April 20, 2017April 28, 2017 by Evan Gough

The Bubbly Streams Of Titan

The appearing and disappearing feature observed in Titan's Lakes was dubbed "Magic Island". Image: NASA/JPL-Caltech/ASI/Cornell

Saturn’s largest Moon, Titan, is the only other world in our Solar System that has stable liquid on its surface. That alone, and the fact that the liquid is composed of methane, ethane, and nitrogen, makes it an object of fascination. The bright spot features that Cassini observed in the methane seas that dot the polar regions only deepen the fascination.

A new paper published in Nature Astronomy digs deeper into a phenomenon in Titan’s seas that has been puzzling scientists. In 2013, Cassini noticed a feature that wasn’t there on previous fly-bys of the same region. In subsequent images, the feature had disappeared again. What could it be?

One explanation is that the feature could be a disappearing island, rising and falling in the liquid. This idea took hold, but was only an initial guess. Adding to the mystery was the doubling in size of these potential islands. Others speculated that they could be waves, the first waves observed anywhere other than on Earth. Binding all of these together was the idea that the appearance and disappearance could be caused by seasonal changes on the moon.

Titan's dense, hydrocarbon rich atmosphere remains a focal point of scientific research. Credit: NASA — Titan’s dense, hydrocarbon rich atmosphere remains a focal point of scientific research. Credit: NASA

Now, scientists at NASA’s Jet Propulsion Laboratory (JPL) think they know what’s behind these so-called ‘disappearing islands,’ and it seems like they are related to seasonal changes.

The study was led by Michael Malaska of JPL. The researchers simulated the frigid conditions on Titan, where the temperature is -179.2 Celsius. At that temperature, some interesting things happen to the nitrogen in Titan’s atmosphere.

On Titan, it rains. But the rain is composed of extremely cold methane. As that methane falls to the surface, it absorbs significant amounts of nitrogen from the atmosphere. The rain hits Titan’s surface and collects in the lakes on the moon’s polar regions.

The researchers manipulated the conditions in their experiments to mirror the changes that occur on Titan. They changed the temperature, the pressure, and the methane/ethane composition. As they did so, they found that nitrogen bubbled out of solution.

“Our experiments showed that when methane-rich liquids mix with ethane-rich ones — for example from a heavy rain, or when runoff from a methane river mixes into an ethane-rich lake — the nitrogen is less able to stay in solution,” said Michael Malaska of JPL. This release of nitrogen is called exsolution. It can occur when the seasons change on Titan, and the seas of methane and ethane experience a slight warming.

“Thanks to this work on nitrogen’s solubility, we’re now confident that bubbles could indeed form in the seas, and in fact may be more abundant than we’d expected,” said Jason Hofgartner of JPL, a co-author of the study who also works on Cassini’s radar team. These nitrogen bubbles would be very reflective, which explains why Cassini was able to see them.

The first-ever images of the surface of a new moon or planet are always exciting. The Huygens probe was launched from Cassini to the surface of Titan, but was not able investigate the lakes and seas on the surface. Image Credit: ESA/NASA/JPL/University of Arizona

The seas on Titan may be what’s called a prebiotic environment, where chemical conditions are hospitable to the appearance of life. Some think that the seas may already be home to life, though there’s no evidence of this, and Cassini wasn’t equipped to investigate that premise. Some experiments have shown that an atmosphere like Titan’s could generate complex molecules, and even the building blocks of life.

NASA and others have talked about different ways to explore Titan, including balloons, a drone, splashdown landers, and even a submarine. The submarine idea even received a NASA grant in 2015, to develop the idea further.

So, mystery solved, probably. Titan’s bright spots are neither islands nor waves, but bubbles.

Cassini’s mission will end soon, and it’ll be quite some time before Titan can be investigated further. The question of whether Titan’s seas are hospitable to the formation of life, or whether there may already be life there, will have to wait. What role the nitrogen bubbles play in Titan’s life question will also have to wait.

April 19, 2017April 28, 2017 by Evan Gough

Art History NASA Style

This illustration of a double-cylinder space colony is from the 1970's, by artist Rick Guidice. Image: NASA Ames Research Center

To some, art and science are opposed to one another. Art is aesthetics, expression, and intuition, while science is all cold, hard, rational thought. But that’s a simplistic understanding. They’re both quintessential human endeavours, and they’re both part of the human spirit.

Some at NASA have always understood this, and there’s actually an interesting, collaborative history between NASA and the art world, that reaches back several decades. Not the kind of art that you see hanging in elite galleries in the world’s large cities, but the kind of art that documents achievements in space exploration, and that helps us envision what our future could be.

Mitchell Jamieson produced this painting of astronaut Gordon Cooper. Titled "First Steps", it documents Cooper's first steps after exiting his Mercury spacecraft in 1963, after Cooper had completed 22 orbits of Earth. Image Credit: Mitchell Jamieson/Courtesy of the Smithsonian National Air and Space Museum — Mitchell Jamieson produced this painting of astronaut Gordon Cooper. Titled “First Steps”, it documents Cooper’s first steps after exiting his Mercury spacecraft in 1963, after Cooper had completed 22 orbits of Earth. Image Credit: Mitchell Jamieson/Courtesy of the Smithsonian National Air and Space Museum

Back in 1962, when NASA was 4 years old, NASA administrator James Webb put the wheels in motion for a collaboration between NASA and American artists. Artist Bruce Stevenson had been commissioned to produce a portrait of Alan Shepard. Shepard, of course, was the first American in space. He piloted the first Project Mercury flight, MR-3, in 1961. When Webb saw it, he got a bright idea.

