Life on Titan? A new paper looks at the evidence and ideas....

Above: An artists impression  of Titan's strange surface

Saturn's largest moon, Titan, is a very strange place where some very strange things are happening: Methane lakes, magic islands, chemical imbalances, plasti-karst landscapes, prebiotic snow, and methane rain are just a taster of what this weird, frozen-yet-active, moon has to teach us. But there's a big question we'd like to answer even more: Could this weird moon harbour life - or at least something equivalent to life, for an environment hundreds of degrees below freezing where it rains methane?

Above: Titan's lake district, as seen through the Cassini space probes infra red camera. Courtesy of NASA.

A study from Christopher Mackey, at NASA's Ames Research Centre, has been released to give the world a view on where we are when it comes to answering that question. I'll quote part of the conclusions below. The paper itself is free to download here.

"....it may be that if there is life in the liquids on Titan’s surface it may be simple, heterotrophic, slow to metabolize, and slow to adapt with limited genetic and metabolic complexity. The simple molecules needed for metabolism may be widespread in the environment and in the methane/ethane liquids, but the complex organics needed for structural or genetic systems may be hard to obtain or synthesize. The communities formed may be ecologically simple—perhaps analogous to the microbial ecosystems found in extreme cold and dry environments on Earth.
... Titan may have only a simple trophic system, probably without primary producers and without predators. Photosynthesis may be beyond the complexity that can be achieved with the limited element and hence genetic diversity—and food should be free. The simple low temperature life forms and communities envisaged would have very low energy demands and would grow slowly. Life on Titan may be not much more than auto-catalytic reactions encased in azotomes. However, if it had genetics, and were thus Darwinian, then what a wonderful life it would be: a second genesis different enough from Earth life to suggest that our Universe is full of diverse and wondrous life forms.
In terms of ethical considerations, the search for a second genesis of life on Titan contrasts with the similar search on Mars. On Mars, issues of contamination both with respect to the Martian environment and back contamination of the Earth are important concerns. Furthermore, it has been suggested that if there were a second genesis of life on Mars the global conditions are not favorable for it and humans may choose to intervene to improve them [62]. In contrast, possibilities of contamination of Titan with water-based life from Earth are essentially zero, as are the possibilities for back contamination of the Earth with life from Titan."

So, basically, we don't know enough to call it yet - but if there is some form of alien life there it is likely to be both primitive and truly unique from life on Earth.

That sounds like a world worth going back for a second look at.....

Elsewhere in the Universe:
Huge meteorite explosion off the coast of Brazil
SpaceX aborts rocket launch
Could gravitational waves be used in an FTL engine? 
Narrowing the hunt for planet 9 

Moon base ahoy?

I've been posting a lot on the Moon recently but, well, it's the nearest world to us and it's just out my window at the moment - so I'll round off the week (I'm travelling tomorrow and Monday so the next post will be Tuesday) with one last Moon related post:

Yes, this is a post about Moonbases.

Whenever someone uses the phrase ' Moonbase' I get very sceptical*: The ISS took a dozen nations ten years and hundreds of billions to build, and it's a historical fact that it happened almost more by good luck than political will. So I tend to assume Moonbase ideas are a good way to get a soundbite and drum up some publicity, and not a lot more. 

Above: ESA's pans for a 'Moon Village'. Courtesy of ESA.

But ESA's new head is on record as being fully behind the idea, and NASA is planning to give the Moo it's own moon in the coming decade, not to mention all the upcoming lunar interest I mentioned in this post earlier. I'm not able to put these directly into the blog, but it's well worth following the links: Firstly, the 'boss' of ESA, on plans to build a Moon village:

Link here

Second, an astronaut's views on the same idea:

Link here

So.. maybe... just maybe... 

* Almost as skeptical as I get when I hear the phrase 'Boots on Mars'.

Gorilla in space!

Gorilla goes wild on space station:

OK, the title isn't entirely accurate. This all began with the question: "What do you send, as a present, to a crewman on the ISS?" For reasons best left unexplored, someone came up with 'gorilla suit' as an answer, and this was the result:

 

It's a busy day, but I could hardly resist posting that, could I?

Does the Moon sing?

Above: A map of the Moon's residual magnetic field. Could it be connected to the strange radio signals? Courtesy of NASA.

