Sent: Monday, January 24, 2011 10:29 PM Subject: gravity
OK, this might sound dumb but,why do we have gravity here on earth? is it the mass of the earth holding us down or is it the rotation of the earth that’s holding us down? or both? Terry
The Earth’s mass creates the force we call gravity. It’s a force still not totally understood.
One fact: Mass alters time, our GPS system relies on time to calculate where you are on earth.
If the system didn’t make corrections for time differences between the GPS satellite ring and the earth’s surface, it wouldn’t have enough accuracy for most things..
If you had a twin brother who lived his live at 10,000 feet elevation, he’d become a different age than you living at sea level.
A mass will also bend light, we can see light from beyond our sun, and measure the bending effect of the Sun’s mass. keep this separate from a magnetic field, that’s another amazing thing, and I put a page up about this. There is so much misinformation about our magnetic field. Fact is…we’d have no atmosphere here on earth wihtout it….all would be blown into space by the solar winds (particles).
There are now some fairly good TV programs about our solar system that discuss some of these things. A great book to read is “A history of time” Stephen Hawkings, a permanent book for the shelf. Bottom line? Gravity is relative to mass, go to the moon, and you don’t weigh as much. If you take a 100 pound weight to the moon, and put it on an accurate scale, the number of pounds it weighed would reveal the weight of the moon relative to the mass of the earth as a percentage.
Got something to add or correct, please do!