Noiseka Coli

Rabu, 31 Juli 2019

Will Private Companies Beat NASA to the Moon? - Space.com

With private companies setting their sights on sending humans to the moon in the near future, it's possible that one could touch down on the lunar surface before NASA astronauts do.

But the resulting "public versus private" space race isn't one that NASA feels overly competitive about. The space agency's plans to reach the moon involve relying on private corporations rather than challenging them.

"The challenges differ for the public and private sector, though they all do come down to money," Wendy Whitman Cobb told Space.com by email. Whitman Cobb, an associate professor at the U.S. Air Force's School of Advanced Air and Space Studies, examines the institutional dynamics of the policymaking behind space exploration. She stressed that her views are her own and do not necessarily reflect those of the Air Force or Department of Defense.

"Technology is not a problem for either sector — the ability to get to the moon has existed since the 1960s," Whitman-Cobb said. "What is different is the will to do it."

A worldwide team

NASA's current lunar push kicked into high gear in December 2017, when President Donald Trump signed a space-policy directive to send humans to the moon and establish a sustainable presence there. Earlier this year, Vice President Mike Pence told NASA to put boots on the moon by 2024, rather than the previous goal of 2028.

NASA's Artemis program aims to reach that goal. (In Greek mythology, Artemis was the twin sister of Apollo and goddess of the moon.) The agency's Orion spacecraft will carry human explorers to the Gateway outpost, a small space station that NASA plans to start building in lunar orbit in the early 2020s. Landers will then carry astronauts from the Gateway to the lunar surface.

The space agency won't be hitting these goals on its own. "We're already partnering with our commercial partners to build these systems, and later on we'll continue to work with our international partners to build up the Gateway," Marshall Smith, director of the human lunar exploration program at NASA's headquarters in Washington, told Space.com by email.

The space agency is currently working with 11 companies on Gateway and its associated systems. In May 2019, NASA awarded a contract to Maxar Technologies to build, launch and demonstrate in space the first major Gateway piece — the Power and Propulsion Element. The space agency also announced then that it had signed contracts with three companies to carry experiments to the moon via small robotic landers (though one of those three recently dropped out).

In June, NASA asked industry to figure out ways to deliver cargo to the Gateway — much like the companies SpaceX and Northrop Grumman make robotic resupply runs to the International Space Station.

In addition to working with private companies, NASA is also cooperating with other countries on the Artemis program. "International partners are a vital part of our lunar plan and will contribute to the goal of creating a sustainable lunar presence by 2028," Smith said.

Private contenders

But private industry isn't solely focused on helping NASA make it to the moon. Companies like SpaceX and Blue Origin have stated their intentions to design their own lunar exploration programs.

Elon Musk's SpaceX is currently working on a 100-passenger vehicle called Starship, which the company envisions carrying people to the moon and Mars. Starship will be lofted off Earth's surface by a huge rocket called Super Heavy. SpaceX already has one Starship-Super Heavy passenger flight planned for 2023. The company hopes to begin commercial operations of the pair as early as 2021, most likely with commercial satellite launches.

Blue Origin, operated by Amazon founder Jeff Bezos, is working on a big lander called Blue Moon, which will deliver science instruments, lunar rovers and, eventually, astronauts to the lunar surface.

Bezos sees many potential customers for Blue Moon other than NASA. "People are very excited about this capability to soft-land their cargo, their rovers, their science experiments on the surface of the moon in a precise way," Bezos said at the lander's unveiling in May 2019. "There is no capability to do that today."

Then there's Florida-based company Moon Express, which is working to become the first private enterprise to reach the moon with robotic spacecraft systems. In 2016, it became the first company to receive U.S. government approval to send a robotic spacecraft to the lunar surface.

"Our vision is really to expand Earth's economic and social sphere to include the moon," Alain Berinstain, Moon Express' vice president of global development, said last year at a lunar-science workshop at NASA's Ames Research Center in California. "We see the moon as the Earth's eighth continent to explore and to also mine for resources, like we have with every other continent on Earth."

Pittsburgh-based Astrobotic planned to launch its Peregrine lander to the moon in 2019, but that date has since been since pushed back to 2020 or 2021. "We're really, at Astrobotic, trying to do this the right way, meaning that we're trying to be as technically rigorous as possible," Dan Hendrickson, vice president of business development at Astrobotic, said at a Washington Space Business Roundtable in February. "We're trying to be very upfront with the entire community about our current status."

As with NASA, private industry has sufficient access to the technology to get to the moon, Whitman Cobb said. "They also have to demonstrate that their systems are fundamentally safe and reliable in order to attract paying customers — they are a business, after all," she said.

Private companies also tend to have a leaner leadership structure than NASA's 60-year-old legacy brings with it. "NASA's bureaucracy has stagnated since the 1960s," Whitman Cobb said. That makes it "more difficult for NASA to contract, make changes and adapt to new circumstances."

On the other hand, private companies have demonstrated the ability to move through technology development at a rapid rate, incorporating design and technology changes "almost immediately," she said. That brings its own advantages.

To the moon — without NASA?

For NASA, a return to the moon may bring its own difficulties. After President Trump called for a return to the moon, the space agency developed a goal to arrive by 2028. Not content with a 10-year plan, the administration challenged NASA to get it done by 2024 — within President Trump's second term, should he win re-election. The agency has since ramped up its efforts (and has stressed that one of the 2024 moonwalkers will be a woman — the first to set foot on the lunar surface).

Trump is hardly the first U.S president to call for a return to the moon. In 1989, George H. W. Bush proposed an ambitious exploration plan calling for the construction of an Earth-orbiting space station, crewed lunar exploration and, eventually, crewed missions to Mars. According to NASA's History division, "White House and Congressional reaction to the NASA plan was hostile, primarily due to the cost estimate." Only a few years later, the Clinton Administration's 1996 National Space Policy removed human exploration from the national agenda.

In 2004, George W. Bush made another stab at a lunar program, with plans to put astronauts on the lunar surface as early as 2015 and no later than 2020. That plan was cancelled in 2010 when President Barack Obama decided to send astronauts to a near-Earth asteroid by 2025, to help prepare for eventual crewed journeys to Mars.

The shifting political winds may be the reason that Pence's challenge to return Americans to the moon stressed a 21st-century space race with Russia and China. But the idea of an international space race may have more to do with politics than facts.

"When the idea of a new space race is invoked, it's usually being done in a way to stoke political willingness to devote more money to space," Whitman Cobb said. There is no real evidence that either Russia or China has the ability to go to the moon in the near term, she added.

"On the other hand, if politicians and/or the public begin to be fearful of Russian or Chinese intentions, they might be more willing to spend money on Project Artemis to get Americans back to the moon by 2024," she said.

In the past, NASA may have been able to shift with the changing political landscape, but the addition of private lunar exploration may create a problem for the space agency.

