In today's edition, we have 3 stories about water.
- Water Bears Triumph Over Outer Space
- On an Infested River, Battling Invaders Eye to Eye
- An Icy Discovery on Mars, but Where’s the Water?
Water Bears Triumph Over Outer Space
For as long as humans have dreamed about spaceflight, they have also had nightmares about the perils of space. There’s the cold vacuum, of course, which can freeze-dry an unprotected astronaut. There are other hazards, too, including the sun’s ultraviolet rays, unfiltered by atmosphere.
Too bad we all can’t be tardigrades, those tiny roly-poly invertebrates that live in lakes and oceans and among mosses and lichens. European researchers report that these creatures, commonly called water bears, can survive in space.
K. Ingemar Jonsson of Kristianstad University in Sweden and colleagues shipped two species of tardigrades aboard a 2007 European Space Agency mission that reached low-Earth orbit, about 160 miles up. Some of the water bears were exposed to the vacuum of space only, while others were exposed to vacuum and ultraviolet radiation.
As the researchers describe in Current Biology, the tardigrades survived vacuum-only conditions well. This is perhaps not surprising, because water bears are able to deal with extreme dehydration. In fact, the specimens used in the experiment were already desiccated, and upon re-entry they were rehydrated and revived.
But even a few of the specimens exposed to the full spectrum and intensity of ultraviolet radiation — about 1,000 times as intense as that on Earth — survived. Thus the water bears join some lichens and bacteria as the only species known to be able to cope, unprotected, with both the vacuum and solar radiation in space. source
My comment: Check out the lovely creature on this lovely site . Here's little info:
Water Bears are tiny animals you need a microscope to see. They live in mosses, lichens, and liverworts. A few species live on plants in fresh water.
The mouths of Water Bears have sharp pointy objects, called stylets. They use their stylets to cut into moss leaves or algae, their main foods. Then they suck the juices from the plant.
Water Bears sometimes eat tiny animals called nematodes and rotifers that also live in moss.
Water Bears have developed an interesting way to survive if the moss they live in dries up. It is called an "antibiotic state." Since they need moisture to live, if a moss dries up, the Water Bear becomes inactive, almost like a hibernation. It mostly dries up also. Then, when the moss becomes wet again, so does the Water Bear. It revives, and goes on with its life. Sometimes, Water Bears can be in an antiobiotic state for several years.
Aren't they simply adorable? Well, they are to me. And if you think about them, there can as easily be absolutely alien to Earth. I mean, they look weird for sure, they can survive space for years and when they reach water, they just revive. And water isn't that exquisite to Earth as people think even if some people try very hard to convince us, it is. This little animal definitely gets my vote for an alien.
On an Infested River, Battling Invaders Eye to Eye
With their open boat skipping like a silvery stone along the Illinois River, the fish experts scan the mocha waters for what they call “incoming.” Bodies hunched in anticipation, they look left and right, front and behind; you never know, they say.
“If you put your guard down, you could easily get seriously injured,” says Kevin Irons, one of the researchers, who once got hit in the head. A colleague, Matt O’Hara, nods in empathy from behind the mesh netting that protects the boat’s driver from being knocked unconscious.
“I got hit in the back once,” he says. “It left an imprint of a fish.”
Until their boat slows down, that is, and fish by the dozens, some weighing 10 pounds or more, explode out of the water as though shot from the cannons of an underwater armada.
The agitated fish, who perceive the boat as a predator, rocket like slimy torpedoes through the air, against the hull of the boat, into the netting, onto the floor. The correspondent takes one in the leg and the photographer takes one in the midsection, but both fare better than the college biology major who had her lip split last week.
Though awesome and even unnerving to behold, the fishy fusillade is all too common on the Illinois River — and it is not good. These are Asian carp, a ravenous, rapidly multiplying invasive species that in the last decade has threatened the well-being of native fish, affected commercial fishing and transformed the typical workday for these researchers into a scene from “Apocalypse Now.”
To prevent this nightmare from becoming reality, the Army Corps of Engineers is expanding an underwater electrical barrier it built a few years ago in Romeoville, about 170 miles northeast of here. The system, whose projected total cost is $36.5 million, emits electrical currents to dissuade the carp — and all other fish — from making their way to the lake. The project’s name conveys its gravity: the Chicago Sanitary and Ship Canal Aquatic Nuisance Species Dispersal Barrier.
The back story to the invasion of the Asian carp reads like a horror-movie script. In the early 1970s, bighead carp and silver carp were imported from China and eastern Siberia to eat the algae clotting fish farms in the South. But a series of floods over the years helped them to escape their controlled environment. Cue the “Jaws” theme.
Today this 80-mile stretch of the Illinois River may have the largest population of Asian carp in the world, said Greg Sass, the field station’s director. “There’s been an exponential increase in their numbers and biomass,” he said. It’s out of control.
