Space: What's out there

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Sun, 2009-02-15 10:42

NorthReport

Space: What's out there

Galaxy has 'billions of Earths'

There could be one hundred billion Earth-like planets in our galaxy, a US conference has heard.

Fomalhaut star and exoplanet (AFP/Getty) The number of stars points to there being many rocky planets

http://news.bbc.co.uk/2/hi/science/nature/7891132.stm?lss

But, based on the limited numbers of planets found so far, Dr Boss has estimated that each Sun-like star has on average one "Earth-like" planet.

This simple calculation means there would be huge numbers capable of supporting life.

"Not only are they probably habitable but they probably are also going to be inhabited," Dr Boss told BBC News. "But I think that most likely the nearby 'Earths' are going to be inhabited with things which are perhaps more common to what Earth was like three or four billion years ago." That means bacterial lifeforms.

Dr Boss estimates that Nasa's Kepler mission, due for launch in March, should begin finding some of these Earth-like planets within the next few years.

Recent work at Edinburgh University tried to quantify how many intelligent civilisations might be out there. The research suggested there could be thousands of them.

Sun, 2009-02-15 11:13

remind

The "wraith". ;)

And his view is very this earth centric, if not adhering to "Biblical" pronunciations, why would there be only "bacteria" on other planets.

Sun, 2009-02-15 11:22

Unionist

remind wrote:

... why would there be only "bacteria" on other planets.

Your viewpoint seems rather complex-lifeform-centric. What's wrong with being a bacterium? They've survived a lot longer than your species has.

Sun, 2009-02-15 11:27

Agent 204

The reason for saying that is that the step from prokaryotes (bacteria and archaea) to eukaryotes (plants, animals, fungi, etc) is thought to be a very big step, comparable to the emergence of life itself. The fossil record shows that prokaryotes were around for at least a billion years before the first eukaryotes appeared, so it's not unreasonable to suppose that most life-bearing planets would only have organisms resembling bacteria, and only a handful would have moved beyond that.

Sun, 2009-02-15 14:55

NorthReport

This is indeed very exciting as I thought most scientists had basically given up on finding life apart from our planet earth. Maybe that was intelligent life. Boss just gives us another 100,000 years here so we better hurry up our space exploration.

AAAS: 'One hundred billion trillion' planets where alien life could flourishThere could be one hundred billion trillion Earth-like planets in space, making it "inevitable" that extraterrestrial life exists, according to a leading astronomer.

http://www.telegraph.co.uk/scienceandtechnology/science/space/4629672/AAAS-One-hundred-billion-trillion-planets-where-alien-life-could-flourish.html

By Richard Alleyne, Science Correspondent in Chicago
Last Updated: 12:05PM GMT 15 Feb 2009

View of planet earth - 'One hundred billion trillion' planets where alien life could flourish Dr Alan Boss, of the Carnegie Institution in Washington DC, said there could be as many Earths as there are stars in the universe Photo: REUTERS

Life on Earth used to be thought of as a freak accident that only happened once.

But scientists are now coming to the conclusion that the universe is teeming with living organisms.

The change in thinking has come about because of the new belief there are an abundant number of habitable planets like Earth.

Alan Boss, of the Carnegie Institution in Washington DC, said there could be as many Earths as there are stars in the universe - one hundred billion trillion.

Because of this, he believes it is "inevitable" that life must have flourished elsewhere over the billions of years the universe has existed.

"If you have a habitable world and let it evolve for a few billion years then inevitably some sort of life will form on it," said Dr Boss.

"It is sort of running an experiment in your refrigerator - turn it off and something will grow in there.

"It would be impossible to stop life growing on these habitable planets."

He believes his views will be proved by NASA's Kepler outer space-based telescope, which takes off in the next three weeks with a mission to track down Earth-like habitable planets.

Within four years Dr Boss, who was speaking at the American Association for the Advancement of Science meeting, believes it will have found one in our galaxy and that will prove his theories about their abundance.

He then would like researchers to build even bigger telescopes and send out an unmanned spacecraft to take photographs of the distant planet that could be up to 30 light years away. It would, however, take at least 2,000 years to report back.

Dr Boss said: "We already know enough now to say that the universe is probably loaded with terrestrial planets similar to the Earth," he says.

"We should expect that there are going to be many planets which are habitable, so probably some are going to be inhabited as well."

