Shortlist of Possible ET Addresses 136
An anonymous reader writes "Yahoo News is reporting that Astronomer Margaret Turnbull of the Carnegie Institution has released a 'top 10' list of potential inhabitable star systems. NASA is planning on using this top 10 list as the targets for their Terrestrial Planet Finder a 'system of two orbiting observatories scheduled for launch by 2020.'"
Keeping it secret (Score:4, Insightful)
Re:Keeping it secret (Score:1, Interesting)
But only after the financers have placed their bets on the stock market.
And if the transmission contains suitable material filed a few patents. (Or does LGM tech constitute prior art?)
Re:Keeping it secret (Score:2, Interesting)
And if the transmission contains suitable material filed a few patents. (Or does LGM tech constitute prior art?)"
I would like to think that the contract the private investors sign to be involved states that all information gained from transmissions are public domain. Then again the project might be desperate enough for money that they would allow the investors to keep control of what they recieve.
But, the most important thing is... (Score:2, Funny)
Re:But, the most important thing is... (Score:2)
Perhaps (Score:2)
Re:Perhaps (Score:2)
Re:But, the most important thing is... (Score:1)
of particular concern is who is notified first (Score:4, Interesting)
Then again if that's the only way we're gonna get these projects funded, perhaps these philanthropists should be rewarded for their risk taking.
Re:of particular concern is who is notified first (Score:5, Funny)
We all know that should be 'Hello world' ;)
Re:of particular concern is who is notified first (Score:3, Interesting)
> still the thought that a few private individuals will know first should give us
> pause.
It seems to me this is a venture like any other. You put your money where your mouth is, you take a risk, and if it pays off, you get a reward. Smart investors look for low risk, high reward; this particular investment I think is high risk, high reward. Fair's fair and good luck to them!
Re:of particular concern is who is notified first (Score:1)
Re:of particular concern is who is notified first (Score:1)
Best... crank first contact... ever!
Re:of particular concern is who is notified first (Score:3, Interesting)
I think you are underestimating the effect that just the knowledge that there are other intelligences out there would have. The "Hello there" message would be quite enough to roil stock markets, cause riots, etc. Tens of people have been killed in riots over cartoons l
Terrestrial Planet Finder has been cancelled... (Score:5, Informative)
http://www.spaceref.com/news/viewnews.html?id=109
So this list seems redundant. To bad, as it was NASA's most exciting project IMO.
But there is still ESA's Darwin [wikipedia.org], an essentially identical project, which is still scheduled for a 2015 launch as far as I am aware.
Re:Terrestrial Planet Finder has been cancelled... (Score:3, Interesting)
And "cancellation" and "postpone indefinitely" mean different things. I think that TPF is listed as the latter (but correct me if I am wrong, of course!).
Propaganda ? (Score:3, Insightful)
Re:Terrestrial Planet Finder has been cancelled... (Score:2)
If you are trying to imply something then I don't get it.
And to me, "cancellation" and "postpone indefinitely" sound very much like the same thing; the two terms seems to me to be equivalent in terms of actual consequences. Hence I think that translating NASA's "postpone indefinitely" into "cancelled" is not misleading. (see also the article I linked)
Re:Terrestrial Planet Finder has been cancelled... (Score:1)
As have the Keck Outriggers, which would have... (Score:2)
TPF has been delayed, not cancelled (Score:3, Informative)
As Michael Griffin explains in Griffin Builds Hopes For Terrestrial Planet Finder And Hubble Rescue Missions [spacedaily.com].
The short reason is that the Crew Exploration Vehicle takes priority.
TPF defered not cancelled (Score:3, Informative)
The Terrestrial Planet Finder has been cancelled:
The article you linked says it has been defered. The cancelling part was the author's embellishment. This is happening because NASA administrator Griffin is responsibly trying to balance the retirement of the space shuttle, the completion of ISS, and the development of the CEV. Something has to give, it is space science. They've had a heck of a run. Look on the bright side. Extrasolar science is advancing rapidly without a TPF. The extra few years until i
Re:TPF defered not cancelled (Score:2)
For more information on the cancelled science mission see The planetary Society [planetary.org] which has been fighting Congress for science mission funding for years. You don't have to be a member to help out.
