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The dark area above the center of the solar disk is a sunspot. The antumbra (from the Latin ante "before" and umbra "shadow") is the region from which the occluding body appears entirely within the disc of the light source.
A point source of light casts only a simple shadow, called an "umbra". For a non-point or "extended" source of light, the shadow is divided into the umbra, penumbra, and antumbra. The wider the light source, the more blurred the shadow becomes. If two penumbras overlap, the shadows appear to attract and merge. This is known as the shadow ...
The expression "load cast", sometimes also called a load structure, refers to a load (the denser layer) sinking into its underlying (less dense) cast (mold). Related to load casts are flame structures, load waves, and anticrests. Extreme developments of load casts are pseudo-nodules and ball-and-pillow structures. In these extreme cases, the ...
The direction in space that is directly opposite the center of the Milky Way Galaxy, as viewed from Earth; considered as a point on the celestial sphere, the Milky Way's anticenter is in the constellation Auriga. Galactic Center The rotational center of the Milky Way galaxy, consisting of a supermassive black hole of 4.100 ± 0.034 million ...
Earth's shadow (or Earth shadow) is the shadow that Earth itself casts through its atmosphere and into outer space, toward the antisolar point. During the twilight period (both early dusk and late dawn ), the shadow's visible fringe – sometimes called the dark segment or twilight wedge [ 1 ] – appears as a dark and diffuse band just above ...
The differences between Earth's soil and lunar soil mean that plants struggle to grow in it. [ 32 ] [ 33 ] As a result long-term space missions could require complicated and expensive efforts to provide food, such as importing Earth soil , chemically treating lunar regolith to remove heavy metals and oxidize iron atoms, and selectively breeding ...
The Chang’e-6 probe withstood the high temperatures and collected the samples by drilling into the Moon's surface and scooping soil and rocks with a mechanical arm, according to a statement from the China National Space Administration (CNSA). The collected rock was crushed, melted and drawn into filaments about one third of the diameter of a ...
In geology and archaeology, dark earth is a substratum, up to 1 metre (3 ft 3 in) thick, that indicates settlement over long periods of time.The material is high in organic matter, including charcoal, which gives it its characteristic dark colour; it may also contain fragments of pottery, tile, animal bone and other artefacts.