Whether the life we find is intelligent is, however, less than inevitable.

"Intelligent life seems to be fleeting," he said. "In terms of the universe it only exists for a fraction of time."

He said it would be a massive coincidence for us to find intelligent life that exists at the same time as us. It is more likely to be bacteria or microbes.

"It is unlikely that 'we' will exist for a further 100,000 years," he said.

Sun, 2009-02-15 15:06

M. Spector M. Spector's picture

This is old news.

We've been reading stories like this since the 1970's.

The term "Earth-like" is very vague and misleading. Any planet that is truly like ours would almost certainly, given enough time, evolve intelligent life.

What these scientists are talking about is planets that are solid (not gas) and have some kind of atmosphere. The vast majority, if not all of them, are Earth-like only in the same sense that Mars and Venus are Earth-like - but entirely usuited to sustaining life.

Sun, 2009-02-15 15:22

500_Apples

M. Spector wrote:

This is old news.

We've been reading stories like this since the 1970's.

The term "Earth-like" is very vague and misleading. Any planet that is truly like ours would almost certainly, given enough time, evolve intelligent life.

What these scientists are talking about is planets that are solid (not gas) and have some kind of atmosphere. The vast majority, if not all of them, are Earth-like only in the same sense that Mars and Venus are Earth-like - but entirely usuited to sustaining life.

Your description is so narrow as to be incorrect.

The stuff you were reading in the 1970s was pure speculation, currently the field of exoplanet detection is evolving extremely rapidly as data comes in and constraints are imposed from real-world observations.

Sun, 2009-02-15 15:25

500_Apples

remind wrote:

The "wraith". ;)

And his view is very this earth centric, if not adhering to "Biblical" pronunciations, why would there be only "bacteria" on other planets.

Some might argue that assuming the Earth is "special" is more Earth-centric than assuming it is typical. For example in the Copernican revolution the Earth went from being the unique center to being just another of the six planets (known at the time).

Sun, 2009-02-15 15:25

M. Spector M. Spector's picture

News-flash: It's still speculation.

So what do you scientists mean by "Earth-like"?

Sun, 2009-02-15 15:27

#10

500_Apples

M. Spector wrote:

News-flash: It's still speculation.

So what do you scientists mean by "Earth-like"?

High density rock in the habitable zone of a star.

For example, Venus would be an Earth-like planet if it had formed further out.

Sun, 2009-02-15 15:35

#11

Unionist

Q: Why did the first chicken cross the road?

[size=8]Big prize for first correct answer.[/size]

Sun, 2009-02-15 15:39

#12

M. Spector M. Spector's picture

"Habitable zone" is a weasel expression that merely begs the question of life.

If it has life, it's in the habitable zone (by definition) and therefore "Earth-like". Conversely, if it resembles Earth to a great degree but has no life, it's outside the habitable zone (by definition) and therefore not "Earth-like".

The fact is, you can't define the "habitable zone" around a star in advance of finding life in it.

Sun, 2009-02-15 15:49

#13

500_Apples

M. Spector wrote:

"Habitable zone" is a weasel expression that merely begs the question of life.

If it has life, it's in the habitable zone (by definition) and therefore "Earth-like". Conversely, if it resembles Earth to a great degree but has no life, it's outside the habitable zone (by definition) and therefore not "Earth-like".

The fact is, you can't define the "habitable zone" around a star in advance of finding life in it.

Wow your tone is arrogant. M. Spector,

It is generally unwise to deliver conclusive verdicts when knows absolutely nothing about a subject. The fact you call habitable zone a weasel expression means you've either never looked it up or you simply don't know how to look up such things.

Additionally, habitable does not mean the same thing as inhabited. What you think habitable zone means is in fact what would be meant by the term "inhabited zone", which is not used as terminology for the reasons you associate with "habitable zone".

The paper I link to discusses some of the ideas of what a habitable zone is and what the necessary factors. No it isn't simple - it's called an "area of active research".
http://www.geosc.psu.edu/~kasting/PersonalPage/Pdf/Icarus_93.pdf

BTW, in general, saying that a term is complicated does not invalidate the use of a term. If science were that trivial it would not attract many scientists.

Sun, 2009-02-15 16:21

#14

M. Spector M. Spector's picture

Thanks for the link to the article.

