News from Mars: Laser-Blasting and Soil Sampling

mars_lifeAs the exploration of Mars goes on, the small army of robotic rovers, satellites and orbiters continue to provide us with information, photographs and discoveries that remind us of how great a mystery the Red Planet truly is. For instance, in the past month, two major stories have been announced concerning the nature of Martian soil, its ancient history, and some of the more exciting moments in it’s exploration.

For example, Curiosity made news as its high resolution camera caught an image of sparks being generated as it zapped a Martian rock. In it’s lifetime, the rover has used its million watt Chemistry and Camera (ChemCam) laser to zap over 600 rock or soil targets as part of its mission. However, this was the first time that the rover team was able to get the arm-mounted Mars Hand Lens Imager (MAHLI) to capture the action as it occurred.

Curiosity-Laser-BeamThe ChemCam laser is used to determine the composition of Martian rocks and soils at a distance of up to 8 meters (25 feet). By hitting targets with several high-energy pulses, it is able to yield preliminary data for the scientists and engineers back at Earth to help them decide if a target warrants a closer investigation and, in rare cases, sampling and drilling activities.

ChemCam works through a process called laser-induced breakdown spectroscopy. The laser hits a target with pulses to generate sparks, whose spectra provide information about which chemical elements are in the target. Successive laser shots are fired in sequence to gradually blast away thin layers of material. Each shot exposes a slightly deeper layer for examination by the ChemCam spectrometer.

Mars_novarockAs Curiosity fired deeper into the target rock – named “Nova” – it showed an increasing concentration of aluminum as the sequential laser blasts penetrated through the uninteresting dust on the rock’s surface. Silicon and sodium were also detected. As Sylvestre Maurice, ChemCam’s Deputy Principal Investigator at the Research Institute in Astrophysics and Planetology, said in a statement:

This is so exciting! The ChemCam laser has fired more than 150,000 times on Mars, but this is the first time we see the plasma plume that is created… Each time the laser hits a target, the plasma light is caught and analyzed by ChemCam’s spectrometers. What the new images add is confirmation that the size and shape of the spark are what we anticipated under Martian conditions.

During it’s first year on Mars, Curiosity has already accomplished its primary objective of discovering a habitable zone on Mars that contains the minerals necessary to support microbial life billions of years ago when Mars was wetter and warmer. Currently, the rover is driving swiftly to the base of Mount Sharp at the center of Gale Crater, where it hopes to find more.

Mars_soilIn that same vein, according to new geological information obtained by Curiosty’s images and soil examinations, samples that were pulled out of a crater that is estimated to be some 3.7 billion years old contain more evidence that Mars was once much warmer and wetter. These findings were announced in a recent paper published in the online edition of Geology by University of Oregon geologist Gregory Retallack.

Unlike Earth, the Martian landscape is littered with loose rocks from impacts or layered by catastrophic floods. However, recent images from Curiosity from the Gale Crater reveal Earth-like soil profiles with cracked surfaces lined with sulfate, ellipsoidal hollows and concentrations of sulfate comparable with soils in Antarctica’s McMurdo Dry Valleys and Chile’s Atacama Desert.

mars-180-degrees-panorama_croppedRetallack, the paper’s lone author, studied mineral and chemical data published by researchers closely tied with the Curiosity mission. As a professor of geological sciences and co-director of paleontology research at the UO Museum of Natural and Cultural History, he internationally known as an expert on the recognition of paleosols – ancient fossilized soils contained in rocks.

As he explains in the paper:

The pictures were the first clue, but then all the data really nailed it. The key to this discovery has been the superb chemical and mineral analytical capability of the Curiosity Rover, which is an order of magnitude improvement over earlier generations of rovers. The new data show clear chemical weathering trends, and clay accumulation at the expense of the mineral olivine, as expected in soils on Earth. Phosphorus depletion within the profiles is especially tantalizing, because it attributed to microbial activity on Earth.

dryvalleysThe ancient soils do not prove that Mars once contained life, but they do add to growing evidence that an early, wetter and warmer Mars was more habitable than the planet has been in the past 3 billion years. Surface cracks in the deeply buried soils suggest typical soil clods. Vesicular hollows, or rounded holes, and sulfate concentrations, he said, are both features of desert soils on Earth.

