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<<...Uranus
<<...Transit: 4:58 AM on 6/15/2001...>>
Transit means a celestial object lies due South in the sky, at its highest point in the sky, crossing the Meridian (the imaginary line connecting North and South cardinal points of the compass and the point at the very top of the sky, the Zenith.
<<...RA: 21h 49m 02.6s Dec: -13°58'39"...>>
R.A. means Right Ascension, the celestial counterpart of terrestrial Longitude. Dec. means Declination, the celestial counterpart of terrestrial Latitude. 1 hour of RA = 15 angular degrees (24 hours of RA = 360 angular degrees, the circumference of the sky).
<<...Azm: 48°53'11" Alt: -49°54'38"...>>
Azm means Azimuth, the angular distance in degrees from due North. East = 90 degrees Azimuth, South = 180 degrees, and West 270 degrees. North is bot 0 and 360. Alt means Altitude, the vertical (perpendicular) distance from the horizon to an object in the sky.
<<...Phase: 99.952%, Apparent magnitude: 5.76...>>
Phase means amount of visible surface illuminated by sunlight at time of observation. Apparent magnitude is the visual brightness of the object. This gets more complicated. Ages ago, our ancestors (some of them) decided that the brightest stars would be of 1st magnitude and the dimmest of 6th magnitude. The ability of telescopes to gather more light than our eyes means that early scale has been expanded in either
direction. The Sun is apparent magnitude -24, the moon -13 and the dimmest objects currently detectable less than 23rd magnitude. The visual intesity of one magnitude differs from the next by 2.53 times.
<<...Heliocentric ecliptical coordinates: l: 322°11'51.3" b: -00°43'02.1" r: 19.971892...>>
l = (for the coordinate system centered on the Sun, seen from above) angular distance eastward from the Vernal Equinox, the point of intersection on the terrestrial sky between Earth's orbit around the sun and the Earth's equator projected onto the sky, from which the angle between the two first increases northward.
b = the angular distance from the plane of Earth's solar orbit. " - " means southward.
<<...Geometric geocentric ecliptical coordinates: l: +324°43'11" b: -00°44'13" r: 19.440275...>>
l = (for the coordinate system centered on the Earth, seen from above) actual angular distance eastward from the Vernal Equinox, the point of intersection on the terrestrial sky between Earth's orbit around the sun and the Earth's equator projected onto the sky, from which the angle between the two first increases northward.
b = the angular distance from the plane of Earth's solar orbit. " - " means southward.
r = how much farther from the sun than is the Earth.
<<...Mean geometric ecliptical coordinates: l: +324°43'07" b: -00°44'13" r: 19.440247...>>
l = (for the coordinate system centered on the Earth, seen from above) the averaged angular distance eastward from the Vernal Equinox, the point of intersection on the terrestrial sky between Earth's orbit around the sun and the Earth's equator projected onto the sky, from which the angle between the two first increases northward as if Earth traveled around the sun at a constant speed.
b = the angular distance from the plane of Earth's solar orbit to the point of the object's averaged location. " - " means southward.
<<...True equatorial coordinates: RA: 21h 49m 03s Dec: -13°58'39"...>>
The actual celestial longitude and latitude of the object as seen from the center of the Earth.
<<...Apparent angular diameter: 3.60
The portion of the 360 degree circumference of the sky occupied by the visual disk of the object.
3.60 seconds of arc.
1 second of arc is 1/60th of a minute of arc, which is 1/60th of 1 degree of arc. 1 degree is 1/360th of a circle.
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