And if you’re interested in looking back, here’s an archive to all the past Carnivals of Space. If you’ve got a space-related blog, you should really join the carnival. Just email an entry to [email protected], and the next host will link to it. It will help get awareness out there about your writing, help you meet others in the space community – and community is what blogging is all about. And if you really want to help out, sign up to be a host. Send an email to the above address.
Scientists were able to gauge the rate of water loss on Mars by measuring the ratio of water and HDO from today and 4.3 billion years ago. Credit: Kevin Gill
It is a scientific fact that water exists on Mars. Though most of it today consists of water ice in the polar regions or in subsurface areas near the temperate zones, the presence of H²O has been confirmed many times over. It is evidenced by the sculpted channels and outflows that still mark the surface, as well as the presence of clay and mineral deposits that could only have been formed by water. Recent geological surveys provide more evidence that Mars’ surface was once home to warm, flowing water billions of years ago.
But where did the water go? And how and when did it disappear exactly? As it turns out, the answers may lie here on Earth, thanks to meteorites from Mars that indicate that it may have a global reservoir of ice that lies beneath the surface.
Together, researchers from the Tokyo Institute of Technology, the Lunar and Planetary Institute in Houston, the Carnegie Institution for Science in Washington and NASA’s Astromaterials Research and Exploration Science Division examined three Martian meteorites. What they found were samples of water that contained hydrogen atoms that had a ratio of isotopes distinct from that found in water in Mars’ mantle and atmosphere.
Mudstone formations in the Gale Crater show the flat bedding of sediments deposited at the bottom of a lakebed. Credit: NASA/JPL-Caltech/MSSS
This new study examined meteors obtained from different periods in Mars’ past. What the researchers found seemed to indicate that water-ice may have existed beneath the crust intact over long periods of time.
As Professor Tomohiro told Universe Today via email, the significance of this find is that “the new hydrogen reservoir (ground ice and/or hydrated crust) potentially accounts for the “missing” surface water on Mars.”
Basically, there is a gap between what is thought to have existed in the past, and what is observed today in the form of water ice. The findings made by Tomohiro and the international research team help to account for this.
“The total inventory of “observable” current surface water (that mostly occurs as polar ice, ~10E6 km3) is more than one order magnitude smaller than the estimated volume of ancient surface water (~10E7 to 10E8 km3) that is thought to have covered the northern lowlands,” said Tomohiro. “The lack of water at the surface today was problematic for advocates of such large paleo-ocean and -lake volume.”
Meteorites from Mars, like NWA 7034 (shown here), contain evidence of Mars’ watery past. Credit: NASA
In their investigation, the researchers compared the water, hydrogen isotopes and other volatile elements within the meteorites. The results of these examinations forced them to consider two possibilities: In one, the newly identified hydrogen reservoir is evidence of a near-surface ice interbedded with sediment. The second possibility, which seemed far more likely, was that they came from hydrated rock that exists near the top of the Martian crust.
“The evidence is the ‘non-atmospheric’ hydrogen isotope composition of this reservoir,” Tomohiro said. “If this reservoir occurs near the surface, it should easily interact with the atmosphere, resulting in “isotopic equilibrium”. The non-atmospheric signature indicates that this reservoir must be sequestered elsewhere of this red planet, i.e. ground-ice.”
While the issue of the “missing Martian water” remains controversial, this study may help to bridge the gap between Mars supposed warm, wet past and its cold and icy present. Along with other studies performed here on Earth – as well as the massive amounts of data being transmitted from the many rover and orbiters operating on and in orbit of the planet – are helping to pave the way towards a manned mission, which NASA plans to mount by 2030.
The team’s findings are reported in the journal Earth and Planetary Science Letters.
I need to get something off my chest. A month or so ago I was sitting in a classroom surrounded by 10 peers. For the first time this semester we had the opportunity to spend the entire day discussing astronomy. And I was thrilled to dive into that brilliant subject, which I have adored for most of my 26 years.
But it didn’t take long before the day turned sour. Most of my classmates touched on one common theme: why should we care about astronomy when it has no practical applications? It’s a concern I have seen time and time again from students, museum guests, and readers alike.