Lobbying against NASA (Score:2)
Astronomy and planetary science have been well funded for 15 years. There great new missions in the pipeline. Progress continues to be made in extrasolar studies. NASA space science is as healthy as it has ever been. The Planetary Society is nothing more than a greedy lobbying organisation that takes with both hands. They will never be satisfied. They are no different from AARP or AFLCIO. I hardly consider their views on the direction of the US space program to be mainstream. I would not dream of helping th
hmmm (Score:5, Interesting)
Now, is it just me, or does the idea that life may well need some abnormal event to kick-start it in conflict with that very idea?
Perhaps include *some* of these systems?
smash.
Re:hmmm (Score:1, Interesting)
Re:hmmm (Score:2)
But the earth is only 4600 years old, so there's nothing preventing an intelligent designer from popping by these unstable systems every so often and re-Genisising.
(Why yes, this is flamebait, thanks for asking!)
Re:hmmm (Score:1)
Re:hmmm (Score:1)
Well, it's very unlikely that you find a planet that, for example, has its temperature constantly changing to carry an advanced form of life. Simply because it's unlikely to find there life that has lived under these bad conditions long enough to have evolved into some advanced form, etc..
It's unlikely, not impossible, but these guys at the NASA are just looking at the systems where life is the most
Instability: not for life, but for intelligence (Score:2)
The ruinous cost of a human brain can only be paid back in an environment that's variable enough to put a premium on adaptability. Otherwise "fitness" seems to map to "reproduce early and often".
Re:hmmm (Score:3, Funny)
You noticed that humans are composed of dark matter, didn't you. I mean, we aren't so bright...
Immigration? (Score:3, Interesting)
An open call for science fiction references if there ever was one.
Her criteria include a temperate zone that can support copious amounts of liquid water. If we're moving, I agree. There are chemical reasons we think life would be predisposed toward water but there could be different biochemistries. Any biochemists out there feel free to disagree and/or expound.
This story is also a good test of the slashdot equivalent of Godwin's law. How long until the usual sectarian debates spring up (and I don't mean MS)
Re:Immigration? (Score:5, Interesting)
I'll take that one. In a liquid water environment it's difficult to see how you'd end up with a biochemistry that wasn't nucleic acid, protein, carbohydrate and fatty acid based. By observation life on earth seems to have explored just about every type of possible molecular structure that carbon/hydrogen/oxygen + other minor elements can produce and if there were some other useful biological molecule then it's difficult to imagine why it's not been 'discovered' and exploited already. That's not to say that the details won't differ - I'd have thought it virtual certain that a mix of different nucleic acids and amino acids would be used in different combinations with a different genetics etc etc, but I'd expect life to be grossly similar on similar planets, just differing radically in the details.
Outside that I'm very unconvinced by non-water or carbon based life. Silicon just doesn't form complex enough molecules so that's out. The next best bet seems to me to me ammonia based.
Re:Immigration? (Score:2)
I'd be very astonished to learn that all life on all planets uses the same DNA/RNA combination we use. There almost certainly are other combinations of amino acids that can be used for the coding, and different chemicals for the backbone. It may be that DNA/RNA simply got started first and spread fast enough that the alternative
Re:Immigration? (Score:5, Informative)
We can even reasonably be a bit more precise about it. With proteins of the 20 amino acids in prime use a good dozen of them could be expected to turn up in an alien biochemistry just because they're the simplest that do the job. With the carbohydrates many are also a dead certainty - glucose, fructose etc. and polymers like chitin are certain to be just as useful to alien biochemistry as they are to ours. On the lipid front, wll lipids are lipids and our biochemistry uses just about everyone going anyway so there's certain to be major overlap.
Nucleic acids are more interesting though. I'd lay a bet on RNA just because the ribonucelic acids tend to form easily in prebiotic conditions. DNA is more suspect, particularly as life here can get along without it just fine. Nevertheless it's the next simplest step up from RNA so may be favoured against other varients. Of course which nucelic acids are actually used is open to chance, although it's noticable that the ones we have are among the simplest.
