Atlantis Online
October 16, 2019, 12:36:26 am
Welcome, Guest. Please login or register.

Login with username, password and session length
News: Update About Cuba Underwater Megalithic Research
http://www.timstouse.com/EarthHistory/Atlantis/bimini.htm
 
  Home Help Arcade Gallery Links Staff List Calendar Login Register  

Have aliens become EXTINCT? Experts claim that even if extraterrestrial life for

Pages: [1]   Go Down
  Print  
Author Topic: Have aliens become EXTINCT? Experts claim that even if extraterrestrial life for  (Read 66 times)
Shiloh
Hero Member
*****
Posts: 471



« on: February 21, 2016, 08:33:18 pm »

Have aliens become EXTINCT? Experts claim that even if extraterrestrial life formed on other planets, it would have already died

    Scientists argue that life plays a key role in making planets habitable
    Unless it quickly evolves, life is unable to stabilise its planet's climate
    Life may have emerged in many worlds but then quickly became extinct

By Richard Gray for MailOnline

Published: 12:13 EST, 21 January 2016 | Updated: 16:27 EST, 21 January 2016



Astronomers have spent decades scouring the heavens for signals from aliens on other planets, but to no avail.

Rather than being too far away, or too technologically advanced for us to spot, however, researchers now believe there is a much simpler reason our efforts have been met with deafening silence - ET is already extinct.

A group of astrobiologists has claimed that life on other planets, if it managed to get going at all, would likely be brief and would die out quickly.

Scroll down for video
Astronomers have been peering at the sky for clues (Parkes radio telescope pictured) that there may be alien life forms on other planets for decades, but a new theory suggests that in the majority of cases, life would have died out quickly after appearing on a planet as it was not able to alter the climate of its world enough to survive

Astronomers have been peering at the sky for clues (Parkes radio telescope pictured) that there may be alien life forms on other planets for decades, but a new theory suggests that in the majority of cases, life would have died out quickly after appearing on a planet as it was not able to alter the climate of its world enough to survive

And they said that while many planets could have potentially been habitable, and may have once teemed with microbial life, runaway heating or cooling would have left their surfaces inhospitable.

In their new theory, the researchers looked at the role life can play in helping to control the climate of a planet, making it more habitable in the process.
RELATED ARTICLES

    Previous
    1
    2
    Next

    The (wobbly) march of the penguins: Video of the birds on...
    Did the universe undergo TWO Big Bangs? Physicists claim a...
    Is this mankind's first massacre? Prehistoric tribe of men,...
    Why Stephen Hawking is wrong about aliens being hostile:...
    Has the mystery of the 'alien Wow! signal' been solved?...

Share this article
Share
1k shares

They argue that while both Mars and Venus may once have been planets that could have hosted life four billion years ago, any life there failed to stabilise the environment.
ALIENS: FRIENDS OR FOE

If there are any intelligent alien life forms out there, Stephen Hawking thinks we're playing a dangerous game by trying to contact them.

The physicist believes that if aliens discovered Earth, they are likely to want to conquer and colonise our planet.

'If aliens visit us, the outcome could be much like when Columbus landed in America, which didn't turn out well for the Native Americans,' he said in a recent interview.

But co-founder and former director of the Seti Institute, Jill Tarter, doesn't think this will be the case.

She argues that any aliens who have managed to travel across the universe will be sophisticated enough to be friendly and peaceful.

'The idea of a civilisation which has managed to survive far longer than we have...and the fact that that technology remains an aggressive one, to me, doesn't make sense,' she said.

This resulted in Mars becoming a frigid desert while Venus became a boiling hothouse.

The researchers, based at the Australian National University, argue that life may well have emerged multiple times on other planets following the heavy bombardment of wet rocky worlds by asteroids.

But they said almost all of this life would go rapidly go extinct unless it was able to evolve fast enough to regulate greenhouse gases and so maintain stable surface temperatures.