So dear world, here is why you should care.
It’s true that astronomy has few practical applications and yet somehow its advances benefit millions of people across the world.
Just as astronomy struggles to see increasingly faint objects, medicine struggles to see things obscured within the human body. So astronomy has developed technology used in CAT scanners and MRIs. It has also developed technology now used by FedEx to track packages, GPS satellites to determine your location, apple to develop a camera for your iPhone, to name a few.
But all of these are mere second thoughts, benefits that have occurred without the primary intention of the maker. And that is what makes astronomy beautiful. To study something — not because we’re looking to gain anything in particular, but out of sheer curiosity — is what makes us human.
Doing things for their own sake creates room for mindfulness and joy. Aristotle makes this point in his Nicomachean Ethics. He says: “the work is the maker in actuality; so he loves his work, because he loves his existence too. And this is a fact of nature; for what he is in potentiality, the work shows in actuality.”
Work itself is inherently valuable and it is somehow connected to our very existence. It stands alone and not as a path toward a paycheck or a practical application. Countless studies show just this. In one famous example, psychologists Edward Deci and Richard Ryan, both from the University of Rochester, asked two groups of college students to work on various puzzles. One group was paid for each puzzle it solved. The other group wasn’t.
Deci and Ryan found that the group that was paid to solve puzzles quit the second the experiment was over. The other group, however, found the puzzles intrinsically fascinating, and continued to solve the puzzles well after finishing the experiment. The second group found joy in the puzzles even when — and perhaps because — there was no monetary value to gain. There’s mindfulness in the act of work itself.
Then there is the sheer joy of looking up. On the darkest of nights, far from the city lights, thousands of stars are sprinkled from horizon to horizon. We now know there are over one billion stars in our galaxy and over one billion galaxies in our universe. It fills me with such wonder and humility to know our small place in the vast cosmos above us.
I firmly believe that astronomy has a spiritual dimension, maybe not in the sense of a supreme being, but in the sense of how it connects us with something bigger than ourselves. It brings us closer to nature by illuminating the ongoing mysteries in the universe.
Because of astronomy we now know that the Universe sparked into existence 13.7 billion years ago. We’ve spotted shining pinpricks of light in the early universe and know them to be supermassive black holes, with such strong gravitational fields, that matter is raining down onto them. We’ve seen distant galaxies colliding in a swirl of stars, gas and dust. And we’ve spotted thousands of planets orbiting other stars.
We’ve glimpsed the wonders of the universe — both big and small — for others to appreciate. So while astronomy doesn’t set out with the intention of changing our lives on a practical level, it does change our lives. It has explained mysteries that have confounded us for thousands of years, but more crucially, it has opened up more mysteries than any of us can study in our lifetime.
I have to wonder: what human being isn’t compelled to study a discipline that sparks such curiosity and joy?
We hear that rocks are a certain age, and stars are another age. And the Universe itself is 13.7 billion years old. But how do astronomers figure this out?
I know it’s impolite to ask, but, how old are you? And how do you know? And doesn’t comparing your drivers license to your beautiful and informative “Year In Space” calendar feel somewhat arbitrary? How do we know old how everything is when what we observe was around long before calendars, or the Earth, or even the stars?
Scientists have pondered about the age of things since the beginning of science. When did that rock formation appear? When did that dinosaur die? How long has the Earth been around? When did the Moon form? What about the Universe? How long has that party been going on? Can I drink this beer yet, or will I go blind? How long can Spam remain edible past its expiration date?
As with distance, scientists have developed a range of tools to measure the age of stuff in the Universe. From rocks, to stars, to the Universe itself. Just like distance, it works like a ladder, where certain tools work for the youngest objects, and other tools take over for middle aged stuff, and other tools help to date the most ancient.
Let’s start with the things you can actually get your hands on, like plants, rocks, dinosaur bones and meteorites. Scientists use a technique known as radiometric dating. The nuclear age taught us how to blow up stuff real good, but it also helped understand how elements transform from one element to another through radioactive decay.