As I suspected, scientists are not even in agreement on where the Habitable Zone is in our own solar system, and their definitions and arguments are based entirely on the results of actual observations of the planets in our solar system, only one of which is known to have life.

They are far from being able to decide where the habitable zone is in any other solar system, because that would require the same kind of knowledge about conditions out there as we have of conditions "in here".

Astronomers observing us from the third planet around Gliese 581 wouldn't have much of a clue as to where the HZ is in our system unless they happened to be able to determine there was life on Earth. If it were not for the fact that there is life on Earth, it would be entirely possible to argue that our solar system has no HZ, or has one somewhere other than where our orbit lies.

The quest to define habitable zones anywhere is based on our knowledge of only one example of life in the entire universe, which is too small a sample to make generalizations about.

Is Mars in the HZ? If we had discovered life on Mars, it would be. We didn't, so it isn't.

Sun, 2009-02-15 16:21

#15

Unionist

Contest is over - buncha losers...

Q: Why did the first chicken cross the road?

[i]A: To boldly go where no chicken had gone before.[/i]

Sun, 2009-02-15 17:14

#16

NorthReport

18 days till Kepler launch time.

Implications of Stellar Migration

http://www.iop.org/EJ/abstract/1538-4357/684/2/L79

Immigrant Sun: Our Star Could be Far from Where It Started in Milky Way

http://newswise.com/articles/view/544325/

Sun, 2009-02-15 17:22

#17

NorthReport

Maybe this space junk is causing our global warming.

http://photoblog.msnbc.msn.com/archive/2009/02/12/1792539.aspx?GT1=43001

Sun, 2009-02-15 17:23

#18

Fidel

Unionist wrote:
remind wrote:

... why would there be only "bacteria" on other planets.

Your viewpoint seems rather complex-lifeform-centric. What's wrong with being a bacterium? They've survived a lot longer than your species has.

Bacteria are sometimes observed crossing the floor of the House of Commons to becoming a slightly different genus of the same kingdom.

Found 20 lightyears away: the new Earth

Quote:

This remarkable discovery appears to confirm the suspicions of most astronomers that the universe is swarming with Earth-like worlds.

We don't yet know much about this planet, but scientists believe that it may be the best candidate so far for supporting extraterrestrial life.

The new planet, which orbits a small, red star called Gliese 581, is about one-and-a-half times the diameter of the Earth.

It probably has a substantial atmosphere and may be covered with large amounts of water - necessary for life to evolve - and, most importantly, temperatures are very similar to those on our world. . .

It may be some time before we detect any such signals, but it is just possible that today we are closer than ever to finding life in the stars.

William Hill said it had shortened the odds on proving the existence of extraterrestrial intelligence from 1,000-1 to 100-1.

Sun, 2009-02-15 17:41

#19

500_Apples

M. Spector wrote:

Thanks for the link to the article.

As I suspected, scientists are not even in agreement on where the Habitable Zone is in our own solar system, and their definitions and arguments are based entirely on the results of actual observations of the planets in our solar system, only one of which is known to have life.

They are far from being able to decide where the habitable zone is in any other solar system, because that would require the same kind of knowledge about conditions out there as we have of conditions "in here".

Astronomers observing us from the third planet around Gliese 581 wouldn't have much of a clue as to where the HZ is in our system unless they happened to be able to determine there was life on Earth. If it were not for the fact that there is life on Earth, it would be entirely possible to argue that our solar system has no HZ, or has one somewhere other than where our orbit lies.

The quest to define habitable zones anywhere is based on our knowledge of only one example of life in the entire universe, which is too small a sample to make generalizations about.

Is Mars in the HZ? If we had discovered life on Mars, it would be. We didn't, so it isn't.

You are so hopelessly arrogant.

It simply doesn't occur to you that your criticisms have occurred to other people before you and have been discussed and dealt with, it simply does not occur to you that the issues you perceive may be due to your lack of knowledge.

M. Spector wrote:
Astronomers observing us from the third planet around Gliese 581 wouldn't have much of a clue as to where the HZ is in our system unless they happened to be able to determine there was life on Earth.