"If private companies get to the moon first, it will likely cause an existential crisis for NASA," Whitman Cobb said.

"If private companies can do it, what do we need NASA for?" she added. "In other words, it will only matter who gets there first if NASA fails to get there."

Follow Nola on Facebook and on Twitter at @NolaTRedd. Follow us on Twitter @Spacedotcom and on Facebook.

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https://www.space.com/nasa-private-companies-moon-race.html

2019-07-31 14:00:00Z
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This Bizarre Ancient Sea Monster Looked Like the Millennium Falcon - Live Science

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This Bizarre Ancient Sea Monster Looked Like the Millennium Falcon Live Science

A long time ago, in a galaxy not at all far away, a carnivore with an uncanny resemblance to the Millennium Falcon from "Star Wars" scuttled through the seas.

https://www.livescience.com/66067-millennium-falcon-cambrian-predator.html

2019-07-31 11:21:00Z
CBMiSmh0dHBzOi8vd3d3LmxpdmVzY2llbmNlLmNvbS82NjA2Ny1taWxsZW5uaXVtLWZhbGNvbi1jYW1icmlhbi1wcmVkYXRvci5odG1s0gFKaHR0cHM6Ly9hbXAubGl2ZXNjaWVuY2UuY29tLzY2MDY3LW1pbGxlbm5pdW0tZmFsY29uLWNhbWJyaWFuLXByZWRhdG9yLmh0bWw

First pictures of enzyme that drives new class of antibiotics - Phys.org

Understanding how antibiotic scaffolds are constructed in nature can help scientists prospect for new classes of antibiotics through DNA sequencing and genome mining. Researchers have used this knowledge to help solve the X-ray crystal structure of the enzyme that makes obafluorin—a broad spectrum antibiotic agent made by a fluorescent strain of soil bacteria. The new work from Washington University in St. Louis and the University at Buffalo is published July 31 in the journal Nature Communications.

A multi-part enzyme called a nonribosomal peptide synthetase produces the highly reactive beta-lactone ring that is responsible for obafluorin's antimicrobial activity.

"Obafluorin has a novel structure compared to all FDA-approved antibiotics," said Timothy Wencewicz, assistant professor of chemistry in Arts & Sciences. "In the long term, we really need new structural classes of antibiotics that have never been contaminated by clinical resistance from established antibiotic classes."

These chemicals could be used as next-generation antibiotics for humans, or even to benefit the agriculture sector, Wencewicz noted—as researchers strive to engineer seed treatments and biopesticides to support plant systems capable of making enough food to feed the 9.6 billion people projected to live on this planet by 2050.

The new work provides a useful road map that shows how individual protein domains in the ObiF1 enzyme are stitched together in three-dimensional space. An enzyme's structure is fundamental to almost every function it performs.

"The solution of this structure expands on previous discoveries to provide views of the molecular interactions between catalytic domains in a brand new way," said Andrew M. Gulick, associate professor in the department of structural biology in the Jacobs School of Medicine and Biomedical Sciences at the University at Buffalo. "This is a brand new class of compounds, and we've never had the molecular vision to appreciate how they are produced."

A multi-part enzyme called a nonribosomal peptide synthetase produces the highly reactive beta-lactone ring that is responsible for obafluorin's antimicrobial activity. Understanding how antibiotic scaffolds are constructed in nature can help scientists prospect for new classes of antibiotics through DNA sequencing and genome mining. Credit: Timothy Wencewicz, Washington University in St. Louis

Pinning down a new antibiotic from nature

Obafluorin is made by a fluorescent strain of soil bacteria that forms biofilms on plant roots. Obafluorin was originally discovered in 1984, but it wasn't until 2017 that Wencewicz uncovered the genetic blueprint of the enzyme that makes the molecule's bio-active components. That discovery marked the first time that anyone had been able to pin down a beta-lactone forming enzyme from nature, and recreate it in the laboratory.

Like penicillin, obafluorin has a four-membered ring—sometimes called an enchanted ring. A four-membered ring puts strain on bond angles that carbon prefers to adopt. But because a four-member ring is unstable, these molecules are also short-lived and difficult to make. For example, it took years for chemists to learn how to synthesize penicillin from chemicals and then figure out how fungi make it. This ultimately led to the global production of penicillin by fermentation.

Researchers in the Wencewicz laboratory were able to fast-track the discovery process using genetics to zero in on the biosynthetic machinery that bacteria use to make obafluorin, and then to reconstruct that multi-step, enzyme-catalyzed process in the laboratory.

Captured 'in the act'

For their new work, Wencewicz and Gulick, along with postdoctoral researcher Dale F. Kreitler (UB) and graduate students Jason E. Schaffer and Erin M. Gemmell (Washington University), mapped the full-length nonribosomal peptide synthetase (NRPS) that makes the bio-active components of obafluorin.

Gulick is an expert in NRPS systems and has published many of the seminal crystal structures of core pieces of these enzymes, as well as structures for full-length systems such as the one presented in this work.

The result is a comprehensive, detailed molecular structure at 3 Angstrom resolution that allows one to identify the atoms in the protein chain, see their location and points of contact along the chain, and determine how the pieces are assembled to produce useful molecules from start to finish.

"We were able to catch some of the building blocks of the molecules captured inside some of the enzyme-active sites—in the act of doing the chemistry," Wencewicz said. "This helped us to connect small molecules to the protein, and fill in some of the mechanistic gaps in how the molecules are created."

This type of view is particularly important for the future goal of creating a chemical library, populated with related beta-lactone compounds that have been engineered for beneficial uses.

"We also got a very interesting glimpse at how the domains of the protein actually talk to each other," Wencewicz said. The crystal structures allowed them to see how key components of the enzyme dock to each other, and how molecules are efficiently moved through the entire NRPS assembly line.

One particular component—something called an MbtH-like protein, or MLP, because it was first identified in a related system to produce mycobactin in the bacteria that causes tuberculosis—was shown to play a critical role in facilitating protein-to-protein interactions between catalytic domains.

"Turns out, the (overall) protein suffers largely when you take away this very little protein that provides the critical handshake," he said. "It showed us once and for all that the coordination of these domains is absolutely critical to the function of making antibiotics with this enzyme."

Taken as a whole, the new paper is unique in its reach, the researchers said, presenting the X-ray crystal structure of the complete obafluorin-synthesizing enzyme ObiF1, probing the molecular mechanism for various key steps in the catalytic cycle, and establishing the conserved residues that enable formation of the reactive beta-lactone ring.

A key step in a long process

Finding an antibiotic from a source in nature is only a first step in a long process of drug development. With the structure and techniques reported in this new paper, it is now possible to quickly and easily create analogs of the natural product in the laboratory—to optimize its molecular properties and bioactivity.

