Can We Call the Bright Spot in Ceres’ Occator Crater a Cryovolcano Yet?

Evidence is mounting around the cryovolcanic history of the solar system’s innermost dwarf planet — and its most recent eruptions may have happened within the last four million years.


Since NASA’s Dawn mission arrived at dwarf planet Ceres in 2015, we’ve been treated to some wonderfully detailed images of the small world’s pockmarked terrain. Understanding the underlying processes of what is believed to be an ice-filled celestial body, however, is taking some time to decipher. But with more observations comes more understanding and planetary scientists are getting close to realizing what lies beneath those craters and, possibly, unlocking the secrets behind a very icy and very alien phenomenon we have no experience of in our terrestrial lives.

That phenomenon is cryovolcanoes. And Ceres seems to have them.

The most startling feature on Ceres is Occator Crater. This 57 mile-wide feature is the result of a massive impact tens of millions of years ago. Large craters on small worlds isn’t necessarily a strange thing in our battered solar system, but what is strange about Occator is the very bright feature (and small bright patches surrounding it) in the crater’s center. Even before Dawn arrived in orbit and only fuzzy images of Ceres were available, hopes were high that this bright anomaly in the otherwise gray Cererian landscape could be indicative of ices or some mineral compound that was formed by the presence of water.

There have been many studies into Occator’s icy center, but new research into the crater’s age compared to the bright spot’s age appears to, once again, point to a cryovolcanic origin.

Cryovolcanoes — or, simply, ice volcanoes — are hypothetical features that are believed to be common throughout the outer solar system. These ice volcanoes are thought to erupt in a similar fashion to the volcanoes we have on Earth, but instead of molten rock, these volcanoes erupt ice-cold volatiles — like water, methane or ammonia. Dwarf planet Pluto, for example, has features that look like cryovolcanoes, as does Saturn’s moon Titan and Jupiter’s moon Ganymede. These locations are extremely cold and known to contain large quantities of methane and water, so internal heating (caused by radioactive decay or tidal processes) melt the ices and force them to the surface. When they vent through the crust, gases are released and the liquids quickly freeze and sublimate.

Around these vents, cryovolcanoes will grow, and if Ceres really does have its own ice volcanoes, this will be the closest planetary body to the sun (and Earth) known to have them.

Now, in research headed by the Max Planck Institute for Solar System Research (MPS) in Göttingen, Germany, scientists using Dawn data have, for the first time, taken a stab at dating the age of the bright material in the center of Occator Crater and realized that the location has likely been the site of many cryovolcanic eruptions in the recent past.

Occator Crater as observed by NASA’s Dawn spacecraft (NASA/JPL-Caltech/UCLA/MPS/DLR/IDA)

In the center of Occator, a pit measuring around 7 miles wide can be found, likely formed during the massive impact approximately 30 million years ago. But around the edges of that pit are mountains, some 750 meters high, and in the center is a cracked dome measuring 400 meters high and nearly 2 miles wide. This bright dome is called Cerealia Facula and surrounding it appears to be material that was spewed from a cryovolcanic vent. Analysis has shown that this material contains salts that were formed in the presence of water from Ceres’ interior and then deposited onto the surface. The minerals around Cerealia Facula has been dated to only four million years, meaning that there has been cryovolcanic eruptions long after the Occator impact punctured Ceres’ crust.

“The age and appearance of the material surrounding the bright dome indicate that Cerealia Facula was formed by a recurring, eruptive process, which also hurled material into more outward regions of the central pit,” said Andreas Nathues, lead investigator of Dawn’s Framing Camera. “A single eruptive event is rather unlikely.” As noted in an MPS news release, Jupiter moons Callisto and Ganymede have similar features that are also believed to be related to cryovolcanic eruptions.

“The large impact that tore the giant Occator crater into the surface of the dwarf planet must have originally started everything and triggered the later cryovolcanic activity,” added Nathues.

Previous imagery of haze inside Occator Crater has led to the suspicion that ices remain on the surface today; the haze could be vapor from sublimating water ice exposed on the surface having been forced to the surface from Ceres’ interior. Evidence for this haze has been supported by other studies and appears to vary throughout the day as one would expect — increased sunlight would accelerate sublimation (ice turning from a solid to a vapor without passing through the liquid phase).

