More than 50 years after the last Apollo mission, the United States will try once again to land a craft on the moon on January 25, said the head of what could be the first private company to successfully touch down on the ...
Space Exploration
Nov 30, 2023
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1688
A study led by Western astrobiologist Catherine Neish shows the subsurface ocean of Titan—the largest moon of Saturn—is most likely a non-habitable environment, meaning any hope of finding life in the icy world is dead ...
Astrobiology
Feb 14, 2024
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6024
A large swath of Earth's oceans changed color over the past 20 years—and human activity is suspected to have caused it, a new study reports.
Environment
Sep 2, 2023
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1021
Scientists revealed Tuesday that they had discovered a vast, hidden landscape of hills and valleys carved by ancient rivers that has been "frozen in time" under the Antarctic ice for millions of years.
Earth Sciences
Oct 24, 2023
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1366
Japan's space agency said Thursday that its first lunar mission hit the tiny patch of the moon's surface it was aiming for, in a successful demonstration of its pinpoint landing system—although the probe appears to be lying ...
Space Exploration
Jan 25, 2024
24
408
A strong El Niño event is going to wreak havoc on global surface temperature and trigger several climate crises in 2023–2024, according to researchers from the Institute of Atmospheric Physics (IAP) of the Chinese Academy ...
Earth Sciences
Sep 28, 2023
2
489
What are "fairy circles"? They are polka dots of bare earth, regularly scattered across arid grasslands. Scientists first described fairy circles in Namibia in the 1970s and sparked a global debate in the scientific community ...
Ecology
Apr 8, 2023
1
509
In 2022, a third La Niña year brought much rain to Australia and Southeast Asia and dry conditions to the other side of the Pacific. These patterns were expected, but behind these variations there are troubling signs the ...
Environment
Jan 15, 2023
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916
A large part of the world's liquid freshwater supply comes from groundwater. These underground reservoirs of water—which are stored in soil and aquifers—feed streams, sustain agricultural lands, and provide drinking water ...
Earth Sciences
Dec 21, 2022
2
503
A collaborative research team lead by the University of Massachusetts Amherst has recently revealed that rotifers, a kind of microscopic zooplankton common in both fresh and ocean water around the world, are able to chew ...
Environment
Nov 9, 2023
2
325
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