Gulick and Wencewicz plan to continue to apply their knowledge of the obafluorin biosynthetic pathway to discover new beta-lactone natural products using genomic and biochemical approaches.

"Given the structural diversity of known beta-lactone natural products, we believe that novel beta-lactone synthases remain to be discovered," Wencewicz said.

Washington University has filed for a U.S. utility patent covering this technology.

Explore further

By copying bacterial enzymes, lab quickly learns to synthesize new class of antibiotic molecules cleanly, efficiently

More information: Nature Communications (2019). DOI: 10.1038/s41467-019-11383-7

Provided by Washington University in St. Louis

Citation: First pictures of enzyme that drives new class of antibiotics (2019, July 31) retrieved 31 July 2019 from https://phys.org/news/2019-07-pictures-enzyme-class-antibiotics.html

This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.

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https://phys.org/news/2019-07-pictures-enzyme-class-antibiotics.html

2019-07-31 09:00:02Z
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Roy Exum: Tonight! The Black Moon - The Chattanoogan

As a rule I am leery of any hocus-pocus that comes my way. When I was a teenager some of my crowd would go down to the Chickamauga National Battlefield to taunt a ghost known as “Green Eyes” and I would never go. I knew I’d be a lot better off not “stirring up any haints” and, while I’ll probably never know if that is true, I can say with certainty staying on my side of any ghosts has served me well. I won’t dare wake up a sleeping dog on purpose either. I knew a boy who got ‘good and bit’ one time when he was such a fool and I do have an aversion to dog bites.

By the time I got to be a senior in high school some long-legged girl told me “Green Eyes” was just a silly girl’s way of getting a boy off into the darkness to kiss. I didn’t bat an eye admitting I ain’t a good kisser when I’m scared and left it be. Yet I’ve always had a “weather eye” and I wouldn’t be right if I didn’t share that this is the night of The Black Moon.

* * *

FROM TIMEANDDATE.COM: “Some years have 13 Full Moons, which makes at least one of them a Blue Moon, as it doesn't quite fit in with the traditional Full Moon naming system. However, this is not the only definition of a Blue Moon … (PAY ATTENTION) … About every 19 years, there is no Full Moon in February. This is one of several definitions of the term Black Moon. The other definitions refer to a New Moon which does not fit in with the equinoxes or solstices, similar to a Blue Moon.”

* * *

You know you have heard from your elders, “Such-and-so will only happen once in a blue moon.” That’s because a Blue Moon comes around only once in every 29 months. But it is only once in every 19 years that the month of February will have no new moon.

AGAIN, FROM TIMEANDDATE.COM:

* -- There is no single accepted definition of a Black Moon. The term has been commonly used to refer to any of the following phenomena associated with the New Moon:

* -- Second New Moon in the same month: These Black Moons are the most common ones, and they occur about once every 29 months. Because of time zone differences, the month they happen in can vary, like the Black Moon in July 2019 (US) or August 2019 (UK).

* -- Third New Moon in a season of four New Moons: These Black Moons are a little rarer, and occur about once every 33 months. We divide a year into four seasons - spring, summer, fall (autumn), and winter. Usually, each season has three months and three New Moons. When a season has four New Moons, the third New Moon is called a Black Moon. This is the exact counterpart to the original definition of a Blue Moon, except that Blue Moons are Full Moons.

* -- No New Moon in February: About once every 19 years, there is no New Moon in February. This can only happen in February, as this is the only month which is shorter than a lunar month (lunation). When this occurs, both January and March have two New Moons, instead of just one, which is the norm. The next Black Moon by this definition will occur in 2033, while the last one was in 2014. Because of time zone differences, these Black Moons may not happen all over the world. For instance, there is a Black Moon in the most western parts of the US in February 2022, but not in Europe or Australia.

* -- No Full Moon in February: About once every 19 years, February does not have a Full Moon. Instead, there are two Full Moons in January and March, also known as a double Blue Moon. The next Black Moon by this definition will occur in 2037, while the last one was in 2018. Because of time zone differences, these Black Moons may not happen all over the world.

* * *

Now here’s where the goodie gets good. “Black Moons hold special significance to people who practice certain forms of Pagan religions and who believe certain actions become more potent when performed on the night of a Black Moon.”

Wanna’ make a baby? At exactly 11:11 p.m. tonight the sun, the moon, and planet Earth will be in perfect alignment. Again, the key word is “potent.”

* * *

"God said, 'Let there be lights in the expanse of the sky to separate day from night; they shall serve as signs for the set times - the days and the years; and they shall serve as lights in the expanse of the sky to shine upon the earth.' And it was so. God made the two great lights, the greater light to dominate the day and the lesser light to dominate the night, and the stars." – Genesis 1:14-16

These two great lights are the sun, and the moon, respectively. The word for 'set times' here is moedim (appointed times) which is the very word that Yahweh chooses to use to describe His festivals. One more passage that speaks of these two lights is found in Psalms 104:19: "He made the moon to mark the seasons; the sun knows when to set."

* * *

WICCAN: THE SOLITARY BLACK MOON RITUAL

(From the website, sacredwicca.com, by Rowan Morgana, 2010)

On the night of the Dark Moon, as late as you can possibly stay awake, stand outside and breathe in the blackness of the night. It is Hecate’s night, the Crone Goddess has covered you in her blanket and given you the time to consider all those things in your life that you no longer need. You are safe within the womb of the Dark Goddess.

Consider that which you wish to banish from your life. Take your time, allow Hecate to guide your thoughts.

When you are ready, and you feel that you know exactly what must be banished turn widdershins to the East. Feel Hecate cleanse your mind of all unhealthy thoughts.

Turn widdershins to the North, feel Hecate cleanse your body of all unhealthy energies.

Turn widdershins to the West, feel Hecate cleanse your emotions of all that is causing you pain.

Turn widdershins to the South, feel Hecate cleanse your Spirit of all that is hindering your spiritual growth.

Breathe in the darkness of the night, breathe in the regenerative power of the Dark Goddess Hecate. Know that you are cleansed and purified, ready to begin mental, physical, emotional and spiritual growth with the coming of the New Moon.

It is done. So mote it be.

* * *

LILITH, THE QUEEN OF THE BLACK MOON?

Ancient Demon, Dark Deity, or Sensual Goddess? (From the website, Ancient-origins.org)

In some sources she's described as a demon, in others she is an icon who became one of the darkest deities of the pagans. Lilith is one of the oldest known female spirits of the world. Her roots come from the famous Epic of Gilgamesh, but she was also described in the Bible and the Talmud.

In Jewish tradition, she is the most notorious demon, but in some other sources she appears as the first woman created on Earth. According to a legend, God formed Lilith as the first woman. He did it in the same way as he created Adam. The only difference was that in place of pure dust, he also used filth and residue. Traditionally Lilith means ''the night'', and she is related to attributes connected with the spiritual aspects of sensuality and freedom, but also terror.