For example, there’s a version of carbon, called carbon-14. If you started with a kilo of it, after about 5,730 years, half of it would have turned into carbon-12. And then by 5,730 more years, you’d have about ¼ carbon-14 and ¾ carbon-12.
A list of the elements with their corresponding visible light emission spectra. Image Credit: MIT Wavelength Tables, NIST Atomic Spectrum Database, umop.net
This is known as an element’s half-life. And so, if you measure the ratio of carbon-12 to carbon-14 in a dead tree, for example, you can calculate how long ago it lived. Different elements work for different ages. Carbon-14 works for the last 50,000 years or so, while Uranium-238 has a half-life of 4.5 billion years, and will let you date the most ancient of rocks. But what about the stuff we can’t touch, like stars?
When you use a telescope to view a star, you can break up its light into different colors, like a rainbow. This is known as a star’s spectra, and if you look carefully, you can see black lines, or gaps, which correspond to certain elements. Since they can measure the ratios of different elements, astronomers can just look at a star to see how old it is. They can measure the ratio of uranium-238 to lead-206, and know how long that star has been around. How astronomers know the age of the Universe itself is one of my favorites, and we did a whole episode on this.
Artist’s conception of Planck, a space observatory operated by the European Space Agency, and the cosmic microwave background. Credit: ESA and the Planck Collaboration – D. Ducros
The short answer is, they measure the wavelength of the Cosmic Microwave Background Radiation. Since they know this used to be visible light, and has been stretched out by the expansion of the Universe, they can extrapolate back from its current wavelength to what it was at the beginning of the Universe. This tells them the age is about 13.8 billion years. Radiometric dating was a revolution for science. It finally gave us a dependable method to calculate the age of anything and everything, and finally figure out how long everything has been around.
So, fan of our videos. How old are you? Tell us in the comments below.
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Taking the Chinese Yutu rover out for a spin on the Moon. The mission began in December 2013. Credit: Chinese Academy of Sciences
It’s been just over a year since China wowed the world with the first soft Moon landing in almost 40 years. The Chang’e-3 robotic lander made it all the way to Mare Imbrium (Sea of Rains) on Dec. 14, 2013, quickly deploying the Yutu rover for a spin.
Mission updates have been sparse in recent months, but the Planetary Society and a forum on Unmanned Spaceflight recently pointed out a new image archive. These pictures are so high-definition, it’s almost as good as being on the Moon beside the rover.
While some of the images are familiar to followers of the mission, what makes the image archive stick out is how high-definition many of them are.
China’s Yutu rover scoots around on the Moon in this undated photo. The mission began in December 2013. Credit: Chinese Academy of Sciences
A few great shots have been sent back from the surface, including a set from January that was combined into a 360-degree panorama by Marco Di Lorenzo and Universe Today’s Ken Kremer. But this archive contains a wealth of them.
The lander/rover team made it to the surface last year equipped with high-definition video cameras, prepared to catch some of the first new views of the lunar surface from close up since the Apollo robotic/human and Soviet robotic moon landing era of the 1960s and 1970s.
Chang’e-3 viewed from the Yutu lunar rover. The mission began in December 2013. Credit: Chinese Academy of Sciences
Shortly before Yutu entered a planned hibernation for its second lunar night (about two weeks on Earth) in January, a technical problem was reported that was later identified as a problem with its solar panel.
A “control circuit malfunction”, according to the Xinhua news agency, left the rover at risk of not waking up after that second hibernation. The mast it controlled was supposed to lower and protect some of the rover’s sensitive electronics. Yutu survived the night, but was left unable to move through the third lunar day.
According to the Planetary Society (based on Chinese news media reports), there are no current status updates for Yutu, but Chang’e-3 is still working a year after the landing.
The Yutu rover leaves the Chang’e-3 lunar lander in December 2013. Credit: Chinese Academy of SciencesThe Chang’e-3 mission’s view of lunar rocks. The mission began in December 2013. Credit: Chinese Academy of Sciences
This Chandra image of the Tycho supernova remnant contains new evidence for what triggered the original supernova explosion. Credit: NASA/CXC/Chinese Academy of Sciences/F. Lu et al.
