[X] My Assistant

[ljk4-1]

The suggestions put forth by Mr Richard Trigaux are mostly interesting possibilities, and I agree that the cost for interstellar flight -even for one extremely advanced civilization- would be so high that it possibly would take some kind of 'grand idea' of one kind or other before they would undertake and well open the wallet for the tremendous cost.

But I would be hard pressed to accept the idea of any kind of civilization that would mine minerals in one stellar system and then ship the metals over interstellar distances.
There might be need for mining for one species that travel between the stars, perhaps for repairing the ship or possibly replace eroded radiation shields. But that would of cource be rather limited.
Galactic construction project? You placed your bets on the arrival of the Vogon construction fleet? 

Here is another reason for interstellar travel, the concept known as The Project developed by Dr. Steven Kilston of Ball Aerospace and Technologies Corporation.

The attached slides are from a presentation he gave on the subject at JPL in 1999.

The multigenerational starship bears an awfully strong external resemblance to Rama.

“Man is an artifact designed for space travel. He is not destined to remain in his present biologic state any more than a tadpole is destined to remain a tadpole.”

- William Burroughs

Attached File(s)

 TheProject.pdf ( 645.8K ) Number of downloads: 5831

 

[ljk4-1]

Paper: astro-ph/0601356
Date: Tue, 17 Jan 2006 02:18:41 GMT (947kb)

Title: Introduction: Paleoheliosphere versus PaleoLISM

Authors: Priscilla C. Frisch

Comments: The article will appear in the book "Solar Journey: The Significance
of Our Galactic Environment for the Heliosphere and Earth", Springer, in
press (2006), editor P. C. Frisch
\\
Speculations that encounters with interstellar clouds modify the terrestrial
climate have appeared in the scientific literature for over 85 years. This
article introduces a series of articles that seek to give substance to these
speculations by examining the exact mechanisms that link the pressure and
composition of the interstellar medium surrounding the Sun to the physical
properties of the inner heliosphere at the Earth.

\\ ( http://arXiv.org/abs/astro-ph/0601356 , 947kb)

------------------------------------------------------------------------------

Paper: astro-ph/0601359
Date: Tue, 17 Jan 2006 03:30:06 GMT (848kb)

Title: Short-term Variations in the Galactic Environment of the Sun

Authors: Priscilla C. Frisch and Jonathan D. Slavin

Comments: The article will appear in the book "Solar Journey: The Significance
of Our Galactic Environment for the Heliosphere and Earth", Springer, in
press (2006), editor P. C. Frisch
\\
The galactic environment of the Sun varies over short timescales as the Sun
and interstellar clouds travel through space. Small variations in the dynamics,
ionization, density, and magnetic field strength of the interstellar medium
(ISM) surrounding the Sun yield pronounced changes in the heliosphere. We
discuss essential information required to understand short-term variations in
the galactic environment of the Sun, including the distribution and radiative
transfer properties of nearby ISM, and variations in the boundary conditions of
the heliosphere as the Sun traverses clouds. The most predictable transitions
are when the Sun emerged from the Local Bubble interior and entered the cluster
of local interstellar clouds flowing past the Sun, within the past 140,000
years, and again when the Sun entered the local interstellar cloud now
surrounding and inside of the solar system, sometime during the past 44,000
years.

\\ ( http://arXiv.org/abs/astro-ph/0601359 , 848kb)

------------------------------------------------------------------------------

Paper: astro-ph/0601357
Date: Tue, 17 Jan 2006 02:45:13 GMT (306kb)

Title: Pulsar rotation measures and the large-scale structure of Galactic
magnetic field

Authors: J.L. Han (NAOC), R.N. Manchester (ATNF), A.G. Lyne (Jodrell Obs), G.J.
Qiao (PKU), W. van Straten (UTB)

Comments: ApJ accepted. 16 pages, 14 figures, 2 tables, 223 pulsar RMs
\\
The large-scale magnetic field of our Galaxy can be probed in three
dimensions using Faraday rotation of pulsar signals. We report on the
determination of 223 rotation measures from polarization observations of
relatively distant southern pulsars made using the Parkes radio telescope.
Combined with previously published observations these data give clear evidence
for large-scale counterclockwise fields (viewed from the north Galactic pole)
in the spiral arms interior to the Sun and weaker evidence for a
counterclockwise field in the Perseus arm. However, in interarm regions,
including the Solar neighbourhood, we present evidence that suggests that
large-scale fields are clockwise. We propose that the large-scale Galactic
magnetic field has a bisymmetric structure with reversals on the boundaries of
the spiral arms. Streaming motions associated with spiral density waves can
directly generate such a structure from an initial inwardly directed radial
field. Large-scale fields increase toward the Galactic Center, with a mean
value of about 2~$\mu$G in the Solar neighbourhood and 4~$\mu$G at a
Galactocentric radius of 3 kpc.

