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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!
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
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
I think he's trying to say that its not necessary to say alien worlds, just say worlds. He does kinda have a point, saying alien worlds makes it sound like we're not one of the 100 billion, which we are.
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....)
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.
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.
We are the 0.0000001%...
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.
I think he's trying to say that its not necessary to say alien worlds, just say worlds.
If you just say worlds you have to say a billion and one. That's two extra words.
aren't all worlds, not our own, alien?
Yea, so 100,000,000,001 is total.
Sheesh, evil *and* a jerk. -- Jade
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.