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Dave Dietzler wrote:Here's a copy of my message sent to Peter Kokh.
He likes to know what we're up to.
Forwarded Message |
Date: |
Wed, Nov 9, 2005 |
From: |
Dave Dietzler" |
Subject: |
Moon Society Meeting 11/9 |
To: |
Peter Kokh, MMM |
We had some stimulating discussion tonight that took off when we we started
talking about extremophiles. This lead to some discussion about hot Jupiters.
Of the small percentage of stars monitored for exoplanets, most have hot
Jupiters. This doesn't bode well for Earth type planets but the possibility
of rogue planets tossed out by these hot Joves increases. Since Greek myth
says that an angry Jove tossed Hephaestus (Vulcan in the Roman tongue, also
Mulciber in other languages) from Olympus and he fell for nine days like an
anvil from the sky, perhaps we could call some of these rogue worlds, should
they exist, Vulcanoids or Mulcibers. Since Vulcanoid has already been taken
for worlds closer than Mercury, perhaps Mulcibers...
It seems that of the small percentage of G-type suns studied, most have hot
Jupiters. One argument was put forth that the technique is most sensitive to
this kind of world. Another argument was made that of those stars studied almost all had hot-Js, thus it's sort of like a Gallup poll. If 5% are asked who do you want to vote for and most say Mr. J, then it's likely that most voters will pick Mr. J. Whether or not sky surveys are like a random sample based poll I do not know. It looks to me now that solar systems like ours are rare. I'm not fully certain what's going on. I haven't seen the stats.
I had discounted the possibility of life around red dwarfs which compose 80%
of the stars in the galaxy, but heard some good news.
1) |
Though the life zone near a red dwarf is
narrow, there are so many red dwarfs that the chances of a planet in
our galaxy being in the life zone is as high as a planet being in the
wider life zone of our less common type of Sun. |
2) |
Many red dwarfs give off x-ray flares with
an x-ray intensity over 100,000 times that of a flare on our Sun; however,
after a billion years these stars settle down. |
3) |
Although a planet in the life zone of a red
dwarf will probably be tidally locked, atmospheric circulation between
the sun side and dark side is posssible. |
I can only add:
A) |
The life zone might be wider than we think.
After discussing extremophiles I don't doubt that it is. |
B) |
Can't beat those x-rays but there is a
bacterium called radiodurans that has amazing radiation resistance
because it has so many copies of its own DNA. Also, life can evolve
underwater and underground, shielded from x-rays. Finally, there
wasn't much life on Earth during its first billion years and metazoic
life as well as most species have evolved in the past 550 million years.
Before that there were just protozoans for billions of years. |
C) |
Circulation between sun side and night side
seems plausible to me. Venus is almost tidally locked and there are winds
that circle the planet every four days. |
Imagine intelligent life on a tidally locked world evolving on the sun
side and eventually exploring the dark side and seeing the stars for the
first time! What if life on other worlds did get out of the single celled
stage earlier than life on Earth did? There could be advanced species
billions of years older than advanced multicelluar species on Earth.
Many could already be extinct.
Some bacteria have purple chlorophyll. Unlike green chlorophyll that
is most sensitive to yellow light at 540 nm as well as some red and blue
light, while it reflects green light (that's why you can grow plants under
red and blue LEDs but not green lamps, folks), purple chlorophyll is
sensitive to red and infrared light at about 1000 nm. Could life on worlds
orbiting red dwarfs be based on purple chlorophyll? What unusual sights
that would leave to be seen. Worlds bathed in reddish light covered with
purple vegetation...Purple chlorophyll can make glucose but not oxygen;
however, not all life on Earth needs oxygen. Water seems to be the common
denominator.
Finally, could there be life on worlds orbiting hot Jupiters? Earth type
planets orbiting a hot-J or even a hot Saturn with rings...what incredible
sky sights those would be!! Or Europas and Ganymedes with oceans. At the
right distance, might a Jovian moon form a water vapor atmosphere that had
enough pressure to keep water liquid, or as ice? Ice reflects much light.
