Sentences with phrase «by radiation pressure»

Ehrenreich and his team think that such a huge cloud of gas can exist around this planet because the cloud is not rapidly heated and swept away by the radiation pressure from the relatively cool red dwarf star.

Atoms are slowed and cooled by radiation pressure from laser light and then trapped in a bottle whose walls are magnetic fields.

Vinković's model «shows how dust grains propelled by radiation pressure can travel from the disk's hottest regions to its icy outer edges,» says astronomer Dániel Apai of the Space Telescope Science Institute in Baltimore, Maryland.

Not exact matches

«The bottom line is that we're paying a lot more attention to modeling very small accelerations, such as those exerted by solar radiation pressure, than previous missions have had to do,» said Michael Moreau, OSIRIS - REx flight dynamics system manager at Goddard.

Manufactured in bulk, low - cost Sprites could be deployed and networked by the hundreds or thousands to create space - based sensor arrays of unprecedented breadth, with each craft so lightweight that it could operate without propellant, shifting or maintaining its orbit solely through the radiation pressure of starlight or the forces imparted by a planet's magnetic field.

The X-ray data also indicates that radiation from material surrounding this black hole has consistently surpassed the so - called Eddington limit, defined by a balance between the outward pressure of radiation from the hot gas and the inward pull of the gravity of the black hole.

Having a mass of only less than seven per cent of the mass of the Sun, they are unable to create sufficient pressure and heat in their interiors to ignite hydrogen - to - helium fusion, a fundamental physical mechanism by which stars generate radiation.

By coupling a nanostring to an optical waveguide, Kippenberg's lab recently demonstrated the ability to «hear» the gentle sound of photons flowing in a laser beam (each imparting a tiny radiation pressure force to the string).

The birds are a textbook example of adaptive radiation, in which a single ancestor responds to a selective pressure — in this case, food availability — by diversifying into several species.

The smaller debris / meteoroids produced get spread around the orbit quite quickly (read: centuries or millennia) by various physical effects (ejection speeds from the comet; radiation pressure; Poynting - Robertson effect; Yarkovsky effect).

But the radiation fron the air above the surface is fixed by the pressure of the air which remains fairly constant at around one atmosphere.

Good arguments exist that the central regions should collapse first, producing a condensed protostar whose contraction is halted by the large buildup of thermal pressure when radiation can no longer escape from the interior to keep the (now opaque) body relatively cool.

«Any noise in the system — pressure created by solar radiation, thermal, magnetic and gravitational effects — could perturb the gravitational wave,» ESA project scientist Paul McNamara explained via a Skype call last week.

«The hypothesis to be tested experimentally in ADAPT was whether longer - lasting selective pressure by UV radiation results in a higher UV resistance, as well as in a higher resistance against further «extreme» environmental factors that exist in space,» Wassmann said.

«Once a protostar reaches a threshold of about 20 solar masses, the pressure exerted by its radiation should overpower gravity and prevent it from growing any bigger.

There could be three evolutionary processes could explain this adaptive radiation of hominins: 1) the occupation of novel niches for species living in a highly productive but spatially constrained region when there are deep fresh water lakes in the EARS [46] and 2) the lakes themselves creating spatial structure producing population isolation and vicariance and 3) repeated periods of increased resource availability stimulated adaptation and radiation followed by periods of environmental stress when the lakes rapidly dried up imposing strong selection pressures [28].

Is star formation triggered mainly by shockwaves from exploding stars, or the pressure created by radiation and stellar winds from massive stars — or can those processes get in the way of the collapse?

«Optomechanics is an area of research in which extremely minute forces exerted by light (for example: radiation pressure, gradient force, electrostriction) are used to generate and control high - frequency mechanical vibrations of microscale and nanoscale devices,» explained Gaurav Bahl, an assistant professor of mechanical science and engineering at Illinois.

But convection is less and less efficient when pressure decreases, while cooling by radiation is more and more efficient.

By Amber Bentley (Aged 11) In just 16 pages, this wonderful book covers the structure of the atmosphere, solar radiation, the water cycle, clouds, fronts, convection, air pressure, air masses, the global atmospheric circulation, making weather observations, forecasting, synoptic charts, hurricanes, regional climate, palaeoclimates and anthropogenic climate change.

For the adiabatic process the formula considers the partial pressures and specific heats of the gases forming the atmosphere, an adiabatic constant and corrective coefficients for the heating caused by water condensation in the wet atmosphere and for the absorption of infrared radiation by the atmosphere.

The advantages are said to be: 1) the pressure drop caused by the mesh spreads the airflow evenly over the full surface of the absorber, and 2) the first layer of mesh acts as a radiation shield to reduce the radiation from the hotter inner layers toward the glazing.

Now the radiation pressure in the cavity between surface and absorber has increased by a factor of 2.7, due to the higher temperature, but the additional expansion and cooling this causes is still utterly negligible (a further 1.7 parts in 1E11).

According to the second law of thermodynamics, the surface can not affect to the solar photon stream and the radiation pressure exerted by the atmosphere can not affect to the surface.

I will keep bring this up every month or two until 1) someone says they clearly see what I am talking about or 2) someone clearly explains how this radiation pressure created by these LW radiations, up from the ground, 1/2 down from GHGs does not cause a pressure which will expand the atmosphere and by thermodynamics fundamental equations will cool the atmosphere in exactly an equal amount.

The compression WORK gets converted to heat; BUT, once the collapse stops when teh pressure builds up enough to stop the fall, then the gas starts to lose energy and cool, by radiation, and eventually the whole thing would settle at a fixed Temperature.

CO2 molecules outnumber water molecules in the upper atmosphere, where water vapor is limited by the low saturation vapor pressure, and this is where radiation to space matters, so CO2 plays a big role in how much energy is radiated to space.

There is a temperature gradient caused by atmospheric radiations — warm air rises, expands and cools in lower pressure at height — but this is just the lapse rate and doesn't create cooler temps at height.

The altitude where the radiation to the cosmos takes place with the associated cooling of the top of the air is near t = 1 from the top of the air, that is at a pressure (1 / tmax H2O)(1/4.5) or (1 / tmax CO2)(1/1.45); the line by line computation of figure 6 - C is a morphing from figure 6 - A.

Temperature is proportional to pressure, therefor Earth atmospheric temperature is formed by background radiation pressure, and distance from the shielding effect of the Sun

Since the water vapor pressure equals the saturation vapor pressure, there is no net evaporation or condensation so there is no flow of energy from the top wall to the water and water vapor or vice versa by radiation or conduction nor to or from the water vapor to the water and the temperature of all components will not change with time.

For current CO2 partial pressure or concentration I calculate a distance of 3600 m of traverse through the earth's atmosphere by «IR radiation» before the absorbable IR is «filtered out» and reduced to zero.

The simpler approach to calculating the downward radiation from a given gas by the total concentration across say 10 km of atmosphere is going to give a very approximate answer — this is because the absorption lines change their width with pressure and temperature.

We use the 9 climate variables of surface air temperature (SAT), sea level pressure (SLP), precipitation (rain), the top of atmosphere (TOA) shortwave (SW) and longwave (LW) full - sky radiation, clear - sky radiation (CLR, radiative flux where clouds do not exists), and cloud radiative forcing (CRF, radiative effect by clouds diagnosed from the difference between full - sky and clear - sky radiation, Cess et al. 1990).