Archive for August, 2017

Curiosity Navcam Left B image taken on Sol 1800, August 29, 2017.
Credit: NASA/JPL-Caltech

Now performing Sol 1802 duties, NASA’s Curiosity’s Mars rover drove on Sol 1801 bringing it to an excellent location for contact and remote science as part of a 3-sol plan that sets up the robot for a long Labor Day weekend.

That’s the report from Rachel Kronyak, a planetary geologist from the University of Tennessee in Knoxville.

Murray bedrock

The plan called for kicking off Sol 1802 with contact science, using Curiosity’s Mars Hand Lens Imager (MAHLI) plus the Alpha Particle X-Ray Spectrometer (APXS). The target is called “Tyler” – a region of Murray bedrock just in front of the rover.

Curiosity Mastcam Left image acquired on Sol 1800, August 29, 2017.
Credit: NASA/JPL-Caltech/MSSS

“We’ll then enter into a very full, science-packed remote science block,” Kronyak notes, during which the rover will make Chemistry and Camera laser-induced breakdown spectroscopy (ChemCam LIBS) observation on Tyler and take a number of Mastcam mosaics.

“These mosaics will look at sedimentary structures and layering within the beautifully exposed rocks of the Vera Rubin Ridge in front of us,” Kronyak adds. The mosaics are fairly extensive and will document the targets named “Pettegrove Point,” “Rumills Hub,” “Mink Rocks,” “The Downfall,” and “Popplestone Ledge.”

Stereo mosaics

“Most of the Mastcam observations in the plan are actually stereo mosaics, which means we take each image with both the left and right eyes of Mastcam,” Kronyak explains. “Stereo mosaics are pretty resource intensive, but they provide us with three-dimensional depth information, which is especially useful for making geologic interpretations.”

Curiosity Front Hazcam Left B image taken on Sol 1800, August 29, 2017.
Credit: NASA/JPL-Caltech

 

Following Curiosity’s heavy science block, the robot will drive and collect standard post-drive images to set up for contact and remote science over the weekend. Also on tap is a post-drive Dynamic Albedo of Neutrons (DAN) and Rover Environmental Monitoring Station (REMS) observations, Kronyak concludes.

Curiosity ChemCam Remote Micro-Imager photo taken on Sol 1800, August 29, 2017.
Credit: NASA/JPL-Caltech/LANL

We’ll also do a post-drive DAN active along with our standard DAN passive and REMS observations.

It’s a big Universe – anybody out there?
Credit: Space Telescope Science Institute

The “Breakthrough Listen” campaign, a project to find signs of intelligent life in the universe, has detected 15 fast radio bursts (FRBs) emanating from the mysterious “repeater” FRB 121102.

Could these brief, bright pulses of radio emission from distant galaxies be signatures of extraterrestrial technology?

Breakthrough Listen is a global astronomical initiative launched in 2015 by Internet investor and philanthropist Yuri Milner and cosmologist Stephen Hawking.

Green Bank Telescope (GBT) telescope, located in West Virginia.
Credit: NSF

Telescope observations

Breakthrough Listen announced today that West Virginia-based Green Bank Telescope observations of a dwarf galaxy three billion light years away reveal 15 bursts of radio emission. This is the first time bursts from this source have been seen at these frequencies.

The Listen science team at UC Berkeley added FRB 121102 to their list of targets. In the early hours of Saturday, August 26, UC Berkeley Postdoctoral Researcher Vishal Gajjar observed the location of FRB 121102 using the Breakthrough Listen digital backend instrument at the Green Bank facility.

New pulses

Analysis by Gajjar and the Listen team revealed 15 new pulses from FRB 121102. As well as confirming that the source is in a newly active state, the high resolution of the data obtained by the Listen instrument will allow measurement of the properties of these mysterious bursts at a higher precision than ever possible before.

Credit: Breakthrough Initiative

The Listen backend, which is able to record several gigahertz of bandwidth at a time, split into billions of individual channels, enable a new view of the frequency spectrum of FRBs, and should shed additional light on the processes giving rise to FRB emission.

Possible explanations

Whether or not FRBs are indeed signatures of extraterrestrial technology remains a TBD, according to Breakthrough Listen.

Credit: Breakthrough Listen

According to a press statement released today: “Possible explanations for FRBs range from outbursts from rotating neutron stars with extremely strong magnetic fields, to more speculative ideas that they are directed energy sources used by extraterrestrial civilizations to power spacecraft.”

