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Space News: NASA's Curiosity Rover finds patches of rock record erased, revealing clues – Lake County News

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A self-portrait of NASA’s Curiosity rover taken on June 15, 2018, during the 2,082nd Martian day, or sol, of Curiosity’s work on Mars. A Martian dust storm has reduced sunlight and visibility at the rover’s location in Gale Crater. Image credit: NASA/JPL-Caltech.

Today, Mars is a planet of extremes — it’s bitterly cold, has high radiation, and is bone-dry.

But billions of years ago, Mars was home to lake systems that could have sustained microbial life. As the planet’s climate changed, one such lake — in Mars’ Gale Crater — slowly dried out.

Scientists have new evidence that super salty water, or brines, seeped deep through the cracks, between grains of soil in the parched lake bottom and altered the clay mineral-rich layers beneath.

The findings published in the July 9 edition of the journal Science and led by the team in charge of the Chemistry and Mineralogy, or CheMin, instrument — aboard NASA’s Mars Science Laboratory Curiosity rover — help add to the understanding of where the rock record preserved or destroyed evidence of Mars’ past and possible signs of ancient life.

“We used to think that once these layers of clay minerals formed at the bottom of the lake in Gale Crater, they stayed that way, preserving the moment in time they formed for billions of years,” said Tom Bristow, CheMin principal investigator and lead author of the paper at NASA’s Ames Research Center in California’s Silicon Valley. “But later brines broke down these clay minerals in some places – essentially re-setting the rock record.”

The network of cracks in this Martian rock slab called “Old Soaker” may have formed from the drying of a mud layer more than three billion years ago. The view spans about three feet (90 centimeters) left-to-right and combines three images taken by the Mars Hand Lens Imager, or MAHLI, camera on the arm of NASA’s Curiosity Mars rover. Credits: NASA/JPL-Caltech/MSSS.

Mars: It goes on your permanent record

Mars has a treasure trove of incredibly ancient rocks and minerals compared with Earth. And with Gale Crater’s undisturbed layers of rocks, scientists knew it would be an excellent site to search for evidence of the planet’s history, and possibly life.

Using CheMin, scientists compared samples taken from two areas about a quarter-mile apart from a layer of mudstone deposited billions of years ago at the bottom of the lake at Gale Crater.

Surprisingly, in one area, about half the clay minerals they expected to find were missing. Instead, they found mudstones rich with iron oxides — minerals that give Mars its characteristic rusty red color.

Scientists knew the mudstones sampled were about the same age and started out the same – loaded with clays — in both areas studied.

So why then, as Curiosity explored the sedimentary clay deposits along Gale Crater did patches of clay minerals — and the evidence they preserve — “disappear”?

This evenly layered rock imaged in 2014 by the Mastcam on NASA’s Curiosity Mars rover shows a pattern typical of a lake-floor sedimentary deposit near where flowing water entered a lake. Shallow and deep parts of an ancient Martian lake left different clues in mudstone formed from lakebed deposits. Credits: NASA/JPL-Caltech/MSSS.

Clays hold clues

Minerals are like a time capsule; they provide a record of what the environment was like at the time they formed. Clay minerals have water in their structure and are evidence that the soils and rocks that contain them came into contact with water at some point.

“Since the minerals we find on Mars also form in some locations on Earth, we can use what we know about how they form on Earth to tell us about how salty or acidic the waters on ancient Mars were,” said Liz Rampe, CheMin deputy principal investigator and co-author at NASA’s Johnson Space Center in Houston.

Previous work revealed that, while Gale Crater’s lakes were present and even after they dried out, groundwater moved below the surface, dissolving and transporting chemicals.

After they were deposited and buried, some mudstone pockets experienced different conditions and processes due to interactions with these waters that changed the mineralogy.

This process, known as “diagenesis,” often complicates or erases the soil’s previous history and writes a new one.