Since Curiosity is currently on its way to Mount Sharp, future missions will be needed to fully explore these features. But as Retallack explained, the parallels with Earth are quite exciting:

None of these features is seen in younger surface soils of Mars. The exploration of Mars, like that of other planetary bodies, commonly turns up unexpected discoveries, but it is equally unexpected to discover such familiar ground.

The newly discovered soils indicate that more benign and habitable soil condition existed on Mars than previously expected. What’s more, their dating to 3.7 billion years ago places them within a transition period when the planet went from an early, benign water cycle to the acidic and arid Mars of today. This is especially important since major changes were taking place on Earth at around the same time.

Living-Mars.2Roughly 3.5 billion years ago, life on Earth is believed to have emerged and began diversifying. But some scientists have theorized that potential evidence that might indicate that life existed on Earth earlier may have been destroyed by tectonic activity, which did not occur on Mars. Basically, it may offer some credence to the theory that while flourished on Earth, it originated on Mars.

One person who supports this theory is Steven Benner of the Westheimer Institute of Science and Technology in Florida.  In the past, he has speculated that life is more likely to have originated on a soil planet like Mars than a water planet like Earth. In an email interview with Science Daily, Benner wrote that Retallack’s paper:

[S]hows not only soils that might be direct products of an early Martian life, but also the wet-dry cycles that many models require for the emergence of life.

So in addition to shedding light on the mysteries of Mars, Curiosity has also been pivotal in addressing some major questions which only increase the mystery of our own existence. Did life as we know it originate on Mars but flourish on Earth? Are there still some remnants of this microbial “Eden” being preserved deep within the soil and rocks? And could life exist there again some day?

All good questions that will no doubt keep robotic rovers, orbiters, landers, and even manned missions busy for many decades to come! In the meantime, check out the video from NASA’s Jet Propulsion Laboratory of Curiosity’s spark-generating laser blast being caught on tape:


Sources:
universetoday.com, sciencedaily.com

Exploring the Universe with Robotic Avatars and Holodecks

holodeck_nasaSpace exploration is littered with all kinds of hazards. In addition to the danger of dying from decompression, mechanical failures, micro-meteoroids or just crashing into a big ball of rock, there are also the lesser-known problems created by low-gravity, time dilation, and prolonged isolation. Given all that, wouldn’t it just be easier to send probes out to do the legwork, and use virtual technology to experience it back home?

That’s the idea being presented by Dr. Jeff Norris, one of the scientists who works for NASA’s Jet Propulsion Laboratory in Pasadena, California. In a recent presentation that took place at Pax Prime last year – entitled “NASA’s Got Game” – he spoke of the agency’s plans for telexploration – the process of exploring the universe using robotic avatars and holodecks, rather than sending manned flights into deep space.

avatar_imageIn the course of making this presentation, Norris noted several key advantages to this kind of exploration. In addition to being safer and cheaper, its also more readily available. Whereas deep space exploration involving space ships with FTL engines – the Alcubierre Drive they are currently working on – will eventually be available, robot space probes and advanced telecommunications technology are available right now.

At the same time, telexploration is also more democratic. Whereas conventional space travel involves a select few of highly-trained, eminently qualified people witnessing the wonders of the universe, robotic avatars and holographic representations bring the experience home, where millions of people can experience the awe and wonder for themselves. And when you think about it, it’s something we’re already doing, thanks to the current generation of space probes, satellites and – of course! – the Curiosity Rover.

Curiosity_selfportraitBasically, rather than waiting for the warp drive, Norris believes another Star Trek technology – the holodeck – will be the more immediate future of space exploration, one that we won’t have to wait for. Yes, there are more than a few Star Trek motifs going on in this presentation, and a little Avatar too, but that’s to be expected. And as we all know, life can imitate art, and the truth is always stranger than fiction!

Check out the video of the presentation below:


And remember…

holodeck_vegasad

Update on Asteroid Apophis: No Apocalypse by 2036

apophisDiscovered back in 2004, the Apophis asteroid garnered lots of attention when initial calculations of its orbit indicated that there was a 2.7 percent chance that it would hit Earth when it did a flyby in 2029. After running additional calculations based on the asteroids data, scientists were able to rule out a 2029 impact, but there was still a remote possibility that it might hit Earth during another flyby in 2036. However, that estimate has also been revised.

Thanks to the European Space Agency’s Herschel Space Observatory, a number of thermal infrared observations were captured of Apophis at different wavelengths. Taken together with optical measurements, Hershel was able to refine earlier estimates of the asteroid’s properties, which included its overall diameter. Initially, it was estimated to be 270 m on a side but now stands at a robust 325 m, an increased which translates into a 75% increase in its volume.

