> This orbital velocity at the surface of the earth is some 40,320 km/sec.
Huh? Is this right? That's really fast, like 24,800 miles per second, which is a significant fraction of c (the speed of light, 186,000 miles/sec). >10% of c, is this a typo?
Earth's orbit has a circumference of about 940 million km. Divide that by 365.25 days x 24 hrs/day x 3600 seconds/hr and I'm getting in the arena of 29.78 km/sec.
That’s the velocity of the earth around the sun. But “orbital velocity at the surface of the earth” is supposed to be the velocity a satellite in an orbit at ground level around the earth would have.
Huh? Is this right? That's really fast, like 24,800 miles per second, which is a significant fraction of c (the speed of light, 186,000 miles/sec). >10% of c, is this a typo?