Actually they would have a lot more than a clue. Had they been observing our star with the detail to which we've observed their star, they would know that our sun has a high metallicity with a lot of complex elements in high abundance, that it is a single star, and that it has two gas giants with a mass ratio of 1/1000 and then 2/5 at distances of ~5 and then 10 AUs. They would also know that this information is [i]not enough[/i] to fully explain the system, and that it would be a prime candidate to have a planet in the right spot and thus for life. Within 5 years they would be able to tell if there's an "Earth" there. Within 20 years they would be able to measure the chemistry of that "Earth".

If we found life on Mars it would very possibly be contamination from one of our probes. It could also be remnants from an earlier time when Mars was warmer, had oceans and was probably fertile ground for evolution. And we found that life was still there and vibrant - THEN YEAH NEW KNOWLEDGE WOULD HAVE TO BE INCORPORATED !!! If a theory could deal with ANY set of hypothetical explanations, which is the type of theory you seem to prefer, then in fact you have a theory of no value.

Sun, 2009-02-15 17:57

#20

Papal Bull

Yeah, I've noticed a major string of carbon chauvinism in this thread.

Sun, 2009-02-15 18:02

#21

500_Apples

Papal Bull wrote:
Yeah, I've noticed a major string of carbon chauvinism in this thread.

Carbon is one of the most abundant elements in the universe and has a very complex chemistry since it has 4 valence electrons. Dysprosium-based life is a low probability event due to the low quantity of dysprosium.

Sun, 2009-02-15 23:43

#22

Fidel

We are not alone: 'trillions' of planets could be supporting life

Quote:

Almost every star similar to the Sun probably has a life-harbouring planet like the Earth in orbit around it, a leading astronomer said yesterday.

The discovery of hundreds of planets around distant stars in our galaxy suggests that most solar systems have a world like ours that is capable of supporting life, and many of them are likely to have evolved it, according to Alan Boss, of the Carnegie Institution in Washington.

Nasa’s Kepler spacecraft, which will be launched next month to seek Earth-like worlds, is expected to find thousands of rocky planets in the patch of sky it surveys, Dr Boss told the American Association for the Advancement of Science conference in Chicago.

“We’re on the verge of finding out convincingly how frequently habitable planets occur in the Universe,” he said. “A little over 20 years ago we knew of no other planetary system other than our own. We now know of well over 300. . .

“About three or four years from now there’ll be a press conference announcing how frequently Earths occur. It’s quite an exciting time to be alive."

His expectation was that 85 per cent of Sun-like stars had one Earth-like planet, and that some could have many more. Given that there are 100 billion Sun-like stars in the galaxy, and 100 billion galaxies in the Universe, there may be 10 billion trillion planets that are good candidates for life. That is a one followed by 22 noughts.

Mon, 2009-02-16 14:12

#23

Lost in Bruce County

Something I have noticed over the years - many Trekkies lurk in the NDP. They are divided however, on whether Caption Picard or Caption Janway was the better caption...

Mon, 2009-02-16 16:00

#24

remind

500_Apples wrote:
Some might argue that assuming the Earth is "special" is more Earth-centric than assuming it is typical. For example in the Copernican revolution the Earth went from being the unique center to being just another of the six planets (known at the time).

Well, I do not think we are at cross purposes here at all, it is my perception that he was arguing that it is both "typical" and "special" at the same time.

Essentially stating that there were millions, if not billions of planets like earth out there, which could sustain, or are sustaining, life forms, BUT, they would only be of the bacterial type, and as such are not as "evolved" as earth is.

Mon, 2009-02-16 22:13

#25

Fidel

Michio Kaku on aunts, hyperspace, inflationary bubbles, and ET youtube

Wed, 2009-02-18 03:41

#26

Doug

Lost in Bruce County wrote:

Something I have noticed over the years - many Trekkies lurk in the NDP. They are divided however, on whether Caption Picard or Caption Janway was the better caption...

How is this even a question? Picard, of course.

Thu, 2009-02-19 00:08

#27

Lost in Bruce County

Captain Janeway all the way!

Thu, 2009-02-26 21:16

#28

Papal Bull

Pft, the NDP doesn't know what's what.

Sisko is the winner.

