Most earth-like worlds have yet to be born, according to theoretical study

October 20, 2015 by Donna Weaver
This is an artist's impression of innumerable Earth-like planets that have yet to be born over the next trillion years in the evolving universe. Credit: NASA, ESA, and G. Bacon (STScI)

Earth came early to the party in the evolving universe. According to a new theoretical study, when our solar system was born 4.6 billion years ago only eight percent of the potentially habitable planets that will ever form in the universe existed. And, the party won't be over when the sun burns out in another 6 billion years. The bulk of those planets—92 percent—have yet to be born.

This conclusion is based on an assessment of data collected by NASA's Hubble Space Telescope and the prolific planet-hunting Kepler space observatory.

"Our main motivation was understanding the Earth's place in the context of the rest of the ," said study author Peter Behroozi of the Space Telescope Science Institute (STScI) in Baltimore, Maryland, "Compared to all the that will ever form in the universe, the Earth is actually quite early."

Looking far away and far back in time, Hubble has given astronomers a "family album" of galaxy observations that chronicle the universe's history as galaxies grew. The data show that the universe was making stars at a fast rate 10 billion years ago, but the fraction of the universe's hydrogen and helium gas that was involved was very low. Today, star birth is happening at a much slower rate than long ago, but there is so much leftover gas available that the universe will keep cooking up stars and planets for a very long time to come.

"There is enough remaining material [after the ] to produce even more planets in the future, in the Milky Way and beyond," added co-investigator Molly Peeples of STScI.

Kepler's planet survey indicates that Earth-sized planets in a star's , the perfect distance that could allow water to pool on the surface, are ubiquitous in our galaxy. Based on the survey, scientists predict that there should be 1 billion Earth-sized worlds in the Milky Way galaxy at present, a good portion of them presumed to be rocky. That estimate skyrockets when you include the other 100 billion galaxies in the observable universe.

This leaves plenty of opportunity for untold more Earth-sized planets in the habitable zone to arise in the future. The last star isn't expected to burn out until 100 trillion years from now. That's plenty of time for literally anything to happen on the planet landscape.

The researchers say that future Earths are more likely to appear inside giant galaxy clusters and also in dwarf galaxies, which have yet to use up all their gas for building stars and accompanying planetary systems. By contrast, our Milky Way galaxy has used up much more of the gas available for future star formation.

A big advantage to our civilization arising early in the evolution of the universe is our being able to use powerful telescopes like Hubble to trace our lineage from the big bang through the early evolution of galaxies. The observational evidence for the big bang and cosmic evolution, encoded in light and other electromagnetic radiation, will be all but erased away 1 trillion years from now due to the runaway expansion of space. Any far-future civilizations that might arise will be largely clueless as to how or if the universe began and evolved.

The results will appear in the October 20 Monthly Notices of the Royal Astronomical Society.

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AGreatWhopper
1.7 / 5 (6) Oct 20, 2015
Have yet to form. You can cut the cutesy kiddie come-ons and your knee jerk anthropomorphizing. School kids don't get assignments on this site anymore since you pimped the page out to anyone that wants to fund trolling.

If you want title come-ons for the current crop of trolls you're nurturing, you might try something like "Massive Black Hole Found to be Giving its Galaxy the Ultimate Blow Job".
SuperThunder
4 / 5 (7) Oct 20, 2015
Earth did it before it was cool.

