Very good questions. I wish more folks would consider them.


Gravity is maximum at the earths surface. Surprise ?
All the earth's mass in one side of your body.

Pendulum clocks run slower at altitude or depth.
Vibrating mass clocks (accelerometer type ) run faster at altidude or
depth.
Masslesses clocks are expected to be gravity and motion insensitive.

http://tf.nist.gov/timefreq/cesium/parcs.htm
http://bigben.stanford.edu/sumo/status.htm
http://bigben.stanford.edu/sumo/

As for time...
It waits for no man, only women. ;-)

Sue...