Observations may indicate FRB 121102 is currently in a heightened activity state, notes Gajjar “and follow-on observations are encouraged, particularly at higher radio frequencies.”

Resources

The new results are reported as an Astronomer’s Telegram and will be described in further detail in an upcoming scientific journal article.

Go to: http://www.astronomerstelegram.org/?read=10675

Also, go to this Breakthrough Listen-provided linked graphic that shows 14 of the 15 detected bursts in succession, illustrating their dispersed spectrum and extreme variability:

https://storage.googleapis.com/frb121102/FRB121102_Cband_GB.gif

For additional information on the various Breakthrough Initiatives, go to:

http://breakthroughinitiatives.org/

 

Credit: NASA/JPL-Caltech/University of Arizona

Curiosity Navcam Left B image taken on Sol 1800, August 29, 2017.
Credit: NASA/JPL-Caltech

 

Curiosity Front Hazcam Right B image taken on Sol 1800, August 29, 2017.
Credit: NASA/JPL-Caltech

Curiosity Navcam Left B image taken on Sol 1800, August 29, 2017.
Credit: NASA/JPL-Caltech

Curiosity Rear Hazcam Right B image acquired on Sol 1800, August 29, 2017.
Credit: NASA/JPL-Caltech

Curiosity Navcam Left B image taken on Sol 1800, August 29, 2017.
Credit: NASA/JPL-Caltech

 

NASA’s Curiosity rover is in the early hours of performing Sol 1801 duties.

As the robot moves forward to ascend Vera Rubin Ridge, new imagery is helping scientists better understand how the ridge formed.

Projection of things to come. BTW: notice the SpaceX disappearing act from previous NASA charts and the addition of China for a return sample mission. Credit: NASA

 

NASA is blueprinting its beyond Mars 2020 rover plans, focusing on returning samples from the Red Planet.

In a “Review of Progress Toward Implementing the Decadal Survey Vision and Voyages for Planetary Sciences” briefing yesterday at the J. Erik Jonsson Woods Hole Center in Woods Hole, Massachusetts, Thomas Zurbuchen, NASA’s Science Mission Directorate Associate Administrator detailed some Mars sample return thinking.

 

 

Note:

Also, go to my earlier story that gives you the “inside scoop” on Mars sample return:

http://www.leonarddavid.com/sampling-mars-grab-and-go-back-to-earth/

China card

Interestingly, now infused on the NASA overview chart is China’s Mars plans of Red Planet exploration, including an orbiter, lander and sample return. Then there’s the missing-in-powerpoint projection of Elon Musk’s SpaceX Dragon landings.

Propulsive Platform Lander
Credit: NASA

Presently on the table are two NASA concepts that leverage Mars program legacy system capabilities to shoot back to Earth specimens of the Red Planet: a Propulsive Platform Lander and a Skycrane-Delivered Platform.

Skycrane-Delivered Platform
Credit: NASA

Here are a few briefing charts from Zurbuchen’s presentation on the NASA Mars exploration program.

Earth as seen from the Moon during the total eclipse on August 21, 2017. The shadow of the Moon is
centered over Hopkinsville, Kentucky (18:25:30.386 UTC or 1:25:30 pm Central Daylight Time in
Kentucky) Credit: NASA/GSFC/Arizona State University).

NASA’s Lunar Reconnaissance Orbiter (LRO) used its LROC imaging system to look back at Earth and snag imagery during the Great American Solar Eclipse on August 21.

As LRO crossed the lunar south pole heading north at 3,579 miles per hour (1600 meters per second, the shadow of the Moon was racing across the United States at 1,500 miles per hour (670 meters per second).

A few minutes later, LRO began a slow 180° turn to look back at the Earth and capture an image of the eclipse very near the spot of maximum length of totality.

Credits: NASA/GSFC/Arizona State University).

The Lunar Reconnaissance Orbiter Camera’s (LROC) Narrow Angle Camera began scanning the Earth at 18:25:30 UTC and completed the image 18 seconds later (UTC is 4 hours ahead of Eastern Daylight Time, or 7 hours ahead of Pacific Daylight Time).

Typical day on Moon

“While all of Monday’s thrill was in experiencing the shadow of the Moon sweep across us on Earth, on the Moon this was just another typical day,” said Mark Robinson of Arizona State University, and principal investigator of the Lunar Reconnaissance Orbiter Camera.