When Stevenson brought is portrait of Shepard to NASA headquarters, James Webb thought that Stevenson wanted to paint portraits of all seven Mercury astronauts. But Webb thought a group portrait would be even better. The group portrait was never produced, but it got Webb thinking. In a memo, he said “…we should consider in a deliberate way just what NASA should do in the field of fine arts to commemorate the …historic events” of the American space program.

That set in motion a framework that exists to this day. Beyond just portraits, Webb wanted artists to produce paintings that would convey the excitement around the entire endeavour of space flight, and what the deeper meaning behind it might be. He wanted artists to capture all of the excitement around the preparation and countdown for launches, and activities in space.

This 1963 painting by artist Paul Calle captures the lift-off of the Saturn V Moon rocket. Image: Paul Calle, NASA

That’s when the NASA collaboration with artists began. A young artist named James Dean was assigned to the program, and he took a page out of the Air Force’s book, which established its own art program in 1954.

There’s a whole cast of characters involved, each one contributing to the success of the program. One such person was John Walker, Director of the National Gallery. He was enthusiastic, saying in a talk in 1965 that “the present space exploration effort by the United States will probably rank among the more important events in the history of mankind.” History has certainly proven those words to be true.

This Norman Rockwell painting is from 1965, and shows astronauts Gus Grissom and John Young suiting up for the first Gemini flight in March, 1965. NASA loaned Rockwell a spacesuit for the painting. Image: Norman Rockwell, NASA Art Program

Walker went on to say that it was the artists’ job “…not only to record the physical appearance of the strange new world which space technology is creating, but to edit, select and probe for the inner meaning and emotional impact of events which may change the destiny of our race.”

And that’s what they did. Artists like Norman Rockwell, Andy Warhol, Peter Hurd, Annie Liebowitz, Robert Rauschenberg, and others, all took part in the program.

Artist Peter Hurd painted the launch of Skylab in 1973. Image Credit: Peter Hurd, Courtesy of National Air and Space Museum, Smithsonian Institution

In the 1970’s, thinkers like Gerard K. O’Neill began to formulate ideas of what human colonies in space might look like. NASA held a series of conferences where these ideas were shared and explored. Artists Rick Guidice and Don Davis created many paintings and illustrations of what colony designs like Bernal Spheres, Double Cylinders, and Toroidal Colonies might look like.

This piece by artist Don Davis depicts the end-cap of a cylindrical colony. Notice the suspension bridge, and people enjoying themselves by a river. Image: Don Davis, NASA Ames Research Center

This cut-away image of a Bernal Sphere colony was created by artist Rick Guidice. Image: Rick Guidice, NASA Ames Research Center

NASA continues to work with artists, though the nature of the relationship has changed over the decades. Artists are often used to flesh out new discoveries when images are not available. Cassini’s so-called Grand Finale, when it will orbit between Saturn and its rings 22 times before crashing into the planet, was conceptualized by an unnamed artist.

An artist's illustration of the Cassini probe's Grand Finale. Image: NASA/JPL/CalTech — An artist’s illustration of the Cassini probe’s Grand Finale. Image: NASA/JPL/CalTech

The recent discovery of the exoplanets in the TRAPPIST-1 system was huge news. It still is. But TRAPPIST-1 is over 40 light years away, and NASA relied on artists to bring the discovery to life. This illustration was widely used to help us understand what planets orbiting the TRAPPIST-1 Red Dwarf might look like.

Illustration showing the possible surface of TRAPPIST-1f, one of the newly discovered planets in the TRAPPIST-1 system. Credits: NASA/JPL-Caltech

NASA now has quite a history of relying on art to convey what words can’t do. Space colonies, distant solar systems, and spacecraft ending their missions on other worlds, have all relied on the work of artists. But if I had to choose a favorite, it would probably be the 1981 water color by artist Henry Casselli. It makes you wonder what it’s like for an individual to take part in these species-defining endeavours. Just one person, sitting, contemplating, and preparing.

This Henry Casselli watercolor shows astronaut John Young preparing for a launch on April 12, 1981. What must he have been thinking as he prepared for the first flight of the Space Shuttle Program? Image: Henry Casselli, Courtesy NASA Art Program

April 18, 2017April 28, 2017 by Evan Gough

Ceres Prank Lands Bart Simpson In Detention For Eternity

Do you see Bart Simpson's face on these surface features on Ceres? Researchers studying the surface of the dwarf planet for evidence of the presence of ice do. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA, taken by Dawn Framing Camera

Human-kind has a long history of looking up at the stars and seeing figures and faces. In fact, there’s a word for recognizing faces in natural objects: pareidolia. But this must be the first time someone has recognized Bart Simpson’s face on an object in space.

Researchers studying landslides on the dwarf planet Ceres noticed a pattern that resembles the cartoon character. The researchers, from the Georgia Institute of Technology, are studying massive landslides that occur on the surface of the icy dwarf. Their findings are reinforcing the idea that Ceres has significant quantities of frozen water.

Dwarf planet Ceres is the largest object in the asteroid belt between Mars and Jupiter. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA, taken by Dawn Framing Camera

In a new paper in the journal Nature Geoscience, the team of scientists, led by Georgia Tech Assistant Professor and Dawn Science Team Associate Britney Schmidt, examined the surface of Ceres looking for morphologies that resemble landslides here on Earth.