Lilith’s name comes from the Sumerian word ''lilitu'', which meant a wind spirit or a female demon. Lilith was mentioned in the Tablet XII of the Epic of Gilgamesh, a famous poem of ancient Mesopotamia dated back to not later than c. 2100 BC. The tablet was added to the original text much later, c. 600 BC, in its later Assyrian and Akkadian translations. She appears in a magical story, where she represents the branches of a tree.

She is described with other demons, but researchers still argue if she was a demon or a dark goddess. At the same time, she appeared in early Jewish sources, so it is difficult to find out who mentioned her first. However, it is obvious that from the beginning of her existence in the texts she was related to Sumerian witchcraft.

In the Babylonian Talmud, Lilith was described as a dark spirit with an uncontrollable and dangerous sexuality. She is said to have fertilized herself with male sperm to create demons. She is believed to be the mother of hundreds of demons.

Lilith appears in the Bible, in the Book of Isaiah 34:14, which describes the desolation of Eden. From the beginning, she is considered as a devilish spirit, unclean, and dangerous. The Genesis Rabbah describes her as the first wife of Adam. According to the book, God created her and Adam at the same time. Lilith was very strong, independent, and wanted to be equal with Adam. She did not accept being less important than him and refused to lie beneath Adam for copulation. The marriage did not work and they never found happiness.

As Robert Graves and Raphael Patai wrote in the book ‘The Hebrew Myths’:

''Adam complained to God: 'I have been deserted by my help meet' God at once sent the angels Senoy, Sansenoy and Semangelof to fetch Lilith back. They found her beside the Red Sea, a region abounding in lascivious demons, to whom she bore lilim at the rate of more than one hundred a day. 'Return to Adam without delay,' the angels said, `or we will drown you!'

Lilith asked: `How can I return to Adam and live like an honest housewife, after my stay beside the Red Sea?? 'It will be death to refuse!' they answered. `How can I die,' Lilith asked again, `when God has ordered me to take charge of all newborn children: boys up to the eighth day of life, that of circumcision; girls up to the twentieth day. None the less, if ever I see your three names or likenesses displayed in an amulet above a newborn child, I promise to spare it.' To this they agreed; but God punished Lilith by making one hundred of her demon children perish daily; and if she could not destroy a human infant, because of the angelic amulet, she would spitefully turn against her own.''

Due to the misunderstandings and disappointments related to Lilith, God decided to create a second wife for Adam– Eve.

- - -

Nowadays, Lilith has become a symbol of freedom for many feminist groups. Due to the rising level of education, women started to understand that they could be independent, so they began looking for symbols of feminine power. She also started to be worshiped by some followers of the pagan Wicca religion, which was created in the 1950s.

This appeal was enhanced by artists, who took her on as a muse. She started to be a popular motif in art and literature around the Renaissance period, when Michelangelo portrayed her as a half woman, half serpent being. He presented her around the Tree of Knowledge, and increased the importance of her legend. With time, Lilith became more attractive for the imaginations of male artists like Dante Gabriel Rosetti, who created her image as the most beautiful female being of the world. The author of ''The Chronicles of Narnia'', C.S. Lewis, was inspired by the legend about Lilith in the creation of the White Witch. She was beautiful, but dangerous and cruel.

* * *

Whatever! Just know that tonight, at 11:11 p.m., you might want to buy a lottery ticket.

royexum@aol.com

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https://www.chattanoogan.com/2019/7/31/393872/Roy-Exum-Tonight-The-Black-Moon.aspx

2019-07-31 03:39:19Z
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Selasa, 30 Juli 2019

Epic 'Terminator' Events Could Result in Gargantuan Solar Tsunamis, New Studies Suggest - Live Science

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Epic 'Terminator' Events Could Result in Gargantuan Solar Tsunamis, New Studies Suggest Live Science
Sun's Puzzling Plasma Recreated in a Laboratory Quanta Magazine
Scientists build a 'mini-sun' at a university campus to study solar wind CNET
Lab-made "Mini-Sun" sheds light on the real thing New Atlas
Scientists Built a Tiny Version of the Sun in Wisconsin VICE
View full coverage on Google News

https://www.livescience.com/66055-terminator-creates-solar-tsunamis.html

2019-07-30 10:48:00Z
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TESS hits the trifecta: Nearby bright star has 3 interesting planets - Ars Technica

Image of the TESS satellite with the Earth in the background. — Enlarge
NASA's Goddard Space Flight Center

Thanks to the massive trove of exoplanets discovered by the Kepler mission, we now have a good idea of what kinds of planets are out there, where they orbit, and how common the different types are. What we lack is a good sense of what that implies in terms of the conditions on the planets themselves. Kepler can tell us how big a planet is, but it doesn't know what the planet is made of. And planets in the "habitable zone" could be subjected to anything from a blazing hell to a frozen rock.

The Transiting Exoplanet Survey Satellite (or TESS) was launched with the intention of helping us figure out what exoplanets are actually like. TESS is designed to identify planets orbiting bright stars relatively close to Earth, conditions that should allow follow-up observations to figure out their compositions and potentially those of their atmospheres.

Right now, there's a conference happening that's dedicated to describing some of the first discoveries made using TESS. Those discoveries include a three-planet system that seems perfectly positioned to test all of our exoplanet characterization techniques.

What are we looking at?

Both Kepler and TESS identify planets using what's called the transit method. This works for systems in which the planets orbit in a plane that takes them between their host star and Earth. As this occurs, the planet blocks a small fraction of the starlight that we see from Earth (or nearby orbits). If these dips in light occur with regularity, they're diagnostic of something orbiting the star.

This tells us something about the planet. The frequency of the dips in the star's light tells us how long an orbit takes, which tells us how far the planet is from its host star. That, combined with the brightness of the host star, tells us how much incoming light the planet receives, which will influence its temperature. (The range of distances at which temperatures are consistent with liquid water is called the habitable zone.) And we can use that, along with how much light is being blocked, to figure out how big the planet is.

Enlarge / Details of the TESS hardware.
NASA GSFC

But this leaves a lot of important questions unanswered.

Take a planet that appears to be larger than Earth. It could be rocky, like Earth, placing it in the super-Earth category. But it could also have a dense core surrounded by a thick, gaseous atmosphere, making it a mini-Neptune. Or it could be water-dominated, making for a water- or ice-giant, depending on where it orbits.

That last issue isn't as clear as it seems, either. The temperature of a planet depends in part on its distance from its host star (as well as that star's brightness). Some of that light will be reflected by the planet's surface and any clouds present in its atmosphere. And a fraction of the energy that's absorbed by the planet will be trapped in the atmosphere by greenhouse gasses (including, yes, carbon dioxide).

