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Brain-eating amoeba rattles nerves in Louisiana after being found in local water.NEW ORLEANS (AP) — A deadly, brain- eating amoeba has been...
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The roving laboratory performed extensive tests to search for traces of Martian methane. Whether the Martian atmosphere contains traces of t...
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On September 26, 1973, the Concorde supersonic airliner flew from Washington D.C. to Paris for the first time, in a record-breaking 3 hours ...
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A robot that feels, sees and, in particular, thinks an d learns like us. It still seems like science fiction, but if it's up to Univers...
Monday, September 23, 2013
NASA Curiosity Rover Detects No Methane On Mars.
The roving laboratory performed extensive
tests to search for traces of Martian methane.
Whether the Martian atmosphere contains
traces of the gas has been a question of high
interest for years because methane could be a
potential sign of life, although it also can be
produced without biology.
"This important result will help direct our
efforts to examine the possibility of life on
Mars," said Michael Meyer, NASA's lead
scientist for Mars exploration. "It reduces the
probability of current methane-producing
Martian microbes, but this addresses only one
type of microbial metabolism. As we know,
there are many types of terrestrial microbes
that don't generate methane."
Curiosity analyzed samples of the Martian
atmosphere for methane six times from
October 2012 through June and detected none.
Given the sensitivity of the instrument used,
the Tunable Laser Spectrometer, and not
detecting the gas, scientists calculate the
amount of methane in the Martian atmosphere
today must be no more than 1.3 parts per
billion. That is about one-sixth as much as
some earlier estimates. Details of the findings
appear in the Thursday edition of Science
Express.
"It would have been exciting to find methane,
but we have high confidence in our
measurements, and the progress in expanding
knowledge is what's really important," said the
report's lead author, Chris Webster of NASA's
Jet Propulsion Laboratory in Pasadena, Calif.
"We measured repeatedly from Martian spring
to late summer, but with no detection of
methane."
Webster is the lead scientist for spectrometer,
which is part of Curiosity's Sample Analysis at
Mars (SAM) laboratory. It can be tuned
specifically for detection of trace methane. The
laboratory also can concentrate any methane
to increase the gas' ability to be detected. The
rover team will use this method to check for
methane at concentrations well below 1 part
per billion.
Methane, the most abundant hydrocarbon in
our solar system, has one carbon atom bound
to four hydrogen atoms in each molecule.
Previous reports of localized methane
concentrations up to 45 parts per billion on
Mars, which sparked interest in the possibility
of a biological source on Mars, were based on
observations from Earth and from orbit around
Mars. However, the measurements from
Curiosity are not consistent with such
concentrations, even if the methane had
dispersed globally.
"There's no known way for methane to
disappear quickly from the atmosphere," said
one of the paper's co-authors, Sushil Atreya of
the University of Michigan, Ann Arbor.
"Methane is persistent. It would last for
hundreds of years in the Martian atmosphere.
Without a way to take it out of the atmosphere
quicker, our measurements indicate there
cannot be much methane being put into the
atmosphere by any mechanism, whether
biology, geology, or by ultraviolet degradation
of organics delivered by the fall of meteorites
or interplanetary dust particles."
The highest concentration of methane that
could be present without being detected by
Curiosity's measurements so far would amount
to no more than 10 to 20 tons per year of
methane entering the Martian atmosphere,
Atreya estimated. That is about 50 million
times less than the rate of methane entering
Earth's atmosphere.
Curiosity landed inside Gale Crater on Mars in
August 2012 and is investigating evidence
about habitable environments there. JPL
manages the mission and built the rover for
NASA's Science Mission Directorate in
Washington. The rover's Sample Analysis at
Mars suite of instruments was developed at
NASA's Goddard Space Flight Center in
Greenbelt, Md., with instrument contributions
from Goddard, JPL and the University of Paris
in France.
Brain Eatting Amoeba.
Brain-eating amoeba rattles nerves in
Louisiana after being found in local water.NEW ORLEANS (AP) — A deadly, brain-
eating amoeba has been found in the water
supply of a Louisiana community near New
Orleans, scaring residents and sending
officials on the hunt for its source.
Experts say the only danger is to people
who manage to get the microscopic
organism way up their noses. Its only entry
to the brain is through tiny openings in a
bone about level with the top of the eyeball,
said Dr. Raoult Ratard, Louisiana's state
epidemiologist.
The state Department of Health and
Hospitals on Thursday tried to dispel
common "myths and rumors" about the
amoeba Naegleria fowleri — starting with
the notion that the St. Bernard Parish water
isn't safe to drink.
The worries began Sept. 12, when the state
health department reported that water in
the Violet and Arabi communities outside
New Orleans tested positive for the amoeba
that killed a 4-year-old Mississippi boy in
August after he visited St. Bernard Parish.
Jonathan Yoder, an epidemiologist in the
Center for Disease Control and Prevention's
waterborne disease prevention branch, said
Naegleria has never before been found in
water treated by a U.S. water system.
There have been 132 documented infections
from the amoeba since 1962, almost all of
them fatal, health officials say.
Both of Louisiana's 2011 infections were of
people who used tap water to flush out their
sinuses. In those cases, Yoder said the
amoeba was found in the house's hot water
system but not in municipal water or water
coming from the home's cold water tap.
But still, people worry.
"Nobody's washing their faces in the
showers anymore. Nobody's drinking the
water," Angela Miller said Thursday. "My
neighbor has a pool that they have emptied.
And they have no water in there now until
this matter is cleared up."
That's not necessary, experts say. Stomach
acids, boiling and chlorine all will kill the
amoeba.
Investigators may never know just how
Naegleria got into the pipes.
Copyright (2013) Associated Press. All rights
reserved. This material may not be
published, broadcast, rewritten, or
redistributed.
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