There's been a story circulating about mysterious sounds - sometimes described as music - that were heard over the radio by the crew of Apollo 10 as they circled the Moon. Similar sounds were reported by other astronauts orbiting the Moon, but their origin is a complete mystery. Have a listen:

It wouldn't be a total surprise if the Moon did produce some sort of structured, or 'musical' noise at radio frequencies. A lot of the worlds we've visted - even really tiny ones like comets - produce radio frequency 'songs'. 
The songs have various origins: The vibrations of charged particles within the worlds structure, charged particles coming from them, or the solar wind hitting a worlds magnetic field are a few of the most common. The Moon has some areas with a residual magnetic field, so perhaps that's the explanation.

Here're are few of the radio wave 'songs' played by various worlds. See what you think - does it sound like music to you?

Elsewhere in the Universe:
Virgin Galactic looks to establish safety culture
China aims to land rover on Mars
Earth may be rare after all

All about the Moon

Above: The Apollo 15 mission on the Moon.

It's there, just over there, visible most of the time. It's the Moon - a world as big as some planets - and even though we once landed people there, many years ago, we haven't solved it's mysteries. And there are a lot of them: From how long it had an atmosphere, to whether it still has volcanic activity, to where the massive polar reservoirs of water ice and organic molecules came from. The Moon still has a lot that needs exploring, and can tell us about Earth's ancient history.

Above: An artists impression of lunar ice in a permanently  shadowed valley.

Luckily there are people on the case: China has sited a UV observatory there, NASA is ending missions to explore it's poles, and the next few years should see private missions on their way...

Chang'e lives on:
The Chang'e 3 lunar lander / UV observatory is celebrating its 28th Lunar day, on a mission that began with this landing...

Yutu stays silent:
There's no word on Yutu, the lunar rover that started out from the belly of the Chang'e lander and became stuck due to a mechanical malfunction. However, even disabled, Yutu's sensors did sterling work, returning mountains of images and data, and forcing us to re-evaluate theories of Lunar geology.

Above: Yutu sets out onto the Lunar surface.

China plans to land another robot, this time on the far side of the Moon:
The lunar far side is still a mystery, not just because it cannot be seen from earth: it' has few of the dark basalt plain that make the dark areas on the face of the Near side. the lunar crust there is thicker, and has piled up into endless highlands of pale anorthosite rock - and although many explanations have been pout forwards for this difference, none has yet been definitively proven.

The Lunar desert gets busy:
China aren't the only ones looking to the Moon: The Google Lunar x prize is a competition to see if anyone can land a privately funded robot on the lunar surface, and have it send back video. Two teams are set to try for a private Moon landing: Space IL and Moon Xpress will share a launch in 2017.

NASA goes into the eternal shadow:
Lunar flashlight is one of new breed of spacecraft: One of the first probes to another world that is built around the modular 'cubesat' technology for ultra-small space craft. It will launch in 2018, and shine infra red lasers into the permanently shadowed regions of the lunar poles, and look for water ice as well as many other volatile materials.

Above: Concept art from NASA.

Elsewhere in the Universe:
Stephen Hawking wants to ride SpaceShipTwo
NASA works on laser powered space drive

Charon, an ocean world?

Pluto's moon Charon may have had an ocean.

The New Horizons probe has blown the science world away by revealing Pluto, in all its cold-but-strangely-active strangeness, to us. But Pluto wasn't the only world New Horizons visited that day: The dwarf planet has five moons and the largest of them, Charon, is turning out to be a fascinating little critter in its own right.
The little moon sports all kinds of weird features: Craters that have dug into an ammonia rich layer, a strange dark polar cap, and gigantic chasms and tectonic features to point out just a few.

Above: A simulated fly by of Charon, showing the vast network of chasms and the dark polar cap. Courtesy of IO9.

Now a picture is starting to form for researchers studying the New Horizons data on Charon. The little moon may well once have had a subsurface ocean, like the moons Europa and Enceladus. The evidence comes from the network of fractures and faults that scar the Charon's surface: One possible explanation for them is that as an interior ocean froze it expanded (because water expands when it freezes), and cracked the outer shell of the moon apart. 
Other lines of evidence point towards an ancient ocean too, like the mysterious ammonia rich crater: Ammonia is a potent antifreeze, and as the ocean froze the ammonia would have become more and more concentrated, as it kept an ever shrinking pool of liquid from freezing. When it finally froze completely the ice that formed would be loaded with ammonia crystals.

All of which raises an interesting question: Was it an ocean that could have supported life, out on the edge of interstellar space?