“The lunar nearside was one week into its two-week night, while the Sun shone on the farside in the middle of its two-week day. For the Moon, and the LRO spacecraft observing the Moon, the real excitement is during a lunar eclipse when the shadow of the Earth sweeps across the Moon.”

Lunar Reconnaissance Orbiter (LRO).
Credit: NASA/GSFC

 

Temperature drop

Robinson added that during the eclipse, the lunar surface temperatures drop rapidly and LRO’s thermal imager, the Diviner Lunar Radiometer, can learn about the material properties of the lunar rocks and soils by studying their temperature just after the lights abruptly go out.

“Though for the LRO spacecraft itself, the Earth’s shadow means that most of the other instruments must be powered down because of the lack of power coming from the solar panels,” Robinson pointed out.

Launched on June 18, 2009, LRO has collected a treasure trove of data about the Moon with its seven powerful instruments. LRO is managed by NASA’s Goddard Space Flight Center in Greenbelt, Maryland, for the Science Mission Directorate at NASA Headquarters in Washington, D.C.

Curiosity Front Hazcam Right B image acquired on Sol 1799, August 28, 2017.
Credit: NASA/JPL-Caltech

 

 

NASA’s Curiosity Mars rover is now closing out Sol 1799 duties.

The robot drove some 76 feet (23.3 meters) over the weekend bringing the robot even closer to the area it will ascend Vera Rubin Ridge.

“We have reached the point in the traverse where we are no longer headed east along the ridge, but instead are turning to the south where orbital data show the ridge has slopes shallow enough for Curiosity to climb,” reports Abigail Fraeman, a planetary geologist at NASA/Jet Propulsion Laboratory in Pasadena, California.

Curiosity Navcam Left B image taken on Sol 1799, August 28, 2017.
Credit: NASA/JPL-Caltech

Charge of the batteries

Curiosity acquired Mastcam and ChemCam Remote Micro-Imager (RMI) images of the ridge in the weekend plan, including a last “official” approach imaging mosaic.

“These images continue to show very interesting, fine scale sedimentary structures that hold the secrets of how the lower ridge layers were deposited,” Fraeman notes.

One of the big challenges putting a new plan together was making sure the observations researchers wanted didn’t leave the rover’s batteries too drained at the end of the plan.

Curiosoty Navcam Right B image taken on Sol 1799, August 28, 2017.
Credit: NASA/JPL-Caltech

“We keep careful track of the expected state of charge of the batteries because we want to make sure they will last a long time, and because we want to have enough power available going into the next sol’s plan,” Fraeman points out. “Getting everything to fit inside power guidelines was challenging today in part because late autumn has come to Gale Crater. Colder temperatures mean we have to run heaters for longer, which takes more energy.”

 

Two sol script

A two sol plan has been scripted, starting off on Sol 1800 with contact science, including Mars Hand Lens Imager (MAHLI) and Alpha Particle X-Ray Spectrometer (APXS) observations of an interesting eroded Murray formation rock target named “Bauneg Beg.”

Following the contact science, Curiosity is to make ChemCam LIBS [laser-induced breakdown spectroscopy] observations of targets “Bucklin Rock” and “Gilkey Harbor,” and then take a 12×1 Mastcam right eye mosaic that will cover the area directly in front of the rover. Bucklin Rock looks similar to Bauneg Bag, and Gilkey Harbor is a dark, smooth rock.

Wheel inspection via Curiosity’s Mars Hand Lens Imager (MAHLI). This photo acquired Sol 1798, August 27, 2017. MAHLI is located on the turret at the end of the rover’s robotic arm.
Credit: NASA/JPL-Caltech/MSSS

Southward ho

“After our morning science, Curiosity will drive south towards Vera Rubin Ridge,” Fraeman adds.

“After the drive on sol 1801, Curiosity will do some untargeted remote sensing, including collecting some data from the ChemCam calibration targets, and taking a Navcam suprahorizon movie, performing a dust devil search, and looking at the Sun to assess the amount of dust in the atmosphere (a tau measurement),” Fraeman concludes.

Italian ESA astronaut Paolo Nespoli remote-controlled the Rollin’ Justin robot from the ISS.
Credit: NASA/DLR

A humanoid robot that can be used for future Mars exploration has been operated from the International Space Station (ISS).

