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Hour Circle
Related Category: Astronomy: General
in astronomy, a secondary axis in the equatorial coordinate system.
hour circle
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Hour Circle
A passing through the . The position of the hour circle and the azimuthal coordinate of a celestial body lying on it is specified by its .
, , , ...
Crop Circles:
Excerpt from the Encyclopedia Britannica without permission.
A transit circle is used to make two measurements - the time at which a star crosses the meridian, as it travels from East to West across the sky, and the angle of the star above the horizon.
Antarctic Circle
The globe of the Earth showing the Antarctic Circle at 66.5 degrees south of the equator.
Kepler planet circles
two suns
DR EMILY BALDWIN
ASTRONOMY NOW
Posted: 15 September 2011 ...
The acceleration a = v2/R towards the center, needed to keep an object moving in a circle, is called its centripetal acceleration, from Latin petere, to move towards. By Newton's laws, any acceleration requires a force.
Definition: greatcircle: The line of intersection of the surface of a sphere and any plane which passes through the center of the sphere.
Space Tragedies9 Planets in Nine DaysAstronomy 101
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Circle - A curve on which all points are equidistant from the center
Circular Speed - The speed that causes an orbiting body to have a circular orbit rather than an elliptic one ...
The Circle is the sixth studio album by the Portland, Oregon punk rock band The Wipers, released in 1988. This was intended by the band to be the last Wipers album....
album to be the last The Wipers album.
hour circle: a great circle on the celestial sphere that passes through the celestial poles. It is orthogonal to the celestial equator.
Hour Circle (i) A great circle passing through an object and the celestial poles. (ii) The setting circle on the polar axis of an equatorial mount.
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Hour Circle
A great circle passing through the celestial poles - i.e., perpendicular to the celestial equator.
Hourglass Nebula ...
Great circle -- An imaginary circle on the surface of a sphere whose center is at the center of the sphere.
Great circle. A circle on the surface of a sphere whose plane passes through the centre of that sphere.
H
Halo, galactic. A roughly spherical shaped region around the main part of the Galaxy.
GREAT CIRCLE
A great circle is an imaginary circle on the surface of a sphere whose plane passes through the center of the sphere.
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setting circles
circular scales on the two axes of an equatorial mount that help an observer point a telescope to a specific right ascension and declination
shock wave ...
Circle illustration
In classical geometry, a radius () of a circle or sphere its any line segment from its center to its perimeter. By extension, the radius of a circle or sphere is the length of any such segment, which is half the diameter.
circles of latitude
prime meridian
hour circle through 1,
Greenwich celestial meridian,
local celestial meridian ...
Circled by distinctive rings and attended by a coterie of a dozen and a half moons, Saturn has been called one of the most intriguing planetary realms in the solar system.
Circle of perpetual occultation. See under Circle.
Báb
Constitution of Iran : Part One ...
Circles have e=0 because their diameters are all the same. If an ellipse has one very short diameter, and one very long one, then it is a very stretched-out ellipse, and has an eccentricity nearly equal to 1.
Circlet
the western fish; the circlet is formed by gamma Psc, b Psc, theta Psc, iota Psc, 19 Psc, lambda Psc and kappa Psc.
circle 1252 684 86 Charon circle 1038 632 188 (134340) Pluto
Sedna
circle 342 1305 137 (90377) Sedna ...
A circle has an eccentricity of 0.0, a parabola 1.0.
3
The inclination of a planetary orbit is measured with respect to the plane of the earth's orbit.
We circle around a star that was born approximately 5 billion years ago, in a universe that is estimated at 13.7 billion years old. Past philosophers have thought of the universe as a static thing - no beginning, no end, and especially unchanging.
: (circled) in the globular cluster M4.
The star is now a , a stable star with no nuclear fuel. It radiates its left-over heat for billions of years.
The circle shows the location of the class G subdwarf-dwarf Mu Arae (in the constellation Ara). Like 55 Cancri, it has four planets, described below.
The Circle with a point at its centre (⊙) is an ancient solar symbol featuring a circle with its center marked with a dot.
Symbolism
It can symbolise: ...
The circle shows a field with a five degree diameter. Stars to magnitude 6.5 are shown. The path of Jupiter during 2010 is also shown.
Draw circles representing primary mirrors. Start with a radius of 1cm and draw several up to 15cm radius. Cut them out then paste them on thick card or plywood.
