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Luna

Luna
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Armando Taborda
Armando Taborda
almost giving birth
2 years ago.
Demetrius Chryssikos has replied to Armando Taborda
;-))
2 years ago.
Demetrius Chryssikos
Demetrius Chryssikos
In Aristotle's (384–322 BC) description of the universe, the Moon marked the boundary between the spheres of the mutable elements (earth, water, air and fire), and the imperishable stars of aether, an influential philosophy that would dominate for centuries. However, in the 2nd century BC, Seleucus of Seleucia correctly theorized that tides were due to the attraction of the Moon, and that their height depends on the Moon's position relative to the Sun. In the same century, Aristarchus computed the size and distance of the Moon from Earth, obtaining a value of about twenty times the Earth radius for the distance. These figures were greatly improved by Ptolemy (90–168 AD): his values of a mean distance of 59 times the Earth's radius and a diameter of 0.292 Earth diameters were close to the correct values of about 60 and 0.273 respectively. Archimedes (287–212 BC) invented a planetarium calculating motions of the Moon and the known planets.
2 years ago.
Demetrius Chryssikos
Demetrius Chryssikos
In 1609, Galileo Galilei drew one of the first telescopic drawings of the Moon in his book Sidereus Nuncius and noted that it was not smooth but had mountains and craters. Telescopic mapping of the Moon followed: later in the 17th century, the efforts of Giovanni Battista Riccioli and Francesco Maria Grimaldi led to the system of naming of lunar features in use today.
The more exact 1834–36 Mappa Selenographica of Wilhelm Beer and Johann Heinrich Mädler, and their associated 1837 book Der Mond, the first trigonometrically accurate study of lunar features, included the heights of more than a thousand mountains, and introduced the study of the Moon at accuracies possible in earthly geography. Lunar craters, first noted by Galileo, were thought to be volcanic until the 1870s proposal of Richard Proctor that they were formed by collisions.
2 years ago.
Demetrius Chryssikos
Demetrius Chryssikos
Violent Volcanoes Knocked the Moon Off Its Axis Three Billion Years Ago.

A bunch of lunar volcanoes heated the Moon up so much, they changed its density, causing it to wander off its original axis aeons ago.
That’s according to a new study published today in the journal Nature. It all started when researchers from Southern Methodist University in Dallas noticed a lack of hydrogen deposits that are found in water-ice on the Moon’s poles—two regions that are permanently cloaked in shadow. So, since there’s no sunlight, shouldn’t there be hydrogen from ice there?
There should be, since the researchers used data from NASA’s Lunar Prospector mission in the late 1990s, which first pinpointed the hydrogen found near the Moon’s poles. That discovery was our first indication that ice exists on the surface in the first place. But what researchers found in this latest study was hydrogen from probable small trails of ice that branch out from each pole in opposite directions, each the same distance.
The team looked into it, and discovered that the cause was an extremely rare event called “total pole wander.” The team predicts that intense heating from lunar volcanoes heated the heavenly body up so much, they changed its density and its moments of inertia, causing it to tilt six degrees off its original axis, causing those hydrogen deposits to be knocked sideways from the Moon’s original poles.
“It’d be like the Earth’s North Pole going to Greenland,” study author Matt Siegler told The Verge.
At some point in the past, the craters at those poles were exposed to sunlight, deleting all ice found there forever. It was all thanks to the Moon wandering off its original axis. It’s still unclear why those trails of hydrogen exist, since any ice that’s there has clearly been exposed to sunlight. If it’s one thing we do know, however, it’s that there’s always more to learn about our planet’s Moon.
2 years ago. Edited 2 years ago.