Scientists find evidence of recent water flows on Mars


Scientists analyzing data from a NASA spacecraft have found the first evidence that briny water flowed on the surface of Mars as recently as last summer, a paper published on Monday showed, raising the possibility that the planet could support life.

Although the source and the chemistry of the water is unknown, the discovery will change scientists' thinking about whether the planet that is most like Earth in the solar system could support present day microbial life.

“It suggests that it would be possible for life to be on Mars today,” John Grunsfeld, NASA's associate administration for science, told reporters.

“Mars is not the dry, arid planet that we thought of in the past. Under certain circumstances, liquid water has been found on Mars,” said Jim Green, the agency's director of planetary science.

The discovery was made when scientists developed a new technique to analyze chemical maps of the surface of Mars obtained by NASA's Mars Reconnaissance Orbiter spacecraft.

They found telltale fingerprints of salts that form only in the presence of water in narrow channels cut into cliff walls throughout the planet's equatorial region.

The slopes, first reported in 2011, appear during the warm summer months on Mars, then vanish when the temperatures drop. Scientists suspected the streaks, known as recurring slope lineae, or RSL, were cut by flowing water, but previously had been unable to make the measurements.

“I thought there was no hope,” Lujendra Ojha, a graduate student at Georgia Institute of Technology and lead author of a paper in this week's issue of the journal Nature Geoscience, told Reuters.

Mars Reconnaissance Orbiter makes its measurements during the hottest part of the Martian day, so scientists believed any traces of water, or fingerprints from hydrated minerals, would have evaporated.

Also, the chemical-sensing instrument on the orbiting spacecraft cannot home in on details as small as the narrow streaks, which typically are less than 16 feet (5 meters) wide.

But Ojha and colleagues created a computer program that could scrutinize individual pixels. That data was then correlated with high-resolution images of the streaks. Scientists concentrated on the widest streaks and came up with a 100 percent match between their locations and detections of hydrated salts.

The discovery “confirms that water is playing a role in these features,” said planetary scientist Alfred McEwen, with the University of Arizona. “We don't know that it's coming from the subsurface. It could come from the atmosphere.”

Whatever the water's source, the prospect of liquid water, even seasonally, raises the intriguing prospect that Mars, which is presumed to be a cold and dead planet, could support life today.

However, McEwen said much more information about the water's chemistry would be needed before scientists could make that assessment.

“It's not necessarily habitable just because it's water – at least to terrestrial organisms,” he said.

The evidence that there was water on the planet recently was the key finding in the study released on Monday. NASA's ongoing Mars rover Curiosity has already found evidence that Mars had all the ingredients and suitable habitats for microbial life to exist at some point in its past.

Scientists have been trying to figure out how it transformed from a warm, wet and likely Earth-like planet early in its history into the cold, dry desert that exists today.

Billions of years ago, Mars, which lacks a protective, global magnetic field, lost much of its atmosphere. Several initiatives are under way to determine how much of the planet's water was stripped away and how much remains locked in ice in underground reservoirs.

JPL prepares for ‘7 minutes of terror’


The atmosphere at Caltech’s Jet Propulsion Laboratory (JPL) will be a mixture of fear and anxiety on Sunday, Aug. 5, as its engineers and scientists hope to make history with the successful landing of the Curiosity rover on Mars.

The landing, described in the viral video, “7 Minutes of Terror,” is a risky descent into the Martian atmosphere that will require the lander to go from 13,000 mph to an almost dead stop in seven minutes—all without direct help from JPL.

“Sunday is the big day. The ‘7 Minutes of Terror’ video is not far off from how the landing will look. This really is the scariest part of the mission. However, we are all looking forward to it and [are] very excited,” said Richard Kornfeld, deputy lead for the mission’s entry, descent and landing (EDL) phase.

The Curiosity rover is NASA’s latest Mars Science Laboratory (MSL) mission, part of NASA’s Mars Exploration Program, a long-term effort devoted to the robotic exploration of Mars. Similar in design to past rovers Spirit and Opportunity, Curiosity is about twice as long and nearly five times as heavy — about the size of a Mini Cooper. At $2.5 billion, it’s the most expensive Mars mission to date.