So the planet's composition and its atmosphere's contents play huge roles in influencing its temperature. At a given distance from a star, it's often possible for these factors to make the difference between a frozen body and one that's hot enough to boil off its oceans.

So, to really understand other planets and their potential to support life, we have to understand what they're made of and what their atmosphere looks like. And, while TESS itself doesn't answer those questions, it's designed to find planets where other instruments could.

Finding things to look at

Fortunately, there are ways of figuring these things out. For example, knowing the size of a planet and its mass tells us its density, which in turn lets us make inferences about its composition. One option is to figure out how much a planet tugs on its host star as it moves about in its orbit. This tugging creates small Doppler shifts in the light coming from the star. This shift allows us to figure out the force the planet is exerting on the star, and thus its mass.

Alternately, if planets' orbits are packed tightly enough, they exert gravitational influences on each other: they speed up or slow down each other's orbits. These transit-timing variations can be registered over time and plugged into models that will provide plausible estimates for the planets' mass.

The transit method also has the potential to give us a sense of what's in the planet's atmosphere. As it passes in front of its host star, a small percentage of the starlight will be absorbed by the gasses in its atmosphere, creating a signature that can reveal the identity of those gasses. While this tiny signal is swamped by the noise in a single transit, observing multiple transits can eventually overcome this limitation.

All of this, however, requires a fair bit of light to start with, which means a bright, relatively nearby star. And we'd need to image multiple orbits, which means the planet in question needs to be orbiting relatively close to its host star.

These are precisely the things TESS is designed to pick up.

The new system

The new three-planet system is called TOI-270, and it's about 75 light years from Earth. The star at the center of the system is a red dwarf, a bit less than half the size of the Sun. Despite its small size, it's brighter than most of the nearby stars we know hosts planets. And—critically—it's stable. That means that variations in the star's light are minimal, and they're less likely to get in the way of trying to pick up subtle changes caused by its orbiting planets.

The three planets have orbital periods of 3.4 days, 5.7 days, and 11.4 days. The ratio among these periods can be expressed as ratios of integers, a feature that's called "orbital resonance."

These resonances tend to stabilize the orbits, keeping the planets' interactions from ejecting one of them from the system or send one diving into the star. Based on the size of the planets, the trio consists of a super Earth as the innermost planet, while the two outer planets are somewhat larger, falling into the class termed sub-Neptunes.

Right now, we only have enough observations of the TOI-270 system to confirm the existence of the three planets. Orbital simulations, however, suggest that a wide range of orbital eccentricities would be stable in the system, so it will take extended observations to figure out the precise details of the orbits.

But, since the longest orbit is under 12 days, that's not so onerous. Once the orbits are figured out, the planets are close enough together to cause transit-timing variations, providing us one avenue toward getting the masses of the planets. They're also large enough and close to the star to drag it around a bit while they orbit, creating Doppler shifts that would allow an independent measurement of the mass.

Significant atmospheres

The outer two planets, which are expected to have significant atmospheres, are prime candidates for studies of their composition. The authors estimate that the James Webb Space Telescope will eventually have a view of the system for over half the year, and it should be able to pick out the atmospheric signals for both planets.

What are we likely to find? All three planets are extremely hot, with only the outermost planet potentially being able to support some liquid water. However, it's also at the edge of boiling off any water into the atmosphere; the authors suggest temperate conditions are more likely on any moons it has. The interactions among the three planets also mean that each is likely to be tidally locked to the host star, which can result in a frigid far side of the planet and a baking star-facing side.

But even if habitability isn't an issue here, the system is definitely worth a careful look. When we have the sort of telescope hardware that will let us detect atmospheres, we'll want to test it out on something where it's likely to work and where we can troubleshoot the inevitable problems that will occur with the analysis. There will also be a learning process with the giant telescopes and James Webb that will be necessary for this work. That makes TOI-270 an important discovery, since it provides the perfect test conditions for exoplanet characterization.

Nature Astronomy, 2019. DOI: 10.1038/s41550-019-0845-5 (About DOIs).

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https://arstechnica.com/science/2019/07/tess-mission-finds-nearby-3-planet-system-thats-a-perfect-planet-lab/

2019-07-30 10:45:00Z
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When a Mega-Tsunami Drowned Mars, This Spot May Have Been Ground Zero - The New York Times

Today, Mars is a cold, dry world, home to dust devils and robotic explorers. But many scientists suspect it was once waterlogged.

A new study, published last month in the Journal of Geophysical Research: Planets, suggests that a 75-mile-wide impact scar in the Martian northern lowlands is to the red planet what the Chicxulub crater is to Earth: the mark of a meteor that generated a mega-tsunami when the planet was relatively young. If accurate, the finding adds evidence to the hypothesis that Mars once had an ocean, and would have implications for our search for life there.

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Whether Mars was ever warm and wet enough to retain a long-lived liquid water ocean has long been debated by planetary scientists. Several climate models have indicated that it was probably too cold. But other researchers point to ancient river deltas and other geological evidence of a northern ocean some 3.7 billion years ago.

Additional evidence includes hints of mangled, buried coastlines visible from orbit; these suggest that mega-tsunamis with skyscraper-high waves inundated parts of Mars’s northern shores around three billion years ago. On a world believed to have lacked Earthlike plate tectonics, any tsunamis were probably triggered by a meteor slamming into a huge body of water.

The area where the northern ocean was thought to exist also contains what are called thumbprint terrains, found on the landward side of those suspected ancient shorelines. These terrains may have been etched by the chaotic and violent flow of water in the aftermath of the mega-tsunamis. But which craters were tied to the impacts responsible for those mega-tsunamis was long a mystery.

In 2017, a team led by François Costard, a planetary geomorphologist at the French National Center for Scientific Research, used computer modeling to reproduce the mega-tsunamis most likely to have created those thumbprint terrains. That narrowed it down to a handful of impact craters.

For the new paper, Dr. Costard and his colleagues examined these candidate craters and ultimately zeroed in on Lomonosov, which was likely forged by a 9-by-12 mile meteor in just the right place at just the right time.

Scientists believe Mars’s Lomonosov Crater, which is about 75 miles wide, might be the site of the impact that caused a mega-tsunami. — CreditJPL/NASA

Its rim is also roughly the same height as the estimated depth of the ocean. Crucially, it physically resembles Earth’s marine craters, suggesting — if not definitively demonstrating — that it was created in a shallow ocean.

Another clue is the hole in the crater’s southern section. The plains there are tilted up toward the southern highlands. It’s possible that the ocean, displaced by the impact, would have rushed back most aggressively from this direction, bursting through the crater’s southern rim.

Alexis Rodriguez, a Mars geomorphologist at the Planetary Science Institute in Tucson, Ariz. and co-author of the new study, say the remnants of this Martian ocean may be a good target in the search for evidence of life on the red planet.