On August 25, Italian ESA astronaut Paolo Nespoli remote-controlled the “Rollin’ Justin” robot, research work underway at the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt; DLR).

On a roll. Enter Rollin’ Justin.
Credit: DLR (CC-BY 3.0)

Delegate duties

The effort is designed to demonstrate from Mars orbit that astronauts can dispatch a robot to different positions on the planet without actually having to land and visit the site.

Instead, the astronaut-driver would monitor the process and send instructions that lay out the sequence of tasks to the robot. Activities that would be dangerous for astronauts can also be delegated to the robot.

The long-term objective of the project is to enable human/robot collaboration to colonize distant worlds.

Maintenance of a solar panel by Rollin’ Justin. Robot has connected itself to a solar panel and is reading out data. The robotic co-worker then carries out the any needed fixes in accordance with error analoysis.
Credit: DLR (CC-BY 3.0)

Servicing a solar farm

During the experiment, a tablet-PC was used to send instructions to the robot at the DLR Institute of Robotics and Mechatronics in Oberpfaffenhofen, Germany from the ISS.

The Justin robot was then left to its own devices in the completion of various tasks and was required to use artificial intelligence to decide how individual work stages needed to be completed.

In the first experiment in the series, ISS crewmate Nespoli ordered Rollin’ Justin to service a solar farm set up specifically in the laboratory in Oberpfaffenhofen to check the condition of several solar panels and to repair any faults.

 High-performance, local intelligence

This research is on-going, enabled by the SUPVIS (Supervisory Control) Justin experiment, which is being carried out as part of the Multi-Purpose End-to-End Robotic Operation Network (Meteron) in cooperation with the European Space Agency (ESA).

DLR’s robot “Rollin’ Justin” is investigating human-machine interaction for Mars exploration.
Credit: DLR (CC-BY 3.0)

“In the SUPVIS Justin experiment, we are laying the foundation for cooperation between astronauts and intelligent, humanoid robots in the colonization of distant planets and moons,” says Alin Albu-Schäffer, director of the DLR Institute of Robotics and Mechatronics in a press statement. “The robots are equipped with high-performance local intelligence, so the astronaut only needs a tablet-PC to instruct the robot in the performance of complex activities.”

Adds DLR research team leader, Neal Lii: “We intend to use this project to cross new frontiers and to transform robots into true co-workers for a variety of tasks in aerospace. In the long term, this should ease the strain on astronauts in the area of planetary exploration.”

Humans on Mars operations – the reach for the Red Planet – how soon and why?
Credit: Boeing

 

I am delighted to announce that I’ll be talking at Seattle’s Museum of Flight, an event being held Saturday, October 7, 2017, 5:30 PM – 8:30 PM.

My talk is being staged at the Charles Simonyi Space Gallery at the Museum of Flight – the largest independent, non-profit air and space museum in the world, housing over 175 aircraft and spacecraft, tens of thousands of artifacts, millions of rare photographs, and dozens of exhibits and experiences.

Credit: NASA

Reception, lecture, book signing

Come join me for an evening reception, lecture and book signing and discussion about my book, Mars: Our Future on the Red Planet. It is the companion book to the National Geographic six-part MARS series with Ron Howard, whose foreword opens the book with work now underway as the MARS television production is readying its second season.

I’ll offer the latest news on Mars exploration, the potential for use of the Moon as testing ground to enable the reach for the Red Planet, as well as the prospects and problems of settlement of humans on Mars.

Information

For ticket details, go to:

https://www.museumofflight.org/Plan-Your-Visit/Calendar-of-Events/3464/mars-our-future-on-the-red-planet/

For general information about the Museum of Flight in Seattle, Washington, go to:

https://www.museumofflight.org/

 

View from Curiosity’s Mast Camera (Mastcam) shows a site with a network of prominent mineral veins below a cap rock ridge on lower Mount Sharp. Using the robot’s Alpha Particle X-Ray Spectrometer (APXS) instrument, scientists have discovered unusual material in these veins that has the highest germanium concentrations found in Gale Crater.
Credit: AGU/NASA

 

NASA’s Curiosity Mars rover is now performing Sol 1798 science duties.

In newly released data from Curiosity, scientists report a potential history of hydrothermal activity at Gale Crater on the Red Planet, a finding that broadens the variety of habitable conditions once present there.