Sat, 2009-03-07 20:29

#29

Fidel

Theoretical physicist-comedian Michio Kaku says that going boldly where no man has gone before is not a very efficient way of exploring the universe. He says a more likely encounter with a type III civilization would be with von Neumann probes, or similar to the monolith in Arthur Clarke's [url=http://en.wikipedia.org/wiki/2001_Book#Plot_summary][color=mediumblue]2001: A Space Odyssey[/color][/url] Kaku says that man's transition to type I obviously didnt occur by 2001 but is still the most important phase of human development as well as the most dangerous and will occur more realistically by 2101. I dont fully agree with Kaku though that terrorists are the only people who fear democratization and advanced technology. I think Albert Einstein said it well when he wrote that we must evolve beyond this current phase of predatory capitalism. I also think progress is still retarded by periodic regressions into state sponsored imperialism and barbarism.

[url=http://vids.myspace.com/index.cfm?fuseaction=vids.individual&videoID=641... to video[/color][/url]

Fri, 2009-03-13 23:20

#30

NorthReport

Wow, a new religion!

We are probably not alone.

http://www.koreatimes.co.kr/www/news/opinon/2009/03/137_41254.html

Quote:
Is intelligence a rare accident in the evolutionary process, or such a self-destructive attribute that intelligent species don't usually survive more than a couple of centuries after they industrialize? Are they all observing radio silence because there is something dreadful out there? Or have we just not figured out yet how mature galactic civilizations communicate?

Sat, 2009-03-14 00:15

#31

Fidel

NorthReport] Wow, a new religion! <img src="/sites/all/modules/tinymce/tinymce/jscripts/tiny_mce/plugins/emotions/images/smiley-laughing.gif" border="0" alt="Laughing" title="Laughing" /> We are probably not alone. <a href="http://www.koreatimes.co.kr/www/news/opinon/2009/03/137_41254.html">http://www.koreatimes.co.kr/www/news/opinon/2009/03/137_41254.html</a> [quote=Gwynne Dyer wrote:
Are they all observing radio silence because there is something dreadful out there? Or have we just not figured out yet how mature galactic civilizations communicate?

[url=http://www.eskimo.com/~nanook/et/2008/10/michio-kaku-on-alien-secrecy.ht... Kaku on alien secrecy[/color][/url]:

Quote:
To recant; SETI first listens to very narrow band channels, thus it is unable to detect modulation or sidebands, it is only capable of detecting carriers. Most of our modern communications is moving away from simple modulated carriers into modulation schemes that spread the information out across a very broad bandwidth because these schemes make the most efficient use of bandwidth, power, and are most immune to interference.

SETI would not be able to receive any information transmitted and with our most modern communications it wouldn't register anything at all except perhaps a slight rise in background noise.

But in addition to that problem, even with huge amounts of power, with the distances involved, a signal could only be received with very high gain (dish) antennas pointed directly at each other. . .(lists SETI protocol)

The ONLY way that SETI will detect an alien signal is if they crash a saucer into the building or aliens are intentionally beaming a signal specifically at us and keep re-aligning their antenna to track the movement of Earth relative to their position.

Given all of these variables, I don't think SETI is ever likely to detect anything making what they do after detection entirely moot.

That said; SETI has detected some signals that appear to be extraterrestrial and not possessing characteristics of any known natural objects, but none of them were observable the next day thus none passed SETI protocol requirements.

And it sounds like even MK is for maintaining radio silence. Is it better to speak or to listen?

"Who knows what has come from the galaxy? Who knows what lurks in the sky? Beyond God. Watch those around you. For who knows what today, tonight, or tomorrow will bring." -- VO narration from John Carpenter's, "The Thing"

Sat, 2009-03-14 01:54

#32

martin dufresne

How dare we presume that we are any experts on intelligent life, when all signs predict this planet will cease to be a habitable zone within decades, a few centuries at best, because of our very own negligence - regardless of Michio Kaku "War of Civilizations" rehash?

(I hear the cockroaches laughing.)

Sat, 2009-03-14 03:35

#33

Fidel

Kaku says SETI's limted search for intelligent signals at or near the frequency of hydrogen amounts to a person who's lost a key and decides to look for it beside a lamp post at night. But when asked why theyre looking next to a lamp post, the person says, Well that's where the light is. But this is absurd, because the person is neglecting to consider that the lost key may be farther away from the lamp post and in the dark.

Sat, 2009-03-14 13:15

#34

Tommy_Paine

Well, there's such a lack of data right now this is just a fun excersize in speculation-- not that there's anything wrong with that.

I'm reminded of the first solar systems we observed. Gas giants in close orbits around their suns--exactly where our solar system's example, and simple logic would indicate they shouldn't be. Indicating that we are either a very unusual solar system, or that our methods for observing other solar systems only gave us odd results. I tend to think it was the latter.