Cut 3 circles out of the tagboard. Two of them should be about 4 cm in diameter. The third should be about 3 cm in diameter.
great circle - (n.)
The intersection of a plane that passes through the center of a sphere with the surface of that sphere; the largest possible circle that can be drawn on the surface of a sphere.
greenhouse effect - (n.) ...
A semi-circle of stars between Boötes and Hercules marks the golden crown worn by Princess Ariadne of Crete when she married the god Dionysus. The crown is said to have been made by Hephaestus, the god of fire, and was studded with jewels from India.
A full circle has 360 degrees (°). One degree equals 60 arc minutes (') and one arc minute equals 60 arc seconds (''). The angular size of the Moon viewed from the Earth is about 0.5°.
1°= 60', 1'= 60'' ...
THEMIS circles Mars every two hours, taking visible and infrared images of the planet and sending them back to Earth. Christensen and his colleagues decipher the images to understand the makeup of Martian rocks.
A great circle passing through the Earth's rotational poles and through the zenith (the point directly overhead) of a location on the Earth.
Reference: ...
Rings encircle Jupiter, although they are far darker and skimpier than those of the flashier planet Saturn. The rings may consist of material that was "sandblasted" off the surfaces of Jupiter's moons by collisions with meteorites.
A great circle passing through the celestial poles - i.e., perpendicular to the celestial equator. [H76]
Hourglass Nebula
A compact H II region in the center of M8. [H76]
Hoyle-Narlikar Theory ...
8. A circle has an eccentricity of zero. HINT
9. The astronomical unit is a distance equal to the semi-major axis of Earth's orbit around the Sun. HINT ...
The inner circle will represent Mercury's orbit and should only be about 3 feet in diameter. Mercury completes one orbit around the Sun in just 88 days.
VERTICAL CIRCLE - Arc of a great circle drawn from the zenith through a star and perpendicular to the horizon.
The larger circle of which an epicycle revolves (the earth in this case).
Degenerate Matter
Extremely high density matter in which pressure no longer depends on temperature due to the quantum mechanical effects.
Make sure to circle May 15 on your calendar, the night that stages a total eclipse of the Moon. The show begins a hair's-breadth after 10 p.m.
an imaginary circle on the celestial sphere that connects the zenith to the north (or south) celestial
Messier objects
the 107 bright deep-sky objects that belong to a catalog compiled by French astronomer Charles Messier in the 1700s ...
In scientific circles, the leading explanation for the explosion is the airburst of a meteoroid 6 to 10 kilometers (4-6 mi) above the Earth's surface.
Asteroids that circle the Sun following Jupiter orbit.
Troposphere
The lowest part of the Earth's atmosphere.
Digital Setting Circles (DSCs) are a small special purpose computer, mounted on or near a telescope.
An object which circles another object.
Shepherd Moon
Name given to tiny moons which orbit outside and inside a planet's ring system ...
[20.3] APOLLO 8 CIRCLES THE MOON
[21.0] The Eagle Has Landed
[21.1] PREPARING FOR THE MOON LANDING / APOLLO 9 & 10 ...
Digital setting circles (DSC) allow a computer to help you manually aim your scope. They appeal to the observer who likes to understand the concepts of astronomical coordinate systems, but have the computer do the actual math.
As the spacecraft circled the comet's nucleus, it would have dropped a lander for a soft touchdown on Wirtanen's surface. The lander would have provided a close-up look at the comet's physical condition and chemical composition.
Scientific Balloon Circles South Pole on Search for Antimatter
A group of Japanese and American scientists bundled in thick orange jackets, hats, boots and gloves have ventured down to Antarctica on a search for antimatter.
zodiac: Greek for "circle of animals." The set of constellations situated along the ecliptic in the sky, through which the Sun, Moon, and planets move.
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The horizon, celestial equator, ecliptic, and galactic systems of celestial coordinates are based on the celestial horizon, celestial equator, ecliptic, and galactic equator, respectively, as the primary great circle.
Arc Degree A unit of angular measure in which there are 360 arc degrees in a full circle.
Arc Second Abbreviated arcsec.
That the orbits of the planets are ellipses, not circles, was first discovered by Johannes Kepler based on the careful observations by Tycho Brahe. erg/sec = 1e-10 kilowatts.
celestial equator great circle that is a projection of the Earth's equator onto the sky. Always intercepts horizon at exact East and exact West point. Its meridian altitude = (90 degrees - observer's latitude).
 See also: Earth, Time, Sun, Light, Planet
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