Diagenesis creates an underground environment that can support microbial life. In fact, some very unique habitats on Earth — in which microbes thrive — are known as “deep biospheres.”

“These are excellent places to look for evidence of ancient life and gauge habitability,” said John Grotzinger, CheMin co-investigator and co-author at Caltech in Pasadena, California. “Even though diagenesis may erase the signs of life in the original lake, it creates the chemical gradients necessary to support subsurface life, so we are really excited to have discovered this.”

By comparing the details of minerals from both samples, the team concluded that briny water filtering down through overlying sediment layers was responsible for the changes. Unlike the relatively freshwater lake present when the mudstones formed, the salty water is suspected to have come from later lakes that existed within an overall drier environment.

Scientists believe these results offer further evidence of the impacts of Mars’s climate change billions of years ago. They also provide more detailed information that is then used to guide the Curiosity rover’s investigations into the history of the Red Planet.

This information also will be utilized by NASA’s Mars 2020 Perseverance rover team as they evaluate and select rock samples for eventual return to Earth.

“We’ve learned something very important: there are some parts of the Martian rock record that aren’t so good at preserving evidence of the planet’s past and possible life,” said Ashwin Vasavada, Curiosity project scientist and co-author at NASA’s Jet Propulsion Laboratory in Southern California. “The fortunate thing is we find both close together in Gale Crater, and can use mineralogy to tell which is which.”

Curiosity is in the initial phase of investigating the transition to a “sulfate-bearing unit,” or rocks thought to have formed while Mars’s climate dried out.

The mission is managed by JPL, a division of Caltech, for NASA’s Science Mission Directorate, Washington. Colleagues in NASA’s Astromaterials Research and Exploration Science Division at Johnson and NASA’s Goddard Space Flight Center in Greenbelt, Maryland also are authors on the paper, as well as other institutions working on Curiosity.

This Martian landscape includes the rocky landmark nicknamed “Knockfarril Hill” at center right and the edge of Vera Rubin Ridge, which runs along the top of the scene. The image was made from a mosaic captured by the Mast Camera aboard NASA’s Curiosity Mars rover as it explored the “clay-bearing unit” on Feb. 3, 2019, during the 2,309th Martian day, or sol, of Curiosity’s work on Mars. Credits: NASA/JPL-Caltech/MSSS.

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NASA discovers double crater on the moon – CTV News

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The moon has a new double crater after a rocket body collided with its surface on March 4.

New images shared by NASA’s Lunar Reconnaissance Orbiter, which has been circling the moon since 2009, have revealed the location of the unusual crater.

The impact created two craters that overlap, an eastern crater measuring 59 feet (18 metres) across and a western crater spanning 52.5 feet (16 metres). Together, they create a depression that is roughly 91.8 feet (28 metres) wide in the longest dimension.

Although astronomers expected the impact after discovering that the rocket part was on track to collide with the moon, the double crater it created was a surprise.

Typically, spent rockets have the most mass at the motor end because the rest of the rocket is largely just an empty fuel tank. But the double crater suggests that this object had large masses at both ends when it hit the moon.

The exact origin of the rocket body, a piece of space junk that had been careening around for years, is unclear, so the double crater could help astronomers determine what it was.

The moon lacks a protective atmosphere, so it’s littered with craters created when objects like asteroids regularly slam into the surface.

This was the first time a piece of space junk unintentionally hit the lunar surface that experts know of. But craters have resulted from spacecraft being deliberately crashed into the moon.

For example, four large moon craters attributed to the Apollo 13, 14, 15 and 17 missions are all much larger than each of the overlapping craters created during the March 4 impact. However, the maximum width of the new double crater is similar to the Apollo craters.

UNCLEAR ORIGIN

Bill Gray, an independent researcher focused on orbital dynamics and the developer of astronomical software, was first to spot the trajectory of the rocket booster.