Research shows us that Ceres probably has a subsurface shell that is rich with water-ice. That shell is covered by a layer of silicates. Close examination of the type, and distribution, of landslides at different latitudes adds more evidence to the sub-surface ice theory.

Ceres is pretty big. At 945 km in diameter, it’s the largest object in the asteroid belt between Mars and Jupiter. It’s big enough to be rounded by its own gravity, and it actually comprises about one third of the mass of the entire asteroid belt.

Type 1 landslides on Ceres are large and occur at higher latitudes. Image: Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA, taken by Dawn Framing Camera

The team used observations from the Dawn Framing Camera to identify three types of landslides on Ceres’ surface:

Type 1 are large, rounded features similar to glacier features in the Earth’s Arctic region. These are found mostly at high latitudes on Ceres, which is where most of the ice probably is.
Type 2 are the most common. They are thinner and longer than Type 1, and look like terrestrial avalanche deposits. They’re found mostly at mid-latitudes on Ceres. The researchers behind the study thought one of them looked like Bart Simpson’s face.
Type 3 occur mostly at low latitudes near Ceres’ equator. These are always found coming from large impact craters, and probably formed when impacts melted the sub-surface ice.

Type 3 landslides on Ceres occur at low latitudes at large craters, and form when ice is melted by impacts. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA, taken by Dawn Framing Camera

The authors of the study say that finding larger landslides further away from the equator is significant, because that’s where most of the ice is.

“Landslides cover more area in the poles than at the equator, but most surface processes generally don’t care about latitude,” said Schmidt, a faculty member in the School of Earth and Atmospheric Sciences. “That’s one reason why we think it’s ice affecting the flow processes. There’s no other good way to explain why the poles have huge, thick landslides; mid-latitudes have a mixture of sheeted and thick landslides; and low latitudes have just a few.”

Key to understanding these results is the fact that these types of processes have only been observed before on Earth and Mars. Earth, obviously, has water and ice in great abundance, and Mars has large quantities of sub-surface ice as well. “It’s just kind of fun that we see features on this small planet that remind us of those on the big planets, like Earth and Mars,” Schmidt said. “It seems more and more that Ceres is our innermost icy world.”

“These landslides offer us the opportunity to understand what’s happening in the upper few kilometers of Ceres,” said Georgia Tech Ph.D. student Heather Chilton, a co-author on the paper. “That’s a sweet spot between information about the upper meter or so provided by the GRaND (Gamma Ray and Neutron Detector) and VIR (Visible and Infrared Spectrometer) instrument data, and the tens of kilometers-deep structure elucidated by crater studies.”

It’s not just the presence of these landslides, but the frequency of them, that upholds the icy-mantle idea on Ceres. The study showed that 20% to 30% of craters on Ceres larger than 10 km have some type of landslide. The researchers say that upper layers of Ceres’ could be up to 50% ice by volume.

April 15, 2017April 28, 2017 by Evan Gough

NASA Releases Spellbinding Images Of Earth At Night

Composite image of continental U.S. at night, 2016. Credits: NASA Earth Observatory images by Joshua Stevens, using Suomi NPP VIIRS data from Miguel Román, NASA's Goddard Space Flight Center

NASA strives to explore space and to expand our understanding of our Solar System and beyond. But they also turn their keen eyes on Earth in an effort to understand how our planet is doing. Now, they’re releasing a new composite image of Earth at night, the first one since 2012.

We’ve grown accustomed to seeing these types of images in our social media feeds, especially night-time views of Earth from the International Space Station. But this new image is much more than that. It’s part of a whole project that will allow scientists—and the rest of us—to study Earth at night in unprecedented detail.

Night-time views of Earth have been around for 25 years or so, usually produced several years apart. Comparing those images shows clearly how humans are changing the face of the planet. Scientists have been refining the imaging over the years, producing better and more detailed images.

The team behind this is led by Miguel Román of NASA’s Goddard Space Flight Center. They’ve been analyzing data and working on new software and algorithms to improve the quality, clarity, and availability of the images.

This new work stems from a collaboration between the National Oceanic and Atmospheric Administration (NOAA) and NASA. In 2011, NASA and NOAA launched a satellite called the Suomi National Polar-orbiting Partnership (NPP) satellite. The key instrument on that satellite is the Visible Infrared Imaging Radiometer Suite (VIIRS), a 275 kg piece of equipment that is a big step forward in Earth observation.

VIIRS detects photons of light in 22 different wavelengths. It’s the first satellite instrument to make quantitative measurements of light emissions and reflections, which allows researchers to distinguish the intensity, types and the sources of night lights over several years.

Composite image of Mid-Atlantic and Northeastern U.S. at night, 2016. Credits: NASA Earth Observatory images by Joshua Stevens, using Suomi NPP VIIRS data from Miguel Román, NASA's Goddard Space Flight Center — Composite image of Mid-Atlantic and Northeastern U.S. at night, 2016.
Credits: NASA Earth Observatory images by Joshua Stevens, using Suomi NPP VIIRS data from Miguel Román, NASA’s Goddard Space Flight Center

Producing these types of maps is challenging. The raw data from SUOMI NPP and its VIIRS instrument has to be skillfully manipulated to get these images. The main challenge is the Moon itself.

As the Moon goes through its different phases, the amount of light hitting Earth is constantly changing. Those changes are predictable, but they still have to be accounted for. Other factors have to be managed as well, like seasonal vegetation, clouds, aerosols, and snow and ice cover. Other changes in the atmosphere, though faint, also affect the outcome. Phenomenon like auroras change the way that light is observed in different parts of the world.

