Posted on 03/01/2004 2:08:45 PM PST by vannrox
NASA will hold a press conference Tuesday to announce "significant findings" about water on Mars based on evidence from its Opportunity Mars rover.
"It's going to be the most significant science results that we've had from the rovers, and it's bearing on their primary mission," NASA spokesperson Don Savage told SPACE.com. That mission is to find signs of water that might support life.
Will the announcement change how we think about Mars?
"Anything of a significant nature has that possibility," Savage said. "Sure."
If there is liquid water presently at the surface of Mars, as several lines of rover evidence have hinted, then most scientists agree there is the possibility that life could exist. Water does not mean life, but it is the key ingredient that makes life possible.
Few scientists doubt that Mars was once warmer and wet. And tremendous amounts of water are locked up as ice in the polar regions. The main question is whether any of that water remains at the surface in liquid form.
Opportunity and its twin, Spirit, are exploring opposite sides of the planet near the equator.
A SPACE.com story Sunday revealed a "palpable buzz" among rover scientists at the Jet Propulsion Laboratory (JPL) in Pasadena, from where the rover mission is run. Sources indicated that a coherent picture of the geology of the rover landing sites was emerging.
Speculation that the announcement might involve any discussion of biology has not been confirmed.
Until now, all rover science news has been revealed at press conferences held in Pasadena. A routine had been established and the next press conference was slated for later this week. Sources indicated a major press conference might come next week. But NASA rushed to set up Tuesday's press conference at NASA Headquarters in Washington, DC.
"We didn't want to sit on this information for a long time," Savage said, adding that the scientists felt they "had gotten the information they needed."
The panel assembled for the press conference includes top brass and a cast of important science characters.
Speakers will include Ed Weiler, Associate Administrator for NASA's Office of Space Science, Jim Garvin, Lead Scientist for Mars and the Moon, Cornell University's Steve Squyres, the Mars Exploration Rover (MER) Principal Investigator, and MIT geologist John Grotzinger, among others.
The press conference will take place at 2 p.m. ET and will be carried live on NASA television.
Opportunity has been investigating the soil and a rock outcropping in a shallow depression at its Meridiani Planum landing site, which may once have been the site of a giant lake or ocean. The rocks are layered and may have formed as sediments settled in the bottom of an ancient lake or ocean, or as part of a river bed, but that is only one hypothesis.
Both Opportunity and Spirit have found sticky, clumping soil that scientists already said could contain water. Only small amounts of water, perhaps sucked from the atmosphere, would be needed to mix with salt in the soil and create a brine, which could exist in liquid form even in the frigid environment of Mars.
Opportunity also appears to sit amid a field of hematite, a mineral that typically -- but not always -- forms in the presence of water. The rover has also found countless BB-sized beads. The spherical objects might have formed in a water environment, the scientists have said before, but there could also be other explanations, including volcanism and meteor impacts.
The rovers have sent back a mountain of other data on rocks and soil that, as of late last week, had not been fully analyzed or in some cases had not yet been released.
The rovers landed in January and are schedule to explore Mars for at least three months. They could last into summer, however. The mission price tag is $820 million.
Here is an excerpt from a Google search pulled from NYT that deals with common de-icers available here on earth:
"Not all de-icers are created equal," said Edward Chouinard, president of Standard Tar Products, a company based in Milwaukee that makes Snomelt Instant Ice Melter. "But virtually all de-icers work on the same basic principle: They lower the freezing point of the water produced by the ice they melt."
Mr. Chouinard, whose company manufactures de-icing products used by homeowners, commercial property managers and state and local highway departments, explained that while plain water freezes at 32 degrees Fahrenheit, the freezing point of water containing a de-icing chemical is lower than that sometimes much lower.
"The nice thing about Snomelt is that it's exothermic," Mr. Chouinard said. "That means that when you mix it with water, it creates heat."
Some de-icers for example, sodium chloride, better known as halite or rock salt are endothermic, meaning that they need to absorb heat from the atmosphere, sunlight or friction from tires to melt ice or snow. As a result, while rock salt is the least expensive de-icing agent available selling for anywhere from $2.50 to $4 for a 50-pound bag it is only effective at temperatures above 15 or 20 degrees Fahrenheit.
Products like Snomelt, on the other hand, which is 90 to 95 percent calcium chloride and sells for about $15 for a 50-pound bag, can melt ice or snow at temperatures as low as minus 59 degrees Fahrenheit, depending on the concentration of the chemical in the solution produced by the melting ice a solution that de-icing experts call "brine."
In fact, it is the brine produced by a de-icing product rather than the melting action of the product itself that does the work the homeowner is hoping to avoid.
Rick May, marketing manager for Dow Chemical in Midland, Mich., said that most de-icing products work by penetrating the ice, dissolving into brine and then seeping into the pores of the concrete under the ice. Once there, the brine breaks the bond between the ice and the sidewalk, making it easier to remove the ice.
Mr. May added that while calcium chloride can indeed melt ice at minus 59 degrees Farenheit, that is the "laboratory limit" of the chemical's effectiveness. "In the real world, its practical effective temperature is more like minus 28 degrees Fahrenheit," he said, adding that the effective temperature of the chemical decreases because its concentration in the brine becomes lower as more and more ice melts.
When the rover makes a cup of tea from Martian water, I'll be a believer.
Alas, Spirit and Opportunity left the kettle behind...however, I shall be delighted to make you a cup of Lady Grey when we get there. :^)
A geologist here says they do not look like fossils. Scratch and Sniff are purely geology robots, unequipped to do organic testing. The ESA bot that crashed was equipped with some organic instruments. Sounds like later bots will have instruments more appropriate to analyze brine minerals.
Well I think they need at least one Paleontologist on the team. Squyres really comes across as an arrogant saganistic ass to me at least. I don't view him as an asset for NASA and he could have been more tactful with the one reporter who asked about the possible existence of surface water within the last couple of centuries. I find the non-mention of obvious biological indications disgusting. I also have no sympathy for Squyres should he bear later scorn and it would probably be better for me to reserve additional comments until a later date...
I can tell you this though, any bare foot ten year old who has ever picked up a gravel rock from a dirt road and seen the prehistoric indications of sea critters would look at these images returned by the rovers and say yea, those are fossils.
They'd better watch out. Next come the dart guns . . . then the thorazine shuffle with yer butt hanging out the back of a blue gown.
(That damn cat didn't need to take over the ping list AND throw in all that background context)
Well, I'd like to know how may of those "in-the-know" folks were skulking about with dour, unhappy faces after the "big" news release.
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