designed to collide with an astronomical body in the solar system.
Impactor, from → impact + -or a suffix forming agent nouns.
Barxordgar, from barxord, → impact, + -gar agent suffix, from kar-, kardan "to do, to make" (Mid.Pers. kardan, O.Pers./Av. kar- "to do, make, build," Av. kərənaoiti "makes," cf. Skt. kr- "to do, to make," krnoti "makes," karma "act, deed;" PIE base kwer- "to do, to make").
index of refraction
Fr.: indice de réfraction
Same as → refractive index.
Fr.: facteur intégrant
A function that converts a → differential equation, which is not exact, into an → exact differential equation. This is done by multiplying all terms of the original equation by the integrating factor.
To act upon one another; have a mutual or reciprocal action.
Fr.: binaire en interaction
Fr.: galaxies en interaction
Galaxies that are close enough for their mutual gravitational attraction to produce perturbed shapes or extruded filaments of stellar material, called → tidal tails. Most galaxies are in clusters, and gravitational interactions between them are common.
General: Mutual or reciprocal action or influence.
Capable of acting on or influencing each other
1) Acting one upon or with the other.
Fr.: absorption intergalactique
Fr.: nuage intergalactique
→ Intergalactic matter in the form of clouds.