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.
Fr.: matière intergalactique
Very low density material found indirectly in the space between galaxies. → intergalactic absorption.