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Meteoroid. A meteoroid shown entering the atmosphere, causing a visible meteor and hitting the Earth's surface, becoming a meteorite. A meteoroid ( / ˈmiːtiərɔɪd / MEE-tee-ə-royd) [1] is a small rocky or metallic body in outer space . Meteoroids are distinguished as objects significantly smaller than asteroids, ranging in size from grains ...
Astronomical transit. Phobos transits the Sun, as viewed by the Perseverance rover on 2 April 2022. In astronomy, a transit (or astronomical transit) is the passage of a celestial body directly between a larger body and the observer. As viewed from a particular vantage point, the transiting body appears to move across the face of the larger ...
The celestial equator is defined to be infinitely distant (since it is on the celestial sphere); thus, the ends of the semicircle always intersect the horizon due east and due west, regardless of the observer's position on Earth. At the poles, the celestial equator coincides with the astronomical horizon. At all latitudes, the celestial equator ...
28.2 (in 2003) [14] Halley's Comet, Comet Halley, or sometimes simply Halley, officially designated 1P/Halley, is the only known short-period comet that is consistently visible to the naked eye from Earth, [15] appearing every 75–79 years. [1] It last appeared in the inner parts of the Solar System in 1986 and will next appear in mid-2061.
An atmospheric window is a region of the electromagnetic spectrum that can pass through the atmosphere of Earth. The optical, infrared and radio windows comprise the three main atmospheric windows. [2] The windows provide direct channels for Earth's surface to receive electromagnetic energy from the Sun, and for thermal radiation from the ...
Visible pass of the International Space Station and Space Shuttle Atlantis over Tampa, Florida, on mission STS-132, May 18, 2010 (five-minute exposure). An orbital pass (or simply pass) is the period in which a spacecraft is above the local horizon, and thus available for line-of-sight communication with a given ground station, receiver, or relay satellite, or for visual sighting.
Apparent retrograde motion is the apparent motion of a planet in a direction opposite to that of other bodies within its system, as observed from a particular vantage point. Direct motion or prograde motion is motion in the same direction as other bodies. While the terms direct and prograde are equivalent in this context, the former is the ...
In this general sense, occultation applies to the visual scene observed from low-flying aircraft (or computer-generated imagery) when foreground objects obscure distant objects dynamically, as the scene changes over time. If the closer body does not entirely conceal the farther one, the event is called a transit.