Gray had initially identified it as the SpaceX Falcon rocket stage that launched the US Deep Space Climate Observatory, or DSCOVR, in 2015 but later said he’d gotten that wrong and it was likely from a 2014 Chinese lunar mission — an assessment NASA agreed with.

However, China’s Ministry of Foreign Affairs denied the booster was from its Chang’e-5 moon mission, saying that the rocket in question burned up on reentry to Earth’s atmosphere.

No agencies systematically track space debris so far away from Earth, and the confusion over the origin of the rocket stage has underscored the need for official agencies to monitor deep-space junk more closely, rather than relying on the limited resources of private individuals and academics.

However, experts say that the bigger challenge is the space debris in low-Earth orbit, an area where it can collide with functioning satellites, create more junk and threaten human life on crewed spacecraft.

There are at least 26,000 pieces of space junk orbiting Earth that are the size of a softball or larger and could destroy a satellite on impact; over 500,000 objects the size of a marble — big enough to cause damage to spacecraft or satellites; and over 100 million pieces the size of a grain of salt, tiny debris that could nonetheless puncture a spacesuit, according to a NASA report issued last year.

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7 Amazing Dark Sky National Parks – AARP

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James Ronan/Getty Images/Steve Burns

Great Basin, Arches, and Voyageurs National Park

Can’t afford to join a commercial space mission offered by Jeff Bezos or Richard Branson? Consider the next best thing: seeing a starry, starry night in a sea of darkness, unimpeded by artificial light, at one of the International Dark Sky Parks in the U.S. It’s a rare treat, since light pollution prevents nearly 80 percent of Americans from seeing the Milky Way from their homes.

The International Dark-Sky Association (IDSA) has certified 14 of the nation’s 63 national parks as dark sky destinations. So visitors can take full advantage of such visibility, many of them offer specialized after-dark programs, from astronomy festivals and ranger-led full-moon walks to star parties and astrophotography workshops. If you prefer to stargaze on your own at a park, the National Park Service recommends bringing a pair of 7-by-50 binoculars, a red flashlight, which enhances night vision, and a star chart, which shows the arrangement of stars in the sky.

Here are seven of the IDSA-certified parks where you can appreciate how the heavens looked from the Earth before the dawn of electric light.




AARP Membership -Join AARP for just $9 per year when you sign up for a 5-year term

Join today and save 43% off the standard annual rate. Get instant access to discounts, programs, services, and the information you need to benefit every area of your life. 



Award-winning travel writer Veronica Stoddart is the former travel editor of USA Today. She has written for dozens of travel publications and websites.​​

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A Mystery Rocket Left A Crater On The Moon – Forbes

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While we think of the moon as a static place, sometimes an event happens that reminds us that things can change quickly.

On March 4, a human-made object (a rocket stage) slammed into the moon and left behind a double crater, as seen by NASA’s Lunar Reconnaissance Orbiter (LRO) mission.

Officials announced June 23 that they spotted a double crater associated with the event. But what’s really interesting is there’s no consensus about what kind of rocket caused it.

China has denied claims that the rocket was part of a Long March 3 rocket that launched the country’s Chang’e-5 T1 mission in October 2014, although the orbit appeared to match. Previous speculation suggested it might be from a SpaceX rocket launching the DISCOVR mission, but newer analysis has mostly discredited that.

On a broader scale, the value of LRO observations like this is showing how the moon can change even over a small span of time. The spacecraft has been in orbit there since 2009 and has spotted numerous new craters since its arrival.

It’s also a great spacecraft scout, having hunted down the Apollo landing sites from orbit and also having tracked down a few craters from other missions that slammed into the moon since the dawn of space exploration.

It may be that humans return to the moon for a closer-up look in the coming decade, as NASA is developing an Artemis program to send people to the surface no earlier than 2025.

LRO will also be a valuable scout for that set of missions, as the spacecraft’s maps will be used to develop plans for lunar bases or to help scout safe landing sites for astronauts.

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