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Scientists Confront 'Weird Life' on Other Worlds
By Leonard David
Senior Space Writer
posted: 07:00 am ET
07 May 2004

 

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.

http://www.space.com/scienceastronomy/astrobiology_nrc_040507.html


In late March, the SETI Institute education team was at the National Science
Teachers Association (NSTA) meeting in San Diego, CA along with about 14,000
other science teachers. It's a good thing that these NSTA meetings coincide with
spring break, or no science would be taught in U.S. schools during that week
every spring. 

I had a long conversation with a high school science teacher about teaching
science in a world where his students are continually exposed to pseudo-science,
the stuff they learn from watching television and reading the tabloids. What do
they believe is real? The face on Mars, alien autopsies, Area 51 in the Nevada
desert as alien storage quarters, the "non-landings" on the Moon, UFO�s, alien
kidnappings--these are all the grist of great story telling and speculation in
the media. It is easy for uncritical kids (and adults) to believe the "evidence"
of alien beings and encounters when it is carefully gift-wrapped by creative
television producers who crank out dramatic programs depicting these events with
well-trained actors and elaborate sets. Of course, these are the same folks who
bring us fantastic science fiction films which we ALL know are entertainment,
not science education. Or at least I function under that illusion. 


The pseudo-science accounts are carefully filmed and professionally narrated for
television as "documentaries" about mysteries, or unexplained events. All aim to
convince the public that aliens have been here or nearby on the Moon or Mars,
and that all of the "evidence" is being covered up by a grand conspiracy of
seriously un-fun people in the government, universities, and research
organizations. Folks like me. Denying, providing alternative explanations, or
criticizing the "evidence" somehow "proves" there is a cover-up. 

About 50% of the American public believes that UFO's are real, and what they
mean by "real" is that UFO's are piloted by aliens from some distant world, not
Earthlings from the local Air Force Base or actors in Hollywood costumes. Think
about that, and then consider teaching space science and astronomy in this
social context.

Take the face on Mars. The first photograph of this bumpy mesa was snapped by
the Viking Orbiter, and released by NASA to the public on July 31, 1976. 

It is an intriguing image, and certainly does look like a face. In fact, since
then, this "face" on Mars has inspired a whole library of books and groups of
true believers that now find "evidence" of a "Pyramid" and an "Inca City" as
well. All, of course, photographed by Viking but "covered up" by NASA officials.
Note that all of the publications help to put bread on the table and pay the
rent for the creative folks churning out such books, articles, and tabloid
stories about "the face." 

Now, imagine being a science teacher with a classroom full of 15-year old
students who believe the television accounts of the face on Mars, cities on the
Moon, alien autopsies, etc., and you are teaching your unit on space and
astronomy. A careful excursion through the characteristics of the planets and
their moons interests your students; the red spot on Jupiter would hold at least
3 Earths, a cool factoid, but it doesn't grab them. The face on Mars does. And
this was what I discussed with the science teacher at NSTA. 

The face on Mars is a teachable moment. Turn your students into scientists.
Present the evidence for students to consider. There is the Viking photograph,
taken in 1976 and the Mars Global Surveyor (MGS) photographs taken about 25
years later. Ask the students what they see in the 1976 photograph. Like
everyone else, they will see a face. I see a face in that photograph too. Humans
interact with the natural world by organizing perception into recognizable form.
Who has not watched clouds on a summer day and seen patterns that look like
horses, dragons, beautiful men/women, ships, and such? In the early part of the
century astronomer Percival Lowell was convinced that he saw canals on Mars
through his telescope in Arizona. Subsequently, other observers and photography
of Mars proved that his mind was connecting broken features into lines, which he
perceived as canals. It was all in his mind, not on Mars. Humans are pattern
seekers, and seeing familiar forms in strange places helps us to organize our
perceptions of the natural world. There was a rock formation near my childhood
home in the Sierra Nevada Mountains that looked like a bear, but I never assumed
that it was carved by unknown beings to make me believe in them or to ponder
bears. I understood that it was jagged granite, and the fact that it looked like
a bear was a coincidence. I also had to stand in the right place to see the
"bear"; otherwise, it just looked like a mountain peak. Like the bear, to see
the face on Mars, you have to "stand" in the right place, and at the right time
of day. 

Move forward a couple of decades. We've returned to Mars. We have new, higher
resolution photographs of the same mesa taken by MGS and posted to the web by
Malin Space Science Systems, the designers and builders of the camera onboard
MGS. These are detailed, new views, including views from different places at
different times of the day. The raw data from MGS is image-processed to bring
out the details on the mesa, and a clear explanation for how scientists
accomplish this work helps students to understand that there is not a cover up.
Send your students there for the evidence. What does the mesa look like when
seen more clearly, more closely?

The shadows cast by the low Sun angle in 1976 created a lovely illusion, a giant
face-like mesa on Mars. The new images, taken by MGS reveal the "face" as a
rocky mesa, one of many in the Cydonia region of Mars. It looks a lot like mesas
in the western region of the United States. In fact, it looks a lot like other
mesas in that same region on Mars--similar in size, dimension, and height. It's
an ordinary feature on Mars, not a gargantuan piece of artwork left to make us
ponder whether Mars had been visited by alien artists who sculpted on a grand
scale. But, don't ask students to "believe" in science, provide the evidence,
and allow them to critically consider what we now know about the "face" on Mars.
Give them the same opportunity granted the space scientists that took the images
with Viking and with MGS. 

Finally, ask yourself and your students how much money people made and continue
to make from selling pseudoscientific accounts and films to the gullible public.
That discussion might reveal why the "face on Mars" is so persistent.