The top portion of this image shows part of the feature informally named Serenity Chasma.
The lower portion of the image shows color-coded topography of the same scene. Measurements of the shape of this feature tell scientists that Charon’s water ice layer may have been at least partially liquid in its early history, and has since refrozen. Caption and image courtesy of NASA.

Watch a space ship being built in time lapse:

Virgin galactic have been busy little beavers, putting together an updated version of their SpaceShip 2 sub-orbital vehicle. Despite the tragedy of a fatal accident during a test flight, the company seems to be hauling itself back. As well as this, they've announced that they will be running orbital flights, for smallsats using their Launcher 1  space rocket. Enjoy!

All about Mars.....

To find life on Mars, follow the salt:

Above: Streaks on martian slopes, believed to be due to brine water.

At present our exloration of Mars has focussed on parts that saw habitable - which means watery - environent in the ancient, ancient past.

But that might not be the best way to find evidence of life: Mars took aeons to die, and any life there would have evolved to protect itself - and it might have followed the same adaptation processes organisms on Earth have for extreme dryness.
That'd mean the right tactic to find it would be following salt, not water, according to Dirk Schulze-Makuch, an astrobiologist at Washington State University.
"There is a predictable sequence of how organisms adapt to increasing dryness," he  told Space.com.
Eventually microbes seem to hit on the trick of living inside layers of salt crystals - particular types of salt will suck moisture out of even Mars-dry air and form brine water. Liquid brines within salt crusts might have served as the last available habitats for life near the Martian surface, Schulze-Makuch said  In fact, in this way Martian life might have survived to ths day


Ordnance Survey releases Mars map

OS is brand of map very well known to anyone who has gone hiking in the UK - at least, if you've been serious about not need the mountain rescue guys. Their maps have been a staple of woodland and mountain explorer's backpacks for decades.  Now they're going where few mappers have gone before, and released a map of the planet Mars! Are they telling us that some of the backpaths in the Peak District lead to much further afield than we thought? That would explain the odd missing backpacker.... 


Fungi survive Mars conditions for 18 months  

The McMurdo Dry Valleys, located in the Antarctic Victoria Land, are considered to be the most similar earthly equivalent to Mars. They make up one of the driest and most hostile environments on our planet - most of the time it's too harsh even for snow to fall. Only microorganisms, capable of surviving in cracks in rocks, grow there - and only very slowly. But these hardy critters may have the stuff to survive in a harsher environemnt still: Mars. On the international space station, samples antarctic microbes were exposed to Martian conditions for 18 months... and nearly two thirds of them have survived.

Elsewhere in the Universe:
Possible second gravitational wave source detected
'Turborockets' 
 

Miniature spacecraft to set sail on full sized missions by the decade's end.

Above: Three cubesats being launched into space from the International Space Station.

Miniaturisation of electronics was the thing that made computers the massive turning point of the twentieth century. Now a lot of space enthusiasts are hoping that miniaturisation could be the next big revolution in space travel - and it's already looking like it might be: Over the last ten to fifteen years cubesats, thumbsats, and other miniature-and-affordable spacecraft have become a thriving niche market for doing science, such as testing new space drives,  in Earth orbit.

Above: The Lightsail-A solar sail testing cubesat.

Thanks to all the advances made in spacecraft miniaturisation cubesats are about to start flying into interplanetary space. In fact 13 cubesats will be travelling to Moon with the first launch of NASA's up and coming SLS rocket. The Near Earth Asteroid Scout will fly by solar sail propulsion (which was recently tested on a cubesat) to an asteroid, the MARCO cubesat's are travelling to Mars, and the Lunar Flashlight mission will map the poles of the Moon for water ice.

The future of space travel has room for both huge manned ships and tiny unmanned probes, but both are growing out capabilities in space - and I wonder where that will lead us?

Possible (and I can't emphasise that word enough) evidence of ancient bacterial activity on Mars

Above: A comparison of the 'micro-digitate' structures, on Earth and Mars. Courtesy of NASA.

An interesting theory has been put forward in a paper presented, at the 2015 AGU fall meeting. Titled " Micro-digitate Silica Structures on Earth and Mars: Potential Biosignatures Revealed in the Geyser Field of El Tatio, Chile", the gist of it is this: Certain types of volcanic spring produce deposits of silica round their edges. Those deposits can take on these strange 'micro digitate' structures, for no really obvious reason - and the paper has an explanation that could lead us to evidence of bacterial life on Mars: The 'digitate' structures are due to the action of bacteria,  growing in the forming deposits.
If these weird looking structures did form through microbial action it would be big news for the search for Martian life, because the extinct 'home plate' geothermal spring which was surveyed by the Spirit Mars rover.  The abstract is here, and Universe today has done a nice in-detailed breakdown of the theory here.