Now we have to get into space so we can be that mysterious "progenitor" race that leaves weird alien artifacts and sentient logic traps all over the universe. Imagine aliens spending five hundred years trying to figure out "why is a mouse when it spins?"
yamancakiroglu
1 / 5 (5) Oct 20, 2015
Logic dictates that, according to this theoretical study, the first and only intelligent life forms are currently on the Earth. That is exactly what I have been thinking all along. Most importantly, it means that, as custodians of intelligent life in the universe, we must resolve all existing conflicts among ourselves, and create a sustainable future for next generations.
cjones1
1 / 5 (1) Oct 20, 2015
If the ancient Egyptians and other cultures heard right, the progenitor species came from Orion or Sirius. Of course, considering that we reached our current technological level over roughly 200 years after small steps in the previous 3000 years, humans could have reached the same or greater tech savvy several times over the last 20,000 years. Who knows what remnants are yet to be discovered or whether they have hidden or cloaked themselves in places we have yet to discover. Regardless, if humankind doesn't destroy itself or natural calamities don't take us out, we have many planets, star systems, galaxies, and a universe to explore!
javjav
4 / 5 (1) Oct 20, 2015
Any far-future civilizations that might arise will be largely clueless as to how or if the universe began
couldn't it be the opposite? Their Galaxy will still hold together by gravity (beyond that point no new stars can form from previous supernovaes, so no civiliation can appear anymore). Also they will still see clues like the last galaxies and stars fading out at fast (light waves are streteched, not "cut", also CBR) and they will see a much stronger redshift with the distance, so pretty much similar clues to what we have but more exagerated.
And specially, being "the last ones" they will have a good chance to get information collected or even broadcasted by previous civilizations.
Manfred Particleboard
not rated yet Oct 20, 2015
Cool....Lets get to one of these worlds, build some pyramids or some funky geometrically derived architecture and symbolically carve something representing the 1420MHz frequency.
(building everything with the fundamental unit of measure being 21cm) Sit back and watch the debates about it being built by Aliens.
Returners
2.3 / 5 (3) Oct 20, 2015
This leaves plenty of opportunity for untold more Earth-sized planets in the habitable zone to arise in the future. The last star isn't expected to burn out until 100 trillion years from now. That's plenty of time for literally anything to happen on the planet landscape.


1)You missed the fact that all extinct stars will eventually cool to a temperature where liquid water could exist on their surface, and they'd still be a reliable heat source, so that some form of life could survive right on the surface of a cooling star. However, the gravity would be quite the problem for anything larger than a prokaryote to deal with.

2) When the stars in a galaxy die out, radiation pressure from that galaxy decreases, potentially allowing more inter-galactic dust and gas to fall back into the galaxy. In this computer model, as you watch closely, see rogue dwarf galaxies and globulars form and fly by.

https://www.youtu...uwAtnKeg
Returners
2.3 / 5 (3) Oct 20, 2015
From 40 seconds to 1 minute in simulation, notice how much material is visible in the simulation, but is not part of any obvious galaxy or star-cluster...

As the main galaxy and the dwarfs cool, surely this material will eventually fall into them and re-start star formation...unless hubble expansion is faster than the attraction of gravity....
SkyLy
1 / 5 (3) Oct 20, 2015
Logic dictates that, according to this theoretical study, the first and only intelligent life forms are currently on the Earth. That is exactly what I have been thinking all along. Most importantly, it means that, as custodians of intelligent life in the universe, we must resolve all existing conflicts among ourselves, and create a sustainable future for next generations.


I'm sorry but the probability of what you say here is close to zero. To put it another way, "Since there are 1,000,000,000,000,000,000,000,000 planets, it is highly probable that what happened on Earth happened elsewhere".
We call this common sense.
Returners
2.3 / 5 (3) Oct 20, 2015
I'm sorry but the probability of what you say here is close to zero. To put it another way, "Since there are 1,000,000,000,000,000,000,000,000 planets, it is highly probable that what happened on Earth happened elsewhere".
We call this common sense.

Habitable planets, and your numbers are inflated.

I assumed 1.5 habitable planets per star, and 600 sextillian stars, and assumed the stars themselves would be habitable eventually in the long term, which gives me 1.5*10^21 habitable planets and stars.

There is no specific reason to believe life exists on a planet just because it is in principle capable of supporting life. There could be life on all those objects, or there could be life on none of them, or anything between.

I disproved the infinite monkey argument a long time ago, because although the monkey gets an infinite number of tries, there is only one correct answer, and there are actually greater than infinite wrong answers.
Returners
2.3 / 5 (3) Oct 20, 2015
There is actually infinite to the infinite power wrong answers.

So the probability of the monkey ever typing the complete works of Shakespeare is asymptotically close to Zero, even with an infinite number of tries.

