Leak in Curiosity's Wet Chemistry Test Finds Mars Organics
An unexpected leak of a chemical designed to tag complex organic molecules in samples collected by NASA’s Mars rover Curiosity appears to have serendipitously done its job
An unexpected leak of a chemical designed to tag complex organic molecules in samples collected by NASA's Mars rover Curiosity appears to have serendipitously done its job, scientists reported on Tuesday.
Curiosity's onboard laboratory includes seven so-called "wet chemistry" experiments designed to preserve and identify suspect carbon-containing components in samples drilled out from rocks.
None of the foil-capped metal cups has been punctured yet, but vapors of the fluid, known as N-methyl-N-tert-butyldimethylsilyl-trifluoroacetamide, or MTBSTFA, leaked into the gas-sniffing analysis instrument early in the mission.
Curiosity landed in a 96-mile wide impact basin known as Gale Crater in August 2012 to determine if the planet most like Earth in the solar system has or ever had the chemistry and environments to support microbial life.
Scientists quickly fulfilled the primary goal of the mission, discovering sulfur, nitrogen, hydrogen, oxygen, phosphorus and carbon in powder Curiosity drilled out of an ancient mudstone in an area known as Yellowknife Bay.
That paved the way for a more ambitious hunt for complex organic molecules, an effort complicated by the MTBSTFA leak.
"This caused us a lot of headache in the beginning, frankly, because it has a lot of carbon in it and other (chemical) fragments that can break apart," Curiosity scientist Danny Glavin, with NASA's Goddard Space Flight Center in Greenbelt, Maryland, said on Tuesday (March 17) at the Lunar and Planetary Science conference in Houston, Texas.
"We've turned this sort of bad thing into a good thing because we've learned how to work around this leak. We've actually used this vapor from this leak to carry out derivitization," he said, referring to the technique to tag organics.
Samples drilled out from Yellowknife Bay were stored inside the Sample Analysis at Mars, or SAM instrument, as the rover made its way over the next two years to Mount Sharp, a three-mile high mound of sediments rising from the floor of Gale Crater.
"These samples were just reacting with this MTBSTFA vapor, reacting with all that good organic stuff. That turned out to be a good thing," Glavin said.
Scientists figured out how to extract the enriched vapor, collect it and analyze it in a way that preserved the organics.
In addition to analyzing the doggy-bagged sample that had been reacting with the MTBSTFA vapors for two years, scientists also were able to compare the results with residue from a sample that had been heated twice, effectively killing off any volatiles, but which also had been exposed to the vapors for two years.
Initial results show indigenous Mars complex organics in the fresh sample, though more work is needed to definitely peg the compounds.
"It's probably going to be years of work trying to disentangle this story," said Glavin.
"This is really exciting stuff. We've got a mudstone on Mars in a habitable environment. There was a lake there at one point. We've got organic molecules, possibly some interesting ones, of astrobiological interest. Bottom line, this sample has an even more diverse set of organic compounds than we previously thought.
"Million dollar question? Is this biological or not. I wish I had an answer I can't tell you. We've got basically a few compounds that we're dealing with here. You probably need a lot more before you can start discriminating between biological and non-biological origin," Glavin added.
This image from NASA's Curiosity rover shows the first sample of powdered rock extracted by the rover's drill from the Yellowknife study site. Curiosity used its Mastcam on Sol 193 (Feb. 20, 2013) of its mission to capture this photo.
As 2014 draws to a close and we look forward to another 12 months of incredible astronomical discoveries, physics revelations, space flight advances and solar system exploration, we turned to our readers to find out what YOUR top space story was for the year. The last year has, after all, been very busy for space, so we’ve collected your nominations via social media, weighed the nominations against web traffic statistics and arrived at our annual Top 10 Reader’s Choice. Which space story do
think made it to #1?
Read on to find out.
