Wednesday, May 18, 2011

Is the Rocky Alien Planet Gliese 581d Really Habitable?

Gliese 581dA rocky alien planet called Gliese 581d may be the first known world beyond Earth capable of supporting life as we know it, a new study suggests.

Astronomers performing a new atmospheric-modeling study have found that the planet likely lies in the "habitable zone" of its host star — that just-right range of distances that allow liquid water to exist. The alien world could be Earth-like in key ways, harboring oceans, clouds and rainfall, according to the research.

This conclusion is consistent with several other recent modeling studies. But it does not definitively establish that life-sustaining water flows across the planet's surface.
The new study assumes that Gliese 581d, which is about seven times as massive as Earth, has a thick, carbon-dioxide-based atmosphere. That's very possible on a planet so large, researchers said, but it's not a given.

The Gliese 581 system: Worlds of possibilities:

Gliese 581d's parent star, known as Gliese 581, is a red dwarf located 20 light-years from Earth, just a stone's throw in the cosmic scheme of things. So far, astronomers have detected six planets orbiting the star, and Gliese 581d is not the only one intriguing to scientists thinking about the possibility of life beyond Earth.

Another planet in the system, called Gliese 581g, is about three times as massive as Earth, and it's also most likely a rocky world. This planet received a lot of attention when its discovery was announced in September 2010, because it's located right in the middle of the habitable zone. That makes 581g a prime candidate for liquid water and life as we know it — if the planet exists.

Some researchers question the analysis used to discover the planet, and say they cannot confirm 581g in follow-up studies. The planet's discoverers, however, are standing by their find.

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Sunday, May 8, 2011

Moon Microbe Mystery Finally Solved


There has been a long-lived bit of Apollo moon landing folklore that now appears to be a dead-end affair: microbes on the moon.

The lunar mystery swirls around the Apollo 12 moon landing and the return to Earth by moonwalkers of a camera that was part of an early NASA robotic lander – the Surveyor 3 probe.


On Nov. 19, 1969, Apollo 12 astronauts Pete Conrad and Alan Bean made a precision landing on the lunar surface in Oceanus Procellarum, Latin for the Ocean of Storms. Their touchdown point was a mere 535 feet (163 meters) from the Surveyor 3 lander -- and an easy stroll to the hardware that had soft-landed on the lunar terrain years before, on April 20, 1967.


The Surveyor 3 camera was easy pickings and brought back to Earth under sterile conditions by the Apollo 12 crew. When scientists analyzed the parts in a clean room, they found evidence of microorganisms inside the camera.


In short, a small colony of common bacteria -- Streptococcus Mitis -- had stowed away on the device.

The astrobiological upshot as deduced from the unplanned experiment was that 50 to 100 of the microbes appeared to have survived launch, the harsh vacuum of space, three years of exposure to the moon's radiation environment, the lunar deep-freeze at an average temperature of minus 253 degrees Celsius, not to mention no access to nutrients, water or an energy source.


Now, fast forward to today.


NASA's dirty little secret?


A diligent team of researchers is now digging back into historical documents -- and even located and reviewed NASA's archived Apollo-era 16 millimeter film -- to come clean on the story.

As it turns out, there's a dirty little secret that has come to light about clean room etiquette at the time the Surveyor 3 camera was scrutinized.


"The claim that a microbe survived 2.5 years on the moon was flimsy, at best, even by the standards of the time," said John Rummel, chairman of the Committee on Space Research (COSPAR) Panel on Planetary Protection. "The claim never passed peer review, yet has persisted in the press -- and on the Internet -- ever since."

The Surveyor 3 camera-team thought they had detected a microbe that had lived on the moon for all those years, "but they only detected their own contamination," Rummel told SPACE.com.


A former NASA planetary protection officer, Rummel is now with the Institute for Coastal Science & Policy at East Carolina University in Greenville, N.C.


Rummel, along with colleaguesJudith Allton of NASA’s Johnson Space Center and Don Morrison, a former space agency lunar receiving laboratory scientist, recently presented their co-authored paper: "A Microbe on the Moon? Surveyor III and Lessons Learned for Future Sample Return Missions."


Poor space probe hygiene


Their verdict was given at a meeting on "The Importance of Solar System Sample Return Missions to the Future of Planetary Science," in March at The Woodlands,Texas, sponsored by the NASA Planetary Science Division and Lunar and Planetary Institute.

"If 'American Idol' judged microbiology, those guys would have been out in an early round," the research team writes of the way the Surveyor 3 camera team studied the equipment here on Earth. Or put more delicately, "The general scene does not lend a lot of confidence in the proposition that contamination did not occur," co-author Morrison said.


For example, participants studying the camera were found to be wearing short-sleeve scrubs, thus arms were exposed. Also, the scrub shirt tails were higher than the flow bench level … and would act as a bellows for particulates from inside the shirt, reports co-author Allton.


Other contamination control issues were flagged by the researchers.


In simple microbiology 101 speak, "a close personal relationship with the subject ... is not necessarily a good thing," the research team explains.


All in all, the likelihood that contamination occurred during sampling of the Surveyor 3 camera was shown to be very real.


A cautionary tale


On one hand, Rummel emphasized that today’s methods for handling return samples are much more effective at detecting microbes.


However, the Surveyor 3 incident back then raises a cautionary flag for the future.

"We need to be orders of magnitude more careful about contamination control than was the Surveyor 3 camera-team. If we aren't, samples from Mars could be drowned in Earth life upon return, and in all of that 'noise' we might never have the ability to detect Mars life we may have brought back, too," Rummel said. "We can, and we must, do a better job with a Mars sample return mission."

Winner of this year's National Space Club Press Award, Leonard David has been reporting on the space industry for more than five decades. He is past editor-in-chief of the National Space Society's Ad Astra and Space World magazines and has written for SPACE.com since 1999.


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Thursday, May 5, 2011

Horoscope overview for May


Aries: You rupture with life force and at mid-month, find ways to match your impulses with praiseworthy, big-enough goals.

Taurus: A big month for Love and a sugary taste of what's to come with Jupiter in your sign starting June 4th.

Gemini: A month of rooting in.Yourself.

Cancer: Extra contented moments, less worry/fear.

Leo: This month to look for what's deeply satisfying in love and life, and to nurture your ambitions.

Virgo: This month to join your energies, toward inspired, self-centered goals.

Libra: Trusting your first impressions leads you to an edgier, natural way of being.

Scorpio: Come away from the extremes, and stay into a deep groove of productivity, sensuality, calm.
Sagittarius: A sensational month, when you keep a touch of sensibility.

Capricorn: This month for happiness, a love supreme day in earthy Taurus (May 23rd) and extra.

Aquarius: This month to strut yourself for deepening pleasure, sense of life purpose.

Pisces: Spend time with your ponder, and exit the fear matrix -- very creative month for you!