Infinity is nothing compared to infinity to the power infinity..
yamancakiroglu
not rated yet Oct 20, 2015
To SkyLy:
I respect your view, however just read the article again:
"...4.6 billion years ago only 8 percent of the potentially habitable planets that will ever form in the universe existed. The bulk of those planets—92 percent—have yet to be born."
"...said study author Peter Behroozi...Compared to all the planets that will ever form in the universe, the Earth is actually quite early."
"...for untold more Earth-sized planets in the habitable zone to arise in the future. The last star isn't expected to burn out until 100 trillion years from now."
Therefore, it's highly probable that what happened on Earth "will" happen elsewhere.
That's called probability theory, and although it's still a theory and not a fact, in scientific matters it's better than common sense.
Edenlegaia
3 / 5 (1) Oct 20, 2015
I'm sorry but the probability of what you say here is close to zero. To put it another way, "Since there are 1,000,000,000,000,000,000,000,000 planets, it is highly probable that what happened on Earth happened elsewhere".
We call this common sense.


Close to zero does not mean zero. Highly probable does not mean certain. Well, you get my thoughts....
I tend to think, as well, that mankind may very well be the first sentient life form able to reach a cilivization of this level. Time will tell what's going on, but we shouldn't travel through space thinking "THERE ARE ALIENS!! E.T., i'm comiiiiiiiing!".
dan42day
4 / 5 (1) Oct 20, 2015
Well that might explain the Fermi Paradox...and also suggest that we stop playing with our collective navel, assuming someone already beat us to it, and start doing what life was meant to do, COMPETE!
my2cts
1 / 5 (1) Oct 21, 2015
Have yet to form. You can cut the cutesy kiddie come-ons and your knee jerk anthropomorphizing. School kids don't get assignments on this site anymore since you pimped the page out to anyone that wants to fund trolling.

If you want title come-ons for the current crop of trolls you're nurturing, you might try something like "Massive Black Hole Found to be Giving its Galaxy the Ultimate Blow Job".

I would say "Monster Black hole Lurking in the Dark Found etc ... just Like Einstein Predicted".
antialias_physorg
4.2 / 5 (5) Oct 21, 2015
Well that might explain the Fermi Paradox...and also suggest that we stop playing with our collective navel, assuming someone already beat us to it, and start doing what life was meant to do, COMPETE!

I dunno..with intelligence comes the ability to chose what we want life to be. Do we want to compete - i.e. go to war with every otherintelligence out there?
Or wouldn't we rather cooperate?
And even if we are the first (however unlikely that is) - then why should we not leave any other Earth alone. It seems far more interesting to me to see what develops in other places left to their own devices rather than plaster everything with a metaphorical McDonalds.
Egleton
5 / 5 (2) Oct 21, 2015
Can the ideology.
We are discussing astronomy.
dogbert
4.2 / 5 (5) Oct 21, 2015
When we speculate about earth like worlds, we are not really speculating about worlds formed in similar conditions to the earth when it formed, we are speculating about the existence of worlds containing life like the earth, because the earth we know is like it is because of the changes that life has made to the planet.

We can easily estimate probabilities of the existence of worlds formed in conditions like the early earth but we cannot estimate probabilities of earth like planets when we have found life only in this solar system.

There may be many earth like planets in this galaxy and there may be only one. We simply cannot estimate the probability with a single instance of a life bearing planet.
antialias_physorg
4.2 / 5 (5) Oct 21, 2015
Dear god...dogbert has made a cogent post. 5 stars from me.
bluehigh
1 / 5 (2) Oct 21, 2015
Or wouldn't we rather cooperate?


Cooperation - Among the many things Anti-Thinking knows nothing about.

Wipe your chin dribbling fool.
Hat1208
5 / 5 (4) Oct 21, 2015
@bluehigh

How could someone not know how to cooperate? And does cooperation really require previous knowledge of how to cooperate.
RealTorque
1 / 5 (2) Oct 21, 2015
This is absurd. I'm no astrophysicist, but there's a certain level of hubris involved in drawing conclusions about existing life in the "universe." We are making assumptions based on life as we know it, i.e., carbon based, which doesn't preclude the possibility of other life. And when we stop blowing each other up, then, maybe, we can start referring to ourselves as an "intelligent" species.
Uncle Ira
3.7 / 5 (6) Oct 21, 2015
I'm no astrophysicist, but there's a certain level of hubris involved in drawing conclusions about existing life in the "universe."


