Credit & Copyright: Enrique Luque Cervigón
Explanation: This year Aphelion, the point in Earth's elliptical orbit when it is farthest from the Sun, occurs tomorrow, July 4th. Of course, that doesn't affect the seasons on our fair planet. Those are determined by the tilt of Earth's axis of rotation and not Earth's distance from the Sun, so July is still winter in the south and summer in northern hemisphere. But it does mean that on July 4th the Sun will be at its smallest apparent size. This composite neatly compares two pictures of the Sun taken with the same telescope and camera on the dates of Perihelion (closest approach) and Aphelion in 2008. The image labels include Earth's distance in kilometers from the Sun on the two dates. Otherwise difficult to notice, the change in the Sun's apparent diameter between Perihelion and Aphelion is clear. The difference amounts to a little over 3 percent.
Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)
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9 comments:
As a kid, I have always loved dreaming about the aphelion, perhilion and the way the earth's very rotational velocity changes as does its speed in racing around the sun as it arcs through these twin apexes on the ellipse. Well, that was part of the depraved childhood thing.
More cataclysmic effect has smitten earth into swinging changes in her climate by her own belches. Remember the 2004 Boxing Day tsunami, where there were theories that the earth's axis had precessed so rapidly that its tilt was closer to the ecliptic, altering the incidence of all major earth circles, ie the Arctic and Antarctic, as well as the Capricornian and Cancerian Tropics.
You can well imagine the kind of effect that would have on the weather and the tides. The only constant then, is the Equator, Middle Earth herself!!
Precession of the earth's rotational axis with respect to the celestial sphere is a constant,which was why once upon a time, the North Star was Thuban in the constellation Draco, Vega in the constellation Lyra and one book by Iain Nicolson listed Algol in Perseus, (or rather in Medusa's head) if I am not mistaken (sorry, I left this hobby in 1979). With the naturally slow precession of the earth, it tracked to stay over Polaris, the tail of Ursa Minor, for the current day.
Yes, I have doubts about Algol. A little too far from the precession circle, don't you think? But if Vega was once the North Star, then it lies in Perseus' neigbourhood. It must be remembered that the solar system itself is riding on the periphery of the Milky Way, so maybe this isn't far-fetched.
Care to Pursue this any further?
my guess, the world like a cracked egg will be affected, earh's moves within itself plus gravity changes might cause some tsunami n the likes,,,just wait abit, you will see what happens!!,,,bet you!!
,,,the sea is huge today at kapas, never seen it such!! we were surfing the waves infront of the longhouse beach front,,,geee just great yaaaa!!
Capt.
Jeffrey,
The pilot, physicist, astronomer and heir to Shakespeare.
I cannot pursue the matter because I only know that the stars, and all other heavenly occurrences simply look heavenly. I took just one course in Introduction to Astronomy, but didn't get to do much viewing, only theory and I didn't pursue it as a hobby either, which I regret because I cannot point out the beauty and secrets of the heavens to my kids now...but do carry on and tell me more!
PirateKing,
Glad you are having fun as usual, ...heheh
How's the bitch?
Starlight star bright
First star I see tonight
I wish I may, I wish I might
Have the wish I wish tonight
The distractor strikes again!
Zendy,
did you get your wish?
was it catalysmic as Jeffrey described?
;)
Well it was very, very windy during the night. The mission had to be aborted - impossible to lift off, the rotors were unco-operative lah.
Morning - all systems go! Yay :D
hahaha - here we go again.....
Zendra,
And we have lift-off!
Ladies ,,,,ladies behave behave,,,,pls yaa!!hehehe
Uban
Capten!
She started it!!!!
hahaha...
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