Beyond these broad categories though indeed it gets more speculative. Even so, some assumptions seem probable. For example if there is RNA/DNA then a triplet genetic code is likely, because as has been observed, a doublet code doesn't give you enough combinations to work with (but there is evidence that our early genetic code was doublet and we evolved the triplet later) whereas a quad code would be inefficient needing 33% extra DNA to code and more error prone.
Other things that might also be expected to turn up. For example porphorins (the building block of haem, chlorophyll and many other useful molecules).
Unfortunatly I guess we'll never know, unless we strike lucky on Mars or Europa.
Re:Immigration? (Score:2)
and nitrogen. Nitrogen's not exactly a minor element with organic compounds.
Other elements (like sulphur for amino acids, or magnesium for chlorophyll) are very, very rare, and I wouldn't be surprised if you could build a full biochemistry with just CHON - just much more inefficient than our current one. The one thing I'm not sure that life could build with just CHON is a photoreceptor - the metal-free pigments all seem to be accessory pigments only. This, actually, is an interesting p
Re:Immigration? (Score:2)
Incidently I life would manage to get by with scarer metals. There's a group of molluscs with vanadium-based blood, which is a couple of orders of magnitude rarer in the crust than iron.
Re:Immigration? (Score:2)
But photoreceptors and energy storage molecules I'm not so sure about. Everything uses ATP and every plant uses chlorophyll. I'm not sure life could really manage in a phosphorus/magnesium poor area.
Maybe not a big coincidence (Score:2)
A big coincidence, or a sign of Intelligent Design?
Re:Maybe not a big coincidence (Score:2)
Actually, no - CHON are the most abundant elements in the universe, not on Earth. Many of the other planets in the solar system are poor in one of CHON - Mars is very nitrogen-poor, for instance, and the Moon is very carbon-poor. Earth is tremendously silicon-rich, but we don't use it instead of carbon because silicon wouldn't work.
The reason that they're used for life has more to do with their chemistry than
Re:Immigration? (Score:2)
IANABC ... but, maybe it's just as simple as we can only conceive life in ways that are familiar to us? While it's possible that life could exist in forms we can't even guess at, we don't have any criteria to look
Locating Greener Pastures (Score:5, Insightful)
This would be a lot more motivating and captivating than scanning the heavens for shapes of creatures from mythology, which is no better than looking for pictures of Jesus or the Virgin Mary in a cheese sandwich.
Once we find something out there worth travelling to, then it would automatically spur thoughts of developing means to get there. Even if such dreams aren't possible due to the limits of known physics, it's still a noble and instinctive goal, like our grazing ancestors had in seeking greener pastures. Who knows where such thoughts might ultimatley lead?
Re:Locating Greener Pastures (Score:1)
Re:Locating Greener Pastures (Score:2)
A lesson for our times, indeed.
Re:Locating Greener Pastures (Score:2)
That's not what astronomers do. That's not even what amateur astronomers do.
The constellation-based naming system is just a convenient way of finding your way around the sky because it leverages the human mind's facility for pattern recognition and it's a billion times easier than trying to remember thousands of ascension and declination co-ordinates which change every minute.
The constell
Recent Articles on the Origin of Life (Score:5, Interesting)
Life on Earth 'unlikely to have emerged in volcanic springs' [royalsoc.ac.uk]
13 Feb 2006
"The latest findings of experiments to re-create the conditions under which life could emerge from chemical reactions suggest that volcanic springs and marine hydrothermal events are unlikely to have provided the right environment, a leading researcher from the United States will tell an international meeting tomorrow (14 February 2006) at the Royal Society, the UK national academy of science."
In the alternative Plos ran an interestin article titled Jump-Starting a Cellular World: Investigating the Origin of Life, from Soup to Networks [plosjournals.org] which touches on the front running theories on the origin of life.
Adresses ? those fools ! (Score:3, Funny)
Re:Adresses ? those fools ! (Score:2)
It's BT's directory services, they used ET as part of their millennium advertising campaign.
Why not? (Score:1, Funny)
At the rate we're going, by the time we actually need to get off this planet because we've hollowed it out and destroyed the O-Zone....
Congressman1: Alright, we're about to die. Any ideas?
Congressman2: We can up and move to another planet.
Congressman1: Great idea! Get us a list of inhabitable planets!
