You wrote;
> A quick question. My uncle tells me that one of the early space
> programs rockets had a clock on board and an identical clock that
> remained on the Earth. When the capsule returned, the clocks were
> off. Did they actually do this? Thanks for your time (no pun)
> Ron Nakano - rmm@mako.com
I don't know about that specific experiment, though I hear the use of
atomic clocks, using the oscillations from a cesium atom I believe tend
to show anomalies from planes flying high in the atmosphere and clocks
on the planet.
I couldn't find anything on the web that specifically states such an
anomalous response, so treat it as hearsay..the folks to ask would be
NASA direct.
I did a search and found this on atomic clocks (but I'm pretty sure
cesium is also used, could be any atom really);
How atomic clocks work;
http://www.iao.com/howthing/atomihtw.htm
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A good document about why atomic clocks are necessary and indicating no
variations from earth orbit to earth;
http://www.nextstep.com/stepback/cycle10/123/atomic.html
======================
Your computer time versus atomic clock time;
http://www.tomjaffe.com/clockb.htm
A much superior comparison page;
http://www.rickmandata.com/time/cst.htm?
======================
The atomic clock as a phase stable oscillator for DEEP SPACE
COMMUNICATION;
http://bul.eecs.umich.edu/uffc/fc_abstracts/abstract7-15-156.html
======================
Atomic clock in space to reach new heights of accuracy (cesium);
http://www.af.mil/news/Jan1998/n19980120_980077.html
The projected accuracy of the space clock will be at least 10 times
better than the best Earth-based clocks. The accuracy of Earth-bound
cesium atomic clocks is limited by the length of time each cesium atom
can be observed -- on Earth; gravity quickly removes the atoms from the
observation region. In the microgravity environment of space, each atom
can be observed for many seconds. The space clock will enable
researchers to make gravitational red-shift measurements, test whether
the speed of light is truly the same in all directions, and do other
relativity experiments.
======================
Fascninating page on radiation and space induced equipment anomalies;
http://envnet.gsfc.nasa.gov/Papers/JPRadiation.html
Single-event upset rates in complex devices such as microprocessors, or
latchups or burnouts in any device, cannot be reliably predicted.
Educated guesses based on accelerator observations and study of the
flight performance of similar devices is a common procedure.
Galactic cosmic rays can also generate background noise in star sensors,
infrared detectors, and charge coupled devices. In addition to noise,
these rays can masquerade as real signals which may affect subsystems.
Nichols [6] ranks the hardness of current technologies as shown in Table
1. He also notes that P-Type Metal-Oxide Silicon (PMOS) is susceptible
to SEUs. In all of these devices depositing charge at a certain point in
the circuit is equivalent to changing the voltage at the point.
======================
You might send an inquiry about this rocket/clock anomaly claim to
NASA's home page;
and here is how to contact them (maybe they'll answer..<g>..);
http://www.nasa.gov/hqpao/comments.html
or the Jet Propulsion Laboratory;
-- Jerry Wayne Decker / jdecker@keelynet.com http://keelynet.com / "From an Art to a Science" Voice : (214) 324-8741 / FAX : (214) 324-3501 KeelyNet - PO BOX 870716 - Mesquite - Republic of Texas - 75187