[time-nuts] historical photos and info about Hafele-Keating

Tom Van Baak tvb at LeapSecond.com
Tue Jan 24 02:50:49 EST 2012

Hi Ben,

Thanks for the note. I had planned to meet Richard Keating when
I flew out to the east coast to present the results of my Mt Rainier
relativity experiment in 2005 but sadly he pass away just months
before the conference. Carroll Alley was there so I got to meet
him, which was a treat.

You can add links to both Dr. Alley's papers and to Dr. Vessot's
papers (gravity probe A). IIRC, they are all online. If not I have
copies here I can send you.

Here's a nice photo of a similar flying clock:
The clock is a hp 5060A (H&K used 5061A). The gentleman in
the foreground with his back to the camera is Len Cutler.

Given my particular interest in all this, over the years I've had
contact with a number of people involved with the development
of cesium and other atomic clocks or various traveling clock
experiments. A number of them are still alive.

Some other articles related to synchronizing clocks in the flying
clock years are:

A New Performance of the "Flying Clock" Experiment

Correlating Time from Europe to Asia with Flying Clocks

World-Wide Time Synchronization, 1966

'Flying Clock' Comparisons Extended to East Europe, Africa and Australia

I'll contact you more off-line about this. Meanwhile, thanks for
your posting.


----- Original Message ----- 
From: "Noneayour Bsnes" <pacificsymphony5 at yahoo.com>
To: <time-nuts at febo.com>
Sent: Monday, January 23, 2012 8:46 PM
Subject: [time-nuts] historical photos and info about Hafele-Keating

I teach physics, and I love the Hafele-Keating experiment as a way
to introduce relativity. Because the experiment has a lot of charisma, 
it's cool to be able to show students photos of the men and the
clocks aboard the plane. The general relativity text by Hartle had
a photo that he claimed was of Hafele and Keating boarding a plane,
but it turns out that that was a mistake. Some actual photos from
the experiment have been available online for a while, but they were
low resolution. I've obtained and scanned copies of these at higher
resolution and posted them here:

The copyright status of these photos varies, and in some cases is 
difficult to determine. I've given what information I had on the
web page. I'm in the U.S., where we have a pretty good fair use 
exception to copyright, and for the photos that are copyrighted,
I think I have an excellent fair-use claim.

I would be grateful to anyone who could e-mail me with any of the

-any biographical information about Hafele or Keating, and contact
information if they are still living

-related historical photos that are in the public domain and of high
educational or historical interest

-information about the copyright of the photo that appeared in
Popular Mechanics

Is anyone on this list old enough to have been involved in
relativistic atomic clock experiments from that era?


Ben Crowell

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