\\ ( http://arXiv.org/abs/astro-ph/0601357 , 306kb)

[Guest_AlexBlackwell_*]

Forgive me for asking, but what do any of these three preprints, interesting though they might be, have to do with the topic of the thread (viz., "Seti And Particularly Seti@home...")?

[ljk4-1]

They are an examination of how the galactic environment interacts with Earth and Sol. This will give us some idea of what conditions may be like elsewhere and how life might be affected by such interactions. This adds parameters to the possibility of life elsewhere, including the kind that might be found by SETI.

Perhaps I should have put this in your recent Astrobiology thread (thank you for the alert, BTW).

[Guest_AlexBlackwell_*]

That's stretching it, I think The structure of the board, however, often makes it hard to place notices of papers in topical threads.

Having said that, I'm not complaining. I do appreciate the heads-up on the arXiv preprints. I used to run daily searches on the LANL server and post interesting papers in my Yahoo! planetary_sciences group. So, when someone else (you, for instance) does the hard work, far be it from me to look a gift horse in the mouth.

[Guest_Myran_*]

AlexBlackwell said: Forgive me for asking, but what do any of these three preprints, interesting though they might be, have to do with the topic of the thread (viz., "Seti And Particularly Seti@home...")?

I agree we're somewhat off topic here, yet the question if one alien species would consider it worth the effort of undertaking interstellar journeys can have a consequence for SETI. Civilisations that colonize new worlds will be easier to find compared to if they only are found on a single planet.

[ljk4-1]

That's stretching it, I think    The structure of the board, however, often makes it hard to place notices of papers in topical threads.

Having said that, I'm not complaining.  I do appreciate the heads-up on the arXiv preprints.  I used to run daily searches on the LANL server and post interesting papers in my Yahoo! planetary_sciences group.  So, when someone else (you, for instance) does the hard work, far be it from me to look a gift horse in the mouth.

People rightly complain to a degree that there is a lacking of data in certain areas in SETI; well, when I find something scientifically substantial that helps to narrow down the possibilities for life beyond Earth, posting that data is important.

That said, I am sure I speak for everyone here when I say I am also grateful for your hard work in finding papers to post here. This site has become a valuable online library for astronomy and space science.

[ljk4-1]

I agree we're somewhat off topic here, yet the question if one alien species would consider it worth the effort of undertaking interstellar journeys can have a consequence for SETI. Civilisations that colonize new worlds will be easier to find compared to if they only are found on a single planet.

And of course why leave us with the paradigm that ETI with advanced technology would resign themselves to a planet:

http://en.wikipedia.org/wiki/O'Neill_habitat

http://www.futurehi.net/docs/Matrioshka_Brains.html

[dvandorn]

It's been asked, why would you want to try and develop a civilization capable of moving from one star system to another -- or perhaps, from one galaxy to another? These would be Kardyshev Type 3 civilizations, if I recall correctly.

One reason I can think of is that the Milky Way may well be doomed. Anyone living in about 60% to 70% of the galaxy can plainly see that M31 is heading straight for us, and that our two galaxies will collide in about 3 or 4 billion years.

We don't yet know if such a collision will have a really deleterious effect on the habitability of currently habitable planets in this galaxy. But perhaps the odds are good that most of us will be wiped out when the galaxies collide.

And that any sufficiently advanced ETI has deduced this. And has moved completely out of the doomed Milky Way -- perhaps to stars within the Magellanic Clouds, perhaps to a more distant galaxy not in quite so iminent danger of collision.

I know, it's a pretty far-out reason for the lack of advanced ETI in the Milky Way -- but it *is* a viable one.

-the other Doug

[ljk4-1]

It's been asked, why would you want to try and develop a civilization capable of moving from one star system to another -- or perhaps, from one galaxy to another?  These would be Kardyshev Type 3 civilizations, if I recall correctly.

One reason I can think of is that the Milky Way may well be doomed.  Anyone living in about 60% to 70% of the galaxy can plainly see that M31 is heading straight for us, and that our two galaxies will collide in about 3 or 4 billion years.

We don't yet know if such a collision will have a really deleterious effect on the habitability of currently habitable planets in this galaxy.  But perhaps the odds are good that most of us will be wiped out when the galaxies collide.

And that any sufficiently advanced ETI has deduced this.  And has moved completely out of the doomed Milky Way -- perhaps to stars within the Magellanic Clouds, perhaps to a more distant galaxy not in quite so iminent danger of collision.

