Baltica

Despite my confusion over the location of ‘the Baltic States’, they are right where normal people would expect them; along the Baltic Sea. Somehow, over the years, my mind had decided that the otherwise-un-named Baltic states were located immediately north and northwest of Greece. However, I looked them up (for the sake of this blog), and boy, was I wrong. I had put these states in Eastern Europe, but way too far south.

The Baltic States (Estonia, Latvia, and Lithuania) are in Eastern Europe, snuggled up east of the Baltic Sea and west of the Ural Mountains of Asia. And that places them right on the protocontinent of Baltica!

So, yes, this is kind of related to the Supercontinents blogs, but I’m only going to explore this one little piece of crust. Sometimes it roamed around on its own. At other times, it gathered together with other pieces of crust. Right now, it is smooshed between NorthEastern Europe and NorthWestern Asia. Will it succumb and eventually be pushed under these larger plates, or will it somehow break free again? I don’t know. But let’s see what is known about it.

The thick core of Baltica is also known as the East European Craton and is more than 3 billion years old.

About 2 billion years ago, small pieces of crust started colliding. These included Sarmatia (which was the Ukrainian Shield and Voronezh Massif*) and Volgo-Uralia. That seemed to work pretty well, so about 1.8 billion years ago, they added Fennoscandia, which included the Baltic Shield.

Now, if I’m reading the articles right, about 750 million years ago, Baltica and Laurentia (most of North America) both rotated clockwise, bumped each other lightly and headed for the south pole. At some point (possibly 650 million years ago), it is postulated that Earth became completely covered in snow and ice. (Yes, Snowball Earth.)

It turns out that Siberia was located fairly close to the South Pole, too, and it apparently didn’t take long for Siberia to completely lose its cool. According to one theory, Siberia started having some severe volcanic eruptions, and the build-up of green house gases in the atmosphere from that source resulted in a complete melt-down of all that snow and ice in as little as 2,000 years.

Anyway, Laurentia beat feet and headed north, but Baltica remained in the south at least long enough to hang around Gondwanaland. After that, Baltica drifted north and approached Laurentia again. However, around 425 million years ago, Scotland-Greenland and Norway all collided together, forcing Baltica to look elsewhere for new continental buddies.

Just when you thought you’d found a friend. Poor Baltica.

* Now a piece of Central Russia

https://en.wikipedia.org/wiki/Baltica

https://www.google.com/search?q=baltic+states&oq=Baltic+states&aqs=chrome.0.0l6.4638j1j7&sourceid=chrome&ie=UTF-8

Cambrian Period

The Cambrian Period lasted from 541 to 485 million years ago. At the beginning of this time period, the small unicellulars that represented most life on Earth became more complex and multicellular. They also diversified quite rapidly, bringing forth the first representatives of all modern animal phyla. Indeed, there is strong evidence that all animals evolved from a single common ancestor.

Life prospered in the oceans, but the land is thought to have been relatively barren, with nothing more complex than a microbial soil crust or biofilm. A few molluscs may have emerged to browse on that biofilm, but the continents were probably dry and rocky. The global supercontinent Pannotia had just broken up during the early part of the period, and the new continents were mostly flanked by shallow seas, which were relatively warm. Polar ice was absent for much of this period.

Most land masses were clustered in the Southern Hemisphere during this period, but were drifting north. During the early portion of the Cambrian, the supercontinent of Gondwana went through some large, high-velocity rotational movements.

Trilobites (I wrote about them in an earlier post) were rampant during the Cambrian period. Possibly this was because without any sea ice, the sea level was high, which meant large areas of the continents were flooded in warm shallow seas, which is ideal for sea live. But the sea levels did fluctuate somewhat, suggesting there were ‘ice ages’, possibly meaning pulses of expansion and contraction of a south polar ice cap. Although the beginning of the period was cold, the average temperature during the Cambrian was 7° Celsius warmer than today.

Even so, trilobites were not the dominant species, as was once thought. It seemed they were, because they had hard external shells that were easy to fossilize, much easier than the thin chitinous shells of other arthropods, and so trilobite fossils were much easier to find by today’s paleontologists.

The Cambrian period is often referred to as ‘the Cambrian Explosion’, indicating a huge increase in the variety and diversity of life forms. But it seems (to me) that it might be better to think of it as ‘the Period of Great Changes’. At the start of the Cambrian, new creatures with new behaviors and lifestyles destroyed the biofilm that covered the sea floor, so all the creatures (from the previous time period) who depended on that biofilm died out.

Around 515 million years ago, the number of species dying out was larger than the number of new species coming into existence. 500 million years ago, the oceans saw a big drop in the oxygen content, and at the same time, the level of toxic hydrogen sulfide increased. Either of these events alone could produce extinctions, so imagine what happened when they came in together.