The ocean may have been fed by catastrophic floods from underground caches of liquid water. If so, sediments in the north “may be a window into the subsurface habitability of Mars,” Dr. Rodriguez said. If they contain geochemical signatures of ancient microbiology, then the liquid aquifers thought to exist beneath Mars’ surface may still be reservoirs for life today.

Of course, all this depends on whether a northern ocean actually existed — a conclusion challenged by studies of the red planet’s ancient climate. Dr. Rodriguez calls this one of the “core paradoxes” of Martian planetary science.

Paul Byrne, a planetary geologist at North Carolina State University who was not involved with the study, agreed: “It’s fair to say that we don’t yet fully understand the history of Mars’s climate, and certainly, the climate models we use will continue to be improved.”

Despite compelling geological evidence, he said, scientists still don’t have unambiguous proof of a northern ocean. “So the climate models might not be wrong,” he added — but more data is needed to say one way or the other.

Earlier reporting on Mars and water

NASA Mars 2020 Rover Gets a Landing Site: A Crater That Contained a Lake

Nov 19, 2018

A Large Body of Water on Mars Is Detected, Raising the Potential for Alien Life

Jul 25, 2018

Mega-Tsunamis Wiped Away Shoreline of a Martian Ocean

May 19, 2016

Mars Shows Signs of Having Flowing Water, Possible Niches for Life, NASA Says

Sep 28, 2015

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https://www.nytimes.com/2019/07/30/science/mars-tsunami-crater.html

2019-07-30 09:00:34Z
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There's A Rocky Exoplanet Out There With Three Glowing Red Suns In Its Sky! - Mashable India

For years, astronomers have been on a lookout for Earth-like planets outside our solar system. NASA’s Transiting Exoplanet Survey Satellite (TESS) has been dedicatedly employed to search exoplanets to explore the possibility of finding life in deep space and also, learning the secrets of the evolution of the Milky Way.

NASA’s exoplanet specialist telescope has now hunted down a certain rocky exoplanet locked in a triple-star system approximately 22.5 light-years away from our planet. Being referred to as LTT 1445Ab, the exoplanet is orbiting the primary star of the three red dwarfs that make the system. Hence, if you’re standing on its surface, you can spot three suns in the sky, as per Jennifer Winters, astronomer at Harvard-Smithsonian Center for Astrophysics.

The planet-hunting telescope, particularly focusing on exoplanets that pass between Earth and their home star came across the exoplanet, detecting how it was blocking a small percentage of light of its star. The dimming of the planet, as a result, grasped the attention of scientists who observed tiny movements of the star. Scientists could, thus, place constraints on the size and mass of the planet as it pulled the star only slightly owing to its gravity.

About 1.35 times the size of the physical Earth, LTT 1445Ab packs up to 8.4 times Earth’s mass, a lot denser than our home planet. Chances of habitability on this rocky exoplanet are slim even though it falls into the category of Mars, Venus and Earth-like terrain. However, it sure witnesses some really stunning skies. Besides, the new exoplanet could have an atmosphere which keeps scientists charged up for taking a closer look.

Scientists believe that LTT 1445Ab could be an excellent candidate for testing detection tools that are used to look for biogases such as methane and carbon dioxide. The reason being its frequent transitions which will offer ample number of opportunities for scientists for observation. As per cosmic scales, the exoplanet is not very far away from us and is just optimally lit by its stars for a conducive survey. The study has been submitted to the Astronomical Journal and is available on arXiv.

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https://in.mashable.com/science/5291/theres-a-rocky-exoplanet-out-there-with-three-glowing-red-suns-in-its-sky

2019-07-30 08:57:00Z
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Two meteor showers converge Monday night for a sparkling show - New York Daily News

Unfortunately, our website is currently unavailable in most European countries. We are engaged on the issue and committed to looking at options that support our full range of digital offerings to the EU market. We continue to identify technical compliance solutions that will provide all readers with our award-winning journalism.

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2019-07-30 03:13:00Z
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Double meteor shower happening tonight - WKRN News 2

Posted: Jul 29, 2019 / 09:05 PM CDT / Updated: Jul 29, 2019 / 09:06 PM CDT

Look up! We are having a double meteor shower tonight. The Delta Aquarids and Alpha Capricornids will shine through the sky tonight. Saturn will also be visible. The shower peaks tonight with up to 20 meteors per hour possible.

However, this shower could be hard to see for some because of the rain showers and storms that are possible overnight.

The best way to see the meteors is to look southeast away from any lights which includes the moon. The good news is the moon is only 5.9% visible because it is a waning crescent which will increase your chances of seeing the meteors flying across the sky tonight.

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2019-07-30 02:05:00Z
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Senin, 29 Juli 2019

Making an Exact, Working Replica of the Apollo 11 Moon Camera - PetaPixel

Four years ago, I set what seemed like an impossible goal: to make a functional Apollo 11 camera by the 50th anniversary of the moon landing. It was a crazy idea, especially with how inexperienced I was with nearly every process that would be required to do so.

I would need to build a workshop and learn how to operate machines that can precisely remove metal as easily as they can imprecisely remove your arm. I would need to learn how to 3D model parts, create accurate technical drawings, repair and reassemble rare camera bodies and intricate lenses that have very little documentation. It would take many thousands of hours of research, practice and learning, and it wouldn’t be cheap.

So, why do it?

The answer is quick for any photographer or space nut: It’s a MOON camera! But for the perplexed majority, the answer went a bit like this: some people like to resurrect classic cars, I wanted to resurrect a classic camera, and the camera we sent to and left on the lunar surface on Apollo 11 is one of the most important photographic tools ever made, capturing a historic milestone for our species.

The images we brought back were iconic. They changed culture, inspired generations of inventors, scientists, and entrepreneurs to do great things.

I could write a book all the nerdy details that went into the making this thing (we’re currently working on a documentary) but for the sake of this article, here are the highlights.

Finding Accurate Reference Material

First, it’s slightly surprising how little information there is on the moon cameras and how many inaccuracies there are in what little comes up in a simple search, starting with what one actually looks like.

We left most them on the moon to save weight for moon rocks, returning only with the exposed 70mm film. Auction photos of “the only camera to come back from the moon” show it with an early shuttle-era film magazine, the wrong lens, all while another camera that came back on Apollo 14 is sitting at the Smithsonian with less contested documentation. The camera also subtly evolved over the seven Apollo missions. Where do you start?

Luckily, I had access to the most critical resource—one of the few, early Hasselblad Electric Data Cameras made for NASA in 1968—that I could carefully measure and examine. As it turns out, it takes a moon camera to make a moon camera.

Next, I had to locate high-resolution press photos of Neil and Buzz training, which showed the first iteration of the camera that flew with them to the lunar surface. The Smithsonian had a lot of material, including great photos of the film magazine they brought back.