Launched from Cape Canaveral on Nov. 26, 2011, Curiosity has traveled 352 million miles over more than 8 months. The rover’s mission is to determine whether conditions on Mars were once favorable for microbes.

The world will not know Curiosity’s fate until about 21 minutes after the rover first begins its landing at 10:31 p.m. PST. Once it enters Mars’ atmosphere, it will take seven minutes for the rover to land, but 14 minutes for the data to travel to Earth.

Following entry into the Martian atmosphere, which is 100 times thinner than Earth’s, the spacecraft will slow from 13,000 mph to 1,000 mph. With the release of a 100-pound supersonic parachute, the craft is expected to then drop its heat shield and slow to 200 mph. A descent stage, with the rover attached, will then separate and fire its rockets to navigate away from the spacecraft. Once hovering over Gale Crater, the descent stage will lower the rover via a sky-crane maneuver, cut its cords and then fly away.

A video camera on board Curiosity is expected to record several minutes of the landing.

[Story continues after the jump]

7 Minutes of Terror Video

“We are all going to be very nervous on Sunday, but also very optimistic. We’ve done every test we can imagine over the past years, but there are no guarantees. And, because landing on Mars doesn’t have a good track record, there will be a sense of nervousness in the air,” said Jonathan Grinblat, avionics subsystem Lead for cruise, approach and EDL operations.

Past mission failures are on the minds of JPL’s engineers.

In 1999, NASA lost its $125 million Mars Climate Orbiter when the craft entered too low of an orbit. An investigation traced the problem to a Lockheed Martin engineering team’s use of English units rather than standard metric units when writing part of the probe’s software.

Grinblat said that failed attempts helped with the Curiosity landing.

“The unsuccessful missions are definitely in the back of our minds. But we learned from those attempts what types of mistakes we can anticipate. It’s helping us to think outside of the box,” he said. “The hardest part is really trying to anticipate things we can’t even think of. We have to plan for the unknown. We have to make the rover robust enough to deal with things we can’t even imagine. And that’s the hardest part, being able to make the rover autonomously deal with the potential failure modes of landing on Mars and be able to recover.”

If successful, the rover will explore the planet for at least 687 Earth days (1 Martian year). During that time it will study the climate and geology of Mars, which will help NASA plan for a future manned mission to Mars.

“If everything goes well, it will be a pretty exciting science mission. On Monday morning, the science teams will take over and it switches to exploration and discovery mode,” said Robert Zimmerman, power systems engineer. “In terms of the future, it is hard to say what scientific data we are going to find and what we are going to be able to do with it. But one way or another, we learn a whole lot from this landing.”

Curiosity’s landing will be live-streamed on several Web sites and can be viewed on the NASA TV Media Channel. The Griffith Observatory will be hosting live coverage of the event with commentary and questions Sunday night from 9 p.m. to midnight.

To watch Curiosity’s landing, visit:
http://new.livestream.com/GriffithObservatoryTV/
http://www.ustream.tv/nasajpl2
http://www.nasa.gov/multimedia/nasatv/index.html
http://www.ustream.tv/nasajpl

Kids Page


The Red Valley

Have you seen the Red Planet lately? A few weeks ago, Mars came closer to Earth than it has in thousands of years. Usually, Mars is 50 million miles away. Although it is now receding, it is still about 34 million away. That means that it’s 16 million miles closer than it has been in thousands of years!

On Mars, there is a valley called Ma’adim Vallis. Scientists think it was created by water that gouged out a lake. The name for the valley was taken from the Hebrew word for Mars: Ma’adim, which comes from another Hebrew word, adom (red).

Mitzvah Makers

Please tell us, in no more than 50 words, about a mitzvah that you or someone else did that you think would make a great story and be a great example to others.

Send your essay, including a photo of the mitzvah-doer,
to The Jewish Journal, 3580 Wilshire Blvd., Suite 1510, Los Angeles, CA 90010.
If you do not have a photo, you can e-mail the essay to kids@jewishjournal.com . Deadline is Monday, Oct. 20, 2003.

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Seeing Stars

F.W. Herschel, a Jewish astronomer who lived from 1738 to 1822 is one of the six astronomers represented on the Astronomers Monument at The Griffith Observatory in Los Angeles. Herschel discovered the planet Uranus.

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