Gravitational waves and floating hills..

Isn't this typical: I go on holiday for a week and everyone starts making mind bending advancements in astrophysics and space technology,while you're stuck up in the Scottish highlands with the amazing mountains, wildlife, and ski slopes....

Yeah, Scotland you suck, and you're ugly too....

.... fair enough, I had a good holiday and I'd recommend Scotland to anyone who likes holidays that are bit more adventurous than just lying by the pool. But some of the things that have happened this week have been momentous, so lets have a quick look at the two stories that really caught my eye, before it's back to business as usual:


Gravitational wave detection:

This is the weeks big BIG news, and everyone says so. Lots of them then ask 'what the hell are gravitational waves' and they're right to do so, since this isn't a topic that's covered in high school physics. Which is odd, because it's actually very simple. Waves occur in lots of things: Sound waves in gasses, surfable waves in water, electromagnetic waves (like radio waves and light waves) in electric and magnetic fields. Gravitational waves are just waves in space itself.

A sound wave is a pressure wave, so as it passes you the air pressure gets higher, then lower. Ocean waves are up /down motions in the water,so as they pass the water gets higher, then lower. Gravitational waves are distortions in space-time, so as they pass space itself stretches and squashes. As one hits you, you get slightly taller and thinner (very, very slightly), then slightly shorter and fatter (Universe today has some good animations explaining them, here).

Above: If you looked at a ring of dots just as a really huge gravity wave passed through them, you'd see them flex like this.

Space-time itself rings like a bell and, thanks to the fact that all waves have some things in common, we can actually translate the gravitational waves into audible sounds....

Above: The gravitational wave signal seen by LIGO, converted into audible sounds. It sounds rather nice for something that's travelled across a billion light years. Courtesy of Georgia Tech.

The waves are incredibly tiny: The ones that were picked up had travelled over a billion light years, and by the time they hit earth they were only strong enough to distort space by about 1/10,000 of the width of a hydrogen atom. But the incredibly sensitive detectors built to detect them, the LIGO detectors, independently saw the signal at the same time, which is a good sign that this is a real detection (and the reason why two detectors were built in the first place)

What does all this mean, aside from being a scientific curiosity? 
It gives us an entirely new way of 'seeing' the universe, other than electromagnetic waves (like light) and particles - in principle we can now see through light years of gas and dust, and watch the most powerful events in the history of the universe. the signal that was picked up was from two black holes, each weighing tens of times more than the Sun, hitting into each other...

Above: A simulation of what the event seen by LIGO would look like close up, courtesy of SXS Lensing

But it's also a final confirmation of Einstein's theories of gravity - confirming that they were on the money, in almost every respect, as far as we can measure.


Floating hills on Pluto:

Above: The clusters of floating hills on Pluto's sea of glaciers. Courtesy of NASA.

Last year the New Horizons spaceship gave us our first close up view of the dwarf planet Pluto. One of the surprises it gave us was the discovery of Sputnik Planum, a vast 'sea' of nitrogen ice glaciers. On Earth glaciers are made of water ice, which seems solid enough but flows at large scales. That allows huge 'rivers' of ice to flow across the plains of Antarctica and down the sides of mountains. On Pluto water ice is far too hard to flow at all, because of the much lower temperature. But nitrogen ice is still squishy enough to form glaciers in such frigid conditions - and unlike the isolated glaciers of Earth, Pluto's flow into a huge sea of slightly squashy nitrogen ice. 

That sea does some things we don't entirely understand, like form huge cell-like patterns on its surface (probably due to very slow convection currents), and elliptical pits that all line up.

Above: The cell-like patterns on the surface of Sputnik Planum

Now a detailed study of the latest images to be transmitted home by New Horizons has shown that it does something else: It actually has hills that float on it!
On Pluto the hills are made of water ice frozen super-hard. But it's still water ice, and water ice is less dense than nitrogen ice, so whole hills have broken off from the coastline if Sputnik planum and gone floating away, a bit like a bizarre reflection of Earth's ice bergs:

The hills are gathered in clusters at various spots, and seem to drift on the glaciers until they run aground somewhere.... or wander the sea forever. But this is all pretty day to day for the New Horizons team - I can't wait to hear about Pluto's next weird surprise!