At one time or another, all science enthusiasts have heard the late Carl Sagan’s infamous words: “We are made of star stuff.” But what does that mean exactly? How could colossal balls of plasma, greedily burning away their nuclear fuel in faraway time and space, play any part in spawning the vast complexity of our Earthly world? How is it that “the nitrogen in our DNA, the calcium in our teeth, the iron in our blood, the carbon in our apple pies” could have been forged so offhandedly deep in the hearts of these massive stellar giants?
Unsurprisingly, the story is both elegant and profoundly awe-inspiring.
All stars come from humble beginnings: namely, a gigantic, rotating clump of gas and dust. Gravity drives the cloud to condense as it spins, swirling into an ever more tightly packed sphere of material. Eventually, the star-to-be becomes so dense and hot that molecules of hydrogen in its core collide and fuse into new molecules of helium. These nuclear reactions release powerful bursts of energy in the form of light. The gas shines brightly; a star is born.
The ultimate fate of our fledgling star depends on its mass. Smaller, lightweight stars burn though the hydrogen in their core more slowly than heavier stars, shining somewhat more dimly but living far longer lives. Over time, however, falling hydrogen levels at the center of the star cause fewer hydrogen fusion reactions; fewer hydrogen fusion reactions mean less energy, and therefore less outward pressure.
At a certain point, the star can no longer maintain the tension its core had been sustaining against the mass of its outer layers. Gravity tips the scale, and the outer layers begin to tumble inward on the core. But their collapse heats things up, increasing the core pressure and reversing the process once again. A new hydrogen burning shell is created just outside the core, reestablishing a buffer against the gravity of the star’s surface layers.
While the core continues conducting lower-energy helium fusion reactions, the force of the new hydrogen burning shell pushes on the star’s exterior, causing the outer layers to swell more and more. The star expands and cools into a red giant. Its outer layers will ultimately escape the pull of gravity altogether, floating off into space and leaving behind a small, dead core – a white dwarf.
Lower-mass stars like our sun eventually enter a swollen, red giant phase. Ultimately, its outer layers will be thrown off altogether, leaving nothing but a small white dwarf star. Image Credit: ESO/S. Steinhofel
Heavier stars also occasionally falter in the fight between pressure and gravity, creating new shells of atoms to fuse in the process; however, unlike smaller stars, their excess mass allows them to keep forming these layers. The result is a series of concentric spheres, each shell containing heavier elements than the one surrounding it. Hydrogen in the core gives rise to helium. Helium atoms fuse together to form carbon. Carbon combines with helium to create oxygen, which fuses into neon, then magnesium, then silicon… all the way across the periodic table to iron, where the chain ends. Such massive stars act like a furnace, driving these reactions by way of sheer available energy.
But this energy is a finite resource. Once the star’s core becomes a solid ball of iron, it can no longer fuse elements to create energy. As was the case for smaller stars, fewer energetic reactions in the core of heavyweight stars mean less outward pressure against the force of gravity. The outer layers of the star will then begin to collapse, hastening the pace of heavy element fusion and further reducing the amount of energy available to hold up those outer layers. Density increases exponentially in the shrinking core, jamming together protons and electrons so tightly that it becomes an entirely new entity: a neutron star.
At this point, the core cannot get any denser. The star’s massive outer shells – still tumbling inward and still chock-full of volatile elements – no longer have anywhere to go. They slam into the core like a speeding oil rig crashing into a brick wall, and erupt into a monstrous explosion: a supernova. The extraordinary energies generated during this blast finally allow the fusion of elements even heavier than iron, from cobalt all the way to uranium.
Periodic Table of Elements. Massive stars can fuse elements up to Iron (Fe), atomic number 26. Elements with atomic numbers 27 through 92 are produced in the aftermath of a massive star’s core collapse.
The energetic shock wave produced by the supernova moves out into the cosmos, disbursing heavy elements in its wake. These atoms can later be incorporated into planetary systems like our own. Given the right conditions – for instance, an appropriately stable star and a position within its Habitable Zone – these elements provide the building blocks for complex life.