I know, it's a pretty far-out reason for the lack of advanced ETI in the Milky Way -- but it *is* a viable one.

-the other Doug

When our Milky Way and the Andromeda galaxy do collide, around the time our Sun is turning into either a red giant or shrinking to a white dwarf (I've read it may not happen until about 6 billion CE), there will likely be very few actual collisions with stars from either galaxy, due to the wide spaces between them.

However, many star systems may be flung out into the intergalactic void due to gravitational interactions. Plus the interacting dust and gas will likely create new stars as well. And if there are ETI in the Andromeda galaxy, we'll also have new neighbors - whether we want them (or they us) or not.

Perhaps one or all of these events will be the motivation to move. But to where by then is the question. Will the Magellanic Clouds even exist? I have not looked into how close or far other currently nearby larger galaxies will be by then. Or maybe those distant societies will find a way to exist without needing to be in a galaxy.

This paper actually discusses where one might go beyond the galaxy:

http://www.unmannedspaceflight.com/index.php?showtopic=1653


These two HST sites show an artist's representation and video of what the galactic merger may look like from Earth:

http://hubblesite.org/newscenter/newsdesk/.../1997/34/image/

http://hubblesite.org/newscenter/newsdesk/...1997/34/video/c


Other references and computer animations of the galaxy mergers:

http://www.space.com/scienceastronomy/astr...s_020507-1.html

http://www.newsandevents.utoronto.ca/bin/000414b.asp

http://www.galaxydynamics.org/

[ljk4-1]

RELEASE: 06-03AR

NASA AMES CENTER DIRECTOR JOINS SETI INSTITUTE

G. Scott Hubbard, director of NASA Ames Research Center, located in California's Silicon Valley, today announced that he has accepted a new position as the Carl Sagan Chair for the Study of Life in the Universe at the SETI Institute in Mountain View, Calif., effective Feb. 15, 2006.

As holder of the Carl Sagan Chair, Hubbard will work to strengthen the SETI Institute's capability, visibility and support for its research into the origin of life, and how it might be found on other worlds, in the planets and moons of our solar system or beyond.

"The people at Ames are among the best in the agency, and it has been both a pleasure and an honor to serve as the Ames center director. I know Ames will continue to play a creative and critically important role in NASA's programs," Hubbard said. "My new position at the SETI Institute allows me to return to the research arena and pursue a lifelong interest in the search for life in the universe and its origins on Earth. I believe this field, which is often called astrobiology, is both the scientific heart of the exploration vision and the most exciting area of research today. We have a chance to learn things that, only a generation ago, would have seemed beyond our capabilities," he added.

"Scott is the perfect candidate for the Carl Sagan Chair," remarked Thomas Pierson, chief executive officer of the SETI Institute. "He has a solid background in the relevant sciences and has proven himself to be an effective and widely admired leader. As the holder of the Carl Sagan Chair, Scott will be engaged with many audiences, furthering their understanding about science and its potential for new discoveries. Scott will bring both expertise and enthusiasm to this task and will be a terrific representative for the Institute both domestically and internationally," Pierson added.

Hubbard began his career at NASA Ames in 1987, and has served as the center director since 2002, accumulating numerous awards and honors along the way. He is known for his innovative approach to collaborations between government, academia and the private sector, particularly as embodied by the development of the award-winning NASA Research Park, research collaborations with Google Inc., and the creation of the Project Columbia supercomputer, one of the world's fastest.

His many accomplishments include his work on the Columbia Accident Investigation Board, which helped to establish the physical cause of the loss of the space shuttle Columbia. His tenure as the first NASA Mars program director redefined NASA's robotic Mars missions and led to the successful and ongoing reconnaissance of Mars by the Mars Exploration Rovers. He served as the manager for the Lunar Prospector mission that found water ice at both of the moon's poles, and he is credited with conceiving the Mars Pathfinder mission. As center director, he managed NASA Ames through a critical transition to better align the center's capabilities with the Vision for Space Exploration, resulting in the award of the management of the Robotic Lunar Exploration Program. Hubbard also served as the first director of NASA's Astrobiology Institute.

NASA Ames Research Center specializes in research geared toward creating new knowledge and new technologies that span the spectrum of the agency's missions and interests, with a focus on the Vision for Space Exploration.

The SETI Institute is a non-profit research organization addressing the broad question of life in the universe. It is home to many dozens of scientists engaged in investigating the origin, nature and distribution of life. Its board of trustees includes many eminent scientists, including two winners of the Nobel Prize, as well as numerous academics and technology innovators.