If volatiles are still being extruded through this vent today, this would seem to indicate that, in addition to the cryovolcanic eruptions in the last four million years, some form of activity continues to this day. Add this to the recent discovery of organic material on Ceres’ surface, this small world has become a very big asset for planetary science.

For more on Ceres’ icy eruptions, check out one of my last DNews videos:

Mars’ Ancient Mega-Floods Are Still Etched Into the Red Planet

Around 3.5 billion years ago — when basic life was just gaining a foothold on Earth — the Tharsis region on Mars was swamped with vast floods that scar the landscape to this day.

Rendered perspective view of Worcester Crater using Mars Express elevation data. The dramatic crater rim was carved by the flow of ancient floodwater (ESA)

Mars wears its geological history like a badge of honor — ancient craters remain unchanged for hundreds of millions of years and long-extinct volcanoes look as if they were venting only yesterday. This is the nature of Mars’ thin, cold atmosphere; erosional processes that rapidly delete Earth’s geological history are largely absent on the Red Planet, creating a smorgasbord of features that provide planetary scientists with an open book on Mars’ ancient past.

In this latest observation from the European Mars Express mission, a flood of biblical proportions has been captured in all its glory. But this flood didn’t happen recently, this flood engulfed a vast plain to the north of the famous Valles Marineris region billions of years ago.

It is believed that a series of volcanic eruptions and tectonic upheavals in the Tharsis region caused several massive groundwater releases from Echus Chasma, a collection of valleys some 100 kilometers (62 miles) long and up to 4 kilometers (2.5 miles) deep. These powerful bursts of water carved vast outflow channels into the adjacent Lunae Planum, contributing to the formation of the Kasei Valles outflow channels, releasing water into the vast Chryse Planitia plains which acted as a “sink.” Smaller “dendritic” channels can be seen throughout the plain, indicating that there were likely many episodic bursts of water flooding the region.

This context image shows a region of Mars where Kasei Vallis empties into the vast Chryse Planitia (NASA MGS MOLA Science Team)
This context image shows a region of Mars where Kasei Vallis empties into the vast Chryse Planitia (NASA MGS MOLA Science Team)

These floods happened between 3.4 to 3.6 billion years ago, less than a billion years after the most basic lifeforms started to appear on Earth (a period of time known as the Paleoarchean era).

In the middle of what was likely a powerful, vast and turbulent flows of water is Worcester Crater that was created before the Tharsis floods and, though its crater rim stands to this day and retains its shape, it was obviously affected by the flow of water, with a “tail” of sediment downstream.

ESA Mars Express observation of the mouth of Kasei Valles, as it transitions into Chryse Planitia. The large crater in the lower left is Worcester Crater. (ESA/DLR/FU Berlin)
ESA Mars Express observation of the mouth of Kasei Valles, as it transitions into Chryse Planitia. The large crater in the lower left is Worcester Crater (ESA/DLR/FU Berlin)

Also of note are smaller “fresh” craters that would have appeared long after the flooding took place, excavating the otherwise smooth outflow channels. These younger craters have tails that seem to be pointed in the opposite direction of the flow of water. These tails weren’t caused by the flow of water, but by the prevailing wind direction.

From orbital observations by our armada of Mars missions, it is well known that these channels contain clays and other minerals associated with the long-term presence of water. Although the Red Planet is now a very dry place, as these beautiful Mars Express images show, this certainly hasn’t always been the case.

ALMA Reveals the True Nature of Hubble’s Enigmatic Ghost Spiral

Appearing as a ghostly apparition in deep space, the LL Pegasi spiral nebula signals the death of a star — and the world’s most powerful radio observatory has delved into its deeper meaning.

Left: HST image of LL Pegasi publicized in 2010. Credit: ESA/NASA & R. Sahai. Right: ALMA image of LL Pegasi. Credit: ALMA (ESO/NAOJ/NRAO) / Hyosun Kim et al.

When the Hubble Space Telescope revealed the stunning LL Pegasi spiral for the first time, its ghostly appearance captivated the world.