Today, our everyday lives are made possible by these very atoms, forged long ago in the life and death throes of massive stars. Our ability to do anything at all – wake up from a deep sleep, enjoy a delicious meal, drive a car, write a sentence, add and subtract, solve a problem, call a friend, laugh, cry, sing, dance, run, jump, and play – is governed mostly by the behavior of tiny chains of hydrogen combined with heavier elements like carbon, nitrogen, oxygen, and phosphorus.
Other heavy elements are present in smaller quantities in the body, but are nonetheless just as vital to proper functioning. For instance, calcium, fluorine, magnesium, and silicon work alongside phosphorus to strengthen and grow our bones and teeth; ionized sodium, potassium, and chlorine play a vital role in maintaining the body’s fluid balance and electrical activity; and iron comprises the key portion of hemoglobin, the protein that equips our red blood cells with the ability to deliver the oxygen we inhale to the rest of our body.
So, the next time you are having a bad day, try this: close your eyes, take a deep breath, and contemplate the chain of events that connects your body and mind to a place billions of lightyears away, deep in the distant reaches of space and time. Recall that massive stars, many times larger than our sun, spent millions of years turning energy into matter, creating the atoms that make up every part of you, the Earth, and everyone you have ever known and loved.
We human beings are so small; and yet, the delicate dance of molecules made from this star stuff gives rise to a biology that enables us to ponder our wider Universe and how we came to exist at all. Carl Sagan himself explained it best: “Some part of our being knows this is where we came from. We long to return; and we can, because the cosmos is also within us. We’re made of star stuff. We are a way for the cosmos to know itself.”
A diver tests out a spacesuit in NASA's Neutral Buoyancy Laboratory in Houston in December 2014. Credit: Zugzwang5 (imgur)
If you’ve spent any length of time underwater, you appreciate just how much drag it creates on your limbs — especially if you’re wearing a little clothing or carrying around diving equipment. Now, try to imagine using a pressurized spacesuit in that environment. You’re already puffed up like a balloon and have the drag to contend with.
Few of us will get that experience — NASA won’t let just anybody try on an expensive suit — but luckily for us, a person saying he is a diver (identifying himself only as Zugzwang5) posted about the experience on Reddit. The pictures alone are incredible, but the insights the diver provides show just how tough an astronaut has to be to get ready for spacewalking.
Using the spacesuit compared to a wetsuit, wrote Zugzwang 5 on Reddit, was “incredibly cumbersome”. He says he’s a contracted diver for Oceaneering working at NASA’s Neutral Buoyancy Laboratory in Houston, which has a model of the International Space Station in a huge pool for astronauts to practice spacewalking. Usually he’s inside a wetsuit, but the spacesuit was a completely different experience, he said.
There’s so much resistance from the suit and the water every motion takes tremendous effort. You might not guess it from my pictures, but I’m actually pretty fit, and I was exhausted by the end of the day. The hardest thing to get used to was moving up and down in the water column. I’ve been diving so long controlling my buoyancy is basically a force of will at this point, having to actually crawl and direct myself up and down was such a weird feeling.
A diver at NASA’s Neutral Buoyancy Laboratory in Houston tries out a spacesuit during a practice dive in December 2014. Credit: Zugzwang 5/imgur
Near the end of the marathon session, the diver had to bring back a simulated “incapacitated” astronaut to the airlock underwater, which he wrote was an extremely difficult task — especially while so tired.
So, for a real astronaut to pass their final evaluation they have to do a flawless incapacitated crew member rescue. this is actually very difficult as safely manipulating another suit is even more tiring and cumbersome than just moving your own. not only that but the airlock is very small, and safely (using proper tether technique) hooking someone else up into it is a surprisingly complex procedure where you have zero extra space to work with. Thirty minutes usually ends up being hardly enough time for the new guys, and even a vet will take more than 20.
An artist concept of the view from an airship orbiting Venus. Credit: NASA Langley HAVOC team.
Venus presents a special challenge to space explorers. Yes, there is a surface, but hellish temperatures and atmospheric pressure on the surface of Venus has a tendency to crush spacecraft fairly quickly. Short of building a submarine-rated surface explorer, maybe there’s a better way to look at the hothouse planet? A newly proposed NASA concept suggests using airships. Yes, airships with people in them.