Next year will be the year of the dwarf planet. First, in March 2015, we have NASA’s Dawn mission, fresh from orbiting massive asteroid Vesta, entering orbit around the solar system’s innermost dwarf planet Ceres that resides in the asteroid belt between Mars and Jupiter. We’ve never seen Ceres up-close, so this solar system encounter will be one for the history books. Then, in July, NASA’s New Horizons mission will make its much anticipated flyby of Pluto and then careen through the unexplored Kuiper Belt. Every Pluto-related article this year has been popular, but as New Horizons flew through Neptune’s orbit in August, and then started to image the space around Pluto, spying its tiny moon Hydra and then spotting Pluto-Caron ‘wobble’, your fascination was piqued, making these articles some of the most popular of the year.
NASA’s veteran Saturn orbiter Cassini has been hard at work this year, continuing to give us unprecedented access to the science behind the gas giant’s stormy atmosphere, its rings and extensive system of moons. But one of Saturn’s moons always draws the most attention. Of course, that moon is Titan. Enshrouded with a thick atmosphere (the only moon in the solar system to have an atmosphere with its own weather and climate systems), Titan can sustain vast lakes of liquid methane and ethane on the hydrocarbon-rich surface -- features that have been the focus of many Cassini-Titan flybys, the 100th of which was celebrated in 2014. Of particular interest was one of this year’s biggest mysteries: Titan’s bizarre “Magic Island” that appeared and then disappeared in Cassini’s flyby imagery. So what is Magic Island? The jury is still out, but we’re pretty sure it’s not a Titanian Loch Ness Monster.
Is it all just a universal storm in a cosmic teacup? Or did the South Pole-based BICEP2 telescope
detect the signature of gravitational waves in its observations of the polarization of the cosmic microwave background radiation? As it turns out, from a frantic mix of public announcements, scientific scrutiny and inevitable puzzlement, the complex BICEP2 research bled into the mainstream media this year and suddenly everyone knew what a gravitational wave was. As we wait for joint research between the BICEP2 and European Planck Telescope teams to be published -- hopefully working out once and for all whether the original BICEP2 results were actually caused by galactic dust -- though this may well be a false positive, this astrophysical story certainly grabbed our readers’ attention, firmly planting gravitational waves at #8 on our list.
This year marked an important event for NASA’s human spaceflight future: we saw an unmanned Orion test spacecraft blast into space atop a Delta IV Heavy rocket, taking it on a rollercoaster ride around Earth before testing out the largest heat shield ever constructed, bringing the capsule down to a Pacific Ocean splashdown. The Dec. 5 launch was a near perfect test flight, perhaps giving us a glimpse into NASA’s future deep space exploration plans as the US space agency plots its path to Mars. Whether you love it or hate it, it seems that Orion is here to stay and the politics that have erupted around NASA’s vision for its human spaceflight future will no doubt continue to simmer until we (hopefully) see boot prints in Martian dust.
When you hear “Kepler-186f”, what comes to mind? Well, to NASA, that name conjures images of lush green continents and blue oceans on an alien world orbiting a different star (looking at this artistic rendition, you can almost
the tropical sounds of alien creatures in the undergrowth). Yes, Kepler-186f is the most Earth-like exoplanet discovered to date. “Most Earth-like” isn’t a term that should be used lightly, however. Sure, this world orbits a sun-like star in an Earth-like orbit and it is kinda Earth-sized, but that is all the information we have -- there’s no way, currently, that we can probe that distant world’s atmosphere for the gases that may support life as we know it. We don’t even know if it has water on its surface, but if it does, its habitable zone location would give it a chance of hosting life-giving oceans. As NASA’s Kepler space telescope is given a new lease on life, the science of extrasolar planets and the hunt for a bona fide “Second Earth” continues to be one of the hottest topics in space science.
Did you know that Mars is littered with rocks? This may seem like a silly question, but when casually browsing the incredible high-resolution imagery from NASA’s Curiosity and Opportunity rovers, occasionally you start to see some really odd shapes. Known as pareidolia, that’s your brain tricking you into thinking random rocks are actually more familiar objects like faces, Yetis and rodents. But Opportunity’s “Mars jelly doughnut” was one rock that, initially, had even NASA scientists confused. It wasn’t so much that the doughnut-shaped rock looked like, well, a doughnut; it was more the fact that it magically “appeared” in front of the rover as it was maneuvering on the surface. How did it get there? Well, after some careful detective work, mission scientists realized that as the rover turned in place, one of Opportunity’s wheels must have flipped the rock from beneath the rover, landing it in sight of its cameras. Interestingly, the unlikely story of this little rock went viral, securing it a bizarrely strong position in the Top 10.