Sec
Razor blade star NUMA NUMA yay (Score:1)
by the time we actually need to get off this planet because we've hollowed it out and destroyed the O-Zone
Numa Numa [wikipedia.org] haters take note: If you destroy the O-Zone [wikipedia.org], you too will be destroyed.
Finding life == Online Dating (Score:2, Informative)
What exactly is the point? Life is out there, I like to believe, but until I can see, feel,
Re:Finding life == Online Dating (Score:3, Funny)
Re:Finding life == Online Dating (Score:3, Insightful)
I hate to break it to you, but the world will go on after you die. There will be people just as bright and interested in things like this as you are (or aren't).
Astroscience is about advancing the species, not the nation, not the corporation, not the individual, but humanity itself. In space are the answers to all of our questions (origins of life, divinity or lack thereof, the nature of sentience, pos
Re:Finding life == Online Dating (Score:3, Insightful)
Of course, we need to improve some more on artificial intelligence. We don't need something that can converse, but we do need something that can make decisions about proper behavior for unexpected events.
Re:Finding life == Online Dating (Score:2)
I think 30 years to get there is a little optimistic.
It took 26 years for Voyager to leave our Solar System. Even with ion-drive spacecraft (still in their infancy, and very experimental) I doubt we'd get anywhere near 1/6th the speed of light your 30 years would suggest.
Short of some
Re:Finding life == Online Dating (Score:2)
I figure that we have at least two more generations of remote detection methods before we'll have to send a probe to get more detail. Meanwhile, we might as well use them to get more detail, the more we know the better the probe can be. It's not like we're in a huge hurry right now.
Voyager's been on a ballistic course for most of it's journey, if I remember correctly. Yes, we do have
Re:Finding life == Online Dating (Score:2)
Not really. If you could get past the rabid enviroloons who shit bricks every time someone says the word 'nuclear', a relatively simply Orion-style probe could reasonably be expected to achieve a velocity of 10% or more of the speed of light in short order. And it could carry enough fuel to slow down for orbital insertion once it reached the target system, using that same power to boost one hell of a signal back to Earth about what it sees.
That means that a syst
Nuclear Contamination of Space (Score:2)
Seriously, I have to agree that the uber left-wing idiots against nuclear energy are clueless as to its potential. Of course I've already seen environmentalists complaining about the effects of open pit mining on the Moon damaging the environment... and studies to complain
Re:Finding life == Online Dating (Score:2)
As we don't even have such technologies in the theoretical stages, I'll say that it's at least a hundred years off. As long as it stays that way, we might as well send an STL probe.
What's the worst that could h
Re:Finding life == Online Dating (Score:2)
Why not? It's not like the human race would be sitting around doing nothing during that time. We just leave a note for the next generation reminding them to check the inbox every once in a while.
If we did get a response it would probably be more than just "Got your message, please reply."
Re:Finding life == Online Dating (Score:2)
No, it would probably be some sort if intergalactic smiley: %*&. An we'd figure that the pointy bits were probably teeth, and get all pissed at them, so we'd send them a snarky message back, and then it's just flame-flame-flame for a few millennia.
(Of course on the planet Arkthon IV you have to turn your head to the right rather than the left to read the smileys.)
Re:Finding life == Online Dating (Score:2)
(Of course on the planet Arkthon IV you have to turn your head to the right rather than the left to read the smileys.)
Except for the lefthanded smileys, a lot like slashdot. (-:
On the other Hand... (Score:2)
Best part of the whole thing is... (Score:5, Funny)
What about Zeta Reticuli (Score:1)
Re:What about Zeta Reticuli (Score:1)
Zeta1 Reticuli is number 57 on the list. Obviously, not in the "top 10". But Alpha Mensae is also on the list at number 31 and Tau Ceti actually made number 3.
Interestingly enough, All 3 of them are G class (Yellow) stars just like our own sun.
I wouldn't want to encourage science to chase after tabloid stories and urban legends, but it certainly does seem interesting.