Elsewhere in the universe:

James Webb Space Telesope passes milestone

Massive rogue planet found

Goodies from the Chinese Moon lander Change' and rover Yutu.....

Above: Yutu sets off into the lunar wilderness.

I'm away for the coming week, so there'll be no posts until next Friday at the earliest. But before I go I'll leave you with one of these that ideas I love because of how simple yet effective it is.

50 Years ago on Wednesday humanity got its first pictures back from unmanned probes sent to the Moon. The most recent landings there were the Change lander/ unmanned observatory, and the Yutu rover - and the Chinese space agency has released a whole bunch of new pictures from the ongoing mission.

Above: Yutu does Change' a farewell doughnut.

The Yutu rover took a panorama, as a series of pictures, of it's landng site on the Moon, the Change lander/lunar observtory, and the landmarks  around it. 

These have been very skiillfully stitched together by Justin Cowert from unmannedspacecom, to give the full panoramic viw of the Moon's black sky and razor edged horizon. All an amazing feat all on it's own, but then it was taken up a notch when it was uploaded to RoundMe (here), a website that specialses in presenting all sorts of panorama's in a very unique way. 

And in this case it may be the closest you'll ever get to knowing what it's really like to stand on the Moon....

Elsewhere in the universe:

Luxemburg supporting space mining

NASA satellites investigate dmage patterns in Nepal

A flight over Ceres!

Above: Occator crater with its mysterious bright patches. Courtesy of NASA.

The Dwarf planet Ceres is known to space exploration as king of the asteroids - and, now that the Dawn space probe has begun exploring it in earnest, as a world that throws up two mysteries for every one that is solved: From the strange bright patches and volcanic looking terrain, to totally unexpected mists over Occator crater, to chemical evidence suggesting it might be an immigrant from the cold outer solar system, Ceres seems determined to both surprise us and keep its secrets as long as it can.

Above: A size comparison between Ceres, Earth, and the Moon.

And long it may keep them, as this small and distant wold is unlikely to be visited by humans for many decades at least. But this week Dawn's framing camera team at the German Aerospace Center, DLR, gave the whole world a brief taste of what being on such a mission might be like, when they released this high quality simulation, based on Dawn's data, of a flight over Ceres:

The virtual flight path was picked to give an impression of how the Cerean terrain changes from place to place."The simulated overflight shows the wide range of crater shapes that we have encountered on Ceres. The viewer can observe the sheer walls of the crater Occator, and also Dantu and Yalode, where the craters are a lot flatter," said Ralf Jaumann, a Dawn mission scientist at DLR.

How the Moon influences the weather

The Moon influences the tides, controls the length of the day, controls the biological cycles of certain creatures, and of course, werewolves*. But, for the first time, it has been shown by Tsubasa Kohyama and John M. Wallace that Earth's nearest neighbour can exert control ovr the weather. Specifically their investigations have found that the Moon influences rain fall, in a small but definite way. "As far as I know, this is the first study to convincingly connect the tidal force of the moon with rainfall," said Kohyama.

Yep, you an now literally blame he rain on the Moon. Well...one drop in every hundred, at least.

The way it works is down to gravity, and is not a million miles away from ow tides work: When the Moon is overhead, its gravity causes Earth's atmosphere to bulge toward it, like a tide of air, so the pressure of the atmosphere on that side of the planet goes up. Higher pressure increases the temperature of air near the surface. Since warmer air can hold more moisture this makes rain - which happens when the air has too much water - harder to form.

Filled to capacity.....

The effect is measurable, but, today, very small. "No one should carry an umbrella just because the moon is rising," Kohyama said.The effect could be used to test climate models, checking if they're good enough to reproduce how the pull of the moon eventually leads to less rain. A further twist to the tale is how this might change our understanding of ancient Earth: In ancient times The Moon was closer, and raised more powerful tides - becoming truly monstrous if you go back far enough. Would the dinosaurs, for example, have been able to predict some aspects of the weather based on the Moon's stronger influence? We may never know, but now the idea has been raised researchers will be looking for ways to find out. 

Above: I'm not sure T-rex would have cared very much... but you never know......

Even today the Moon may be pivotal in easily influenced weather systems. Wallace plans to study the Moons' meteorological effects further: Some categories of rain may be more susceptible to the influence of the Moon, and the frequency of rainstorms may show a lunar connection.

Maybe what's out there has more of an impact down here than we ever realised...

Liquids on Pluto, its huge climate changes, and NH next target....