Known to be an ancient, massive star, LL Pegasi is dying and shedding huge quantities of gas and dust into space. But this is no ordinary dying star, this is a binary system that is going out in style.

The concentric rings in the star system’s nebula are spiraling outwards, like the streams of water being ejected from a lawn sprinkler’s head. On initial inspection of the Hubble observation, it was assumed that the spiral must be caused by the near-circular orbit of two stars, one of which is generating the flood of gas. Judging by the symmetry of the rings, this system must be pointing roughly face-on, from our perspective.

Though these assumptions generally hold true, new follow-up observations by the Atacama Large Millimeter/submillimeter Array (ALMA) on the 5,000 meter-high Chajnantor plateau in Chile has added extra depth to the initial Hubble observations. Astronomers have used the incredible power of ALMA to see a pattern in the rings, revealing the complex orbital dynamics at play deep in the center of the spiral.

“It is exciting to see such a beautiful spiral-shell pattern in the sky. Our observations have revealed the exquisitely ordered three-dimensional geometry of this spiral-shell pattern, and we have produced a very satisfying theory to account for its details,” said Hyosun Kim, of the Academia Sinica Institute of Astronomy and Astrophysics (ASIAA) in Taiwan and lead researcher of this work.

Just as we read tree rings to understand the history of seasonal tree growth and climatic conditions, Kim’s team used the rings of LL Pegasi to learn about the nature of the binary star’s 800 year orbit. One of the key findings was the ALMA imaging of bifurcation in the rings; after comparing with theoretical models, they found that these features are an indicator that the central stars’ orbit is not circular — it’s in fact highly elliptical.

ALMA observation of the molecular gas around LL Pegasi. By comparing this gas distribution with theoretical simulations, the team concluded that the bifurcation of the spiral-shell pattern (indicated by a white box) is resulted from a highly elliptical binary system. Credit: ALMA (ESO/NAOJ/NRAO) / Hyosun Kim et al.

Probably most striking, however, was that Hubble was only able to image the 2D projection of what is in fact a 3D object, something that ALMA could investigate. By measuring the line-of-sight velocities of gas being ejected from the central star, ALMA was able to create a three-dimensional view of the nebula, with the help of numerical modeling. Watch the animation below:

“While the [Hubble Space Telescope] image shows us the beautiful spiral structure, it is a 2D projection of a 3D shape, which becomes fully revealed in the ALMA data,” added co-author Raghvendra Sahai, of NASA’s Jet Propulsion Laboratory in Pasadena, Calif., in a statement.

This research is a showcase of the power of combining observations from different telescopes. Hubble was able to produce a dazzling (2D) picture of the side-on structure of LL Pegasi’s spirals, but ALMA’s precision measurements of gas outflow speed added (3D) depth, helping us “see” an otherwise hidden structure, while revealing the orbital dynamics of two distant stars.

A special thanks to Hyosun Kim for sending me the video of the LL Pegasi visualization!

So it Could be a ‘Supervoid’ That’s Causing the Mysterious CMB ‘Cold Spot’

Only last month I recorded a DNews video about the awesome possibilities of the “Cold Spot” that sits ominously in the cosmic microwave background (CMB) anisotropy maps (anisotropies = teenie tiny temperature variations in the CMB).

I still hold onto the hope that this anomalous low temperature region is being caused by a neighboring parallel universe squishing up against our own. But evidence is mounting for there actually being a vast low density region — known as a “supervoid” — between us and that Cold Spot.

And that’s crappy news for my dreams of cosmologists finding bona fide observational clues of the multiverse hypothesis any time soon. The Cold Spot could just be the frigid fingerprint of this supervoid etched into our observations of the CMB.

But as this supervoid could be as wide as 1.8 billion light-years, this discovery is still crazy cool — the supervoid could be the newest candidate for the largest structure ever discovered in the universe. Suck it, Sloan Great Wall.

Read more about this new research published today in the Monthly Notices of the Royal Astronomical Society in my Discovery News blog.

“Chewie, We’re Home.”

