Re: [LEAPSECS] how posterity will measure time

From: Rob Seaman <seaman_at_NOAO.EDU>
Date: Mon, 4 Dec 2006 11:29:01 -0700

On Dec 4, 2006, at 9:41 AM, Rob Seaman wrote:

> Any group of hunter-gatherers who stumble on WIPP and think to raid
> it as they will likely have been raiding landfills and other fin de
> millénaire treasure troves, will first have to pass the threshold
> of being capable of gaining physical entry. If they are skilled
> enough to do this, they are skilled enough to make some simple
> astronomical observations

I suppose I might comment on the implied leap second topic, too. No,
I don't think this particular issue overlaps much with UTC policy
questions. On the other hand, it is a good example of the
distinction between absolute and relative (interval) time
references. UTC as currently constituted (and universal time in
general) represents an absolute time reference keyed, as with the
WIPP signage, to astronomical observations. An amateur astronomer
with a Celestron, the Astronomical Almanac and an atlas can recover
UTC anywhere on Earth. An advanced amateur with the same telescope
and a slightly larger reference library could do so for the next few
thousand years. A dynamically trained astronomer could do so from
first principles and some boundary conditions obtained, for instance,
from archeology.

Unplug the atomic clocks for a few seconds (which may be taken as the
definition of a "discontinuity in higher civilization"), and even the
professional timekeepers who built the devices would be unable to
recover TAI.

Also, many amateur astronomers have designed and built their own
telescopes (and sundials). Even a tribe of hunter-gatherers could
afford their shaman enough free time to build a serviceable 'scope
assuming naked eye observations weren't sufficient. The instructions
could also be carved in granite if no issues of Sky&Telescope survive.

Building an atomic clock posits maintaining a continuously lofty
level of civilization indefinitely.

> One imagines the corpses of previous diggers will serve as an even
> better warning sign for the successive neolithic survivors of
> repeated discontinuities.

A "civilization" that affords freak show proprietors the opportunity
to display "plastinated" cadavers mimicking macabre everyday
activities might even more reasonably pre-position a few such
plasticized corpses for the purpose of preserving its descendants
from agony and a lingering death. Instead of Sagan's etched plaque
depicting friendly humans, include a tableau of friendly humans
themselves, complete with simulated pustules, vomit and blood
spurting from strategic orifices. The display's feng shui could be
modeled on the more heart-rending family scenes found at Pompeii.

Rob
Received on Mon Dec 04 2006 - 10:33:45 PST