The newly released maps were made from data throughout the year, and the team developed algorithms and code that picked the clearest night views each month, ultimately combining moonlight-free and moonlight-corrected data.

A glittering night-time map of Europe. Looks like there's a Kraftwerk concert happening in Dusseldorf! NASA Earth Observatory images by Joshua Stevens, using Suomi NPP VIIRS data from Miguel Román, NASA's Goddard Space Flight Center — A glittering night-time map of Europe. Looks like there’s a Kraftwerk concert happening in Dusseldorf! NASA Earth Observatory images by Joshua Stevens, using Suomi NPP VIIRS data from Miguel Román, NASA’s Goddard Space Flight Center

The SUOMI NPP satellite is in a polar orbit, and it observes the planet in vertical swaths that are about 3,000 km wide. With its VIIRS instrument, it images almost every location on the surface of the Earth, every day. VIIRS low-light sensor has six times better spatial resolution for distinguishing night lights, and 250 times better resolution overall than previous satellites.

What do all those numbers mean? The team hopes that their new techniques, combined with the power of VIIRS, will create images with extraordinary resolution: the ability to distinguish a single highway lamp, or fishing boat, anywhere on the surface of Earth.

Composite image of Nile River and surrounding region at night, 2016. Credits: NASA Earth Observatory images by Joshua Stevens, using Suomi NPP VIIRS data from Miguel Román, NASA's Goddard Space Flight Center — Composite image of Nile River and surrounding region at night, 2016.
Credits: NASA Earth Observatory images by Joshua Stevens, using Suomi NPP VIIRS data from Miguel Román, NASA’s Goddard Space Flight Center

Beyond thought-provoking eye-candy for the rest of us, these images of night-time Earth have practical benefits to researchers and planners.

“Thanks to VIIRS, we can now monitor short-term changes caused by disturbances in power delivery, such as conflict, storms, earthquakes and brownouts,” said Román. “We can monitor cyclical changes driven by reoccurring human activities such as holiday lighting and seasonal migrations. We can also monitor gradual changes driven by urbanization, out-migration, economic changes, and electrification. The fact that we can track all these different aspects at the heart of what defines a city is simply mind-boggling.”

These three composite images provide full-hemisphere views of Earth at night. The clouds and sun glint — added here for aesthetic effect — are derived from MODIS instrument land surface and cloud cover products. Credits: NASA Earth Observatory images by Joshua Stevens, using Suomi NPP VIIRS data from Miguel Román, NASA's Goddard Space Flight Center — These three composite images provide full-hemisphere views of Earth at night. The clouds and sun glint — added here for aesthetic effect — are derived from MODIS instrument land surface and cloud cover products.
Credits: NASA Earth Observatory images by Joshua Stevens, using Suomi NPP VIIRS data from Miguel Román, NASA’s Goddard Space Flight Center

These maps of night-time Earth are a powerful tool. But the newest development will be a game-changer: Román and his team aim to provide daily, high-definition views of Earth at night. Daily updates will allow real-time tracking of changes on Earth’s surface in a way never before possible.

Maybe the best thing about these upcoming daily night-time light maps is that they will be publicly available. The SUOMI NPP satellite is not military and its data is not classified in any way. They hope to have these daily images available later this year. Once the new daily light-maps of Earth are available, it’ll be another powerful tool in the hands of researchers and planners, and the rest of us.

These maps will join other endeavours like NASA-EOSDIS Worldview. Worldview is a fascinating, easy-to-use data tool that anyone can access. It allows users to look at satellite images of the Earth with user-selected layers for things like dust, smoke, draught, fires, and storms. It’s a powerful tool that can change how you understand the world.

April 13, 2017April 28, 2017 by Evan Gough

Researchers Image Dark Matter Bridge Between Galaxies

This false color, composite image shows two galaxies, white, connected by a bridge of dark matter, red. The two galaxies are about 40 light years apart. Image: S. Epps & M. Hudson / University of Waterloo

Dark matter is mysterious stuff, because we can’t really “see” it. But that hasn’t stopped scientists from researching it, and from theorizing about it. One theory says that there should be filament structures of dark matter connecting galaxies. Scientists from the University of Waterloo have now imaged one of those dark matter filaments for the first time.

The two scientists, Seth D. Epps and Michael J. Hudson, present their results in a paper at the Monthly Notices of the Royal Astronomy Society.

Theory predicts that filaments of dark matter connect galaxies together, by reaching from the dark matter halo of one galaxy to the same halo in another galaxy. Other researchers have found dark matter filaments connecting entire galaxy clusters, but this is the first time that filaments have been imaged between individual galaxies.

“This image moves us beyond predictions to something we can see and measure.” – Mike Hudson, University of Waterloo

“For decades, researchers have been predicting the existence of dark-matter filaments between galaxies that act like a web-like superstructure connecting galaxies together,” said Mike Hudson, a professor of astronomy at the University of Waterloo. “This image moves us beyond predictions to something we can see and measure.”

Dark matter makes up about 25% of the Universe. But it doesn’t shine, reflect, or interact with light in any way, so it’s difficult to study. The only way we can really study it is by observing gravity. In this study, the pair of astronomers used the weak gravitational lensing technique.

Weak gravitational lensing relies on the effect that mass has on light. Enough concentrated mass in the foreground—dark matter in this case—will warp light from distant sources in the background.