Collecting original repair manuals and notes from Hasselblad technicians was also critical in understanding the fundamentals of how the cameras functioned, down to the purpose of every screw.

The Réseau Plate

The defining feature of the lunar surface camera was the Réseau plate, a thin sheet of glass with a grid of crosshairs that pressed against the film plane. When you took a photo of, say, a crater on the lunar surface, these little crosshairs would show up in the image to help scientists measure the scale and distance of that particular lunar geography. We call that process photogrammetry, and it’s much like how Face ID measures the craters on my face to unlock my iPhone.

Hasselblad, the Swedish manufacturer responsible for first miniaturizing this technology for NASA, had spent so much time and effort building a separate factory to produce moon cameras, they decided to make a few available for government projects and aerial photography in the early 1970’s. They were sold privately as “Metrik Kameras,” and because they shot 70mm film, they called them “MK-70.”

I was able to find an old government MK-70 in complete disrepair—with missing parts, chipping paint, non-functional motors coated in crystalized battery acid—and salvage what would have been extremely difficult to manufacture. Combined with a new body housing from another broken Hasselblad from 1965, a beater suddenly had a second chance at life as a moon camera. One that may have preceded it on the same production line.

Modifying the Lens

The hardest part of the entire process was modifying the 60mm lens that came with the MK-70. The moon lens had a beautiful, matte black finish with rings that clicked crisply as you pushed friendly little levers with your bulky space gloves.

My lens? Modern shiny black finish, no levers, and the aperture ring didn’t click:

Damn. If we’re going for hyper-accuracy, we need clicking!

That meant a whole new aperture ring needed to be made, with engraved aperture numbers accurately spaced and internal gearing to make it *click* when you moved it. If any one gear, number, or bearing were off by more than half a degree, the aperture setting would be inaccurate, and the part would be junk.

After four weeks of reverse-engineering other lenses and realizing my math teacher in high school was totally right about Pi, I was able to model the new part, and have three blanks made by a very generous local manufacturer; three chances to screw up the laser engraving, the five-hour manual machining process, and the bead blasted anodize finish.

Thankfully, I only screwed up two.

Those friendly little levers were relatively easy to 3D print and cast out of metal after that, and the entire modification process was non-destructive, which means I can reverse the changes in the future if I need to.

Locating “Space Lube”

A funny thing happens when you put common lens grease in a vacuum. It boils off and solidifies, becoming more like a glue after hazing your optics. In fact, keeping any complex moving part slippery in space is still a real challenge today, so of course there’s a wonderful document from NASA that focuses solely on space lube.

It was from this study that I was able to locate the kind of lubricant they used on the real space-faring cameras in the 1960’s.

Remaining Tasks

You know what’s crazy? Any part of this camera could be swapped on the real thing and it would both fit and function as it would on the surface of the moon. There’s still a long way to go, however, to make it the most accurate representation of what’s still sitting in the lunar dust in the Sea of Tranquility.

Most notably, there’s a detachable polarizing filter that needs to be manufactured from scratch, a feature I believe to be unique to Apollo 11. Amazingly, my lens still has the hole for where it was attached.

The internal motor that drives the camera was also unique, using redundant switches to improve reliability, and an extra capacitor that reduced noise. Theoretically, the cameras should even sound the same after this modification.

And of course, the entire body has to be painted silver and labels applied. Hasselblad used a high-heat aluminum paint, the same you’d find on grills and car engines, for protection as the camera moved across the 400°F delta between light and shadow.

People Smarter than Me

Finally, as with any large undertaking, I had a ton of outside help on this project.

David Fred, who made satellite parts before teaching me what a water jet and a CNC mill could do to metal, was instrumental throughout the entire build process. The curator at the Smithsonian, the world’s leading expert on space cameras, found the very specific Apollo 11 serial numbers. Hasselblad let me handle some of their original cameras, Brennan Letkeman taught me the basics of 3D modeling, and every episode of Adam Savage’s “One-Day Builds” instilled a deep love for making that pushed me to believe this project was even possible.

This camera was the hardest thing I’ve ever done, and a journey that continues as more parts come in. But it was a worthwhile endeavor for the sake of the camera’s legacy, and in the spirit of doing things not because they’re easy, but because they’re hard.

About the author: Cole Rise is a photographer, pilot, and space camera maker currently based in Asheville, North Carolina. You can find his photographic work on his website and Instagram. You can learn more about his space camera work and forthcoming documentary here.

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2019-07-29 15:41:00Z
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Ro5 researchers suggest radioactive readings in 2017 were from a major nuclear release - Phys.org

A very large team of researchers from across Europe has found evidence that suggests radioactive ruthenium readings across the continent in 2017 were from an unknown nuclear source. In their paper published in Proceedings of the National Academy of Sciences, the group describes their study of the unusual readings two years ago and what they found.

Back in the 1960s, scientists around the world began to see the need to detect radiation from human sources as a means of alerting the public to possible health hazards. After the Chernobyl accident in 1986, scientists in Europe realized that a network of radiation monitoring stations was the best way to detect and alert the public to fallout from nuclear accidents. Scientists in five countries, Finland, Sweden, the Federal Republic of Germany, Denmark and Norway, set up such a network, which they called the Ro5. Scientists from other European countries have joined the network over the years, but the name has remained. Two years ago, members of the network began reporting higher-than-normal levels of ruthenium 106 (106Ru). The levels were not high enough to be considered dangerous, but the area of detection was large enough to suggest something unusual had happened—some suspected a nuclear accident at a facility in Russia. But Russian officials insisted the levels were due to a release from a disintegrating satellite. In this new effort, 69 researchers from across Europe together found evidence that very strongly suggests the radioactivity they observed came from a Russian nuclear power plant in a southern part of the Urals—likely Majak.

Research by the team consisted of combining and compiling 1,100 atmospheric readings and 200 readings taken on the ground. The researchers were able to conclude that the radioactivity was not from a satellite. They further report that levels of radioactivity varied widely, from tenths of µBq·m⁻³ to over 150 mBq·m⁻³. They also found that the widespread nature of the readings suggested an unprecedented release of 106Ru. By looking at the data placed over a map, they were able to trace it back to its source—in the Southern Urals in Russia. The researchers suggest the evidence indicates that there was likely an unreported nuclear plant accident.

Explore further

Russia named as likely source of Europe radioactivity spike (Update)

More information: O. Masson et al. Airborne concentrations and chemical considerations of radioactive ruthenium from an undeclared major nuclear release in 2017, Proceedings of the National Academy of Sciences (2019). DOI: 10.1073/pnas.1907571116

Citation: Ro5 researchers suggest radioactive readings in 2017 were from a major nuclear release (2019, July 29) retrieved 29 July 2019 from https://phys.org/news/2019-07-ro5-radioactive-major-nuclear.html

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2019-07-29 13:00:02Z
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Bringing Pieces of Mars to Earth in 2031: How NASA and Europe Plan to Do It - Space.com

Pristine samples of the Red Planet will come down to Earth a little over a decade from now, if everything goes according to plan.