Additional information about NASA Ames and the SETI Institute is available on the Internet at:

http://www.nasa.gov/centers/ames/home/index.html

http://www.seti.org

[ljk4-1]

The Ultimate SETI Signal

Robert Carrigan (Fermi National Accelerator Laboratory) drew quite a bit of attention last summer when he suggested that SETI signals could contain harmful information, perhaps created by a so-called ‘SETI hacker.’ Carrigan’s article has now appeared in Acta Astronautica, and it’s stuffed with beguiling ideas even if you find the premise unlikely.

“…will a SETI signal be altruistic, benign or malevolent?” Carrigan asks. “It would help to understand the motivations of a message before reading too much of it. Like Odysseus, we may have to stuff wax in the ears of our programmers and strap the chief astronomer to the receiving tower before she is allowed to listen to the song of the siren star.”

...

“The most important point is that large amounts of information can be transferred inexpensively at the speed of light even with current technologies. In addition, the message size can easily be so large that the underlying intent of the message would not be apparent.”

The paper, which belongs on the shelves of disks of anyone following the SETI search, is “Do potential SETI signals need to be decontaminated?” in Acta Astronautica 58 (2006), pp. 112-117.

Carrigan’s own site contains earlier work on the theory:

http://home.fnal.gov/~carrigan/SETI/SETI_Hacker.htm

The full Centauri Dreams article is here:

http://www.centauri-dreams.org/?p=522

[Guest_Richard Trigaux_*]

The Ultimate SETI Signal

Robert Carrigan (Fermi National Accelerator Laboratory) drew quite a bit of attention last summer when he suggested that SETI signals could contain harmful information, perhaps created by a so-called ‘SETI hacker.’ Carrigan’s article has now appeared in Acta Astronautica, and it’s stuffed with beguiling ideas even if you find the premise unlikely.

“…will a SETI signal be altruistic, benign or malevolent?” Carrigan asks. “It would help to understand the motivations of a message before reading too much of it. Like Odysseus, we may have to stuff wax in the ears of our programmers and strap the chief astronomer to the receiving tower before she is allowed to listen to the song of the siren star.”

...

“The most important point is that large amounts of information can be transferred inexpensively at the speed of light even with current technologies. In addition, the message size can easily be so large that the underlying intent of the message would not be apparent.”

The paper, which belongs on the shelves of disks of anyone following the SETI search, is “Do potential SETI signals need to be decontaminated?” in Acta Astronautica 58 (2006), pp. 112-117.

Carrigan’s own site contains earlier work on the theory:

http://home.fnal.gov/~carrigan/SETI/SETI_Hacker.htm

The full Centauri Dreams article is here:

http://www.centauri-dreams.org/?p=522

I think this is perfectly right, if an alien SETI catches our emissions, they will have to be very cautious, not to be muddled by some psychology trick, between reality shows, politic or religious propaganda, election promises and "realistic politics", revisionisme, etc.

[ljk4-1]

Send a message to 47 Ursae Majoris:

http://www.cosmicconnexion.com/static/index.html

Apparently this exercise in Active SETI (ASETI) is the "celebration"
part of the COROT astronomy satellite mission to find extrasolar
planets, including Earth-size (Telluric) ones. COROT is set for
launch in June of 2006.

http://smsc.cnes.fr/COROT/

http://www.esa.int/science/corot

http://cfa-www.harvard.edu/planets/corot.html


Not that we should refine our ETI searches just to planets
(some would argue we will have better chances aiming our
telescopes at regions which show up in the infrared but not
the optical), but 47 UM does have at least two Jupiter-class
worlds orbiting at fairly large distances from their star (unlike
all those other exogiants that practically skim the photospheres),
allowing at least the possibility of an Earth-size world in the
habitable zones.

See here:

http://www.solstation.com/stars2/47uma.htm

Will the messages being sent out by CNES "survive" the 46 light year
journey to 47 UM? Will they even be comprehensible to anyone
there? Will it at least let any ETI present know they are not alone
and motivate them to respond? Is it wiser to keep our mouths
shut and let someone else contact us first? Or do we gain nothing
by hiding under our beds - except dust?

[ljk4-1]

MONDAY, FEBRUARY 6, 2006 on the National Geographic Channel

Naked Science: "Alien Contact" at 9P et/pt

Are we the only intelligent species in the universe? Find out why
some scientists are convinced we're on the verge of finding other
life forms as we separate scientific fact from science fiction in
the search for extraterrestrials.

Visit the National Geographic Channel home page.

http://ng.chtah.com/a/tBD55y6ASJ4TXAcfOn6A...R.ASJ-ROYQ/ngs6