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Astronomers Estimate Milky Way May Have 100 Billion Alien Worlds
astroengine writes "Last year, using the exoplanets discovered by the Kepler space telescope as a guide, astronomers took a statistical stab at estimating the number of exoplanets that exist in our galaxy. They came up with at least 50 billion alien worlds. Today, astronomers from the Space Telescope Science Institute (STScI) in Baltimore, Md., and the PLANET (Probing Lensing Anomalies NETwork) collaboration have taken their own stab at the 'galactic exo-planetary estimate' and think there are at least 100 billion worlds knocking around the Milky Way."
Then statistically tell me which planet has Amazonian Women, hot green chicks, and Galactic Girls Gone Wild.
No tentacle monsters though, they will take all our womens!
aren't all worlds, not our own, alien?
Why couldn't I be born to a universe with a less restrictive set of physical laws?!
100 Billion is likely too low. Based on a survey of close suns using Doppler shift indicated at least 50% had planetary systems of some sort. I think the future will boost this percentage to 90% or better, probably virtually all suns have some kind of orbiting object that could be termed a planet. Depending on where you draw the line on size this makes for probably more than 2 Trillion alien worlds in the Milky Way alone (which is estimated to have 200-400 billion suns).
As for examining Kepler Objects of Interest (KOIs) more closely it seems there is little point to single them out. So what if we know they have planets -- everywhere you could point a radio dish there are planets. I am a big supporter of SETI and this is all good news for SETI, but it doesn't do anything to narrow the search.
Letter To Iran
Alien life in the universe that we could encounter, depending on the climactic conditions, gravity and atmosphere would be very different from humans to say the least. They would not be all humanoid races that speak english and can walk and act just like humans, they might be boneless creatures like an octopus or evolved dolphins that pilot ships full of water, or something that we have not even encountered yet. Dolphins show amazing intelligence so it is easy to imagine, that if they evolved over the course of millions of years on a remote planet and developed mathematics and science, they could invent space flight. Star Trek had humanoid aliens as standard, but the science fiction of Larry Niven envisaged quite different creatures such as the puppeteers.
Not to forget the even stranger aliens in the book Sundiver by David Brin. Discovery channel one time showed a Jupiter sized Earth like planet that had small creatures crawling along its surface that had to eat continually in order to have enough energy to move in the massive gravity. I am not sure if it is possible for such a large planet to form, most large planets that have been discovered are gas giants. But any alien planet we visited could have alien bacteria that we would not have a immunity to and it could be very dangerous if we brought it back to Earth. So any future space exploration would still require caution.
liberare massarum ex ignorantia, clausa descendit molestie.
50 billion here, 100 billion there. Pretty soon you're talking big numbers.
Now this is an interesting number, for by a curious coincidence there are approximately a hundred billion stars in our local universe, the Milky Way. So for every man who has ever lived, in this Universe there shines a star.
But every one of those stars is a sun, often far more brilliant and glorious than the small, nearby star we call the Sun. And many--perhaps most--of those alien suns have planets circling them. So almost certainly there is enough land in the sky to give every member of the human species, back to the first ape-man, his own private, world-sized heaven--or hell.
How many of those potential heavens and hells are now inhabited, and by what manner of creatures, we have no way of guessing; the very nearest is a million times farther away than Mars or Venus, those still remote goals of the next generation. But the barriers of distance are crumbling; one day we shall meet our equals, or our masters, among the stars. "
"The greatest lesson in life is to know that even fools are right sometimes" - Winston Churchill
Alien life in the universe that we could encounter, depending on the climactic conditions, gravity and atmosphere would be very different from humans to say the least. They would not be all humanoid races that speak english and can walk and act just like humans, they might be boneless creatures like an octopus or evolved dolphins that pilot ships full of water, or [...].
Ships full of water - multiply the difficulties to escape the gravity well by about 1000.
Imagine developing metallurgy and special ceramics (I reckon these would be needed for at least propulsion) in/under water...
Questions raise, answers kill. Raise questions to stay alive.
In a couple years kepler will have sufficient data so we can estimate the number of rocky worlds in habitable zones, that's what is most interesting to me. Once we find such worlds, we'd need to fund the type of probe that can analyze atmosphere, life as we know it does a very detectable transformation. Then step up our optical SETI efforts in those world's directions (they won't use radio waves, sorry microwave SETI dudes....)
I'm not sure why you want to shout Fermi Paradox, it is not an answer but a question.
20 years or more ago we could have speculated that planetary systems were rare, thus life had few places to evolve on and that could have been a possible solution to the Fermi Paradox -- finding so many worlds deepens the Fermi Paradox.
Let us hope Fred Saberhagen doesn't have the correct answer to the question with his Berserker series of novels.