Re:What about Zeta Reticuli - The actual 10 stars (Score:3, Informative)
Tau Ceti [solstation.com], 11.9 light years
Alpha Centauri B [sunrise.ch], 4.35 light years
Epsilon Eridani [solstation.com], 10.5 light-years
Epsilon Indi A [solstation.com], 11.8 light-years
http://www.glyphweb.com/esky/stars/keid.html [glyphweb.com]">Omic ron 2 Eridani, 16 light years
Beta Canum Venaticorum [astronexus.com] - 27.31 light years
HD 10307 [solstation.com], 41.2 light years
HD 211415>/a>, 44.4 light years [alcyone.de]
18 Scorpii [solstation.com], 45.7 light years
51 Pegasus [uoregon.edu], 40 light years
There is also a top 50 list [astronexus.com]
Re:What about Zeta Reticuli (Score:2)
I can't say I believe this story but it's interesting enough. It would be stunning if it's true.
Assuming it's true, one take-away from this story was that the beings living there came from somewhere else. It's not their "home world" where their form of life developed and evolved.
Most of our scientists -and nearly all the "probable habitable planets" charts seem to always stick to looking at stars that might support life RIGHT NOW. If thi
The human drive for greatness (Score:4, Funny)
Kirk said it best: (Score:2)
Re:The human drive for greatness (Score:2)
Red vs. Blue Quote (Score:1)
just 10? (Score:4, Funny)
Phone numbers? Please. (Score:3, Funny)
Re:Phone numbers? Please. (Score:2)
Grasp of reality... slipping. Sentsix, you really ought to keep taking your medication. ;)
Now there's a marketing ploy (Score:4, Funny)
Crap. You can bet the aliens will end up with Windows on 90% of their desktops before they even hear of Linux.
Bill Gates Phone Home (Score:2)
Does anyone else find it disturbing that funding for basic science is suffering from such severe cuts? It s
Life in stranger places (Score:1)
You never know what situations you might create life in.
Re:Life in stranger places (Score:2)
Just look at some of the life that grows in a college student's dirty laundry pile. Scary.
You never know what situations you might create life in.
Funny you should say that. My Mum once bought this round rack thing with three bottles in it, meant for fancy cooking and what not.
In one of the bottles was, if I remember it correctly, balsamic vinegar and extra virgin olive oil.
Because of the densities of the liquids, they tended to settle, light on top, dark below.
Long story short, Mum never
Useful links about the project (Score:5, Informative)
Here [nasa.gov] or here [astrobio.net], a very nice article on the project, "Margaret Turnbull and Jill Tarter have a new list, called HabCat: A Catalog of Nearby Habitable Stellar Systems." (2003) Interview included.
Interesting that starting with the Hipparcos catalog of 120,000 stars and skipping all with major problems for life ("cataclysmic, eruptive, pulsating, rotating, or X-ray stars", low metal content systems, rotating too fast or too much UV or bad size or composition), left 1 star in 6 still potential life bearers.
Wiki on HabCat [wikipedia.org] and Turnbull [wikipedia.org]. The Turnbull page has a link to a PDF, which is a very interesting scientific paper about how the list of habitable stars was made.
Wiki article [wikipedia.org] on the Terrestrial Planet Finder, which uses Turnbull's list of 5000 candidates within a 100 light year radius. List of Top 100 candidates. Note 18 Scorpii at 46 light years is number 62 in the list, and 37 Geminorum is not listed.
The highest ranked 2 candidates in that list are just 4 ly away from Earth, at Rigil Kentaurus, and then Tau Ceti at 12 ly. There is one at 3 ly and some others at 19, 20, 24 ly too.
Allen Telescope Array [seti.org]
Turnbull's top 10 list includes 51 Pegasus, where in 1995 Swiss astronomers spotted the first planet outside our solar system, a Jupiter-like giant.
Others include 18 Sco in the Scorpio constellation, which is very similar to our own sun; epsilon Indi A, a star one-tenth as bright as the sun; and alpha Centauri B, part of the closest solar system to our own.
Re:Useful links about the project (Score:2)
See: http://www.astronexus.com/scripts/eos/eos_star.ph
angel'o'sphere
Re:Useful links about the project (Score:2)
Re:Useful links about the project (Score:2)
Rigil Kent is more commonly known by its Bayer designation, Alpha Centauri [wikipedia.org].
Re:Useful links about the project (Score:2)
Well, we don't want to send a spaceship there. Not yet, anyway. We want to wait for the 25% boost to thrust you get with Fusion Power, and for the 50% discount on construction of it that you get once you've built the Space Elevator.