Credit: Lucasfilm/Disney
Credit: Lucasfilm/Disney

I know that Star Wars lovers everywhere are currently on their nth replay of the brand new The Force Awakens movie trailer, and for good reason. BECAUSE IT IS JUST PURE AWESOMENESS.


There were tears.

I have nothing else to add, except, for the first time in my adult life I can’t wait til Christmas.

Keep hitting repeat. And again:

The Large Hadron Collider is Powering Back Up, What Next?

A segment of the Large Hadron Collider's super-cooled electromagnets. Credit: CERN/LHC
A segment of the Large Hadron Collider’s super-cooled electromagnets. Credit: CERN/LHC

After a 2 year hiatus for a significant upgrade, the Large Hadron Collider is being switched back on and, early on Sunday, the world’s most powerful particle accelerator saw the first circulation of protons around its 27 kilometer ring of superconducting electromagnets.

This is awesome news, especially as there was a minor electrical short last week that could have derailed this momentous occasion for weeks, or maybe months. In one of magnet segments, a metallic piece of debris from the upgrade work had become jammed in a diode box, triggering the short. Manual removal of the debris would have forced a lengthy warm up and then cool down back to cryogenic temperatures, but CERN engineers were able to find a quick fix — by passing an electrical current through the problem circuit the tiny piece of debris was burnt away, no warm-up required.

With this small hiccup out of the way, the complex task of circulating protons around the LHC began this weekend, resulting in two sparsely populated beams of protons speeding around the LHC in opposite directions. So far, so good, but the particle accelerator is far from being ready to recommence particle collisions.

“Bringing the LHC back on, from a complete shutdown to doing physics, is not a question of pushing a button and away you go,” Paul Collier, head of beams at CERN, told Nature News.

Sure, the LHC is circulating protons, but it is far from restarting high-energy collisions. In fact, over the coming weeks and months, engineers will be tuning the machine to finely collimate the counter-rotating beams of protons and gradually ramping-up their speed. The first collisions aren’t expected to begin until June at the earliest.

But seeing protons pump around the LHC for the first time since 2013 is an awesome sign that all the high-energy plumbing is in place and the electrical backbone of the accelerator appears to be working in synergy with the massive magnetic hardware.

Over the next 8 weeks, engineers will turn on the LHC’s acceleration systems, boosting the beam energy from 450 GeV to 6.5 TeV, gradually focusing the beams in preparation for the first collisions.

According to Nature, the re-started LHC will slam 1 billion pairs of protons together every second inside the various detectors dotted around the accelerator ring with a collision energy of 13 TeV, boosting the LHC’s energy into a whole new regime. During the LHC’s first run, the maximum energy recorded was 8 TeV.

This makes for a curious time in cutting-edge particle physics.

Before the LHC was fully commissioned in 2008, its clear task was to track down, discover and characterize the Higgs boson, the last remaining piece of the Standard Model. Having achieved the Higgs discovery in 2012 — resulting in the 2013 Nobel Prize being awarded to Peter Higgs and François Englert — physicists have been combing through the reams of data to understand the new particle’s characteristics. Although a lot still needs to be learnt about the famous boson that endows all matter with mass, Run 2 of the LHC has a rather vague mission. But “vague” certainly doesn’t mean dull, we could be entering into a new era of physics discovery.

I always imagine that powering up the LHC is like this... completely inaccurate, mind you.
I always imagine that powering up the LHC is like this… completely inaccurate, mind you.

We’ve never seen collision energies this high before, and with the Standard Model all but tied up, physicists are on the lookout for phenomena with an “exotic” flavor. Exotic, in this case, means the production of quantum effects that cannot be easily explained or may be driven by mechanics that have, until now, been considered pure speculation.

Personally, I’m excited that the LHC may generate a signature that we cannot explain. I’m also trilled by the possibility of micro-black holes, the discovery of dark matter particles, potential hints of supersymmetry and quantum gravity. But I’m doubly-thrilled by the prospect of something popping out of the collision debris that doesn’t make any sense.

