Wiktionary
n. (context physics English) The pressure exerted by electromagnetic radiation on an object on which it impinges, as a consequence of its momentum.
WordNet
n. the minute pressure exerted on a surface normal to the direction of propagation of a wave [syn: corpuscular-radiation pressure]
Wikipedia
Radiation pressure is the pressure exerted upon any surface exposed to electromagnetic radiation. Radiation pressure implies an interaction between electromagnetic radiation and bodies of various types, including clouds of particles or gases. The interactions can be absorption, reflection, or some of both (the common case). Bodies also emit radiation and thereby experience a resulting pressure.
The forces generated by radiation pressure are generally too small to be detected under everyday circumstances; however, they do play a crucial role in some settings, such as astronomy and astrodynamics. For example, had the effects of the sun's radiation pressure on the spacecraft of the Viking program been ignored, the spacecraft would have missed Mars orbit by about 15,000 kilometers.
This article addresses the macroscopic aspects of radiation pressure. Detailed quantum mechanical aspects of interactions are addressed in specialized articles on the subject. The details of how photons of various wavelengths interact with atoms can be explored through links in the See also section.
Usage examples of "radiation pressure".
Their ships were met by such a blast of cosmic rays as they came toward Thett that the radiation pressure made it almost impossible to advance.
When the guts were scooped out of the star and replaced with a tiny cannonball of cold degenerate matter, the outer layers of the star, held away from the core by radiation pressure, began to collapse inward across a gap of roughly a quarter million kilometers of cold vacuum.
The Sun is a continuous source of a possible propulsive force, namely, solar radiation pressure.
The envelope will expand further, seeking a new balance between gravity and radiation pressure.
Despite the slow, continuing migration of the last photons outward from the stilled fusion processes, there was little radiation pressure, here at the heart of the Sun, to balance the core's tendency to collapse under gravity.
Gravitational forces and radiation pressure forces either are exactly compensated by some unknown mechanism in Sentinel, or do not act on the structure at all.
When a really massive star runs its course when the radiation pressure within is no longer strong enough to hold the outer layers against the star’.
When a really massive star runs its course when the radiation pressure within is no longer strong enough to hold the outer layers against the star's own ferocious gravity .
The radiation pressure from within would cause them to explode at once.
So the star reacts ter the squeeze by contracting a bit, then the radiation pressure takes hold and pushes it back out.
The energy density maintained within each PASER was enormous, and Blanca had seen a recording of an early test model bursting from radiation pressure.
The residual heat left in the cloud eventually balances the gravitational attraction, and equilibrium is found: a star has formed, a compact, stable body, with internal radiation pressure balancing out the tendency to collapse through gravitation.
The residual heat left in the cloud eventually balances the gravitational attraction, and equilibrium is found', a star has formed, a compact, stable body, with internal radiation pressure balancing out the tendency to collapse through gravitation.
They understood at once that this was an ultralight interstellar probe, a starwisp, drifting out to explore the Galaxy by radiation pressure, surveying other stars and reporting back by radio to its makers on their home planet.
Everything from worlds to sand grains moved in its own complicated orbit, defined by the gravitational forces of sun and planets, by solar wind and radiation pressure, and by asteroid interactions.