We'll want to make certain of security, and conduct thorough psychological assessments on the people we send, too. You don't want to risk there being a major quarrel among the crew enroute - if that ha
Microsoft cornering the ET OS market? (Score:2, Insightful)
Don't be scared (Score:2)
Fast way to narrow it down (Score:4, Funny)
Terrestrial planets maybe. Intelligent life not! (Score:4, Interesting)
Lets do the math. Universe, ~13 billion years old. Earth, ~5 billion years old. Time to develop first sun-like stars perhaps 1 billion years. So there is a reasonable chance that there are (or were) Earth like planets up to 7 billion years older than Earth (at least around stars slightly smaller than the sun which age more slowly). There are some systems with younger Earths (*much* younger for those systems currently in the process of planetary formation). Lineweaver's group has worked on this and has concluded that ~70% of the Earth's in the galaxy are older than ours -- many of them by billions of years.
Based on this it is unlikely that either TPF or SETI (based on its current approaches) will discover "intelligent" life. The statistics dictate that you only have perhaps a 5000 (years) / 12,000,000,000 (years) chance (less than 1 in a million) of finding a planet which hosts "intelligent" life as we know it.
For those systems with terrestrial sized planets and those with water TPF is a reasonable effort -- it might manage to detect water and if lucky atmospheric composition that could hint at life. However pointing the SKA (or any other radiotelescopes) at the stars in the list provided are highly unlikely to be successful because they assume intelligent civilizations which are currently at (and remain at) our stage of development. (This changes the statistics to about 1 in a billion.)
The reasons for this are as follows... Whether you believe in steady state growth (Dyson's assumption in 1960), or exponential growth as "The Singularity [wikipedia.org]" concept proposes the bottom line is that it seems very unlikely that a civilization would actively choose to remain at our state of development (i.e. zero growth for millions or billions of years). If you choose the steady state model the time to develop to a Dyson Shell is measured in a few hundred to a few thousand years. If you choose the singularity model then the time to develop a Matrioshka Brain [aeiveos.com] (also here [wikipedia.org]) is measured in decades. Once either of those states is reached the star goes "dark". So the star list is useless (to either the TPF mission or SETI) for identifying locations of intelligent civilizations with capabilities even slightly beyond our own.
Robert Bradbury
Notes:
For the above calculations I chose 5000 years as the longevity of humans with a reasonable level of technology development. One could limit it to smaller time frames (~100 years for radio or 40-50 years for lasers or rockets). TPF has a much greater chance of being successful than radio or optical SETI because it is working with a much larger time window. Water world longevities range from 100 million to many billion years if they restrict themselves to sun-like (
So much of SETI is pure pseudo-science (Score:2)
Re:So much of SETI is pure pseudo-science (Score:2)
Re:So much of SETI is pure pseudo-science (Score:2)
I heard someone call it "The Rapture of the Nerds" which I think is more apropo.
Re:So much of SETI is pure pseudo-science (Score:2)
There's nothing special about aging and death. It too will yie
My roommate looked into it already (Score:1)
And? What are the ten systems? (Score:2)
Can anyone post a link which INCLUDES the ten systems/stars and is not jsut babble?
angel'o'sphere
But... (Score:2)
Bruce
Correction -- Two "Top 5" Lists, and more... (Score:5, Interesting)
What she announced yesterday were TWO "Top 5" lists. The first list includes the top 5 recommendations for a SETI search:
beta CVn
HD 10307
HD 211415
18 Sco
51 Pegasus
The second list includes the top 5 recommendations for the TPF to examine for Earth-like planets:
epsilon Indi A
epsilon Eridani
omicron2 Eridani
alpha Centauri B
tau Ceti
Why the difference? Well, the second list is of much closer stars, and much more likely to have planets that TPF can find and image. The first list has stars that are a bit farther away, but are, generally speaking, more like our Sun.
And here's a useful link:
http://www.aaas.org/news/releases/2006/0218habita
Bruce
Re:ummm (Score:1)
Re:ummm (Score:2)
Re:Inhabitable? (Score:1)
You must not have followed too much of human history...
Re:ET Life (Score:2)