As the LHC will now slam protons (and, later, ions) at energies nearly double of what it was previously capable of, we are in uncharted territory. Physicists are recreating the conditions of the Big Bang, condensing primordial particles and forces from the concentrated energy of colliding beams of charged particles. So far, after only 7 years since the LHC was first powered up, it has already confirmed the existence of a Standard Model Higgs boson. So now, without a single ultimate goal, the LHC will do what physics does best, discovery-driven science that could answer many quantum mysteries and, hopefully, create many more.

Battlestar Galactica’s “Twelve Colonies of Kobol” Star System Found?

An image at radio wavelengths of a young stellar quadruplet. Credit: CfA/Nature/Pineda
An image at radio wavelengths of a young stellar quadruplet. Credit: CfA/Nature/Pineda

825 light-years away, in the constellation of Perseus, hides one protostar and three previously unseen gas concentrations that are undergoing gravitational collapse — basically embryos of soon-to-be baby stars. Found through the analysis of data from radio telescopes by astronomers at the Harvard-Smithsonian Center for Astrophysics (CfA), this tiny cluster of baby stars occupy a small volume only 10,000 AU across — meaning that they’d all easily fit within the confines of the boundaries of our solar system (yes, the Oort Cloud is the solar system’s outermost boundary).

This is exciting for a couple of reasons. Firstly, this little ‘stellar womb’ has given astronomers an opportunity to study the genesis of a multi-star system. Indeed, most stars in our galaxy belong to multi-star systems, whether that be binary or greater, and astronomers are currently trying to figure out whether they were born this way or whether, over time, stars jostled around and eventually became gravitationally bound. After analysis of the velocities of the protostar and stellar embryos, it appears that the masses are gravitationally interacting. In other words, it has the potential to mature into a quadruple star system in around 40,000 years, a minute amount of time in cosmic timescales. Although it is likely that the system will become unstable, possibly ejecting one or two of the stars in the process, it does provide observational evidence that multi-star systems can be born in a gravitational embrace.

A map of the Twelve Colonies via
A map of the Twelve Colonies via

But as I have a habit of linking astrophysical studies with science fiction imaginings, when I first saw this research, I immediately thought of the awesome re-imagined series’ Battlestar Galactica and Caprica.

Battlestar Galactica is set in the years following the Cylon attack on the Twelve Colonies of Kobol, which almost wiped out humanity in this far-flung part of the galaxy. The remaining survivors, headed by William Adama (Edward James Olmos), take to the stars in a fleet of ragtag spaceships in search of the fabled Earth. One of my favorite scifi storylines and favorite scfi TV shows. But I digress.

The Twelve Colonies consist of four stars — Helios Alpha, Helios Beta, Helios Delta and Helios Gamma — each with their own systems of planets, 12 in total, including capital world Caprica.

So that poses a question: Just because Battlestar Galactica imagines a quadruple star system (well, two binary systems in a mutual orbit), is it possible to have such a stable system of planets evolve in a multi-star system? Or are the gravitational interactions too complex for anything to coalesce and slot into stable orbits? Well, by understanding how multi-star systems evolve by finding examples like this embedded inside star forming molecular clouds, we may start to appreciate how common and how stable they are and whether accompanying planetary systems are a reality or something that will forever be confined to the Twelve Colonies.

READ MORE: Star Quadruplets Spied Growing Inside Stellar Womb (Discovery News)

On Mars, There’s No Asphalt

Curiosity's right-middle and rear wheels, bearing the scars of 488 sols of rough roving. Credit: NASA/JPL-Caltech
Curiosity’s right-middle and rear wheels, bearing the scars of 488 sols of rough roving. Credit: NASA/JPL-Caltech

If you’re like me, you hang off every news release and new photo from our tenacious Mars rover Curiosity. The awesome one-ton, six-wheeled robot is, after all, exploring a very alien landscape. But if there’s one thing I’ve learned from the mission, Mars is far from being a truly alien place. Sure, we can’t breath the thin frigid air, but we can certainly recognize similar geological processes that we have on Earth, and, most intriguingly, regions that would have once been habitable for life as we know it. This doesn’t mean there was life, just that once upon a time parts of Gale Crater would have been pretty cozy for terrestrial microbes. Personally, I find that notion fascinating.