As our methodology improves, we will get a clearer picture. Any observations from the Kepler telescope are three years from release.

I doubt I will live long enough to see it, but perhaps some of us here will see the day when telescopes will be sensitive enough to read the spectroscopy of planets orbiting where liqiud water might be possible.

That would be interesting.

Sat, 2009-03-14 15:53

#35

Fidel

One might wonder how people living in just the 17th century would have been astounded by even our technological advances just a few hundred years into the future. How would people living in horse and buggy days have understood today's high speed trains and gas powered buses, computers, and what Kaku describes as a type one civilization telephone system, the internet?

And what of these sightings in the sky and photographed by people with the first cameras, and even depicted in medieval paintings? Were they viewing von Neumann probes from another world centuries ago? Were they witnesses to a Stanley Kubrick type monolith in the sky that's been waiting to report back to ET the date and time humans attain type one civilization status? Or as Kaku says, an alien monolith could be there on the moon for centuries as small as a bread box, and we havent discovered it yet.

Sat, 2009-03-14 20:24

#36

Tommy_Paine

I think the painting of, then later the photography of atmospheric phenomena means that these phenomena have been with us for a while.

I was always curious as to how my grandparent's generation should have been in constant awe, being born before the Wright brothers took to the air, and living to see the moon landing. But, people of that generation seemed to take it all in stride.

And, so do we. Once we get marvelous new toys to play with, and become reasonably adept at using them, it seems as if we had them all along.

Look at something as revolutionary as Guttenberg's printing press. It seems like it was something that should have been invented shortly after the invention of writting itself, instead of, what, two millenia later.

Sun, 2009-03-15 15:51

#37

NorthReport

They are obviously very friendly!

Sun, 2009-03-15 15:54

#38

Fidel

Tommy_Paine wrote:

I think the painting of, then later the photography of atmospheric phenomena means that these phenomena have been with us for a while.

Sorry for focussing on this first comment. But for a long time, skeptics have said there is no evidence of UFO's. But there is beginning with old paintings and written accounts. And today there are photographs, eye witness accounts from ordinary people on up to US presidents and international goverenments release of records. There exists physical radar evidence of the 'phenomenon' from various countries.

physicist believes that UFOs are real!(And that they have visited us!)

pilots and baggage handlers at O'Hare report seeing 'phenomona' (youtube)

Why is a certain government afraid to admit that they just dont know? Why do they offer explanations that are sometimes more outlandish and prone to conspiracy theory than the people reporting what theyve seen with their own eyes? I suppose "we dont know" would tend to weaken the world image of a global superpower and its world police force.

Sun, 2009-08-09 04:25

#39

Fidel

[url=http://www.thetechherald.com/article.php/200932/4209/BBC-captures-amazin... captures weather balloon/swamp gas on video[/url]

[url=http://www.allnewsweb.com/page7977979.php]Teachers in Argentina photograph swamp gas/planet venus hovering off the ground[/url]

Sun, 2009-08-09 04:57

#40

Pogo

Is evolution to intelligent (ability to build an electron microscope) life a necessary step. Dinosaurs did just fine with tiny brains and mammals only came when the evironment was severely stressed.

Sun, 2009-08-09 05:34

#41

Fidel

Quote:
"...it's only on the brink that people find the will to change. Only at the precipice do we evolve." - Professor Barnhardt, The Day the Earth Stood Still (sci-fi)

Sun, 2009-08-09 08:57

#42

marzo

There are theories that life could exist on a water-bearing world even if it is too far from a star and too cold for an Earth-like environment. Europa, a moon of Jupiter is thought to have a thick layer of frozen water beneath which could be a living ecosystem. The distance from the Sun would not be a problem if there is geothermal heat.

Although this is science fiction, Arthur C. Clarke referred to this in the sequels to "2001:A Space Odyssey", "2010 : Odyssey Two" and "3001: The Final Odyssey".

Sun, 2009-08-09 09:18

#43

marzo

If there is extraterrestrial life its forms would be a result of the environment, obviously. For instance, if there were intelligent life forms capable of tool-making and complex language that lived in an aquatic environment they would not be able to create or control fire, but they could use electricity.

What would intelligent life be like if they were hermaphrodites, or if they laid eggs, or had reproductive functions completely different from what we know?

