Scientists Confront 'Weird Life' on Other Worlds

SPACE.com ^ | Friday, May 7, 2004 | Leonard David

[Momaw Nadon]

WASHINGTON, D.C. – What are the limits of organic life in planetary systems? It’s a heady question that, if answered, may reveal just how crowded the cosmos could be with alien biology.

A study arm of the National Academy of Sciences, the National Research Council (NRC), has pulled together a task group of specialists to tackle the issue of alternative life forms -- a.k.a. "weird life".

To get things rolling, a workshop on the prospects for finding life on other worlds is being held here May 10-11. The meeting is a joint activity of the NRC’s Space Studies Board's Task Group on the Limits of Organic Life in Planetary Systems and the Committee on the Origin and Evolution of Life.

Sessions on Earth biology, possible Mars habitats, looking for life on Europa -- a moon of Jupiter -- as well as on Titan, a natural satellite of Saturn, are featured topics on the wide-ranging meeting agenda.

Alternative chemistries

The newly formed study group has some big issues to get their arms around.

Possible alternative chemistries for life are to be evaluated, with an eye toward the prospect that non-standard chemistry may support life in known solar system and conceivable extra-solar environments.

Additionally, the task group is to define broad areas that might guide NASA, the National Science Foundation, and other relevant agencies and organizations to fund efforts to expand scientific knowledge in this area.

Overall, the programmatic goal of the study is singling out research avenues that will appraise the likelihood of "non-terran" life and the potential cost needed to find it. From this will come a recommendation "whether the likelihood of finding non-terran life is sufficiently low that NASA should ignore its possibility, or sufficiently high that it should pursue it," according to a study document.

"This is the first NRC project I have been involved with where scientists have actively been volunteering to serve on the committee. We usually have to corner candidates and then start twisting arms," said David Smith, Study Director for the NRC’s Space Studies Board.

"I have been struck from the very beginning that this was a project that could easily be dismissed as science fiction," Smith said. "However, all the scientists we have spoken to about this have required very little persuasion that this was a worthwhile project."

Boxed in beliefs

"We need to get a real understanding of what carbon is capable of in terms of life," said Michael Meyer, Senior Scientist for Astrobiology here at NASA Headquarters.

"We don’t want to end up just focused on only looking for DNA-type molecules…but we do want to look for anything carrying information that is carbon-based."

Meyer said the meeting will bring together some of the brightest minds. Their duty is to think outside the biological box that is the norm. Those discussions can help NASA build the right tools that have the potential of finding something unexpected, he said.

"You have to keep in mind…we know what life is on this planet and we still haven’t figured out how it got started. We have the basic ingredients…but it has proven to be a difficult problem for something that we know exists," Meyer said. "So if you’re going to start looking at things that we don’t know exist, you don’t want to try every possible scenario. You want to make sure you look for things that are reasonably possible."

Search for life…on Earth

There are two things that astrobiology does, Meyer said. One is that it forms the intellectual foundation for our understanding of the potential for life elsewhere in the universe. Part of this intellectual effort is to determine -- as is the case for Titan, a moon of Saturn -- whether or not life is possible there, theoretically.

The other half of the astrobiology effort, Meyer said, is to help guide what kind of life-detection instruments should be made.

"We’re going through a tremendous biological boon in learning so much about life on this planet. A lot of this advancement is due to remarkable techniques that have been developed that are extremely sensitive, but also highly specific," Meyer said.

"But that very sensitivity, because of its specificity, makes it almost useless in the quest to look for life elsewhere. That is, unless life elsewhere is made of exactly the same building blocks that were made out of and using similar sequences. So what we need to do is come up with more general ways to look for life…but increase the sensitivity in order to find that life," Meyer noted.

There is an interesting twist to the search for life elsewhere in the cosmos. You might stumble on previously unknown life right here on Earth.

"If we come up with techniques, knowing the organisms that we’re looking for, we might find some organisms here on Earth previously not known, much less finding things on other planetary bodies," Meyer said.

Weird worlds

"I think this kind of topic has always grasped human imagination," said Dirk Schulze-Makuch, Assistant Professor in the Department of Geological Sciences at the University of Texas, El Paso. "Now, finally we begin to have some understanding what kind of expectations and constraints on possible extraterrestrial life are reasonable," he told SPACE.com.

The timing is especially suitable, Schulze-Makuch said, because the NASA Cassini spacecraft will arrive in the Saturnian system in July, with Europe’s Huygens probe to be released onto Titan in early 2005.