But as you will see below, balloons and airships have been discussed extensively in the past decade by NASA and the Europeans as the best way of exploring Venus without needing to touch its hellish surface.
Venus may seem nothing but a distraction to an agency that is talking about exploring Mars in the 2030s (with Orion’s recent uncrewed test being the first advertised step of that, although critics say it won’t get us to the Red Planet). Leaving that aside, however, exploring Venus by balloon is not a new idea at all, even within NASA. The backers of the High Altitude Venus Operational Concept (HAVOC) even argue we should head to Venus before Mars, as one of the co-leads recently told Universe Today.
“A human mission to Venus is not on a lot of people’s radar, but we’ve really enjoyed working on the concepts for this mission,” said Langley’s Chris Jones, project co-lead, in an interview with Universe Today’s Nancy Atkinson. “This was an internal study: what does the future of humankind in space look like? Frankly, we see Venus as potentially no later than the second planetary destination that humans might go to, after Mars or even before Mars.”
Artist’s conception of the High Altitude Venus Operational Concept (HAVOC) mission, a far-out concept being developed by NASA, approaching the planet. Credit: NASA Langley Research Center/YouTube (screenshot)
Why? Jones explained that because it takes a shorter time to get to Venus, that makes it a “stepping stone or practice run” to get humans to Mars. “The best would be a long lived surface lander, but technology issues for surface robotic missions are pretty significant, and a human mission to surface is nearly insurmountable. What’s left is a good platform for a science mission at mid-level altitudes, and it paints a good picture for a human mission in the atmosphere at 50 kilometers.”
The proposed flight profile of the HAVOC airship at Venus. Credit: Space Mission Analysis Branch, NASA Langley Research Center.
The clouds of Venus, Jones said, present an ideal spot for humans to roam from a spacecraft. The conditions at 50 kilometers (31 miles) above the surface are about the same pressure and atmosphere as Earth.
“Air itself is a lifting gas at those altitudes,” he added, “so you don’t have to bring some ridiculous supply of helium for this to work. And the rest of the environmental parameters at 50 kilometers are actually quite nice: the gravity is about the same as on Earth’s surface, the atmospheric pressure is about the same as Earth, and we can potentially manufacture a significant amount of that air by processing carbon dioxide. These are some of the facts we saw early on that inspired us to do this.”
There also would be more solar power and protection from radiation than Mars, and the temperature — although fairly hot — would be possible to account for fairly easily in spacecraft designs.
Jones provided some details on how the crew would spend about 30 days exploring the planet after a journey there and back (440 days total). Bear in mind that the mission is just in the early stages of even thinking about development. Cost, timeline, approvals and many other hurdles would need to be overcome before it could even become a reality.
Details of the proposed HAVOC airship mission to Venus. Credit: Space Mission Analysis Branch, NASA Langley Research Center.
“The big parameters of Venus’ atmosphere is the big longitudinal winds,” Jones said. “If you just rode them, it would take you about 110 hours to circle the planet. The other component of winds would push you towards the poles. In order to stay near the equator where there is less turbulence, the airship would ride the longitudinal winds while using a propulsion system to counter those winds pushing you towards the poles.”
The concept arose from science objectives for the planet out of NASA’s Venus Exploration Analysis Group, Jones said, whose aims include understanding the atmosphere and its interaction with the surface. NASA’s Langley Research Center also has human objectives they considered, such as showing how people can work in deep space and develop advanced technologies to accomplish that.
The proposed Venus exploration plan for HAVOC. Credit: Space Mission Analysis Branch, NASA Langley Research Center.
The HAVOC mission would start with a series of phased exploration sorties. The first phase would be examining the Venusian atmosphere with a robotic mission, and the second would be crewed ride to orbit that would include deploying an uncrewed robotic airship in the atmosphere.
The third phase is the 30-day mission described above, while the fourth phase could potentially be as long as a year. If it gets to a Phase 5, that would be a “permanent presence in Venus’ atmosphere”, Jones said.
A size comparison of ships for the proposed HAVOC mission to Venus. Credit: Space Mission Analysis Branch, NASA Langley Research Center.