Perhaps with the right orbital dynamics a Europa would warm up on the sun
side and cool down when eclipsed by the giant planet it orbits to stay in
equilibrium and not loose its oceans or ice covered oceans for billions of
years. If such worlds exist, and we do too in the future, I know where the
editor of MMM is to be found!
Dave Dietzler
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Chris Nobbe wrote: |
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Now I know what was discussed at the
meeting - sorry I missed it.
Chris |
Chris,
Dave hit some of the highlights - there was even more. I should
have CC'd everyone when I replied
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David Heck wrote: |
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Sounds like I missed a good meeting...
Who all was there ?? |
Dave, |
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Yup, we'ns set roun' da pickle barrel
an whittled an jawed.
Me, Burt Sharpe, David Dietzer, and Keith Wetzel.
Bob Perry
P.S. I mentioned that I'd seen
http://enterpriseforum.mit.edu/network/broadcasts/200509/
on NASA TV - carbon nanotube cable for a space elevator,
research on extremeophiles, designing future space suits.
That kicked it off and we just talked about all kinds of things.
I wish I'd recorded it!
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Yes, we really had a good round table discussion that just went on and on.
Dave Dietzer has covered hot Jupiters and touched on extremeophiles.
I'll try to recall some more of the things discussed.
carbon nanotubes for a cable
for a space elevator / skyhook
OK, buckminsterfullerene was discovered a few years ago - C60 is the
simplest one. The molecule is something like a sheet of graphite
warped back onto itself into a spherical shape, and the carbon atoms
are in a pattern of rings, either five or six to a ring, just like
the patches of leather of a soccer ball. Buckminster Fuller
is famous for the geodesic sphere and the C60 molecule is the smallest
possible geodesic sphere made from carbon. Not surprisingly, they
can be bigger and the real kicker is that they can occur as cylinders
where the hemispheric end caps are halves of buckminsterfullerene and
the cylindrical skin is a sheet of graphite rolled back to itself. And
they can be layered like Matryoshka (Russian Nesting Dolls), achieving
bizare properties. When a viable technique gets them out of the laboratory
and into the real world, civil engineering will go through an unprecedented
change - their tensile strength to weight ratio is insane.
research on extremeophiles - bacteria that live in extreme environments
They're everywhere, they're everywhere. They make black smokers possible,
they make hot springs colorful, they live inside frozen rocks at the dry valley
near the south pole and in the rocks of the deepest, hottest mines. We
had a quick digression wondering if silicon, one row down from carbon in the
perodic table, could be the basis of life somewhere in the universe. Well,
science fiction has given us the beserkers and the cylons and that got us onto
Fermi's Question:
A generation back, the Orion project led to the British Interplanetary Society
proposing several interesting techniques for traveling to the stars. It can
be argued that the human race just might do that. Then whatever daughter colonies
are established out there, they could, in perhaps three or four generations, send
out their own colony ships, plural. If Earth seeds at least two, and they do
at least two each, and each of them . . . well, geometric progression really takes
off. So, in a geologically short period of time, the human race could spread
throughout our galaxy. OK, if our solar system is about five billion years old,
with a third generation star, couldn't a slightly older third generation star have
already done the same thing? Or even a second generation star? If so,
"Where is everybody?" Maybe Star Trek's Prime Directive has been applied.
But then again, the inverse of Fermi's Question is, "Are we the elder race?"
designing future space suits
Sorry to say, this got little discussion. But we briefly talked about one
segment of the "science of Star Wars" 'documentary'. NASA has funded research
into telepresence and, since the atmosphere in the space station and that used in the
space suits are so disparate, suitup time (aclimation) is significant. 'Robonaut'
might be the answer. Start with something like virtual reality and then include
interaction with the real world using force feedback end effectors / manipulators,
stereo vision, and appropriate power supply and locomotion. Robonaut could just
wait outside the airlock and then be called to action as quickly as the roboteer can
wrap himself in telepresence reality.
Dave Dietzer mentioned in another of his emails that such a good discussion is
invigorating and that the club should consider hosting a major event. I agree.
Let's get a flurry of emails going and plan something.
Bob Perry
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