"Titan is the ‘weirdest’ of planeatary bodies in our Solar System -- meaning different from Earth -- possessing hydrocarbon surface bodies and methane rain. Thus, if life would have gained a foothold on Titan with environmental conditions so different from Earth, it should be ‘weird’ indeed, and should function differently in many ways than we experience life on Earth.

Schulze-Makuch will take part in the upcoming workshop, outlining possible microbial habitats and metabolisms on Titan.

Universal surprises

"This is an important workshop," said Jonathan Lunine, Professor of Planetary Sciences and of Physics, and chair of the Theoretical Astrophysics Program at the University of Arizona in Tucson. He is a guest presenter at next week’s meeting.

"In the search for life elsewhere in the solar system, we tend to plan for life as we know it…even down to the nucleic acid bases or base sequences used in organisms elsewhere," Lunine said. "What if they don't use DNA? Or RNA? Or linear information-bearing polymers? Do they have to use liquid water as the universal biosolvent?" The universe has surprised us before with its variety, Lunine added, in spite of the simplicity and small number of fundamental physical laws.

"Yet our imagination hasn't been very good at envisioning how strange or unexpected life might be," Lunine concluded.

[Momaw Nadon]

FYI and discussion

[cripplecreek]

Ive allways liked the question "If we saw life would we recognize it?" We tend to think within our own sphere of knowledge. Just because life on earth is carbon based doesn't mean life elswhere can't be copper or helium based.

[thoughtomator]

They can do the field studies in the East Village... now THAT is "weird" life!

[IronJack]

I would think that the first question this group would have to answer is "What is life?" If they're limiting themselves to carbon-based genetic code, they may be entering into the project with a willful myopia.

[bannie]

Because I have no scientific background, I wonder why "carbon based" is the only point of interest. Might'nt there be other bases for life forms?

[bannie]

Just what I thought.

[AntiGuv]

Ping!!

[cripplecreek]

Think about it. The possibilities are endless. Of the planets we've detected around distant stars at least one is 4 times the size of Jupiter but orbits its sun at a distance equal to earths. Any life that developed on it would have to overcome enormous gravitational forces and likely radiation. But that doesnt mean it can't.

[bannie]

I watched Star Trek. Not all lives are carbon based.

:-)

[null and void]

Just because life on earth is carbon based doesn't mean life elswhere can't be copper or helium based.

Copper doesn't form large molecules. Helium is inert, doesn't bond with anything.

Sulfur and silicon, maybe...

[trickyricky]

You have to keep in mind…we know what life is on this planet and we still haven’t figured out how it got started

It was created by the Creator of the Universe.

[Lando Lincoln]

Weird Life?...Just check out the left side of the aisle.

Lando

[PatrickHenry]

PING. [This list is for the evolution side of evolution threads, and some other science topics like cosmology. FReepmail me to be added or dropped. Long-time list members get all pings, but can request evo-only status. New additions will be evo-only, but can request all pings. Specify all pings or you'll get evo-pings only.]

[Eric in the Ozarks]

Coal people ?

[William Terrell]

The other half of the astrobiology effort, Meyer said, is to help guide what kind of life-detection instruments should be made.

The best life-detection instrument is fried chicken. Send a box, with light sensitive cells embeded in the legs and breasts, to any planet to be tested. If it is eaten, there is life, if not, there is not.

[cripplecreek]

Crab people live!!!! I saw them on south park once.

[Maceman]

[Momaw Nadon]

Ping!

[Momaw Nadon]

[cripplecreek]

PAAAAIIINNNNNN!!!!!!!! THE PAAAIIINNNNN!!!!!!

[whereasandsoforth]

It is so romantic to think of life elsewhere besides earth. It takes an "open mind" to see the possibilities. Why is it nor just as open-minded to assume there is no living forms within our physical area of the universe?

God, Who is and will always Be a mystery, may have several earth-like experiments going on in the vastness of the endless universe. If that is true, my open mind tells me they are far enough apart that they will never know the existence of the others.

Except for earth, our solar system and beyond, within our reach, is as dead as my Aunt Matty. It takes an open-mind to come to this conclusion.

[ColoradoSlim]

I think the recent discovery of trace amounts of methane on Mars is fascinating and revealing. Trace amounts of methane should strongly point to bacterial activity, past or present. I don't accept the hydrocarbon contamination by comets crap. It will be a very shot time before life is confirmed to have existed on Mars, or is there presently. I refuse to believe that the architect of this beautiful and perfect universe would leave it unpopulated save for one tiny planet in an obscure solar system residing along side billions of stars in an unremarkable galaxy, etc. etc.

[Alamo-Girl]

Thanks for the ping!