Now the researchers are cutting fast again through the murky waters in an aluminum “shock” boat, which has equipment that can electrify the water, paralyzing fish long enough for the researchers to scoop them up and identify and measure them before tossing them back.
In 2006, the researchers caught around 500 silver carp. In 2007, around 10,000. So far this year, with only two-thirds of the sampling complete, they have caught nearly 80,000 silver carp that now compete in an eating contest with native fish for the river’s algae and zooplankton. The carp often win.
This explains why the shock boat has been customized to ward off carp attacks that have bruised bodies and damaged equipment, including one brand-new depth finder. It has wings around the sides to “block the fish,” Mr. Irons says, and netting fused to an aluminum frame to protect the driver.
After 15 minutes of stunning and scooping, the researchers begin to count and record. White bass. Black crappie. Bigmouth buffalo. Common carp. Silver carp. Silver carp. Silver carp.
Someday, perhaps, someone will develop a lemonade-from-lemons plan for these fish — a commercially viable way to use them as fertilizer, or to export them to China and other countries, where they are a common food source. Mr. Irons says, by the way, that the carp are surprisingly tasty.source
I mean, seriously, those fishes are scary. I don't know why they let them multiply in such numbers and didn't think of fighting them earlier. Or at least to fish them and eat them. Or export them to Africa for free. So much of the capitalist economics. But it's a good evidence of the way nature work and species adapt to new environment. Everyone think Global Warming and our irresponsible actions are about damaging the Earth. Well, check out this, it's not about Earth, it's about us, the Earth has plenty of ways to survive and to make the best out of every bad situation. But we don't and our market-based life is very fragile to sudden and dramatic changes. So, we're the one that will suffer, not Nature. Nature is way bigger than that and has seen bigger problems than humans.
An Icy Discovery on Mars, but Where’s the Water?
A few years ago, the Mars Odyssey spacecraft found, from orbit, signs of vast quantities of water ice a few inches below the planet’s surface. In July, mission scientists confirmed that patches of white seen in the soil near the lander were indeed ice.
Phoenix’s weather station has also detected wisps of water vapor in the thin Martian air, and scientists expected that as the nighttime temperature plunged to minus-110 degrees Fahrenheit from minus-20 — and with it the amount of moisture that the Martian air can hold — minuscule specks of moisture would glom onto dust particles at the surface. The presence of water would show up in electrical measurements by a probe stuck into the soil. Except Mars has not cooperated.
“We’re seeing nothing,” said Aaron Zent of the NASA Ames Research Center at Moffett Field, Calif., the lead scientist for Phoenix’s thermal and electroconductivity probe.
Actually, the first measurement did yield the expected readings. “A lovely signal,” Dr. Zent said. “But we never saw it again.” Every subsequent measurement, taken at almost all hours of the day, indicated dry soil.
On Earth, dropping moisture level in the air leads to the condensation of morning dew; on Mars, because the water layer on the dust particles would be only a couple of molecules thick, it would not freeze into the crystal structure of ice, but instead remain more liquidlike, with molecules able to move along the surface of the grains.
The moisture in the air during the day has to go somewhere at night, and that somewhere seems almost certain to be the soil. “It has to,” Dr. Zent said. “There’s no other place for it to go. The soil is sucking it up at night. We certainly expect that we should be able to see some of this.”
Dr. Zent said that perhaps the signal was more subtle than expected. It is possible that the water layer is somehow thick enough to freeze into ice, which would not show the expected electrical behavior. (Photographs of the landscape do show frost on the ground in the morning.) Or the water layer is so thin that the molecules bind tightly to the dirt; that, too, would suppress the electrical signal.
The next step is for Phoenix to jam its electroconductivity probe deeper into the soil, closer to the ice layer. Maybe then, Phoenix will once again discover water. source
My comment: Ok, I have two comments. First, as we know nature doesn't like controversies so if you don't see something, it's either not there or you're not well-enough equipped to see it. So, if they are not seeing what they expected, they should find out why, not explain on medias that there is nothing and they are so overwhelmed by this. It's not very scientific and I think it's bad publicity for science. It's like they are searching for compassion that they screwed up. Come on, people, we know better than that. Especially since it doesn't mean there is no water, it means it doesn't condense at night the way you thought it would. And as the sentence in bold shows, there are explanation for that. I'm sick of those populism that is ruling in USA. I mean, seriously, why do you have to search for compassion, you're a professionalist, if something goes wrong, you make do with it and give facts, not appologies.
My second comment is about that signal they got and then disappeared. Signals don't just do that. If they do it, there have to be reason. Either the apparature broke down, or conditions changed or someone from either Earth or Mars is jamming the signal. Well, how about looking at this possibilities, not explaining how you looked on and on and the signal wasn't there. IF the conditions didin't change, then it's one of the other possibilities. The only other option is that you have a psychic in the mission. And s/he's messing with the resutls. Come on, get real! This is a science, you should be rational...