A cloudy day can ruin a trip to the beach, a scenic picnic, and lots of other outdoor activities.
Earth Sciences
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7
A world-first study reverses the idea that the bulk of life in the ocean is fueled by photosynthesis via sunshine, revealing that many ocean microbes in fact get their energy from hydrogen and carbon monoxide.
Ecology
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War, budget cuts, a pandemic and a crash: For all its trials, Europe's ExoMars mission might be more deserving of the name Perseverance than NASA's Martian rover.
Space Exploration
Feb 3, 2023
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68
As plasma circulates in a fusion device, the surface of the device that faces the plasma erodes. This releases particles of surface material. Most erosion occurs through a process called sputtering, where a particle strikes ...
Plasma Physics
Feb 3, 2023
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3
Sometimes, the most complex problems can be solved with the simplest approaches. Such was the case for researchers at UC Santa Barbara as they tried to resolve a longstanding issue of fluid friction—the resistance between ...
General Physics
Feb 2, 2023
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140
ESA's geology training course PANGAEA has come of age with the publication of a paper in Acta Astronautica that describes the quest for designing the best possible geology training for the next astronauts to walk on the surface ...
Space Exploration
Feb 2, 2023
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17
Deep below the ocean surface, the light fades into a twilight zone where whales and fish migrate and dead algae and zooplankton rain down from above. This is the heart of the ocean's carbon pump, part of the natural ocean ...
Earth Sciences
Feb 2, 2023
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14
Pathogens are disease-causing organisms. By natural selection, they develop evasion mechanisms to outsmart the host's immune system and to get the upper hand. One way to support the immune system and fight back is medical ...
Evolution
Feb 2, 2023
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42
New research from William & Mary published in PeerJ reveals that decals intended to reduce incidents of bird window strikes—one of the largest human-made causes of bird mortality—are only effective if decals are placed ...
Plants & Animals
Feb 2, 2023
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6
Mineral oil lubricants protect engine parts from wear, and this effect is enhanced by adding polymer nanoparticles to the lubricating oil. A UK team has now discovered that epoxy functionalization of these nanoparticles further ...
Nanophysics
Feb 1, 2023
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19
In mathematics, specifically in topology, a surface is a two-dimensional topological manifold. The most familiar examples are those that arise as the boundaries of solid objects in ordinary three-dimensional Euclidean space R3 — for example, the surface of a ball or bagel. On the other hand, there are surfaces which cannot be embedded in three-dimensional Euclidean space without introducing singularities or intersecting itself — these are the unorientable surfaces.
To say that a surface is "two-dimensional" means that, about each point, there is a coordinate patch on which a two-dimensional coordinate system is defined. For example, the surface of the Earth is (ideally) a two-dimensional sphere, and latitude and longitude provide coordinates on it — except at the International Date Line and the poles, where longitude is undefined. This example illustrates that not all surfaces admits a single coordinate patch. In general, multiple coordinate patches are needed to cover a surface.
Surfaces find application in physics, engineering, computer graphics, and many other disciplines, primarily when they represent the surfaces of physical objects. For example, in analyzing the aerodynamic properties of an airplane, the central consideration is the flow of air along its surface.
This text uses material from Wikipedia, licensed under CC BY-SA