Of note: balloons have been discussed before within NASA, particularly by Venus exploration advocate Geoffrey Landis of NASA Glenn, and Jones told Universe Today that this new team found much inspiration from Landis’ previous work.
Universe Today interviewed Landis in 2008 about missions he proposed about human-colony airships and uncrewed solar-powered airplanes. And in this 2010 study, he suggested three ideas for exploring the surface using uncrewed low-altitude balloons. One would skim the clouds around 25 kilometers (15.6 miles) and two other concepts (more rigid, naturally), would fly about 5 kilometers (3 miles) high. This was presented at an American Institute of Aeronautics and Astronautics meeting that year.
The remaining core of the High Altitude Venus Operational Concept (HAVOC), a far-out mission being developed by NASA, in this artist’s concept. Credit: NASA Langley Research Center/YouTube (screenshot)
“A notable advantage of the carbon dioxide atmosphere of Venus is that this allows a much wider range of lifting gasses for a balloon; not merely the hydrogen or helium usually used for terrestrial balloons,” Landis wrote in the paper. “Oxygen and nitrogen, in fact, are lifting gasses in the Venus atmosphere (although not good ones). At the altitudes considered, two other lifting gasses are water (which is a gas at the temperatures considered) and ammonia.”
Landis was also not deterred by harsh surface conditions. While Venus’ surface is difficult — its 480 Celsius (900 Fahrenheit) thick atmosphere destroyed the Soviet Venera probes in minutes — he’s secured early-stage NASA funding for a robotic landsailing rover concept nicknamed “Zephyr”. “Sailing on Venus! How cool is that? The project will have an exceptional public engagement factor,” the description page for the Venus Landsailing Rover reads.
In a nutshell, Glenn has created electronics that can continue to function in temperatures similar to what are found on the surface. Simulations also show that solar cells would work, albeit at reduced efficiency. Hence the idea to use a heavily-reinforced landsail to take advantage of Venus’ 100-times-more-pressure-than-Earth atmosphere at the surface. Wind speeds are less than a meter of second, but have terrific force behind them. And at least some of Venus appears to be flat, with rocks only a centimeter thick in pictures from Venera.
Artist’s concept for a landsail rover on Mars, based on an idea by NASA’s Geoffrey Landis. Credit: NASA
Balloons have also been considered by the European Space Agency, particularly in the form of an uncrewed Venus Entry Probe discussed in detail in this presentation by Surrey Satellite Technology Ltd. It would include a Low Venus Orbiter that would map the planet to complement closer-to-ground measurements, a Venus Relay Satellite that would send information from the balloon, and the “aerobot” itself.
“The aerobot consists of a long-duration balloon and gondola … that will analyze the Venusian middle cloud layer at an altitude of ~55 km, where the environment is relatively benign. The balloon will deploy a swarm of active ‘ballast’ micro-sondes, which, once deployed, will determine vertical profiles of the lower atmosphere,” the presentation reads. More detailed information is available from this 2004 ESA workshop presentation by Surrey and this ESA webpage, which says the study was completed in 2005.
Students have even explored Venusian balloon ideas, such as in the 2014 Summer School Alpbach cosponsored by the European Space Agency. An uncrewed idea called EvolVe suggests a joint orbiter and balloon mission to see how tectonic activity and volcanoes affected the surface of Venus, among other scientific goals. The balloon would hover in the same general region, about 50 to 60 km (31 miles to 37 miles), and probe the surface using radar and other tools. It’s one of two concepts selected for further investigation that could lead to a science conference presentation and/or science journal publication.
A mosaic of images of Comet 67P/Churyumov–Gerasimenko taken from the Rosetta spacecraft Dec. 14. Credit: ESA/Rosetta/NAVCAM – CC BY-SA IGO 3.0
Remember how breathless we felt when the Philae lander actually made it to the surface of its target comet a few weeks ago? Sure, the maneuvers didn’t go as planned, but the images the spacecraft obtained in its brief spurts of activity on the surface are still being shared and discussed eagerly by scientists (amid a controversial image release policy, to be sure.)