When dealing with something as large as a super-massive Black Hole, gravitational lensing is quite pronounced. But galaxy-to-galaxy filaments of dark matter are much less dense than a black hole, so their individual effect is minimal. What the astronomers needed was the combined data from multiple galaxy pairs in order to detect the weak gravitational lensing.

Key to this study is the Canada-France-Hawaii Telescope. It performed a multi-year sky survey that laid the groundwork for this study. The researchers combined lensing images of over 23,000 pairs of galaxies 4.5 billion light years away. The resulting composite image revealed the filament bridge between the two galaxies.

“By using this technique, we’re not only able to see that these dark matter filaments in the universe exist, we’re able to see the extent to which these filaments connect galaxies together.” – Seth D. Epps, University of Waterloo

We still don’t know what dark matter is, but the fact that scientists were able to predict these filaments, and then actually find them, shows that we’re making progress understanding it.

We’ve known about the large scale structure of the Universe for some time, and we know that dark matter is a big part of it. Galaxies tend to cluster together, under the influence of dark matter’s gravitational pull. Finding a dark matter bridge between galaxies is an intriguing discovery. It at least takes a little of the mystery out of dark matter.

April 13, 2017April 28, 2017 by Evan Gough

NASA Bombshell: Key Ingredient For Life Discovered On Enceladus

Scientists recently determined that a certain strain of Earth bacteria could thrive under conditions found on Enceladus. Credit: NASA/JPL/Space Science Institute

NASA has announced the discovery of hydrogen in the plumes on Enceladus. This is huge news, and Cassini scientists have looked forward to this day. What it means is that there is a potential source of energy for microbes in the oceans of Enceladus, and that energy from the Sun is not required to support life.

We’ve known about the plumes on Enceladus for a while now, and Cassini has even flown through those plumes to determine their content. But hydrogen was never discovered until now. What it means is that there is a geochemical source for hydrogen in Enceladus’ ocean, coming from the interaction between warm water and rocks.

“This is the closest we’ve come, so far, to identifying a place with some of the ingredients needed for a habitable environment.” – Thomas Zurbuchen, NASA.

This is a capstone finding, according to NASA. As far as we know, life needs three things to exist: water, energy, and the right chemicals. We know it has the necessary chemicals, we know it has water, and we now know it has a source of energy.

On Earth, hydrothermal vents deep in the ocean floor provide the energy for a web of life reliant on those vents. Bacteria live there, forming the base of a food chain that can include tube worms, shrimp, and other life forms. This discovery points to the possibility that similar communities might exist in the sub-surface ocean of Enceladus.

“This is the closest we’ve come, so far, to identifying a place with some of the ingredients needed for a habitable environment,” said Thomas Zurbuchen, associate administrator for NASA’s Science Mission Directorate at Headquarters in Washington.

Microbes in Enceladus’ ocean could use the hydrogen in a process called methanogenesis. They obtain energy by combining hydrogen with dissolved carbon dioxide in the water. This process produces a methane by-product. Methanogenesis is a bedrock process at the root of life here on Earth.

“Confirmation that the chemical energy for life exists within the ocean of a small moon of Saturn is an important milestone in our search for habitable worlds beyond Earth,” said Linda Spilker, Cassini project scientist at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California.

Hubble Confirms Plumes On Europa

NASA has also announced that the Hubble Space Telescope has confirmed the presence of plumes on another of our Solar System’s icy moons, Europa.

These plumes were first seen by the Hubble in 2014, but were never seen again. Since repeatability is key in science, those findings were put on the back burner. But in 2016, NASA announced today, Hubble spotted them again, in the same place. This is the same spot that the Galileo probe noticed a thermal hot spot.

We don’t know if Europa has hydrogen in its oceans, but it’s easy to see where this is going. NASA’s excitement is palpable.

What’s Next?

NASA’s Europa Clipper mission will visit Europa and determine the thickness of its ice layer, as well as the depth and salinity of its ocean. It will also analyze the atmosphere and the composition of the plumes. Europa Clipper will fill in a lot of gaps in our understanding.

Europa Clipper will be launched around 2022, but a mission to Enceladus will have to wait a little longer. One mission under consideration in NASA’s Discovery program is ELF, Enceladus Life Finder. ELF would fly through Enceladus’ plumes 8 or 10 times, taking more detailed samples of their content.

This enhanced-color Cassini view of southern latitudes on Enceladus features the bluish “tiger stripe” fractures that rip across the south polar region. These tiger stripes form over hydrothermal vents in the ocean, the source of Enceladus’ plumes. Credits: NASA/JPL-Caltech/Space Science Institute

The discovery of hydrogen in the plumes of Enceladus is huge news any way you look at it. But that discovery begs the question: Are we doing it all wrong? Are we looking for life in the wrong places?

The search for life elsewhere in the Universe, so far, has mostly revolved around exoplanets. And then refining that search to identify exoplanets that are in the habitable zones of their stars. We’re searching for other Earths, basically.

But maybe we should be changing our focus. Maybe it’s the ice worlds, including icy exomoons, that are the most likely targets for our search. This new evidence from NASA’s Cassini mission, and from the Hubble Space Telescope, suggests that in our Solar System at least, they are the best place to search.

One Final Ingredient Needed?

There’s a fourth ingredient needed for life. Once there is water, energy, and the necessary chemicals, life needs time to get going. How much time, we’re not exactly certain. But this is where Enceladus and Europa are different.