But, way back in May, I noticed something awry with our beloved rover’s wheels. Curiosity’s beautiful aircraft-grade aluminum wheels were looking rather beaten up. Punctures had appeared. Fearing the worst I reached out to NASA to find out what was going on. After a friendly email exchange with lead rover driver Matt Heverly, I felt a lot more at ease: The damage was predicted; dings, scratches, even holes were expected to appear in the thinnest (0.75 mm thick) aluminum between the treads. On Mars, after all, there is no asphalt. Also, erosion is a slower-paced affair in the thin winds and dry environment — sharp, fractured rocks protrude, embedding themselves into the wheels at every slow turn.

Then, on Friday, in a news update on Curiosity’s progress, JPL scientists mentioned that they would be commanding the rover to drive over a comparatively smooth patch to evaluate the condition of the wheels as their condition is getting worse. But isn’t that to be expected? Apparently not to this degree. “Dents and holes were anticipated, but the amount of wear appears to have accelerated in the past month or so,” said Jim Erickson, project manager for the NASA Mars Science Laboratory at NASA’s Jet Propulsion Laboratory, Pasadena, Calif.

So what are we looking at here?


All of the wheels are exhibiting wear and tear, but this particular ‘rip’ in aluminum is by far the most dramatic. But what does that mean for Curiosity? We’ll have to wait and see once JPL engineers have assessed their condition. Although this kind of damage has inevitably been worked into the the structural equations for the wheels’ load-bearing capabilities, whichever way you look at it, damage like this is not good — especially as Curiosity hasn’t even roved three miles yet.

But in the spirit of Mars exploration, Curiosity will soldier on regardless of how rough the red planet treats her.

Read more in my coverage on Discovery News, a location you’ll find me during most daylight (and many nighttime) hours:

Jovian Joviality: Juno is a Healthy Spaceship, On-Track for 2016 Jupiter Rendezvous

Artist's impression of the Juno flyby (NASA)
Artist’s impression of the Juno flyby (NASA)

Last week’s Juno flyby of Earth was an exciting event. NASA’s Jupiter-bound mission buzzed our planet on Wednesday (Oct. 9) only 350 miles from the surface, providing amateur astronomers with an opportunity to snapshot Juno as she flew past, stealing a little momentum from Earth and sling-shotting toward the largest planet in the Solar System. Alas, the flyby event wasn’t without incident.

The spacecraft dropped into “safe mode” shortly after its terrestrial encounter. Safe mode is a fail safe on spacecraft that protects onboard instruments from an unexpected condition. This can come in the form of a power spike or some other instrumental error. It is not known at this time what triggered this particular event, but the upshot is that Juno is back in its nominal state.

From a Southwest Research Institute news release:

“Onboard Juno, the safe mode turned off instruments and a few non-critical spacecraft components, and pointed the spacecraft toward the Sun to ensure the solar arrays received power. The spacecraft acted as expected during the transition into and while in safe mode.”

Juno’s planned trajectory was not impacted during the flyby and it is expected to make orbital insertion around Jupiter in July 2016.

The mission was launched from Cape Canaveral, Fla., in 2011 and, through a wonderful bit of orbital mechanics, was commanded to do one 2-year orbit around the Sun. Then, last week, it ended up where it started to use our planet as a speed booster, flinging it further out into the Solar System toward Jupiter’s orbit. This acceleration “freebie” was needed as the launch vehicle, an Atlas V rocket, didn’t have the oomph to propel the spacecraft deeper into space.

Once Juno arrives at Jupiter, it will give the gas giant a thorough full-body examination, investigating what lies beneath its clouds, how it generates its powerful magnetic field and how it evolved. The repercussions of Juno’s one-year primary mission will hopefully expose not only how Jupiter is formed, but how Earth evolved into its current state.

As Juno sped past on Wednesday, I allowed myself an early celebration of some fine flying by NASA scientists with a Gin & Tonic (or a Juno & Tonic) in my special JPL-bought Juno glasses.

Good luck Juno, will look forward to seeing you at Jupiter in a little under three years time!

MORE: Read my Discovery News post about the possibility of Juno exhibiting the mysterious “flyby anomaly.”