Well, the truck delivery for Philae — the Rosetta spacecraft, still doing maneuvers above — is going to do something special in February. The machine is going to scoot down real close to the comet, just before heating from the Sun could make it dangerous to do so due to gas and dust emissions.
The plan is to bring Rosetta to an astounding four miles (six kilometers) above Comet 67P/Churyumov–Gerasimenko, so close that the images sent back to Earth will have a resolution of just a few inches per pixel. Scientists hope to learn more about how reflective the comet is and also to better understand how gas is emitted as 67P draws close to the Sun.
A mosaic of images of Comet 67P/Churyumov–Gerasimenko taken from the Rosetta spacecraft Dec. 14. Credit: ESA/Rosetta/NAVCAM – CC BY-SA IGO 3.0
“As the comet becomes more and more active, it will not be possible to get so close to the comet. So this opportunity is very unique,” stated Matt Taylor, the Rosetta project scientist from the European Space Research and Technology Center, in a NASA press release.
Rosetta’s closest view of the comet previous to this was a six-mile (10 kilometer) mapping orbit that it did for a short time before moving to release the Philae lander. After that, its orbit was expected to range between 20 km and 50 km (12.4 miles and 18.6 miles) through the end of this month.
Philae, meanwhile, made it down to the surface and did manage to send pictures back during its approximately 60 hours of activity, before shutting down due to a lack of sunlight hitting its solar panels. Philae is now wedged in a shady spot on the comet, but it’s possible more sunlight could fall in that area when the comet nears its closest approach to the Sun in 2015, between the orbits of Earth and Mars.
The European Space Agency is saying that about 20% of the mission’s science is expected to flow from Philae (at most), and 80% from Rosetta. Early results from both spacecraft present some intriguing properties about the comet. Based on the ratio of isotopes (types) of hydrogen on the comet, it’s more likely that it was asteroids that delivered water to Earth. Also, Philae was unable to dig very far into the surface, implying that underneath the dust must be something like a thick layer of ice.
A recent Rosetta blog post on the European Space Agency says that the team expects to take a break for the holidays from posting — unless, of course, they manage to track down the Philae lander in pictures. The location of the spacecraft is still unknown, but it’s believed that Rosetta’s high-resolution camera may be able to catch the lander or its glint — coupled with clues Philae’s experiments gave to its location.
Expedition 42 astronaut Butch Wilmore holds up a 3-D-printed rachet, the first such tool made in space. Credit: NASA
In the 1960s, we thought the best way of sending stuff between Earth and space was through a transporter. These days, turns out all it takes is an e-mail and a special 3-D printer. The first tool created in space, a rachet, was made last week on the International Space Station using plans beamed from Earth. Now, we get to see if it actually works.
The printer has been active for a few weeks, making test items that had already been done on Earth. But for this particular item, manufacturer Made In Space chose to take an additional risk: creating a tool from plans that were done almost at the last minute, similar to how a real mission would work when astronauts have a sudden need for a part.
“Made In Space uplinked a design which did not exist when the printer was launched. In fact the ratchet was designed, qualified, tested, and printed in space in less than a week,” the company wrote on its blog.
NASA astronaut Butch Wilmore (Expedition 42 commander on the International Space Station) holds the first 3-D printed part made in space, which was created on Nov. 25, 2014. Credit: NASA
And it wasn’t as simple as just sending up the plans and hoping for the best. NASA had to give the safety thumbs-up before it went up there. Also, the plans (once sent to the space station) were verified as okay to go by Made In Space engineers before the crew got the okay to print last week.
The rachet took about four hours to print in space, which is a heck of a lot faster than sitting around waiting for a cargo ship — especially when said ship is delayed, as what happened recently to the SpaceX Dragon that was supposed to launch on Friday (Dec. 19) and has now been pushed back to at least Jan. 6.
While the rachet could be of use for simple repairs in space, it won’t be staying up there long. Just as with all the other parts printed so far, it’s going to be sent back to Earth for analysis to make sure it can stand up to the rigors of a space mission. Made In Space will soon have a more robust printer going up to station, and wants to make sure all the kinks are worked out before then.