NASA and the European Space Agency (ESA) are working together on a highly anticipated Mars sample-return mission, which advocates say is the logical next step in our study of the Red Planet and its life-hosting potential.

"We need to bring [Martian] materials back and bring them into our laboratories," Brian Muirhead, of NASA's Jet Propulsion Laboratory in Pasadena, California, said during a presentation with NASA's Future In-Space Operations (FISO) working group last month.

Scientists in labs around the world will be able to analyze such samples much more precisely, and in many more ways, than a rover could do by itself on the Red Planet, helping us "to understand the history of Mars from a biological point of view," added Muirhead, who leads NASA's Mars sample-return campaign.

Researchers could even find signs of life in these Mars rocks, which are scheduled to return to Earth in 2031.

The NASA-ESA plan is not yet official, Muirhead stressed, and details are still being worked out. But here's a rundown of the concept, as it's currently conceived.

A sample-snagging rover

The campaign begins next July, with the launch of NASA's car-size Mars 2020 rover. The six-wheeled robot is scheduled to touch down in February 2021 inside the 30-mile-wide (50 kilometers) Jezero Crater, which hosted a river delta in the ancient past.

Mars 2020 (which will soon get a catchier moniker, via a student naming competition) will characterize Jezero's geology, hunt for signs of ancient life, demonstrate various technologies that could enable future human exploration of the Red Planet and perform a variety of other work, including the collection and caching of samples.

The rover carries 43 tubes for this purpose, five of which will be "references" that help researchers understand the environment the other tubes have been through, Muirhead said. So Mars 2020 could snag a maximum of 38 samples. Ideally, the rover will drop some of these in an accessible spot and keep others on its body, he added.

The next big step comes in 2026, with the launch of NASA's Sample Retrieval Lander (SRL) mission. SRL will include a stationary lander, the ESA-provided Sample Fetch Rover (SFR) and a rocket called the Mars Ascent Vehicle (MAV), which will be no more than 10 feet (3 meters) tall, Muirhead said.

The mission will touch down near the Mars 2020 landing site, and then SFR will hit the red dirt. This little robot will be smaller than NASA's golf-cart-size Spirit and Opportunity rovers, and it will leverage technology developed for ESA's life-hunting ExoMars rover, which is scheduled to launch toward the Red Planet next summer, just a week after Mars 2020 does.

The SFR will carry no science instruments, Muirhead said. Its lone job, as its name indicates, will be to get the samples dropped by Mars 2020 back to the lander, where they will be placed into the basketball-size Orbiting Sample container, or OS. (The sample-return campaign is complex, so it's even heavier on the acronyms than most space missions are.) If Mars 2020 does indeed hold on to some of its collected samples, this bigger rover could roll over to the lander as well.

"We've had to design the lander to accommodate both of these rovers coming and delivering tubes to us," Muirhead said.

Launching off the Martian surface

An overview of the planned NASA-ESA Mars sample-return campaign.

All of this will take time. The SRL surface mission is expected to last about eight months, with five months devoted to fetching, Muirhead said. Meanwhile, the MAV will be sitting there, waiting for its moment.

"It's got to survive the surface environment — mostly [low] temperature, but dust also," Muirhead said. "And then it's got to launch and deliver into Mars orbit. So, it's a challenging environment for rocket propulsion."

Spacecraft have launched from the surface of Earth's moon before — the Apollo missions did this multiple times — but no vehicle has ever left the much more massive Mars after landing there. So the MAV will make exploration history.

The MAV's specs have yet to be firmed up, Muirhead said. The sample-return team is looking at two options: a two-stage solid-propellant version, and a single-stage rocket that employs hybrid propulsion technology. A decision on the design should come by the end of the year, Muirhead said.

After taking the OS on board, the MAV will launch off the solar-powered lander and deploy the OS container into Mars orbit, at least 190 miles (300 km) above the planet's surface. It will be plucked out of the void by the third big piece of this grand plan: ESA's Earth Return Orbiter (ERO).

Bringing it all back home

Like the SRL mission, ERO is scheduled to launch in 2026. ESA recently invited European companies to submit proposals to build the spacecraft.

"The mission is becoming a reality, and we are proud to give European industry the chance to join the challenge," ESA's Orson Sutherland, study manager for ERO, said in a statement.

The ERO will use electric propulsion and feature multistage detachable modules, leveraging technologies developed for the recently launched BepiColombo mission to Mercury, ESA officials said.

The European orbiter will install the newly captured OS inside a sterile containment system and then sterilize the joints of that system, likely using heat, Muirhead said. Such protocols will ensure that no Mars material leaks out during entry to Earth's atmosphere, potentially contaminating our planet.

The containment system will be placed inside a special entry vehicle, which will deploy from the ERO when the spacecraft nears Earth. The entry vehicle will barrel through our planet's atmosphere and slam into a playa, or dry lake bed, in Utah.

The team has designed the entry vehicle to operate without parachutes, relying instead on completely passive technologies. This strategy takes one big potential failure point out of play, Muirhead said.

The entry vehicle will experience impact forces of about 1,000 Gs if it hits the playa dirt, and perhaps 3,000 Gs if it's unlucky enough to slam into a rock, Muirhead said. (The acceleration at Earth's surface due to our planet's gravity is 1 G.)

"We're designing to both of those [scenarios]," he added.

The targeted landing date is 2031. Mars and Earth align favorably for interplanetary launches just once every 26 months. So, if the SRL and ERO aren't ready in 2026, the next opportunity would come in 2028, with a 2033 sample return to Earth.

"But beyond that, we really lose opportunities to do MSR [Mars sample return]," Muirhead said. "This is really a good opportunity, and we're working very hard to make this opportunity pay off."

Waiting for approval

Again, the campaign outlined above is just a concept at the moment. Though the 2020 federal budget request allocates some money to NASA for MSR development, the project is not officially on NASA's books yet, or those of ESA.

So we don't know how much all of this would cost. Muirhead said the team is treating the campaign as cost-constrained with a hard cap, though it's unclear what that cap will be.

MSR will be tough to pull off, requiring "multiple missions that will be more challenging and more advanced than any robotic missions before," ESA officials said in a different statement.

But the team thinks it's up to the challenge.

"The campaign and the design studies that we've been conducting with ESA are proceeding extremely well," Muirhead said. "We are prepared to proceed with this partnership to implement the objectives, pending approval from our respective funding agencies."

Mike Wall's book about the search for alien life, "Out There" (Grand Central Publishing, 2018; illustrated by Karl Tate), is out now. Follow him on Twitter @michaeldwall. Follow us on Twitter @Spacedotcom or Facebook.

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2019-07-29 11:00:00Z
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