From the Album by VANGELIS entitled Albedo 0.39 – 4:20 in Length.
As I kid, I used to listen to this information. Interesting Earth Centered Facts done to music on the last cut also entitled Albedo.
The words from the Music Video are Denoted by •
• Maximum Distance from the Sun: 94,537,000
• Minimum Distance from the Sun: 91,377,000
• Mean (average) Distance from the Sun: 92,957,200
“Earth comes closest to the sun every year around January 3. It is farthest from the sun every year around July 4.”
See “The Reasons for the Seasons” below.
• Mean Orbital Velocity: 66,000 MPH.
• Orbital Eccentricity: 0.017
(How much Out-of-Round the orbit is). OK, they rounded, it’s actually 0.0167086. The Earth’s Orbit is nearly circular.
• Obliquity of the Ecliptic: 23° 27′ 8.26″
“The angle between the plane of the ecliptic (or the plane of the earth’s orbit) and the plane of the earth’s equator; the “tilt” of the earth.” It changes over time, the above figure is good for a century though. Our seasons are influenced by the tilt of the earth from the pathway the earth orbits around the sun. We’re 23° tilted to that orbit. This effects the angle sun light strikes the earth, and in most of the world, the more direct, or less angled, transfers more heat per square foot and effects the length of daylight vs darkness.
We are closer to the sun in the Northern Hemisphere’s Winter than in Summer.
“In the period of a year, the angle of incidence of incoming solar radiation varies by nearly 47° at any one place. Particularly at high latitudes, this results in a great seasonal temperature contrast.”
Equatorial areas experience seasons that are more consistent in temperature (than North and South areas) and daylight and darkness are around 12 hours each all year.
• Length of the Tropical Year, Equinox to Equinox: 365.24 Days.
“The length of a tropical year is the time it takes the Earth to complete a full orbit around the Sun, but it varies from year to year.”
When the sun returns it to a specific point as seen from earth.
“”An equinox is commonly regarded as the instant of time when the plane (extended indefinitely in all directions) of Earth’s equator passes through the center of the Sun.This occurs twice each year: around 20 March and 23 September.
In other words, it is the moment at which the center of the visible Sun is directly above the Equator (or, during the equinox, the sun will arc in such a way that, at noon, it will be below the vertical by the same number of degrees as your latitude).
In the northern hemisphere, the equinox in March is called the Vernal or Spring Equinox; the September equinox is called the Autumnal or Fall Equinox.””
• Length of the Siderial Year, Fixed Star to Fixed Star: 365.26 Days.
A sidereal year is the time taken by the Earth to orbit the Sun once with respect to the fixed stars. That extra .24 or .26 days, averaged is .25, there’s our need for leap years.
• Length of the Mean (average) Solar Day: 24 hours, 3 minutes, 56.555 seconds in Mean Solar Time.
See, there are more than 24 hours in a day, LOL.
• Length of the Mean (average) Sidereal Day: 23 hours, 56 minutes, 4.091 Seconds in Mean Solar Time.
“To end up facing the sun again, the Earth has to rotate for another four minutes. In other words, a solar day is how long it takes Earth to rotate once – and then some. A sidereal day is the amount of time needed to complete one rotation.”
Rats, we gained 4 minutes under the Solar Day but lost it under the Sidereal Day, those scientists ruin everything, LOL.
• Mass 6,600,000,000,000,000,000,000 Tons (Six Thousand Six Hundred Million Million Million Tons).
• Equatorial Diameter 7927 Miles.
• Polar Diameter 7900 Miles.
• Obliqueness 1/298
• Density 5.41 (The earth won’t float in water).
• Mean Surface Gravitational Acceleration of the Rotating Earth 32.174 Feet Per Second Per Second.
Not a misprint, 32 feet per second increasing by 32 feet per second until the terminal velocity is reached.
• Escape Velocity 7 Miles Per Second.
Mind you, this is for rockets to leave the influence of the Earth’s Gravity using current technology. UFOs, for example, if they employed some form of anti-gravity device or other forms of propulsion with unlimited fuel, could just fly away at any speed.
And finally, the name of the Album, used in its Scientific Sense:
• Albedo 0.39
The earth reflects 39% of the light that strikes it.