Europa is about 4 billion years old, or so we think. That’s only half a billion years younger than Earth, and we think life started on Earth about 3.5 billion years ago. This hints that, if conditions on Europa are favorable, life has had a long time to get going. Of course, that doesn’t mean it has.

On the other hand, Enceladus is probably much younger. A study of the orbits of Saturn’s moons suggests that Enceladus may only be 100 million years old. If that’s true, it’s not very much time for life to get going.

The hydrogen discovery is huge news. There are still a lot of questions, of course, and lots to be debated. But confirming a source of energy on Enceladus builds the case for the same type of hydrothermal vent life that we see on Earth.

Now all we need is a mission to Enceladus.

April 4, 2017April 28, 2017 by Evan Gough

TRAPPIST-1 Is Showing A Bit Too Much Flare

Artist's impression of a system of exoplanets orbiting a low mass, red dwarf star. Credit: NASA/JPL

It turns out that the TRAPPIST-1 star may be a terrible host for the TRAPPIST planets announced in February.

The TRAPPIST-1 star, a Red Dwarf, and its 7 planets caused a big stir in February when it was discovered that 3 of the rocky planets are in the habitable zone. But now more data is coming which suggests that the TRAPPIST-1 star is much too volatile for life to exist on its planets.

Red Dwarfs are much dimmer than our Sun, but they also last much longer. Their lifetimes are measured in trillions of years, not billions. Their long lives make them intriguing targets in the search for habitable worlds. But some types of Red Dwarf stars can be quite unstable when it comes to their magnetism and their flaring.

Our own Sun produces flares, but we are protected by our magnetosphere, and by the distance from the Sun to Earth. Credit: NASA/ Solar Dynamics Observatory,

A new study analyzed the photometric data on TRAPPIST-1 that was obtained by the K2 mission. The study, which is from the Konkoly Observatory and was led by astronomer Krisztián Vida, suggests that TRAPPIST-1 flares too frequently and too powerfully to allow life to form on its planets.

The study identified 42 strong flaring events in 80 days of observation, of which 5 were multi-peaked. The average time between flares was only 28 hours. These flares are caused by stellar magnetism, which causes the star to suddenly release a lot of energy. This energy is mostly in the X-ray or UV range, though the strongest can be seen in white light.

While it’s true that our Sun can flare, things are much different in the TRAPPIST system. The planets in that system are closer to their star than Earth is to the Sun. The most powerful flare observed in this data correlates to the most powerful flare observed on our Sun: the so-called Carrington Event.The Carrington Event happened in 1859. It was an enormously powerful solar storm, in which a coronal mass ejection struck Earth’s magnetosphere, causing auroras as far south as the Caribbean. It caused chaos in telegraph systems around the world, and some telegraph operators received electric shocks.

Earth survived the Carrington Event, but things would be much different on the TRAPPIST worlds. Those planets are much closer to their Sun, and the authors of this study conclude that storms like the Carrington Event are not isolated incidents on TRAPPIST-1. They occur so frequently that they would destroy any stability in the atmosphere, making it extremely difficult for life to develop. In fact, the study suggests that the TRAPPIST-1 storms could be hundreds or thousands of times more powerful than the storms that hit Earth.

A study from 2016 shows that these flares would cause great disturbances in the chemical composition of the atmosphere of the planets subjected to them. The models in that study suggest that it could take 30,000 years for an atmosphere to recover from one of these powerful flares. But with flares happening every 28 hours on TRAPPIST-1, the habitable planets may be doomed.

The Earth’s magnetic field helps protects us from the Sun’s outbursts, but it’s doubtful that the TRAPPIST planets have the same protection. This study suggests that planets like those in the TRAPPIST system would need magnetospheres of tens to hundreds of Gauss, whereas Earth’s magnetosphere is only about 0.5 Gauss. How could the TRAPPIST planets produce a magnetosphere powerful enough to protect their atmosphere?

It’s not looking good for the TRAPPIST planets. The solar storms that hit these worlds are likely just too powerful. Even without these storms, there are other things that may make these planets uninhabitable. They’re still an intriguing target for further study. The James Webb Space Telescope should be able to characterize the atmosphere, if any, around these planets.

Just don’t be disappointed if the James Webb confirms what this study tells us: the TRAPPIST system is a dead, lifeless, grouping of planets around a star that can’t stop flaring.

March 30, 2017April 4, 2017 by Evan Gough

The Ever-Working Mars Orbiter Passes 50,000 Orbits

This image is a mosaic of all the images captured by the Context Camera (CTX) on NASA's Mars Reconnaissance Orbiter. The CTX has imaged over 99% of the Martian surface. Image: NASA/JPL-Caltech/MSSS

Most of us never do one thing 50,000 times in our life. So for NASA’s Mars Reconnaissance Orbiter (MRO), completing 50,000 orbits around the red planet is a big deal. And, it only took 10 years to do so.

The MRO could be called one of NASA’s flagship missions. It’s presence in orbit around Mars has helped open up our understanding of that planet immensely. And it’s done so while providing us a steady stream of eye candy.

