Mini-comet spotter?

In the 1990 book "The Big Splash" Dr. Louis A. Frank speculated that the
odd Noctilucent high-altitude clouds seen at polar latitudes in summer
were due to miniature dark-colored comets being disrupted as they hit
Earth's gravity field, and depositing ice crystals in the outer atmosphere.
If that's the case (not many think it is), then this could spot them:
http://www.nasa.gov/mission_pages/aim/index.html

Pat

Pat Flannery wrote:

In the 1990 book "The Big Splash" Dr. Louis A. Frank speculated that the
odd Noctilucent high-altitude clouds seen at polar latitudes in summer
were due to miniature dark-colored comets being disrupted as they hit
Earth's gravity field, and depositing ice crystals in the outer atmosphere.

That theory, after being presented, was viciously counterattacked
in the journals. Frank and coworkers went through remarkable gyrations
to try to explain away the contradictory evidence. I doubt anyone but Frank
believes it today, if even he does.

The general consensus, IIRC, is the evidence he used (UV imaging from
a satellite) was just artifacts from cosmic ray impacts on the detector.

Paul

Paul F. Dietz wrote:

That theory, after being presented, was viciously counterattacked
in the journals. Frank and coworkers went through remarkable gyrations
to try to explain away the contradictory evidence. I doubt anyone but
Frank
believes it today, if even he does.

The general consensus, IIRC, is the evidence he used (UV imaging from
a satellite) was just artifacts from cosmic ray impacts on the detector.

Though some covered multiple pixels.
Well, here's the chance to figure out whats actually going on.
Dr. Frank dreamed of a spacecraft like this, and although I also have
very hard time buying his mini-comets theory, here's an opportunity to
figure out exactly how those damn noctilucent clouds form.
I've seen one of those BTW; back when I was doing weather observation
work at Jamestown airport we had a section down at the base of our
weather observation form to give details of anything oddball we'd seen.
In my twelve years of working out there, the only really oddball thing I
saw, and noted in that section, was a strikingly brilliant noctilucent
cloud that appeared around an hour and a half before sunrise. Small in
size but very beautiful, it made me wonder if some artifact of a
Vandenberg launch hadn't floated over on the jet stream, as they had
launched something on a Titan IV two days before.
Theoretically, we were supposed to cross anything out we wrote in error
without erasing it, by drawing a horizontal line though it, and
continuing below.
After my fifth attempt to try to spell "noctilucent" without a
dictionary, the "white-out" started getting used.
Not strictly government standard, but I wanted to have them know what I
was talking about.

P.S. After years of effort, I have actually learned that "Satellite" is
spelled that way, and not "Sattelite", "Sattilite", or "Sattellite".
I consider this a major victory, ranking right up there with the correct
spelling of "vacuam".

Pat

On Fri, 6 Apr 2007 09:15:13 -0500, Pat Flannery wrote
(in article ):


P.S. After years of effort, I have actually learned that "Satellite" is
spelled that way, and not "Sattelite", "Sattilite", or "Sattellite".
I consider this a major victory, ranking right up there with the correct
spelling of "vacuam".

Yes, but how do you spell nookyaler? ;-)

--
You can run on for a long time,
Sooner or later, God'll cut you down.
~Johnny Cash

Pat Flannery wrote:
In the 1990 book "The Big Splash" Dr. Louis A. Frank speculated that the
odd Noctilucent high-altitude clouds seen at polar latitudes in summer
were due to miniature dark-colored comets being disrupted as they hit
Earth's gravity field, and depositing ice crystals in the outer atmosphere.
If that's the case (not many think it is), then this could spot them:
http://www.nasa.gov/mission_pages/aim/index.html

Pat

I subscribe to David Brin's cometary model: If outgassing is gradual
enough, an insulating mantle accumulates which slows more and more the
loss of inner volatiles.

(While Brin is better known as a science fiction writer, he used to be a
planetary scientist. His model of cometary evolution was his doctoral
thesis.)

The smaller the comet, the greater the surface to volume ratio, and the
tinier the gravity. I believe a miniature comet would have a miniature
life span.

So I'm skeptical of Frank's theory.

Hop

Pat Flannery wrote:


P.S. After years of effort, I have actually learned that "Satellite" is
spelled that way, and not "Sattelite", "Sattilite", or "Sattellite".
I consider this a major victory, ranking right up there with the correct
spelling of "vacuam".

I still have trouble with "tessellation" and "parallel".

(running spell checker . . . Heh! "Flannery" is the only objectionable
word.)

Hop

Pat Flannery wrote:
P.S. After years of effort, I have actually learned that "Satellite" is
spelled that way, and not "Sattelite", "Sattilite", or "Sattellite".
I consider this a major victory, ranking right up there with the correct
spelling of "vacuam".

Pat


I ran this through my favorite spell checker:

vacuam - no
vaaculum - no
vacum - no
vaccum - no

A void, typically in outer space, that sucks. - ok
A void, sometimes between one's ears, that sucks. - ok

;-)

Dave

Herb Schaltegger wrote:

Yes, but how do you spell nookyaler? ;-)


Just the way it sounds.

George W. Bush
The President Of The United States Of America

Hop David wrote:

I subscribe to David Brin's cometary model: If outgassing is gradual
enough, an insulating mantle accumulates which slows more and more the
loss of inner volatiles.

(While Brin is better known as a science fiction writer, he used to be
a planetary scientist. His model of cometary evolution was his
doctoral thesis.)

The smaller the comet, the greater the surface to volume ratio, and
the tinier the gravity. I believe a miniature comet would have a
miniature life span.

His mini-comets were a couple of hundred feet wide maximum; basically a
pile of snowflakes covered with a thin black crust.
To me, the big hole in his theory is that one of these hitting the
atmosphere should have generated a meteor shower like you've never
seen... a whole pile of meteors coming from one point in the sky in a
split second. He never did explain how the whole thing could come apart
into so fine of particles that none would heat up on hitting the
atmosphere, given that particles the size of a grain of sand can
generate quite a flash on the way down.
Anyway, the book was a fun read, and I applaud him for thinking outside
the box. Even he was having a hard time buying his own theory by the end.

Pat

Hop David wrote:
.

I still have trouble with "tessellation"

What the hell is that? Sounds like something to do with high voltage
electricity.
Ranks right up there with the time David Sander dropped "valsalva" on me
out of the blue.

Valsalva (n.)
1.) Forked rubber device used to close the nose in a Apollo space helmet
so that one may generate back pressure against the inner ear during
shifts in air pressure.
2.) One of the lesser dwellings of the Norse heroes; traditionally
located directly to the north of Asgard's brewery.
3.) Minor female character in Henry Miller's "The Tropic Of Climaxes";
traditionally located directly to the north of a Parisian lamppost.

and "parallel".

Garuntee gets me also.


(running spell checker . . . Heh! "Flannery" is the only objectionable
word.)

I'm sure Rand Simberg would agree.

Pat