Perhaps life may not be limited to habitable zones as we understand them if geothermal heat and nutrients take the place of photosynthesis as it is on Earth.

Sun, 2009-08-09 09:56

#44

Spectrum

Hubble Finds Extrasolar Planets Far Across Galaxy

Quote:
Image: This top image is of one-half of the Hubble Space Telescope field of view in the Sagittarius Window Eclipsing Extrasolar Planet Search (SWEEPS). The green circles identify 9 stars that are orbited by planets with periods of a few days. The bottom frame identifies one of two stars in the field where astronomers were able to spectroscopically measure the star’s back-and-forth wobble due to the pull of the planet. Credit: NASA, ESA, K. Sahu (STScI) and the SWEEPS science team

See:Hubble Finds Extrasolar Planets Far Across Galaxy

Quote:
The Hubble SWEEPS program is an important proof-of-concept for NASA's future Kepler Mission, scheduled for launch in 2008. The Kepler observatory will continuously monitor a region of the Milky Way galaxy to detect transiting planets around mostly distant stars. Kepler will be sensitive enough to detect possibly hundreds of Earth-size planet candidates in or near the habitable zone, the distance from a star where liquid water could feasibly exist on a planet's surface.

Interesting, despite differences of opinion as to it's validity.

PS.(Just a point of interest when quoting, somtimes added html contributes to the small wording to follow. Look at post under html icon and you will discover what I am saying. Just remove the unnecessary html and repost and things should appear properly again.)

Sun, 2009-08-09 12:43

#45

Kaspar Hauser

What's out there? A bullet with our bloody name on it, that's what's out there:

http://solar-system-astronomy.suite101.com/article.cfm/jupiter_hit_by_comet_or_asteroid
"The infrared images gathered on Monday, July 20, 2009, show an impact point near the south polar region of Jupiter. The dark scar where the object impacted is next to bright upwelling particles in the upper atmosphere detected in near-infrared wavelengths. The upper troposphere shows warming with possible extra emission from ammonia gas. In infrared the impact point is bright, while in visible light the impact appears dark against the atmosphere. The scar is approximately the size of the Pacific Ocean."

Sun, 2009-08-09 13:06

#46

Tommy_Paine

What's out there?

Mostly space, hence the name.

With our current equipment, I'm afraid all we'll see is enough to spawn nasty speculative arguments on message boards.

I hope I live long enough to see the use of equipment that will enable spectograhy of light reflected off these rocky planets we're finding now.

That will probably give us a good enough data to... have lots more nasty speculative arguments on message boards.....

Space. It just goes on and on......

Sun, 2009-08-09 14:03

#47

marzo

Michael Nenonen wrote: "What's out there? A bullet with our bloody name on it..."

I don't have a link for this but my understanding is that the presence of 4 gas giants in our star system enables Earth to be a life-bearing world by presenting large targets for asteroids. Most large objects are pulled by the powerful gravity of the gas giants, sparing Earth from most catastrophic collisions.

Sun, 2009-08-09 14:46

#48

Fidel

[url=http://www.youtube.com/watch?v=Kw8dcb8iKSM]Theoretical physicist Michio Kaku on SETI and other life in outer space(besides ourselves obviously)[/url] (YouTube)

Kaku says that SETI probably will not discover alien communication signals in the next 100 years. He says theyve scanned a narrow range of radio frequencies which amount to searching a small neighborhood in our own galaxy. SETI is scanning frequencies near the frequency of Hydrogen, which is absurd says Kaku.

Sun, 2009-08-09 15:14

#49

Kaspar Hauser

Marzo: Yeah, I comforted myself with that idea too, but some recent computer simulations suggest that Jupiter's gravity redirects the orbits of many asteroids and comets towards the interior of the solar system, compensating for the number that it sucks into itself: http://arxiv.org/abs/0806.2795

If so, then Jupiter...and likely the other gas giants...don't have any net effect on the number of threatening near-Earth objects.

Sun, 2009-08-09 16:48

#50

marzo

Maybe I should wear a hard hat to guard against falling asteroids.

Sun, 2009-08-09 22:12

#51

Fidel

[url=http://www.youtube.com/watch?v=vXqbi3kaYxg&feature=channel]WIll We Ever Be a Galactic Civilization?[/url] YouTube

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