Letter To Iran
Alien life in the universe that we could encounter, depending on the climactic conditions, gravity and atmosphere would be very different from humans to say the least.
Not proven until we meet one.
They would not be all humanoid races that speak english....
Star Trek did not portray this.
Dolphins show amazing intelligence so it is easy to imagine..
No, it is not easy to imagine. Dolphins lack the dexterity to build a space ship. We may find out that any given species rarely (if ever) reach space unless they meet certain other criteria like opposable thumbs and originate from a planet where it's easy to start a fire. We don't know what all is involved in inspiring a species to leave the planet, just that it likely requires a complex series of events.
It's easy to jump to the conclusion that every planet that sports life will create a random space faring civilization species. However, to put things into a more realistic perspective, consider that this planet has created over a hundred million species of life and only one has intentionally gone into orbit.
Star Trek had humanoid aliens as standard...
No, they did not. The 'humanoid' races were explained by one species that seeded our area of the galaxy with similar genetic material. Elsewhere in the series, the Federation was accused of really only allowing humanoids to join.
We just don't know.
"I like to lick butts!" by MobileTatsu-NJG (#32700246) (Score:5, Informative)
So you went out on your first date, don't be so dramatic.
we could be awash in ETI signals and not know it yet. there is no reason to even think we have a Fermi Paradox, we're too new at long distance communication.
Or even some clever use of entangled particle pairs. (Simply because we haven't figured out how to use them for comm doesn't mean others haven't.)
Personally though, I think seti is looking for the wrong things.
Instead of trying to eavesdrop on the grey aliens ordering space pizza from planet foodcourtia, they should be looking for localized light displacements from known stellar markers, as caused by the huge gravitational eddies that several hypotherical FTL systems would make. Interstellar highways would show up on a sufficiently detailed map of the CBR because of the regular disruptions.
(This assumes something like an albucare (however you spell his name...) warp drive though, which create a wave of negative spacial curvature behind the vessel, and a synthetic gravity well in front.)
Our current CBR maps are pretty coarse, since we are dealing with single measurement devices with very wide frequency emmisions, so a highway search would require interferometry to be fruitful. We need to launch about 50 more COBE sats up.
Disney sued them for copyright infringement. That's why they had to stop calling Pluto a planet.
I think the issue is how does this water creature develop fire and metal smelting in the first place (you know bronze and iron age level) - once they have technology working around it is easy, the tricky bit would be developing that technology in the first place.
You can create fire underwater, it's a different chemical process to on land.
Besides, you dont need fire for smelting, you simply need heat and there are plenty of active underwater volcano's on earth as well as other heat sources.
Needless to say, an aquatic civilisation would develop things in radically different ways to the way we have.
Calling someone a "hater" only means you can not rationally rebut their argument.
It doesn't matter, you lose, by a long shot.
(Which you learn when you read the details and learn that this only applies to worlds about 5x as big as earth. Everything smaller is left out of the estimate, and may result in the final number being as much as 5-10x higher).
"Who is the Journal of Quantum Physics going to believe?" --Stephen Hawking
Since when has prior use stopped them from suing someone?
You do realize that only the humans in Star Trek spoke English, right? Everyone used universal translators to reduce communications problems. They just didn't portray it the way some other sci-fi has; for instance, in the movie Dune, in the first scene, when the Guild Navigator meets with the Emperor, his helpers speak first using a mechanical device that translates their language, and you can hear both. Star Trek just eliminates that for budget reasons and to avoid distracting viewers.
Besides, 300+ years in the future it's quite possible we won't be speaking English at all, or it might be very different from what we speak now. With any sci-fi that's in English and set in the future, you might as well assume that all the dialog has been translated into modern English for the benefit of the reader. I believe the Dune series (set 10,000 years in the future) even explicitly says they use a different language, or several in fact, but the characters' dialog is still in modern English so that the author didn't have to invent a new language like Tolkein's Sindarin.
But with alien slave girls, amazons, and the like, wouldn't it be more aptly named "planet 'boobs'" instead?
Amazons? Then that would be planet "Boob".
Well, 640 billion should be enough for anybody...
Excuse me, but please get off my Pennisetum Clandestinum, eh!
Because it isn't. They've done some very careful estimating here. This works off a combination of modelig and empirical data. We know how many stars Kepler has looked at and what approximate fraction of the total set of stars in the galaxy that represents. For those stars, we have a pretty good idea of lower bounds of how many planets they have, and we know what sorts of planets are the sort that Kepler would have trouble detecting. We can look at that distribution and use it to get a rough estimate. No one is claiming that this number is precise. But the true number is likely not more than an order of magnitude or two off. This isn't an asspull. This is scientists working very carefully very difficult stuff on the cutting edge and doing their best with hard work and rigorous thinking to produce an estimate. This is what real science looks like.
And I would say that I happen to know for a fact, that there are at least 8.