Not that I can understand why come up with the stuffs they come up with. But since they are the theoretical physicists isn't that what they are supposed to do? Take what they do know and see where it leads?

We are making assumptions based on life as we know it


If that is all they got to work with, it makes sense to me, but I am not a theoretical physics, I am not a scientist in anything.

which doesn't preclude the possibility of other life.


They spend a lot of time learning what they know and they probably have a reason for the pondering like they do.

And when we stop blowing each other up, then, maybe, we can start referring to ourselves as an "intelligent" species.


Skippy, I think you read the wrong article. This is not about what aliens are like. It is about the science of planets like earth forming.
bluehigh
3 / 5 (2) Oct 21, 2015
@Hat

Doubts persist about whether animals possess the cognitive abilities to sustain contingent cooperation.
Vietvet
5 / 5 (3) Oct 21, 2015
@Hat

Doubts persist about whether animals possess the cognitive abilities to sustain contingent cooperation.


"In sum, several factors may interact to motivate contingent cooperation in animals under natural conditions: the strength of the partners' social relationship, the nature of their recent interactions, and the opportunity to reengage in some form of cooperative behavior. Animals appear to possess many of the cognitive abilities thought to be essential for the emergence of contingent cooperation, if in rudimentary form."
http://www.ncbi.n...3131815/
bluehigh
5 / 5 (1) Oct 21, 2015
Ok, I will rephrase.

Cooperation - among the many things that Anti-Thinking knows very LITTLE about.
(Rudimentary)

"Doubts persist about whether animals possess the cognitive abilities to sustain contingent cooperation. These include the ability to remember specific interactions, to delay reward, to track favors given and returned, to plan and anticipate future outcomes, and to distinguish between cooperators and defectors".

- http://www.pnas.o...full.pdf

Edenlegaia
3 / 5 (2) Oct 22, 2015
Ok, I will rephrase.

Cooperation - among the many things that Anti-Thinking knows very LITTLE about.
(Rudimentary)

"Doubts persist about whether animals possess the cognitive abilities to sustain contingent cooperation. These include the ability to remember specific interactions, to delay reward, to track favors given and returned, to plan and anticipate future outcomes, and to distinguish between cooperators and defectors".

- http://www.pnas.o...full.pdf



We made it this far WITH/WITHOUT cooperation. Pick the one pleasing you the most.
Why wouldn't we go even further? You don't want to?
vidyunmaya
1 / 5 (1) Oct 24, 2015
Most Earth-like worlds have yet to be born, says new NASA study October 20, 2015
Necessity: Vision Development spiri: Save Earth planet -life Support
The Indian Philosophy forms the backbone for Biological minds to catch-up with the Galactic Plane . The Human Being has various frames of Minds
1.Biological Frame leading to 2.Philosophical Frame and superimposition of 3.Divine Frame. several questions arise out of 4.Nature Divine Frame and 5.Cosmic Divine Frame.
Here Super-imposition of visible-invisible matrix modes presented by the author at COSPAR 2013 helps scientific research to catch-up with Space data provided by NASA,ESA,HST many Space probes like SOHO in search of life and extra-terrestrial life. my books are available through lulu- Cosmology Vedas Interlinks-http://www.lulu.c...039.html
Vidyardhi nanduri {independent Research]
mk860
not rated yet Oct 25, 2015
The issue to me is not how many other worlds have or will have 'advanced' life. I don't think that matters so much. Of the estimated 4 billion species to have ever lived on this planet, just one has developed science, advanced tools, mathematics, society, language, etc. No matter how many Earth-like planets exist, and no matter how many of those develop life, the chance that life LIKE US exists elsewhere, now or in the future, is unlikely. We are searching for 'us' as that is all we can do since we can't even comprehend with other advanced life might be like. So at the end of the day, we may well be effectively alone, and in all likelihood will never communicate with any other form of life in our galaxy.
elaisakasan
1 / 5 (1) Oct 25, 2015
Dr. Steven Greer, Director of The Disclosure Project, and SIRIUS Disclosure, shows how Close Encounters of the 5th kind can be achieved by ordinary people through training and education. Give it a try. You may learn more than you ever dreamed.

M. T. Keshe is also teaching us a lot about the universe.

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