Where would hydrogen sulfide have come from? There are a few ways nature makes it, including anerobic digestion by certain biofilms in the absence of oxygen. I can’t rule that one out, but I’m somewhat more inclined to ‘blame’ volcanoes, which also produce it, probably in larger quantities and certainly can do it in oceans. Also, the heat given off by the volcano(es) would tend to drive oxygen out of the water. So, was there a series of huge volcano events 500 million years ago? I don’t know. It seems possible.

And there we have the Cambrian period in a nutshell. No fascinating dinosaurs to study, but the thought of a spinning Gondwana certainly has my attention.

https://en.wikipedia.org/wiki/Cambrian

https://en.wikipedia.org/wiki/Hydrogen_sulfide

Boreal Forest

If you want to talk about a forest that is larger than the Amazon jungle, then you will probably talk about the Taiga, the Boreal Forest or the snow forest. They are all one thing, with different names used in different parts of the world. Some say it is one huge forest, stretching from Iceland through the Scandinavian countries, Russia, Mongolia, Alaska and Canada. It is a coniferous forest consisting mostly of pipes, spruces and larches. It covers 6.6 million square miles or 11.5% of the Earth’s land area.

The boreal forest has a subarctic climate, with a very large temperature range between seasons. Summers last 1-3 months, always less than 4 months, and any given 24 hour period during the summer will average 50 °F or less. In Siberia, the average temperature of the coldest winter month is between 21 and -58 °F. The ground being frozen for much of the year, or even permanently frozen, can restrict the growth of deep roots, thereby favoring shallow-rooted trees like the Siberian larch.

Despite these harsh condition, the plants in the boreal forest have a lower threshold to trigger growth, and thus they ‘wake up’ a little earlier than one would expect. Even so, the soil tends to be poor in nutrients. Fallen leaves and moss tend to sit on the soil for a long time in the cold climate, so their organic components are very slow to be added to the soil. Also, acids from the evergreen needles leach the soil, making it even less ‘appetizing’ for anything but lichens and some mosses. On the other hand, diversity of soil organisms is high, comparable to a tropical rainforest.

It seems surprising to me that in a world that is frozen most of the time, fire is one of the most important factors that shape the composition and development of boreal forest. Some members of the boreal forest won’t release their seeds until the pods have been exposed to fire, and I get that, but how does something covered in snow most of the time suddenly burst into flames? Obviously, there is something about the process that I don’t understand.

Most boreal forest fires are either high-intensity crown fires or severe surface fires. These are large, often more than 10,000 hectares (a hectare is 100 acres) and sometimes more than 400,000 hectares. Different areas of the boreal forest burn at different lengths of time; drier areas might burn every 50 years, while wetter areas only burn every 200 to 300 years. And when an area burns, it could take decades, even a couple centuries to get back to ‘normal’. So all that carbon dioxide (a greenhouse gas) that is released into the air when those trees burn takes those same decades or centuries to be absorbed into the growing forest again.

This is particularly important now, when so much of the boreal forest is burning. Even Greenland - which doesn’t have any boreal forest, but does grow grasses and scrub brushes when enough ice melts to expose ground to seeds being blown around by winds - is on fire. Alaska and Canada are experiencing horrendous fires in their boreal forestland. In northern Siberia, one fire covered 7.9 million acres (over 3 million hectares), and that’s only one fire of 11 (or more) burning in Russia.

It’s been estimated that these fires dumped over 50 million tons of carbon into the atmosphere in June (2019), and they are still at it. 16 million adult trees burn in a day in Russia’s boreal forest fires. The Earth is not ready to absorb that much carbon. If we planted more trees - billions of them - it would help, but possibly not before the climate changes even more in response to that much carbon and carbon dioxide having been freed to begin with.

We really can’t sit around and wait any longer. We have to start facing this problem, and we have to do it NOW. The sky is falling, and doomsday is just around the corner.

https://www.dailykos.com/stories/2019/7/31/1875681/-Fire-at-the-top-of-the-world-Earth-s-largest-forest-is-burning-and-it-won-t-be-coming-back-soon

https://en.wikipedia.org/wiki/Taiga

What is This World Coming to? 7

And we are back to water. It seems only fitting, since the globe is mostly covered by it.

As I was looking over information on Central America, one of my hard-copy magazines - Popular Science - had an entire issue on water. Including an article on the sudden and sustained lack of water in Colombia in the northern part of South America.

The northern part of South America is also definitely in the tropics, because that area straddles the Equator, and the tropics is generally 30° north to 30° south of the equator. That’s latitude degrees, not temperature degrees.

Colombia is also quite mountainous, but that doesn’t mean their water supply is assured. The article spoke of one city sitting in the heights below a ski resort. Until recently, that resort could exist because of a glacier that sat atop the mountain. That glacier also was the source of the water used by the city.

Guess what. That glacier is gone now. Not just receding, like so many glaciers are, it is GONE.

