◎◎◎ perigee ⪢⪢
Now about half a month later, the moon has orbited halfway around its path and it gets to its closest point to the
earth. We refer to this as perigee.
→ apogee, perihelion
http://qindex.info/i.php?x=9985
○○○ hang on ⪢⪢
Now, don't _____.
Nothing lasts forever but the
earth and sky.
It slips away and all your money won't another minute buy.
Dust in the wind.
All we are is dust in the wind.
Dust in the wind.
Everything is dust in the wind.
#song
http://qindex.info/i.php?x=6968
○○○ synchronous ⪢⪢
Because the moon's period of rotation is equal to its period of revolution, that is to say, because the moon takes the same amount of time to spin as it does to orbit the
earth, we from the
earth only ever see one face of the moon.
http://qindex.info/i.php?x=14015
○○○ erosion ⪢⪢
The reason we don't see the asteroid impacts on
earth the same way we see the craters on the moon is because on
earth those craters have been wiped away by the action of weather and erosion and weathering and the movement of tectonic plates.
http://qindex.info/i.php?x=10140
○○○ heliocentric ⪢⪢
In a heliocentric model the Sun, not the
Earth, is in the center and all other objects including the
Earth orbit the Sun. In this model the
Earth is moving in two ways. It revolves arround the Sun and it also rotates on an axis.
→ spin
http://qindex.info/i.php?x=14014
○○○ metabolism ⪢⪢
This male booted racket-tailed hummingbird lives on the brink of starvation. Just 2 hours without nectar and he could die. Humming birds have the fastest metabolisms on
Earth. Some need to visit 2 thousand flowers a day just to keep going.
http://qindex.info/i.php?x=15340
○○○ bedrock ⪢⪢
Finally and most importantly, mountains have deformed bedrock, meaning the layers of rock beneath the surface have been folded, faulted and tilted by the movement of
Earth's crust.
http://qindex.info/i.php?x=16113
○○○ drift ⪢⪢
More than that, the sun is what holds the solar system together. It's massive gravity is what keeps the
earth and all the other planets circling around it instead of drifting off into space.
http://qindex.info/i.php?x=19742
○○○ Hades ⪢⪢
So one day, when Persephone was picking flowers, the
earth opened beneath her feet and _____ came out of the
earth with his chariot and black horses. #Greece
http://qindex.info/i.php?x=24240