This recent image from MRO’s HiRise camera shows dune structure inside an impact crater. Image: NASA/JPL/University of Arizona

MRO was launched in 2005 and reached Mars orbit in March, 2006. After 10 years at work, it has accomplished a lot. In a recent press release, NASA calls the MRO “the most data-productive spacecraft yet.” Though most of us might know the orbiter because of it’s camera, the High-Resolution Imaging Science Experiment (HiRise), the MRO actually has a handful of other instruments that help the orbiter achieve its objectives. In broad terms, those objectives are:

to study the history of water on Mars
to look at small scale features on the surface, and identify landing sites for future Mars missions
to act as a communications relay between Mars and Earth

MRO investigating Martian water cycle – This artist’s concept represents the “Follow the Water” theme of NASA’s Mars Reconnaissance Orbiter mission. The orbiter’s science instruments monitor the present water cycle in the Mars atmosphere and the associated deposition and sublimation of water ice on the surface, while probing the subsurface to see how deep the water-ice reservoir extends. Image: By NASA/JPL/Corby Waste – http://photojournal.jpl.nasa.gov/catalog/PIA07241 (image link), Public Domain, https://commons.wikimedia.org/w/index.php?curid=374810 (Larger image here.

MRO’s HiRise camera gets all the glory, but it’s another onboard camera, the Context Camera (CTX), that is the real workhorse. The CTX is a much lower resolution than the HiRise, but its file sizes are much more manageable, an important consideration when every file has to travel from Mars to Earth—an average distance of about 225 million km.

CTX has captured 90,000 images so far in MRO’s mission, and each one captures details smaller than a tennis court. In the course of the mission so far, CTX has images that cover 99.1% of the Martian surface. Over 60% of the planet has been covered twice.

“Reaching 99.1-percent coverage has been tricky…” – Context Camera Team Leader Michael Malin

“Reaching 99.1-percent coverage has been tricky because a number of factors, including weather conditions, coordination with other instruments, downlink limitations, and orbital constraints, tend to limit where we can image and when,” said Context Camera Team Leader Michael Malin of Malin Space Science Systems, San Diego.

Malin said, “Single coverage provides a baseline we can use for comparison with future observations, as we look for changes. Re-imaging areas serves two functions: looking for changes and acquiring stereoscopic views from which we can make topographic maps.”

Because the CTX captures image of the same surface areas twice, it documents changes on the surface. There have been over 200 instances of impact craters appearing in a second image of the same area. Scientists have used this to calculate the rate that meteorites impact Mars.

The instruments on board the MRO work as a team. The CTX can capture images of areas of interest, and the HiRise can be used for higher-resolution images of the same area. By locating fresh impact craters, then studying them more closely, the MRO has helped discover the presence of what looked like sub-surface ice on Mars. A third instrument, the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM), confirmed the presence of ice.

The CTX is the workhorse camera, and the HiRise is the diva, but MRO actually has a third camera: the Mars Color Imager (MARCI). MARCI is a very low resolution camera compared to the others. It’s also a wide-angle camera with really only one purpose: characterizing Martian weather. Every day, MARCI takes about 84 images which together create a daily global map of Mars. You can see a weekly Martian weather report from MARCI here.

The MRO recently manoeuvered itself into position for its next task—helping the InSight Lander. The MRO must receive critical radio transmissions from NASA’s InSight Lander as it descends to Mars. Insight will use its instruments to examine the interior of Mars for clues to how rocky planets form. Not only did MRO help find a landing spot for Insight, but it will hold the lander’s hand as it descends, and it will act as a data relay.

“After 11 and a half years in flight, the spacecraft is healthy and remains fully functional.” – MRO Project Manager Dan Johnston.

There’s no end in sight for the MRO. It just keeps going and going, and fulfilling its mission objectives on a continuing basis. “After 11 and a half years in flight, the spacecraft is healthy and remains fully functional,” said MRO Project Manager Dan Johnston at NASA’s Jet Propulsion Laboratory, Pasadena, California. “It’s a marvelous vehicle that we expect will serve the Mars Exploration Program and Mars science for many more years to come.”

March 25, 2017April 4, 2017 by Evan Gough

Juno’s Monday Jupiter Flyby Promises New Batch of Images & Science

This image of Jupiter from the Juno probe shows an intricate dance of storms and swirls. The enhanced color image was captured on February 2nd, from only 14,500 km above the gas giant's cloud tops. Image: NASA/JPL-Caltech/SwRI/MSSS/Roman Tkachenko

Juno is only part way through its mission to Jupiter, and already we’ve seen some absolutely breathtaking images of the gas giant. On Monday, the Juno spacecraft will flyby Jupiter again. This will be the craft’s 5th flyby of the gas giant, and it’ll provide us with our latest dose of Jupiter science and images. The first 4 flybys have already exceeded our expectations.

Juno will approach to within 4,400 km of Jupiter’s cloud tops, and will travel at a speed of 207,600 km/h. During this time of closest approach, called a perijove, all of Juno’s eight science instruments will be active, along with the JunoCam.

The JunoCam is not exactly part of the science payload. It was included in the missions to help engage the public with the mission, and it appears to be doing that job well. The Junocam’s targets have been partly chosen by the public, and NASA has invited anyone who cares to to download and process raw Junocam images. You can see those results throughout this article.

This image of Jupiter’s dancing cloud tops was captured during perijove 3. Image: NASA / JPL-Caltech / SwRI / MSSS / Kootenay Nature Photos © cc nc sa

This is Juno’s 5th flyby, but only its 4th science pass. During Juno’s first encounter with Jupiter, the science instruments weren’t active. Even so, after only 3 science passes, we have learned some things about Jupiter.

“We are excited to see what new discoveries Juno will reveal.” – Scott Bolton, NASA’s Principal Investigator for the Juno Mission

“This will be our fourth science pass — the fifth close flyby of Jupiter of the mission — and we are excited to see what new discoveries Juno will reveal,” said Scott Bolton, principal investigator of Juno from the Southwest Research Institute in San Antonio. “Every time we get near Jupiter’s cloud tops, we learn new insights that help us understand this amazing giant planet.”

