Space water discoveries enhance odds for early life
|
A cross-section of the Zag meteorite
| |
September 8, 1999
Web posted at: 5:18 p.m. EDT (2118 GMT)
By Robin Lloyd
CNN Interactive Senior Writer
(CNN) -- Back to back discoveries of water trapped in one meteorite and likely water in a second suggest that the liquid of life was far more abundant in the early solar system than previously thought, scientists say.
NASA researchers have cracked open two meteorites in recent months and definitively found in one -- and possibly found in a second -- tiny pockets of briny liquid water from deep space.
In space, that water was probably unleashed during a warming event that lasted 10 million to 20 million years and could have freed up enough of it to shape rocks on planets and start up organic reactions necessary for life, said Michael Zolensky, a space scientist at NASA's Johnson Space Center.
"We always knew there was some water available in the early portion of the solar system," Zolensky said. "We didn't know there was this much. The new finding suggests that there was a lot more than we thought. It might mean conditions for life were more hospitable than we thought."
Zolenksy and his colleague Robert Bodnar at the Virginia Polytechnic University will conduct tests on the so-called Zag meteorite in coming weeks to confirm their strong suspicion that the space ball contains liquid water. Zolensky said he is "99.9 percent sure" he is right.
"You can see little bubbles of fluid floating around sitting in sodium chloride like in the other meteorite," he said.
The droplets are about one-tenth the width of a human hair.
Zag, weighing in at 300 pounds, landed last year in a remote area of Morocco.
Meteorites provide clues
Meteorites are thought to record the conditions of the early solar system so the meteorite findings excite those studying how the solar system formed and what conditions were at the time -- including conditions for liquid water and life.
Nearly two weeks ago, Zolensky's report that a meteorite that fell in Texas in 1998 contains liquid water was published in the journal Science.
|
This image shows magnified halite crystals up to 3 millimeters (less than a tenth of an inch) in diameter inside a meteorite found in west Texas. The presence of water inside the crystals was confirmed using several forms of scientific analysis
| |
|
Then, last weekend, Zolensky told sellers of Zag at a Texas mineral show that he found it also appeared to contain water. That prompted the premature reports about liquid water in the second meteorite, although Zolensky said he also had announced his preliminary findings at a meeting of the Meteoritical Society in South Africa last month.
Scientists have found evidence of water or evaporated water embedded in minerals within meteorites before, but never reported liquid water in a meteorite until the Science story came out.
That's partly because liquid water in meteorites is thought to evaporate or react with its environment soon after the space rocks hit Earth, said Everett Gibson, a JSC space scientist who studies the Texas meteorite.
Now, Zolensky suspects that most meteorites contain liquid water, at least initially.
Chondrite meteorites, such as the one found in Monahans and the Zag, are thought to comprise some of the most primitive ingredients from the early period of the solar system, and the water in the crystals could date as far back as 4.5 billion years.
Poor man's space probe
Meteorites are a "poor man's space probe," Gibson said, encouraging those who find think they have found meteorites to report them quickly. But 98 percent of what lay people think are space rocks are actually slag or pieces of metal from fires or house explosions, he said.
Gibson initially helped recover pieces of the Texas meteorite, which fell in two pieces about the size of grapefruits.
One piece landed behind five boys playing basketball and generated a fireball that could be seen for a 120-mile radius. After donating part of that meteorite to Arizona State University, the boys sold the rest for $23,000, Gibson said.
While astronomers have long thought that water flowed through asteroids and other bodies formed at the beginning of the solar system, the Monahans meteorite's liquid cargo, and now possibly the Zag's, offer the first chance to actually study it in a lab.
"We know that water has been so important in the evolution of planets in our solar system," Gibson said.
"And here is our first liquid water, in the Monahans meteorite and possibly the Zag, that was around at times when the solid phases of the early solar system were brought together to make our planets," he said.
"It has been preserved for us and it's the first time we have seen liquid water that is that old."
RELATED STORIES:
NASA reveals site for next Mars touchdown August 25, 1999
Martian spring reveals frozen water at south pole August 3, 1999
Crash landing on moon part of NASA experiment July 31, 1999
Space Briefs: Dawn to dusk in five minutes July 26, 1999
RELATED SITES:
NASA Jet Propulsion Laboratory
Houston Chronicle
Note: Pages will open in a new browser window
External sites are not endorsed by CNN Interactive.
|