The new study has been published in the Journal of Geophysical Research: Planets, a journal of the American Geophysical Union (AGU). The new measurements come from the Alpha Particle X-Ray Spectrometer (APXS) on Curiosity.

Zinc and germanium

According to an AGU statement on the group’s “Blogosphere,” researchers found concentrations of the elements zinc and germanium to be 10 to 100 times greater in sedimentary rocks in Gale Crater compared to the typical Martian crust.

Curiosity Front Hazcam Right B image taken on Sol 1797, August 26, 2017.
Credit: NASA/JPL-Caltech

Zinc and germanium tend to be enriched together in high temperature fluids and often occur together on Earth in hydrothermal deposits containing sulfur. The elevated concentrations of zinc and germanium in Gale Crater can potentially be explained by hydrothermal activity that occurred in the region, the new research suggests.

Evidence preserved?

“Extreme thermal environments on Earth are home to a diverse array of microbial life adapted to these conditions, and these organisms may have been some of the first to evolve on Earth,” notes the AGU.

Curiosity Mastcam Left image taken on Sol 1796, August 25, 2017.
Credit: NASA/JPL-Caltech/MSSS

Now with potential evidence for hydrothermal conditions once present inside or near Gale Crater, Curiosity’s mission takes another step toward determining if there were favorable environmental conditions for microbial life on Mars, explains Jeff Berger, a geologist at the University of Guelph, in Ontario, Canada and lead author of the new study.

Curiosity Navcam Left B image taken on Sol 1796, August 25, 2017.
Credit: NASA/JPL-Caltech

Hydrothermal deposits are more likely to preserve evidence of microbial life or its precursors, according to Berger. “You have heat and chemical gradients…conditions favorable for the genesis and persistence life,” he said.

Curiosity ChemCam Remote Micro-Imager photo acquired on Sol 1797, August 26 2017.
Credit: NASA/JPL-Caltech/LANL

 

New road map

A new Curiosity traverse map has been released, indicating the route driven by the robot through Sol 1796 (August 25, 2017).

Numbering of the dots along the line indicate the sol number of each drive. North is up.

The scale bar is 1 kilometer (~0.62 mile).

Self-inspection for wheel wear. Curiosity Mars Hand Lens Imager (MAHLI) photo taken on Sol 1798, August 27, 2017.
Credit: NASA/JPL-Caltech/MSSS

 

 

 

Total odometry

From Sol 1795 to Sol 1796, Curiosity had driven a straight line distance of about 56.12 feet (17.11 meters), bringing the rover’s total odometry for the mission that began in August 2012 to 10.72 miles (17.26 kilometers).

Credit: NASA/JPL-Caltech/University of Arizona

The base image from the map is from the High Resolution Imaging Science Experiment Camera (HiRISE) in NASA’s Mars Reconnaissance Orbiter.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Resources

The new AGU-published research “Zinc and germanium in the sedimentary rocks of Gale Crater on Mars indicate hydrothermal enrichment followed by diagenetic fractionation” is available at:

http://onlinelibrary.wiley.com/doi/10.1002/2017JE005290/abstract

Mars true-color globe showing Terra Meridiani.
Credits: NASA/Greg Shirah

 

There’s a biological battle brewing involving life on Mars, decades-old Viking Mars data, projected return to Earth of Martian samples, as well as future robotic looks for life on ocean-worlds.

At the nexus of the debate is whether or not planetary protection rules are stifling our exploratory space missions.

Loosen restrictions?

For example, in the August 11 issue of Science, staff writer Paul Voosen wrote about the fear of microbial taint that curbs Mars explorers.

Look, but do not touch? NASA’s Curiosity rover is on the prowl within Gale Crater/Mt. Sharp area that appears to have Recurring Slope Lineae (RSL).
Credit: NASA/JPL-Caltech

In summary, the Science story explains: “In the coming years, NASA’s Curiosity rover will pass rocks on Mars that, seen from orbit, seem to host mysteriously intermittent dark streaks – perhaps marking seasonal water seeps that could host martian life. But NASA’s planetary protection office, charged with keeping earthly microbes from colonizing other bodies, has said it may nix a visit. It fears that Curiosity could contaminate this so-called special region because the rover was not fully sterilized before launch.”

The Science article summary explains that “many planetary scientists, however, believe that now is the time to loosen restrictions on visiting these areas, before human exploration contaminates the planet. And, after years of stasis, the planetary protection office seems primed for a shakeup, thanks to an internal move and potential change in leadership, along with outside review of its policies by independent scientists.”