Recently Alan Stern spoke to the SBAG about the latest New Horizons plans (latest Adobe version needed). Alan is New Horizon's principle investigator (basically he's the closest thing an unmanned probe gets to a captain), Alan Stern. I was hoping to put up a youtube version of this talk, but the only version I can get my hands on needs the latest version of Adobe (gettable from here). For those of you who don't or can't get Adobe, here're the highlights of the talk, with some stills:

• This was the first detailed presentation that includeds extended mission plans, and results to date put into context.
• New Horizons carries 7 instruments (link to more info here), and is RTG powered.

• PEPSSI and SWAP instruments made important detections, there's a paper about it submitted to science magazine.
• The dust detector will be the first to take readings out to 35 AU and kuiper belt
• 16 months to beam all data back (4 months if they had the dsn to themselves)
• They got good data on all of daylight Pluto, not just the side that got imaged at closest approach:
• Black and white optical data of far side at 40km per pixel resolution.
• UV and colour data, with 200 km footprint, of the far side - good enough to do regional colour and composition analysis.
• The best resolution of encounter hemisphere is 70m/pixel.

Above: All the sunlight views of Pluto. Only the south pole was never seen due to permanent darkness.

• New horizons has revealed a very complex world
• Young icy plains - especially the glacier sea of Tombaugh regio.
• Sublimation pits in the glaciers
• Dark, very red, plains devoid of volatiles
• Tectonic features: Scarps, faults, and rift valleys.
• What look like shield volcanoes
• A complex atmosphere

• The atmosphere shows:
• Possibly evidence of huge pressure pulses on the surface, from near zero millibars up to 100 millibars of atmosphere (more on that below)
• 24 plus haze layers, probably made of tholin particles, up to 230 km height.
• Very similar to Titan's extended/detached haze layers
• They're blue in colour ,as seen from behind the planet via scattering via Raleigh scattering. 

• The scattering is so bright the NH team can use the hazeshine to see the night side at high resolution, and are mapping large areas that way- an unexpected bonus!

• Atmosphere is colder, and more compact, than expected - this result is from the by solar UV occultation experiment.

Above: The results of the solar UV occultation test.

• Atmosphere loss rate is 1000 to 10000 times lower than expected - much more like a planet than a comet, which was the expectation..

• A false colour, dynamically stretched, view of the surface shows....

Above: A false colour, colour sharpened, view of Pluto.

• Red stuff (almost certainly organic) fills the mountains around glacier sea.
• The glacier sea fills an ancient impact basin
• The mountains are water ice, and are chaotic in structure; They seem to float on an ocean of frozen nitrogen.
• The mountains have snowcaps of methane.

False colour close up.

• The glacier sea has no craters (so it's under 10,000,000 years old.
• It has a 'cellular' pattern on its surface.

• This pattern is most likely due to convection in the ice (it's warm at bottom, like boiling syrup or a lava lamp)
• The glaciers are active, not preserved, and are seen to flow around obstacles
• Pluto seems to have , or have had, a Nitrogen cycle like Earth's water cycle
• The southern glaciers have pits:

Above: Pits in the glaciers

 

• Some pits are 100 meters deep or more, and show very, very, black matter at bottom.
• The pits have possibly have eaten through into a layer below the glaciers.
• Dendritic channels on the surface MAY indicate that liquids flowed on Pluto's surface in the past

Above: Dendrite channels.

 

• This would be evidence of huge pressure pulses on the surface, from near zero millibars up to 100 millibars of atmosphere.
• Shield volcanoes on surface, 100km wide, with very few craters on surface, indicating they are under a billion years
• Pluto has young, old, and middle age terrains - which means Pluto has been active throughout its history - where's the energy coming from on such a small, cold, world?
• Charon may have stolen atmosphere from Pluto during high pressure pulses, freezing it into dark polar cap
• Charon also shows a complex geologic history
• Organa crater on Charon has an ammonia ejecta blanket, possibly indicating subsurface fluids at one point.
• Several of the little moons look like two objects merged:
• The next target didn't get a name because Jim Greene dragged his feet getting the naming contest going, so it's called (informally) 'Jim Greene'
• It's under 50 km wide
• NH will arrive there on the1st Jan 2019
• NH will come close enough to do science on 20 KBO's

• NH will measure the heliosphere phenomena much better than Voyager.
• After Jim Greene flyby Nh may go into astrophysics mode - seek microlensing events from extrasolar planets, and doing dust studies..
• Here are the preliminary science objectives for Jim Greene: