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Space News Update — October 25, 2019 —

Contents

In the News

Story 1: New VIPER Lunar Rover to Map Water Ice on the Moon

Story 2:

NASA Moon Rocks Help Form New Picture of Early Moon and Earth

Story 3: Beyond Jupiter, Researchers Discover a 'Cradle of Comets'

Departments

The Night Sky

ISS Sighting Opportunities

Space Calendar

NASA-TV Highlights

Food for Thought

Space Image of the Week

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1. New VIPER Lunar Rover to Map Water Ice on the Moon

NASA is sending a mobile robot to the South Pole of the Moon to get a close-up view of the location and concentration of water ice in the region and for the first time ever, actually sample the water ice at the same pole where the first woman and next man will land in 2024 under the Artemis program.

About the size of a golf cart, the Volatiles Investigating Polar Exploration Rover, or VIPER, will roam several miles, using its four science instruments — including a 1-meter drill — to sample various soil environments. Planned for delivery to the lunar surface in December 2022, VIPER will collect about 100 days of data that will be used to inform the first global water resource maps of the Moon.

“The key to living on the Moon is water – the same as here on Earth,” said Daniel Andrews, the project manager of the VIPER mission and director of engineering at NASA’s Ames Research Center in Silicon Valley. “Since the confirmation of lunar water-ice ten years ago, the question now is if the Moon could really contain the amount of resources we need to live off-world. This rover will help us answer the many questions we have about where the water is, and how much there is for us to use.”

NASA's Artemis program begins a new era where robots and humans working together will push the boundaries of what’s possible in space exploration. In collaboration with commercial and international partners, NASA’s ambition is to achieve a long-term sustainable presence on the Moon – enabling humans to go on to Mars and beyond.

Scientists had long considered the lunar poles as promising spots to find water ice – a resource of direct value for humans that could provide oxygen to breathe and hydrogen and oxygen to fuel future landers and rockets. The Moon’s tilt creates permanently shadowed regions where water ice from comet and meteor impacts, as well as the Sun’s interaction with the lunar soil, can collect without being melted by sunlight. In 2009, NASA crashed a rocket into a large crater near the South Pole and directly detected the presence of water ice. Data from this mission and other orbiters have confirmed that the Moon has reservoirs of water ice, potentially amounting to millions of tons. Now, we need to understand the location and nature of the water and other potentially accessible resources to aid in planning how to extract and collect it.

“It’s incredibly exciting to have a rover going to the new and unique environment of the South Pole to discover where exactly we can harvest that water,” said Anthony Colaprete, VIPER’s project scientist. “VIPER will tell us which locations have the highest concentrations and how deep below the surface to go to get access to water.”

To unravel the mysteries of the Moon’s South Pole, the rover will collect data on different kinds of soil environments affected by light and temperature – those in complete darkness, occasional light and in direct sunlight. By collecting data on the amount of water and other materials in each, NASA can map out where else water likely lies across the Moon.

As the rover drives across the surface, it will use the Neutron Spectrometer System, known as NSS, to detect “wet” areas below the surface for further investigation. VIPER will then stop and deploy a drill, The Regolith and Ice Drill for Exploring New Terrain, or TRIDENT, developed with Honeybee Robotics, to dig up soil cuttings

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from up to a meter beneath the surface. These drill samples will then be analyzed by two instruments: the Mass Spectrometer Observing Lunar Operations, or MSolo, developed out of NASA’s Kennedy Space Center; and the Near InfraRed Volatiles Spectrometer System, known as NIRVSS, developed by Ames. MSolo and NIRVSS will determine the composition and concentration of potentially accessible resources, including water,that were brought up by TRIDENT.

VIPER is a collaboration within and beyond the agency. VIPER is part of the Lunar Discovery and Exploration Program managed by the Science Mission Directorate at NASA Headquarters. Ames is managing the rover project, leading the mission’s science, systems engineering, real-time rover surface operations and software development. The hardware for the rover is being designed by the Johnson Space Center, while the instruments are provided by Ames, Kennedy, and commercial partner, Honeybee Robotics. The spacecraft lander and launch vehicle that will deliver VIPER to the surface of the Moon, will be provided through NASA’s Commercial Lunar Payload Services (CLPS) contract, delivering science and technology payloads to and near the Moon.

Source: NASA Return to Contents

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2. NASA Moon Rocks Help Form New Picture of Early Moon and Earth

Most people only ever encounter rubidium as the purple color in fireworks, but the obscure metal has helped two University of Chicago scientists propose a theory of how the moon may have formed.

Conducted in the lab of Prof. Nicolas Dauphas, whose pioneering research studies the isotopic makeup of rocks from Earth and the moon, the new study measured rubidium in both planetary bodies and created a new model to explain the differences. The breakthrough reveals new insights into a conundrum about the moon's formation that has gripped the field of lunar science over the past decade, known as the "lunar isotopic crisis."

This crisis kicked off when new methods of testing revealed Earth and moon rocks have strikingly similar levels of some isotopes, but very different levels of others. This confounds both major scenarios for how the moon formed: one being that a giant object smashed into Earth and took a chunk with it on its way to becoming the moon (in which case the moon should have a decisively different makeup, mostly the foreign object); and the other being that this object obliterated the Earth, and the two celestial bodies eventually formed out of the resulting smithereens (in which case the two makeups should be virtually identical).

"There's clearly something missing there," said Nicole Nie, first author of the study, recently published in Astrophysical Journal Letters. A former graduate student in Dauphas' lab, Nie is now at the Carnegie Institution for Science.

To test different theories, Dauphas' lab has a collection of moon rocks on loan from NASA, (representing every Apollo mission that recovered samples). Nie came up with a rigorous way to measure the isotopes of rubidium—an element that had never been precisely measured in moon rocks because it's so difficult to isolate from potassium, which is chemically extremely similar.

Rubidium is one of a family of elements that consistently shows up with different proportions of isotopes in the moon compared to the Earth. When Nie examined the moon rocks, she found they did in fact contain fewer of rubidium's light isotopes and more heavy ones than Earth rocks do.

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"There was really no framework for how this difference happened," Dauphas said, a professor in the Department of Geophysical Sciences. "So we decided to make one."

They started from the idea that both the Earth and the giant object were vaporized after the impact. In this scenario, a mass that will become Earth slowly coalesces, and an outer ring of debris forms around it. It's still so hot, nearly 6,000 degrees Fahrenheit, that this ring is probably an airy outer layer of vapor surrounding a core of liquid magma.

Over time, Nie and Dauphas surmise, the lighter isotopes of elements like rubidium evaporate more readily. These condense onto the Earth, while the rest of the heavier isotopes left behind in the ring eventually form the moon.

This told them more about what the early moon and Earth would have looked like. Because they know exactly how much more of the lighter isotopes evaporated, they worked backward to find out how saturated the vapor layer would have been—the more saturated, the slower the evaporation. (Think of trying to dry out your laundry on a very humid day in the tropics, versus a dry day in the desert.)

This is helpful because exact characteristics of this early phase have been hard to pin down. The results also fit nicely with previous measurements of other isotopes in moon rocks, such as potassium, copper and zinc. "Our new scenario can quantitatively explain the lunar depletion of not only rubidium, but also most volatile elements," Nie said.

The study is a long-needed step to connect the lines between isotope measurements and physical models of the proto-planetary bodies, Dauphas said.

"This was a link that was missing, and we hope it will help to constrain the scenarios for early moon and Earth formation going forward," he said.

Explore further

Gallium in lunar samples explains loss of moon's easily vaporized elements

Source: Phys.org Return to Contents

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3. Beyond Jupiter, Researchers Discover a 'Cradle of Comets'

Comets are known to have a temper. As they swoop in from the outer edges of our solar system, these icy bodies begin spewing gas and dust as they venture closer to the Sun. Their luminous outbursts can result in spectacular sights that grace the night sky for days, weeks or even months.

But comets aren't born that way, and their pathway from their original formation location toward the inner solar system has been debated for a long time. Comets are of great interest to planetary scientists because they are likely to be the most pristine remnants of material left over from the birth of our solar system.

In a study published in The Astrophysical Journal Letters, a team of researchers including Kathryn Volk and Walter Harris at the University of Arizona Lunar and Planetary Laboratory report the discovery of an orbital region just beyond Jupiter that acts as a "comet gateway." This pathway funnels icy bodies called centaurs from the region of the giant planets -- Jupiter, Saturn, Uranus and Neptune -- into the inner solar system, where they can become regular visitors of Earth's neighborhood, cosmically speaking.

Roughly shaped like an imaginary donut encircling the area, the gateway was uncovered as part of a simulation of centaurs, small icy bodies traveling on chaotic orbits between Jupiter and Neptune.

Centaurs: Icy Rogues on Haphazard Trails

Centaurs are believed to originate in the Kuiper belt, a region populated by icy objects beyond Neptune and extending out to about 50 astronomical units, or 50 times the average distance between the Sun and the Earth. Close encounters with Neptune nudge some of them onto inward trajectories, and they become

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centaurs, which act as the source population of the roughly 1,000 short-period comets that zip around the inner solar system. These comets, also known as Jupiter-family comets, or JFCs, include comets visited by spacecraft missions such as Tempel 1 (Deep Impact), Wild 2 (Stardust) and 67P/Churyumov-Gerasimenko (Rosetta).

"The chaotic nature of their orbits obscures the exact pathways these centaurs follow on their way to becoming JFCs," said Volk, a co-author on the paper and an associate staff scientist who studies Kuiper belt objects, planetary dynamics and planets outside our solar system. "This makes it difficult to figure out where exactly they came from and where they might go in the future."

Jostled by the gravitational fields of several nearby giant planets -- Jupiter, Saturn and Neptune -- centaurs don't tend to stick around, making for a high-turnover neighborhood, Harris said. "They rattle around for a few million years, perhaps a few tens of millions of years, but none of them were there even close to the time when the solar system formed," he said. "We know of 300 centaurs that we can see through telescopes, but that's only the tip of an iceberg of an estimated 10 million such objects," Harris added.

"Most centaurs we know of weren't discovered until CCD's [digital imaging sensors] became available, plus you need the help of a computer to search for these objects," Volk said. "But there is a large bias in observations because the small objects simply aren't bright enough to be detected."

Where Comets Go to Die

Every pass around the Sun inflicts more wear and tear on a comet until it eventually breaks apart, has a close encounter with a planet that ejects it from the inner solar system, or its volatiles -- mostly gas and water -- are depleted. "Often, much of the dust remains and coats the surface, so the comet doesn't heat up much anymore and it goes dormant," Harris said.

By some mechanism, a steady supply of "baby comets" must replace those that have run their course, "but until now, we didn't know where they were coming from," he added.

To better understand how centaurs become JFCs, the research team focused on creating computer simulations that could reproduce the orbit of 29P/Schwassmann-Wachmann 1, or SW1, a centaur discovered in 1927 and thought to be about 40 miles across. SW1 has long puzzled astronomers with its high activity and frequent explosive outbursts despite the fact that is too far from the Sun for water ice to melt. Both its orbit and activity put SW1 in an evolutionary middle ground between the other centaurs and the JFCs, and the original goal of the investigation was to explore whether SW1's current circumstances were consistent with the orbital progression of the other centaurs.

To accomplish this, the team modeled the evolution of bodies from beyond Neptune's orbit, through the giant planet's region and inside Jupiter's orbit. "The results of our simulation included several findings that fundamentally alter our understanding of comet evolution," Harris said. "Of the new centaurs tracked by the simulation, more than one in five were found to enter an orbit similar to that of SW1 at some point in their evolution."

In other words, even though SW1 appears to be the only large centaur of the handful of objects currently known to occupy the "cradle of comets," it is not the outlier it was thought to be, but rather ordinary for a centaur, according to Harris.

In addition to the commonplace nature of SW1's orbit, the simulations led to an even more surprising discovery. "Centaurs passing through this region are the source of more than two-thirds of all Jupiter-family comets," Harris said, "making this the primary gateway through which these comets are produced."

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"Historically, our assumption has been that the region around Jupiter is fairly empty, cleaned out by the giant planet's gravity, but our results teach us that there is a region that is constantly being fed," Volk says.

This constant source of new objects may help explain the surprising rate of icy body impacts with Jupiter, such as the famous Shoemaker-Levy 9 event in 1994.

A Comet Worthy of Worship

Based on estimates and calculations of the number and size of objects entering, inhabiting and leaving the gateway region, the study predicted it should sustain an average population of about 1,000 Jupiter-family objects, not too far off the 500 that astronomers have found so far. The results also showed that the gateway region triggers a rapid transition: once a centaur has entered it, it is very likely to become a JFC within a few thousand years, a blink of an eye in solar system timeframes.

The calculations suggest that an object of SW1's size should enter the region every 50,000 years, making it likely that SW1 is the largest centaur to begin this transition in all of recorded human history, Harris and Volk suggest. In fact, SW1 could be on its way to becoming a "super comet" within a few thousand years.

Comparable in size and activity to comet Hale-Bopp, one of the brightest comets of the 20th century, SW1 has a 70% chance of becoming what could potentially amount to the most spectacular comet humankind has ever seen, the authors suggest.

"Our descendants could be seeing a comet 10 to 100 times more active than the famous Halley comet," Harris said, "except SW1 would be returning every six to 10 years instead of every 75." "If there had been a comet this bright in the last 10,000 years we would know about it," Volk said.

"We take this as strong evidence that a similar event has not happened at least since then," Harris said, "because ancient civilizations would not only have recorded the comet, they may have worshiped it!"

Reference: "29P/Schwassmann-Wachmann 1, A Centaur in the Gateway to the Jupiter-Family Comets," G. Sarid et al., 2019 Sep. 23, Astrophysical Journal Letters [https://iopscience.iop.org/article/10.3847/2041-8213/ab3fb3, preprint: https://arxiv.org/abs/1908.04185]. The study was co-authored by Gal Sarid and Maria Womack, both of the Florida Space Institute and the University of Central Florida; Jordan Steckloff of the Planetary Science Institute and the University of Texas at Austin; and Laura Woodney of California State University.

Source: Spaceref.com Return to Contents

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The Night Sky Friday, Oct. 25

• The Ghost of Summer Suns. Halloween is approaching, and this means that Arcturus, the star sparkling low in the west-northwest in evening twilight, has taken on its role as "the Ghost of Summer Suns." For several days centered on October 25th every year, Arcturus occupies a special place above your local landscape. It closely marks the spot where the Sun stood at the same time, by the clock, during hot June and July — in broad daylight, of course!

So, as Halloween approaches every year, you can see Arcturus as the chilly ghost of the departed summer Sun.

Saturday, Oct. 26

• The W of Cassiopeia now stands vertically on end in the evening, high in the northeast.

Look to its right, high in the east, for Andromeda and the corner-balanced Great Square of Pegasus.

Sunday, Oct. 27

• Spot bright Altair high in the southwest soon after dark. Brighter Vega is far to its right.

Two distinctive little constellations lurk above Altair: Delphinus the Dolphin, hardly more than a fist at arm's length to its upper left, and smaller, fainter Sagitta the Arrow, slightly less far to Altair's upper right. Light pollution too bright? Use binoculars!

• New Moon (exact at 11:38 p.m. Eastern Daylight Time).

Monday, Oct. 28

• It's getting to be the time of year when the Big Dipper lies down horizontal low in the north-northwest in the evening. How low? The farther south you are, the lower. Seen from 40° north (New York, Peoria, Denver) even its bottom stars twinkle nearly ten degrees high. But at Miami (26° N) the entire Dipper will skim along out of sight just below the northern horizon.

• Uranus is at opposition.

Source: Sky & Telescope Return to Contents

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ISS Sighting Opportunities

For Denver: Date Visible Max Height Appears Disappears Sat Oct 26, 4:58 AM < 1 min 16° 16° above ESE 14° above E Sat Oct 26, 6:31 AM 6 min 47° 12° above WSW 11° above NE Sun Oct 27, 5:45 AM 3 min 83° 72° above WSW 12° above NE Mon Oct 28, 4:59 AM < 1 min 18° 18° above ENE 12° above ENE Mon Oct 28, 6:32 AM 4 min 22° 16° above WNW 10° above NNE Tue Oct 29, 5:45 AM 2 min 30° 30° above N 11° above NE

Sighting information for other cities can be found at NASA’s Satellite Sighting Information NASA-TV Highlights (all times Eastern Daylight Time) No Special Programming

Watch NASA TV on the Net by going to the NASA website. Return to Contents

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Space Calendar • Oct 25 - Comet C/2019 D1 (Flewelling) At Opposition (1.727 AU) • Oct 25 - Asteroid 31801 (1999 LY26) Occults HIP 28686 (6.1 Magnitude Star) • Oct 25 - [Oct 21] Apollo Asteroid 2019 UQ Near-Earth Flyby (0.011 AU) • Oct 25 - [Oct 22] Apollo Asteroid 2019 UA2 Near-Earth Flyby (0.024 AU) • Oct 25 - Apollo Asteroid 2019 TQ2 Near-Earth Flyby (0.033 AU) • Oct 25 - Aten Asteroid 2017 TG5 Near-Earth Flyby (0.037 AU) • Oct 25 - Apollo Asteroid 162082 (1998 HL1) Near-Earth Flyby (0.042 AU) • Oct 25 - Kuiper Belt Object 308379 (2005 RS43) At Opposition (42.924 AU) • Oct 25 - Heinrich Schwabe's 230th Birthday (1789) • Oct 25-26 - Copernicus Hackathon and Climathon, Toulouse, France • Oct 26 - Comet P/2019 S3 (PANSTARRS) At Opposition (0.907 AU) • Oct 26 - Comet 383P/Christensen Perihelion (1.419 AU) • Oct 26 - Comet 76P/West-Kohoutek-Ikemura Perihelion (1.605 AU) • Oct 26 - [Oct 25] Aten Asteroid 2016 TH94 Near-Earth Flyby (0.028 AU) • Oct 26 - [Oct 22] Apollo Asteroid 2019 UD2 Near-Earth Flyby (0.031 AU) • Oct 26 - Apollo Asteroid 1863 Antinous Closest Approach To Earth (1.522 AU) • Oct 26 - Centaur Object 2015 JH1 At Opposition (8.248 AU) • Oct 26 - 15th Anniversary (2004), Cassini, 1st Targeted Titan Flyby • Oct 27 - European Summer Time Ends - Set Clock Back 1 Hour (European Union) • Oct 27 - Uranus At Opposition • Oct 27 - [Oct 22] Amor Asteroid 2019 UC2 Near-Earth Flyby (0.042 AU) • Oct 27 - Asteroid 3353 Jarvis Closest Approach To Earth (0.959 AU) • Oct 27 - Asteroid 797 Montana Closest Approach To Earth (1.687 AU) • Oct 27 - Asteroid 3526 Jeffbell Closest Approach To Earth (1.861 AU) • Oct 27 - Asteroid 5760 Mittlefehldt Closest Approach To Earth (1.925 AU) • Oct 27 - Neptune Trojan 530664 (2011 SO277) At Opposition (29.519 AU) • Oct 28 - Comet P/2018 L1 (PANSTARRS) At Opposition (2.254 AU) • Oct 28 - [Oct 22] Apollo Asteroid 2019 UT1 Near-Earth Flyby (0.012 AU) • Oct 28 - [Oct 22] Apollo Asteroid 2019 UE1 Near-Earth Flyby (0.022 AU) • Oct 28 - Asteroid 128036 Rafaelnadal Closest Approach To Earth (1.830 AU) • Oct 28 - Centaur Object 20461 Dioretsa At Opposition (30.283 AU) • Oct 28 - 45th Anniverary (1974), Luna 23 Launch (USSR Moon Lander)

Samuel Heinrich Schwabe

Source: JPL Space Calendar Return to Contents

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Food for Thought

A NASA Panel Says We Don’t Need to be so Careful About Infecting Other Worlds

It’s time to update the rules. That’s the conclusion of a panel that examined NASA’s rules for planetary protection. It was smart, at the dawn of the space age, to think about how we might inadvertently pollute other worlds with Earthly microbes as we explore the Solar System. But now that we know a lot more than we did back then, the rules don’t fit.

The Planetary Protection Office (PPO) handles these rules and how they apply to spacecraft. Not just for NASA, but for other partner nations too. The Planetary Protection Independent Review Board (PPIRB) produced this new report. The PPIRB was chaired by Alan Stern, a well-known American planetary scientist, and the principal investigator for NASA’s New Horizons mission to Pluto.

Whenever humans send a spacecraft to another body, there’s a risk of contaminating that body with microbes from Earth. Eliminating or lowering that risk is the only way to guarantee integrity in the search for life. Great pains are taken to sterilize spacecraft, but the risk is never zero. Spacecraft are prepared in sterile clean rooms before launch, and back in the 1970s, the Viking landers were sterilized in huge ovens built just for that purpose.

Conversely, we need to protect Earth from any unwanted visitors that might come back to visit us on one of our spacecraft. It might sound like the stuff of science fiction, but since we don’t yet know what microbes might exist on Mars, Enceladus, or some other world, we have to protect against contaminating Earth.

The Office of Planetary Protection assists in the construction of sterile spacecraft, or what they call “low biological burden” spacecraft. They also help develop low-risk flight plans that help protect other bodies, and Earth as well. The OPP also helps develop workable space policy to meet their aims.

But is it really necessary?

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According to this new report, with more and more space exploration, and with more and more countries and commercial players involved, the old set of rules may need to be updated.

“The landscape for planetary protection is moving very fast. It’s exciting now that for the first time, many different players are able to contemplate missions of both commercial and scientific interest to bodies in our solar system,” said Thomas Zurbuchen, associate administrator for NASA’s Science Mission Directorate. “We want to be prepared in this new environment with thoughtful and practical policies that enable scientific discoveries and preserve the integrity of our planet and the places we’re visiting.”

Many of the standards were put in place during the ’60s and ’70s. Our knowledge of the Moon and Mars, the most frequently visited bodies, has grown since then. The entire lunar surface was initially classified as important to the study of the origins of life. But that hasn’t held up, and now not many scientists think of the Moon as very significant in that study. At least not all of it.

It’s possible that the lunar poles played a role in the history of life, because they have long-lived deposits of water. But according to the PPIRB, there’s no reason to think that the rest of the Moon does. According to them, different regions on the Moon should have different standards for protection.

The Moon, and the Lunar Gateway, are likely staging points for future missions to Mars. Is there some risk of cross-contamination between the two? What about when spacecraft return samples to Earth, as the Mars 2020 rover will?

The reality is that material from Mars has been carried to Earth in orders of magnitude greater than any sampling humans can ever do. There’s been a natural flow of Martian material to Earth over billions of years, as meteors strike Mars and send debris into space. Some of that debris has landed on Earth. The PPIRB said the overall risk of contaminating Earth with Martian material should be reviewed.

The PPIRB isn’t suggesting that all precautions should be removed. One of their recommendations is that a special facility be constructed to receive Martian samples. In their report, they call it the Mars Sample Return Facility (MSRF.) This is not only for scientific reasons, but also to assure people that appropriate precautions are being taken.

From the PPIRB report: “As the first restricted Earth return since Apollo, MSR will be a uniquely high profile mission. Significant effort is being put into the MSR architectures to ensure there will be no harmful interference with Earth’s biosphere. This includes NASA work (alongside international partners) to “break the chain of contact” with the Mars environment during sample collection procedures on Mars 2020, the Sample Retrieval Lander and return procedures with the Earth Return Orbiter.”

Part of the effort to update Planetary Protection rules is driven by practical reality. There will be more and more commercial activity in space, and those endeavours need effective and streamlined rules to operate with.

“Planetary science and planetary protection techniques have both changed rapidly in recent years, and both will likely continue to evolve rapidly,” Stern said in a press release. “Planetary protection guidelines and practices need to be updated to reflect our new knowledge and new technologies, and the emergence of new entities planning missions across the solar system. There is global interest in this topic, and we also need to address how new players, for example in the commercial sector, can be integrated into planetary protection.”

Recent events on Mars support the review of Planetary Protection rules. Right now, the MSL Curiosity rover is seven years into its mission. Its over-arching goal is to assess whether Mars ever had an environment that could’ve supported microbial life. It’s doing that by exploring Gale Crater, and slowly working its way up Mt. Sharp, or Aeolis Mons.

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Curiosity passed by some rocks with dark streaks on them, and Curiosity scientists pointed out that the streaks are likely water, maybe seasonal seeps. Some of the Curiosity team wanted to investigate these streaks. But the Planetary Protection office was concerned about the possibility of contaminating those seeps. Even though Curiosity was sterilized on Earth, with some parts being baked at 110 C for almost a week, the moving of a drill bit to the rover’s robotic arm after sterilization violated the Office of Planetary Protection’s protocols. Staff at the Jet Propulsion Laboratory responsible for MSL Curiosity were unhappy.

The ocean moons in our Solar System are also future targets in the search for life, especially Europa and Enceladus. What kinds of protection should they receive when our spacecraft visit them? The PPIRB report addressed that issue.

As the report says, “The fraction of terrestrial microorganisms in spacecraft bio-burdens that has the potential to survive and amplify in ocean worlds is likely to be extremely small.” The report goes on to say that there’s almost no possibility that any indigenous life on Enceladus, Europa, or even Titan, has the same origins as Earth life, and that there’s no way scientists wouldn’t tell them apart.

“Any such life would be readily distinguishable from terrestrial microorganisms using modern biochemical techniques. As a consequence of these findings, the current bioburden requirements for Europa and Enceladus missions (i.e., <1 viable microorganism) appear to be unnecessarily conservative.”

NASA has received the report from the PPIRB and intends to develop new protocols. It’s likely that the surface of Mars, and the Moon, will be divided into zones. Some will be considered more important in the search for life and stricter guidelines will be in place. Others will be less restrictive.

But there’s another angle in all of this. Since each mission to Mars has an inherent risk of contaminating that planet with Earthly microbes, shouldn’t we make sure we investigate potentially life-bearing zones sooner rather than later? If so, we’ll need updated protocols sooner than we might think.

More:

• Press Release: NASA’s Planetary Protection Review Addresses Changing Reality of Space Exploration • Report: NASA Planetary Protection Independent Review Board • NASA: Planetary Protection

Source: Universe Today Return to Contents

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Space Image of the Week

Night Sky Reflections from the World's Largest Mirror Explanation What's being reflected in the world's largest mirror? Stars, galaxies, and a planet. Many of these stars are confined to the grand arch that runs across the image, an arch that is the central plane of our home Milky Way Galaxy. Inside the arch is another galaxy -- the neighboring Large Magellanic Cloud (LMC). Stars that are individually visible include Antares on the far left and Sirius on the far right. The planet Jupiter shines brightly just below Antares. The featured picture is composed of 15 vertical frames taken consecutively over ten minutes from the Uyuni Salt Flat in Bolivia. Uyuni Salt Flat (Salar de Uyuni) is the largest salt flat on Earth and is so large and so extraordinarily flat that, after a rain, it can become the world's largest mirror -- spanning 130 kilometers. This expansive mirror was captured in early April reflecting each of the galaxies, stars, and planet mentioned above. Image Credit & Copyright: Jheison Huerta Source: APOD Return to Contents