Over two years since landing on the Red Planet, NASA’s Mars Science Laboratory has accumulated an astounding amount of science that has revealed the planet was once habitable for life as we know it. After finally arriving at the base of Mount Sharp in September, the rover’s ultimate destination in the center of Gale Crater, mission scientists announced that analysis of sedimentary rock proves there was much more water filling the crater in Mars’ ancient past than previously thought. Then, only this month, mission managers made the groundbreaking announcement that the rover had found organics in drilled rock samples and had detected methane in the atmosphere. Were there once microbes living in the Martian surface layers? Could those microbes be eking out an existence today, producing organic methane gas? Until we send a microscope to Mars (or, even better, a microscope with a team of biologists), we’ll probably never know, although all the evidence is pointing to an ancient habitable Mars.
As Virgin Galactic geared up to send its first fee-paying space tourists on suborbital flights in 2015, a series of successful rocket-powered test flights of the company’s SpaceShipTwo boosted expectations that a new era of private spaceflight was on the horizon. Tragically, during a routine powered test flight of the vehicle on Oct. 31, an inflight anomaly saw SpaceShipTwo dramatically disintegrate over California’s Mojave Desert. 39 year-old co-pilot Mike Alsbury was killed and 43 year-old pilot Pete Siebold parachuted to safety, but suffered a serious shoulder injury. An investigation into the details of the accident is underway as the test flight and commercial spaceflight communities mourn the loss of one of their own. This sad event came less than a week after an unmanned commercial Antares rocket exploded during launch from Wallops Island Flight Facility in Virginia. The Orbital Sciences Corp. launch was a contracted cargo run to the International Space Station for NASA.
One of the stand-out spaceflight successes of the year is the Indian Space Research Organization’s Mars Orbiter Mission (MOM). On the nation’s first Mars mission attempt, the ISRO did what only three other space organizations (NASA, ESA and Russia/Soviets) have achieved. Arriving in Mars orbit on Sept. 23, just two days after NASA’s MAVEN mission arrived at Mars, MOM immediately started to send back data. A few days later, stunning images of the Martian globe wowed the world. MOM’s highly elliptical orbit allows much more of the planet to be observed and its data complements observations being made by the four other NASA and ESA satellites that are currently operational in Mars orbit. The $74 million MOM is mainly a technology demonstration, but it is also a lesson to the world that India is a growing space research powerhouse capable of doing mighty things throughout the solar system.
Really, did you have any doubt about which space story would clinch the #1 spot? The touch-down of the Rosetta mission’s Philae lander on the surface of Comet 67P/Churyumov-Gerasimenko on Nov. 12 was nothing short of epic. After catching up with the icy cometary mass, Rosetta carried out a series of maneuvers that set the mission up for its dramatic attempt to make a soft landing on a comet for the first time in history. But Rosetta wouldn’t be landing on the comet itself. Attached to the spacecraft was Philae, a small lander. With the help of ESA’s expertise on social media and continuous blog updates, Philae quickly captivated the world as the little lander that was about to conquer a massive comet. And conquer it did, but not before one of the most dramatic landings in space history. After analyzing Philae’s telemetry, mission scientists realized that Philae had bounced three times before coming to rest against the slope of a crater rim. Although the lander had enough batter power for a couple of days, for the lander to survive any longer, its solar panels needed to be correctly positioned so they could charge. Sadly, Philae was caught in a shadow and after several attempts to optimize the sunlight across the solar array, Philae’s batteries drained and the lander dropped into hibernation. However, Philae feverishly collected as much data as it could before power loss and scientists will be busy for some time understanding the nature of Comet 67P, the first comet a robot has ever grabbed.