[cripplecreek]

As a methodist ive never run into a conflict between evolution and creationism. The fact that life was created out of dead elements is pretty amazing to me.

[hosepipe]

[ What are the limits of organic life in planetary systems? It’s a heady question that, if answered, may reveal just how crowded the cosmos could be with alien biology ]

If evolution is a fairy tale for adults. This could be merely rumors about the fairy..

[Physicist]

Why is it nor just as open-minded to assume there is no living forms within our physical area of the universe?

Because A) there's only one way for it to be lifeless, and many ways for it not to be, and B) we exist, therefore we know life is possible.

[Skywalk]

"You are ugly bags of mostly water."

[ColoradoSlim]

Perhaps one might argue, that from God's glorious "creation", "evolved" our amazing and beautiful universe.

Many of the world greatest scientists of the last several centuries were Christians.

[PatrickHenry]

Many of the world greatest scientists of the last several centuries were Christians.

Yes. And all of the great thinkers in Classical Greece were pagans. Poor ol' Zeus, he gets no respect these days.

[Reeses]

"What is life?"

A blade of grass is a life form. At some point computers will have to be included as well. What's cool about that is we are their God. Will they worship us someday or be embarrassed?

[van_erwin]

What's the "East Village?"

[Momaw Nadon]

[van_erwin]

A) there's only one way for it to be lifeless, and many ways for it not to be,

Actually, there are a nearly infinite number of ways for it to be lifeless, and a very (relatively) small number of ways for life to exist. Even for the Universe to exist at all required such a staggeringly improbable set of conditions that it's the greatest of all miracles that it came to be.

[ServesURight]

Starship Troopers BUMP.

[Kenny Bunk]

Amazing how NASA scientists may be finally catching up with Robert Heinlein.

[BlazingArizona]

We tend to think within our own sphere of knowledge. Just because life on earth is carbon based doesn't mean life elsewhere can't be copper or helium based.

our search for life centers on carbon because of all elements, carbon is the most flexible at linking atoms of itself to form complex structures, from the benzene ring to buckyballs. Boron and silicon have a subset of this same power, so it is remotely possible that we will eventually encounter silicon-based life out there. There is a still higher probability that we will create it ourselves.

[DoctorMichael]

"....copper or helium....."

The Horta: THIS is the example that immediately came to my mind as a proposed Silicon-based life-form.

Actually, there was some thought that went into the writing of this particular Star Trek episode...........

Silicon occupies the same "column" as does Carbon on the Periodic Chart of Elements meaning that it contains the same electronic configuration and therefore has similar chemical properties.

[Michael Barnes]

ping..

[Momaw Nadon]

Silicon life might not look like animated crystals, as in this drawing from Dickinson and Schaller. Structural elements could well be in threads, like fiberglass, connected by tensor elements to create flexible, delicate, possibly even filmy structures

[DoctorMichael]

"....silicon have a subset of this same power....."

See my Post #37. I tried posting an accompanying Periodic Chart but it didn't work for some reason. You are essentially correct, just using the wrong terminology (ie. "subset of this same power" = "chemical properties").

Google a 'Periodic Table' to check me ('C' is right above 'Si').

[Mr. K]

OK, how did you make a post that does not have a "To " indicating who you are replying to

[ColdSteelTalon]

If its "weird life" don't you need "WEIRD SCIENCE" to study it???

[Momaw Nadon]

[SedVictaCatoni]

At some point computers will have to be included as well. What's cool about that is we are their God. Will they worship us someday or be embarrassed?

Their fundamentalists will probably proclaim that we created each one instantaneously, and consider the idea that we assembled each slowly through engineering as heretical.

[Momaw Nadon]

OK, how did you make a post that does not have a "To " indicating who you are replying to

Just make the "To:" field blank.

[DoctorMichael]

".....from God's glorious "creation", "evolved" our amazing and beautiful universe....."

I could not agree more! Thank you for posting THIS statement BEFORE the usual crowd shows up and spins the Thread into oblivion. Furthermore:

"......Many of the world greatest scientists of the last several centuries were Christians......"

Spot on.

[EggsAckley]

Are you implying that Gerrald Nadler is a life-form?

[DoctorMichael]

Thanks! I used the right HTML code copied from a 'HTML Sandbox' Thread I have bookmarked, but it didn't work. Oh well.

Notice 'C' (Element #6) is right above #14 (Silicon) indicating these elements have the same electronic configuration.

[Momaw Nadon]

[ColoradoSlim]

I don't have many problems with Greek "classical" thought. Much of our present day science and Western culture has is very roots grounded in ancient Greece. We plan on teaching our children Greek as well as Latin when they are old enough.