We’ve already learned that Jupiter’s intense magnetic fields are much more complicated than we thought. We’ve learned that the belts and zones in Jupiter’s atmosphere, which are responsible for the dazzling patterns on the cloud tops, extend much deeper into the atmosphere than we thought. And we’ve discovered that charged material expelled from Io’s volcanoes helps cause Jupiter’s auroras.

The South Pole of Jupiter, taken during perijove 3. Image: NASA / JPL-Caltech / SwRI / MSSS / Luca Fornaciari © cc nc sa

Juno has the unprecedented ability to get extremely close to Jupiter. This next flyby will bring it to within 4,400 km of the cloud tops. But to do so, Juno has to pay a price. Though the sensitive equipment on the spacecraft is protected inside a titanium vault, Jupiter’s powerful radiation belts will still take a toll on the electronics. But that’s the price Juno will pay to perform its mission.

Jupiter’s dazzle as revealed by JunoCam and Shane Drever. Image: NASA / JPL-Caltech / SwRI / MSSS / Shane Drever © cc nc sa

Other missions, like Cassini, have been measured in years, while Juno’s will be measured in orbits. And once it’s completed its final orbit, it will be sent to its destruction in Jupiter’s atmosphere.

But before that happens, there’s a lot of science to be done, and a lot of stunning images to be captured.

Here’s an interview with the man leading the Juno Mission: Understanding Juno’s Orbit: An Interview with NASA’s Scott Bolton.

Here is the page for the JunoCam: https://www.missionjuno.swri.edu/junocam

March 24, 2017April 4, 2017 by Evan Gough

German ‘Largest Artificial Sun’ To Generate Climate Friendly Fuel

Technicians at the DLR's Institute for Solar Research inspecting lamps in the Synlight. Image: DLR/Markus Hauschild.

Hydrogen is the most abundant element in the Universe. But here on Earth, it’s rather rare. That’s unfortunate, because in our warming world, its status as an emissions-free fuel makes it a coveted chemical. If German researchers are successful, their Synlight project will help make renewable hydrogen fuel a reality.

Dubbed the “artificial Sun”, the Synlight uses concentrated light to power Thermochemical Water Splitting (TWS.) Every school child knows you can produce hydrogen by electrolysis—running an electric current through water. But that takes an enormous amount of electricity. TWS might be a better way of getting hydrogen out of water, but it takes an enormous amount of energy too, and that’s what the German research is about.

When combusted with pure oxygen—inside a fuel cell for example—hydrogen’s only waste product is water. No greenhouse gases or particulates are produced. But if we want to use it to power our cars, buses, trucks, and even airplanes, we need enormous amounts of it. And we need to produce it cost-effectively.

“Renewable energies will be the mainstay of global power supply in the future.” – Karsten Lemmer DLR Executive Board Member

The idea is to use the heat generated by Concentrated Solar Power (CSP) to extract hydrogen from water, thereby eliminating the need for electricity. CSP systems use mirrors or lenses to concentrate a large area of sunlight into a small area. The heat from that action can be used to power TWS. The Synlight project in Germany is demonstrating the viability of TWS by mimicking the effect of concentrated sunlight. In doing so, researchers there are building what’s being called the world’s largest artificial Sun.

Each of Synlight’s 149 zenon short-arc lamps can be controlled individually. Image: DLR/Synlight/Markus Hauschild

German researchers at the German Aerospace Center (DLR) at Julich near Cologne built the Synlight, a system of 149, high power lamps of the type used in film projections. When all these lamps are turned on, Synlight produces light that is about 10,000 times more intense than natural sunlight on Earth. When all the lamps are aimed at a single spot, Synlight generates temperatures up to 3000 Celsius. The challenge now is to develop materials and processes that can operate in such an extreme temperature.

The 15m tall Synlight experiment is housed in this building in Julich. The building contains 3 separate radiation chambers for different experiments. Image: DLR CC By 3.0

The Synlight system itself uses an enormous amount of electrical power to operate. But that’s often the case with experimental facilities. The Synlight project will mimic the effect of intense, continuous solar energy, something that is not readily available in Germany. By building a test facility powered by electricity, researchers will be able to reliably perform experiments without being delayed or affected by cloudy weather.

“Fuels, propellants and combustibles acquired using solar power offer immense potential for long-term storage and the production of chemical raw materials, and the reduction of carbon dioxide emissions. Synlight will enhance our research in this field.” – Karsten Lemmer, DLR Executive Board Member

As Johannes Remmel, the North Rhine-Westphalia Minister for Climate Protection, said, “”We need to expand existing technology in practical ways in order to achieve renewable energy targets, but the energy transition will falter without investments in innovative research, in state-of-the-art technologies and in global lighthouse projects like Synlight.”

The DLR is involved in the PS10 solar power tower in Spain. The PS10 is the world’s fist commercial concentrating solar power tower. Image: By afloresm – SOLUCAR PS10, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=2821733

This is not the German Aerospace Center’s first foray in concentrated solar power. They’re involved in a number of projects to advance concentrated solar power and thermal water splitting. The DLR is a partner in the Hydrosol II pilot in Spain. It’s a reactor for solar thermochemical hydrogen production that has been in operation since 2008. They’re also involved in the first commercially operated solar tower plant, an 11 megawatt system in Spain called the PS10 solar power tower.