The thermal readings on the asteroid also provided a new estimate of the asteroid’s albedo, which is the a measure of its reflectivity. Knowing the thermal properties of an asteroid indicates how its orbit might be altered due to subtle heating by the Sun. Known as the Yarkovsky effect, the heating and cooling cycle of a small body as it rotates and as its distance from the Sun changes can instigate long-term changes to the asteroid’s orbit.

All of this taken together, has allowed NASA, the ESA and other space authorities to rule out the possibility of an impact by 2036 as well. Don Yeomans, manager of NASA’s Near-Earth Object Program Office at the Jet Propulsion Laboratory:

“We have effectively ruled out the possibility of an Earth impact by Apophis in 2036. The impact odds as they stand now are less than one in a million, which makes us comfortable saying we can effectively rule out an Earth impact in 2036. Our interest in asteroid Apophis will essentially be for its scientific interest for the foreseeable future.”

But the flyby on April 13, 2029 will be one for the record books, says NASA. On that date, Apophis will achieve the closest flyby of an asteroid of its size when it comes to within 31,300 kilometers (19,400 miles) of the Earth’s surface. And in the meantime, an smaller asteroid (40 meters in diameter) named 2012 DA14 will make an ever closer flyby as it passes Earth at a distance of 27,670 km (17,200 miles).

So people can rest, safe in the knowledge that no asteroids are likely to hit us anytime soon. But at the same time, apocalyptics can rest assured that there will be plenty of remote chances to exploit for the sake of their unusual brand of paranoia. As Yeomans said:

“With new telescopes coming online, the upgrade of existing telescopes and the continued refinement of our orbital determination process, there’s never a dull moment working on near-Earth objects.”

News From Mars!

An interesting slew of news has been coming from NASA recently, courtesy of the Curiosity Rover and its mission to Mars. First, there was the announcement by John Grotzinger on NPR radio that Curiosity’s science team had discovered something potentially “earth-shattering” on the Red Planet, which came just two days ago. Since then, researchers over at NASA have been keeping a tight lip on what that might be, though it seems to be taking an extraodinary effort to do so. One can only imagine what they’re dying to tell us…

But it seems more stories are coming in the wake of this. First, there was the revelation by the Curiosity Rover that Mars radiation levels, once thought to be problematic for life, are actually safe for humans. According to Don Hassler, the principal investigator on Curiosity’s Radiation Assessment Detector instrument (RAD), Curiosity determined that “the Mars atmosphere is acting as a shield for the radiation on the surface and as the atmosphere gets thicker, that provides more of a shield and therefore we see a dip in our radiation dose.”

Apparently, the levels are equal to what astronauts deal with on the International Space Station, which means people in suits will be able to walk on the Red Planet safely once a manned mission is mounted. Knowing that they can conduct surveys on the surface without additional radiation shields should prove to be a boon for colonization as well. More settlers will certainly be drawn to Mars now that they know they can settle in without having to worry about little things like radiation sickness or mutations!

Third, there was the news that in the wake of making its “one for the history books” discovery, that Curiosity has finished collecting and analyzing soil samples and is preparing to move on. The final checks and preps were made amidst ethereal whirlwinds and twisters, which are characteristic of the region known as the “Gale Crater”, where it has been conducting its research for the past month. The rover is now being prepared to move on in search of suitable targets for a compact rock drill, the final major sample acquisition system to be tested.

Ashwin Vasavada, the deputy project scientist for the Mars Science Laboratory rover at the Jet Propulsion Laboratory in Pasadena, Calif, had this to say on the next phase of the mission: “We still would like to get a little further into this Glenelg region where we see this diversity of rocks and layered rocks and other really interesting terrain. And then we still have a goal in the next month or two of doing the big U-turn and heading up to Mount Sharp.”

Mount Sharp is a 3-mile-high mound of layered terrain that sits in the center of the Gale Crater, where Curiosity is expected to spend the bulk of its planned two-year mission. In the meantime, the research team needs to go over all the information Curiosity has sent back, including an ongoing analysis of the martian weather.

On top of all that, there’s still the matter of that “earth shaking news”. How about it NASA? You too, Grotzinger? We’re ready and waiting… how much more time do your researchers need before they’re sure and are free to break the news they are so clearly dying to share? I still say its organic molecules, but what do I know?

Source: news.cnet.com