Dr Aditya Chopra, the lead author of the paper and an astrobiologist at the Australian National University, said: 'The universe is probably filled with habitable planets, so many scientists think it should be teeming with aliens.

'Early life is fragile, so we believe it rarely evolves quickly enough to survive.

'Most early planetary environments are unstable.

'To produce a habitable planet, life forms need to regulate greenhouse gases such as water and carbon dioxide to keep surface temperatures stable.'

Dr Chopra and his colleagues, whose work is published in the journal Astrobiology, said life in the universe may depend on something they call the Gaian bottleneck.

This is where life plays a key role in modifying and regulating its environment to ensure its survival.

Earth provides a classic example of this as early organisms began regulating the amount of carbon dioxide in the atmosphere and eventually produced enough oxygen for other new organisms to emerge.
Life on most planets would not have had a chance to evolve beyond being microbes before dying out under the new theory. If true, it will dash hopes that we will one day meet complex and intelligent life forms (illustrated)

Life on most planets would not have had a chance to evolve beyond being microbes before dying out under the new theory. If true, it will dash hopes that we will one day meet complex and intelligent life forms (illustrated)
The surface of Mars (pictured) may once have teemed with microbial life four billion years ago, but it failed to stabilise the planet's climate causing the red planet to become a frigid world. This would have ultimately caused life on the planet to die out before it got going properly, the scientists said

The surface of Mars (pictured) may once have teemed with microbial life four billion years ago, but it failed to stabilise the planet's climate causing the red planet to become a frigid world. This would have ultimately caused life on the planet to die out before it got going properly, the scientists said

Unfortunately for those of us hoping to meet an alien life form, the Gaian bottleneck results in near universal extinction of life on other planets.

That said, recent discoveries with telescopes such as the Kepler Space Telescope have revealed that rocky Earth-like worlds are perhaps far more common than had been previously believed.

Indeed, a growing number of planets are being discovered in the so-called 'habitable' zone around their stars the area where liquid water could be expected to exist.

Even the basic ingredients for life hydrogen, oxygen, carbon, sulphur and phosphorus - are also thought to be abundant.

Yet despite the efforts of astronomers, like those involved in the Search for Extraterrestrial Intelligence, no signs of any life has been seen coming from these planets.

Our failure to find definitive signs of life even on our planetary neighbours may therefore be explained by this theory.
Telescopes such as Nasa's Kepler space telescope are revealing a growing number of rocky Earth-like planets that exist in the habitable zone around their stars. Some have even been found around stars similar to our own sun. But the theory suggests that if life did exist on any of these, it has probably already died out

Telescopes such as Nasa's Kepler space telescope are revealing a growing number of rocky Earth-like planets that exist in the habitable zone around their stars. Some have even been found around stars similar to our own sun. But the theory suggests that if life did exist on any of these, it has probably already died out

Dr Chopra continued: 'The mystery of why we haven't yet found signs of aliens may have less to do with the likelihood of the origin of life or intelligence and have more to do with the rarity of the rapid emergence of biological regulation of feedback cycles on planetary surfaces.'

Professor Charley Lineweaver, from the Planetary Science Institute at the Australian National University, who co-authored the paper, said Earth may be one of the rare places where life was able to gain enough of a foothold to ensure its own survival.

'Life on Earth probably played a leading role in stabilising the planet's climate,' he said.

He added that should we find evidence of bacteria having once lived on other planets, it will help to support their theory.

'One intriguing prediction of the Gaian Bottleneck model is that the vast majority of fossils in the universe will be from extinct microbial life, not from multicellular species such as dinosaurs or humanoids that take billions of years to evolve,' he concluded.

