Search results
Results from the WOW.Com Content Network
An aeroshell is a rigid heat-shielded shell that helps decelerate and protects a spacecraft vehicle from pressure, heat, and possible debris created by drag during atmospheric entry. Its main components consist of a heat shield (the forebody) and a back shell.
The superbubble Henize 70, also known as N70 or DEM301, in the Large Magellanic Cloud [1]. In astronomy a superbubble or supershell is a cavity which is hundreds of light years across and is populated with hot (10 6 K) gas atoms, less dense than the surrounding interstellar medium, blown against that medium and carved out by multiple supernovae and stellar winds.
Inspired by the 1937 science fiction novel Star Maker by Olaf Stapledon, [5] the physicist and mathematician Freeman Dyson was the first to formalize the concept of what became known as the "Dyson sphere" in his 1960 Science paper "Search for Artificial Stellar Sources of Infra-Red Radiation". Dyson theorized that as the energy requirements of ...
The shell bound by two concentric, similar, and aligned ellipsoids (a homoeoid) exters no gravitational force on a point inside of it. [7] Meanwhile, the shell bound by two concentric, confocal ellipsoids (a focaloid) has the property that the gravitational force outside of two concentric, confocal focaloids is the same. [8]
Surrounding it is a thin shell of perfect fluid where p = ρ. On the exterior is true vacuum, where p = ρ = 0. The dark-energy-like behavior of the inner region prevents collapse to a singularity, and the presence of the thin shell prevents the formation of an event horizon, avoiding the infinite blue shift [jargon].
An example comes from considering a scalar field in D-dimensional Minkowski space.Consider a Lagrangian density given by (,).The action is = (,). The Euler–Lagrange equation for this action can be found by varying the field and its derivative and setting the variation to zero, and is:
In chemistry and atomic physics, an electron shell may be thought of as an orbit that electrons follow around an atom's nucleus. The closest shell to the nucleus is called the "1 shell" (also called the "K shell"), followed by the "2 shell" (or "L shell"), then the "3 shell" (or "M shell"), and so on further and further from the nucleus.
An inflated canopy holding high pressure air around an otherwise airless world to create a breathable atmosphere. The pressure of the contained air supports the weight of the shell. This type of structure could also be built on top of an existing smaller planet or asteroid, enabling it to support human-friendly atmosphere. [3] [4] [5]