NASA’s two Viking landers were designed and built by Martin Marietta (now Lockheed Martin) at its facility near Denver. This image shows some Martin Marietta employees in a Viking lander test center.
Credit: Lockheed Martin

Upcoming article

Stepping into the astrobiological discussion is an upcoming commentary next week in the journal Astrobiology by Alberto G. Fairén, a visiting scientist at Cornell University. It reportedly questions the Committee on Space Research (COSPAR)-imposed and NASA-accepted requirement for sterilization of spacecraft landing on Mars.

That prospect and the Science article has stirred up the International Committee Against Mars Sample Return (ICAMSR), issuing an August 20 statement titled: “Veteran Astrobiologists Criticize Article Calling for Relief of Anti-Contamination Requirements for the Return Mars Sample Mission.”

This retort is led by Gilbert Levin, experimenter on the Viking Labeled Release Life Detection Experiment – one experiment among a package of devices that landed on Mars in 1976 via two Viking landers. Levin is now an adjunct professor at Arizona State University.

 

Strong evidence for Mars life?

“The contention is made that the extreme unlikeliness that Earth microorganisms could survive on Mars makes spacecraft sterilization unnecessary, and imposes a high cost on such missions,” the ICAMSR statement explains.

It continues, noting that the Science magazine article points to the Viking Mars landers as an example of the high cost of spacecraft sterilization.

That article “neglects to say that the Viking Labeled Release (LR) experiment found strong evidence for extant microbial life on the surface of Mars,” the ICAMSR statement points out. “The results were not accepted by NASA, because Viking failed to find organic matter in the Martian material…and in the 41 years since Viking, NASA has rejected all proposals for further life detection experiments to confirm or deny the LR findings. Moreover, none of the attempts to duplicate the LR results has succeeded.”

Loaded to the brim with samples, a robotic Mars Ascent Vehicle rockets off the planet under the watchful eye of an accompanying mini-rover.
Credit: NASA/JPL

Cavalier return of Mars samples

Other landers since Viking have found organic matter on Mars, adds the ICAMSR statement, supporting the contention that the Viking LR detected life.

Therefore, continues the ICAMSR statement, a small chance that life exists on Mars “should prohibit a cavalier return of Mars material to Earth because of the horrendous damage to Earth’s biosphere potential Martian microorganisms might do if they were pathogenic.”

The Andromeda Strain – the 1971 movie, but how real for a 21st century return to
Earth of Mars samples?
Credit: Universal Pictures

All that said, Levin and Patricia Straat, co-experimenter on the Viking Labeled Release Life Detection Experiment, now retired, argue for the “classical dictate of science: when an experiment produces a new result, repeat that experiment to check its validity, and, if it proves true, expand the experiment to gain new facts.”

Note that both Levin and Straat are science advisors for the International Committee Against Mars Sample Return (ICAMSR), but have no financial interest in ICAMSR.

Other worlds

Another biological shoe to drop is whether the exploration of other worlds beyond Mars is also being inhibited by too stringent of planetary protection rules – such as investigating Europa, a moon of Jupiter, or Saturn’s Enceladus?

This artist’s rendering shows a NASA concept of a Europa lander.
Credit: NASA/JPL-Caltech/M. Carroll

Earlier this year, at the Astrobiology Science Conference (AbSciCon) held in Mesa, Arizona, Brent Sherwood, a program manager at NASA’s Jet Propulsion Laboratory, was lead author of a paper noting that the planetary-protection requirement governing future ocean-worlds exploration missions limits to one in ten thousand the probability that a single viable Earth organism will enter an alien liquid water reservoir.

“This 10-4 requirement, enforceable under international treaty, binds NASA,” the paper explains. “Many aspects of projects intended to explore Europa, Enceladus, and other potentially habitable ocean worlds revolve around this single requirement. Thus, it is important both to understand its origin and periodically to revisit the assumptions behind it.”

To view the Science article, go to:

http://science.sciencemag.org/content/357/6351/535

Go to the International Committee Against Mars Sample Return (ICAMSR) at:

http://www.icamsr.org/news.html

Also, go to The overprotection of Mars commentary in Nature Geoscience by Alberto G. Fairén and Dirk Schulze-Makuch at:

http://www.nature.com/ngeo/journal/v6/n7/full/ngeo1866.html

Griffith Observatory Event