Read more: http://www.dailymail.co.uk/sciencetech/article-3410524/Have-aliens-EXTINCT-Experts-claim-extraterrestrial-life-formed-planets-died.html#ixzz40rO6a9EV
Follow us: @MailOnline on Twitter | DailyMail on Facebook
Report Spam   Logged

Shiloh
Hero Member
*****
Posts: 471



« Reply #1 on: February 21, 2016, 08:34:12 pm »

Report Spam   Logged
Shiloh
Hero Member
*****
Posts: 471



« Reply #2 on: February 21, 2016, 08:34:41 pm »




The surface of Mars (pictured) may once have teemed with microbial life four billion years ago, but it failed to stabilise the planet's climate causing the red planet to become a frigid world. This would have ultimately caused life on the planet to die out before it got going properly, the scientists said


Report Spam   Logged
Shiloh
Hero Member
*****
Posts: 471



« Reply #3 on: February 21, 2016, 08:35:01 pm »

Report Spam   Logged
Shiloh
Hero Member
*****
Posts: 471



« Reply #4 on: February 21, 2016, 08:35:28 pm »

Telescopes such as Nasa's Kepler space telescope are revealing a growing number of rocky Earth-like planets that exist in the habitable zone around their stars. Some have even been found around stars similar to our own sun. But the theory suggests that if life did exist on any of these, it has probably already died out

Report Spam   Logged
Shiloh
Hero Member
*****
Posts: 471



« Reply #5 on: February 21, 2016, 08:36:57 pm »

Even if we do find a habitable planet, could its indigenous life forms have already died out long ago ?
Astronomers at SETI have been listening out for signs of extraterrestrial civilizations for years but despite their best efforts have so far come up empty.

While many believe that the reason for this is that the distances between worlds is too great or that it is unlikely anyone within range would be at the same technological level as we are, astrobiologists at the Australian National University maintain that life on any nearby habitable worlds might have simply gone extinct long before we ever started looking.

"The universe is probably filled with habitable planets, so many scientists think it should be teeming with aliens," said study lead author Dr Aditya Chopra. "Early life is fragile, so we believe it rarely evolves quickly enough to survive. Most early planetary environments are unstable. "

The emergency of life on other worlds may be limited by what the scientists have called the 'Gaian bottleneck' which concerns the need for early organisms to modify and regulate the environment of a planet in order to ensure their own survival - something that did happen here on Earth.

"The mystery of why we haven't yet found signs of aliens may have less to do with the likelihood of the origin of life or intelligence and have more to do with the rarity of the rapid emergence of biological regulation of feedback cycles on planetary surfaces," said Dr Chopra.
Report Spam   Logged
Shiloh
Hero Member
*****
Posts: 471



« Reply #6 on: February 21, 2016, 08:38:01 pm »



The fragility of early life might make it particularly prone to extinction. Image Credit: NASA9 
Report Spam   Logged
Kristal Denn
Superhero Member
******
Posts: 1700



« Reply #7 on: February 21, 2016, 10:01:57 pm »

I believe, without evidence, that there is far, far more life out there, intelligent and otherwise than we likely imagine. With estimates upwards of 100 billion GALAXIES in our universe, the statistical chance of numerous "life elsewhere" is so high as to be a certainty, for me. I think some did indeed die-off. I also think that others thrived, evolved, advanced, etc.
Report Spam   Logged
Brooke
Administrator
Superhero Member
*****
Posts: 4269



« Reply #8 on: February 22, 2016, 01:15:30 am »

I have always liked the ant in the jungle theory. In a jungle there exists several millions of ants, consisting of hundreds of pounds of biomass, but the odds of any one individual ant ever seeing a Chinese or Dutch born native is very-very low. This does not mean that Chinese or Dutch people don't exist, it just means that they are most likely sticking close to home and not trashing around tropical jungles and making themselves visible to the ants. And keep in mind when people do take notice of ants it rarely ends well for them.
Report Spam   Logged

"The most incomprehensible thing about our universe is that it can be comprehended." - Albert Einstein
Pages: [1]   Go Up
  Print  
 
Jump to:  

Powered by EzPortal
Bookmark this site! | Upgrade This Forum
SMF For Free - Create your own Forum
Powered by SMF | SMF © 2016, Simple Machines
Privacy Policy