No more skiing on that mountain, no more water for that city. Now the water officials load up what water is available into tank trucks and deliver it around the area. When the truck pulls up and stops, everybody runs for whatever they have that will hold water; pots, barrels, bottles and jars. They may go home and empty those items into their sinks or bathtub and run back to see if the truck is still there. If it is, they fill their pots, barrels and jars again.

They don’t know how long it will be before the truck arrives to deliver more water, so they have to be stingy with every drop. It is all they have for cooking and possibly a sponge bath. In the meantime, they listen for notices from the government as to when the water in their taps may be turned on for a limited time.

At one point, the author was with a woman who had stayed home from work that afternoon. The water was supposed to be turned on in the pipes for 3 hours, and she wanted to get some laundry done. But the water never came from her pipes that afternoon. No laundry got done.

Did all the women in the city stay home that afternoon, hoping to get some laundry done?

The article ended with a brief mention of another Colombian city on another mountain, also depending on the mountain-top glacier for its water supply. That glacier is visibly shrunken, smaller than anybody has ever seen it before.

Perhaps they’ll figure out another source for water. The article didn’t mention any attempts to look, to figure something out. Everybody - even the water officials - just kept saying, “The rains will come.”

What are we, ostriches? Refusing to acknowledge a problem will not make it magically go away!

This is a depressing subject, and not the type I would usually spend time on trying to spin into an entertaining novel. I suffer from chronic depression and just found an anti-depressant that actually works for me. I don’t know if I’m done researching this subject or not... my constant companion - depression - keeps telling me to stick my head in the sand and think of pretty things. But the story for the novel is beginning to take shape in my head. I think I’ll start thinking out scenes and where they would go, and speak of other things in this blog for a while. If I need to, I can still do more research.

So, next time, the subject will be... Oh, who knows? Whatever I find interesting between now and then.

What is This World Coming to? 3

So, what else is the Beaufort Gyre (which, you’ll remember, is north of Alaska) doing to The World As We Know It?

Well, it’s messing up the Arctic jet stream. Being from the midwest US, I’ve heard plenty of winter weather forecasts talking about the Arctic jet stream dipping below the Canadian border and bringing truly frigid blasts to the North American plains. Since I still have friends and family living in that region, I pay attention to the winter weather that happens there. Last year was particularly brutal, with that jet stream going much further south than I remember it doing in the past. It wasn’t just the northern states like the Dakotas, Michigan and maybe Nebraska hunkering down against Arctic-type temperatures, they were reaching into Kansas, Missouri, Illinois, Indiana...

How can that possibly mean the climate is warming? Let me remind you that climate and weather are not the same thing. Weather happens on a much smaller scale than climate. As for that Arctic jet stream coming south before returning north, that air gets (relatively) warmed up. Coming so far south, it gets a lot warmer than it normally does, so when it does go north again, it transfers the warmth it gathered to the area it goes; the arctic. More melting.

Earth’s polar ice caps serve a purpose; sunlight is reflected from their white surface, so they act as a ‘cooling’ agent for the entire globe. The more this ice melts and reveals darker-colored water and land, the less cooling is available for the entire planet. Get it? The more snow and ice melts, the more likely more snow and ice will melt. Until there is no more snow and ice to help keep Earth’s temperature moderated.

The really scary part is what happens to the land when all that snow and ice melts. If Greenland’s ice cap melts, the sea level would rise by 20 feet (6.1 m). At its current rate of melt, the Arctic Ocean could be completely ice free by 2040. That’s only 22 years! If all the ice of Antarctica melted, the seas would rise by 200 ft (61 m).

With a sea level rise of only 6 feet (1.8 m), most large cities would be flooded. So, where do you live? I currently live in the center of the Florida peninsula, which would still be here after 6 feet of sea level rise... but loooooong gone by the time all the ice melts. Maybe I should start cleaning out stuff I won’t be needing in my old age, so that it’ll be easier to move north, once that becomes necessary.

By then, New Orleans would be a bay reaching almost as far north as the Missouri boot. The Netherlands would be entirely below sea level, but much of it is now. Hope they have plans for building new, much taller dykes. Australia will be a doughnut, with land surrounding an inland sea. The Amazon rainforest will become the Amazon Sea, and Buenos Aires in Argentina will mean a huge bay. Those are the easy things to notice on the map.

At one time, I found an interactive map showing what parts of the world would be underwater, and the results would change depending on how much you chose to raise the sea level. It didn’t seem too alarming, but I think it only allowed you to raise the sea level by 9 meters.

Alas, I neglected to bookmark that page. When I went looking for it to link to this blog, I found lots and lots of pages with ‘interactive global sea level rise maps’. That means more and more scientists (and others) have been looking at this scenario seriously, and taking the possible sea level rise much higher. Much more ice than that covering Greenland has been and is and will melt, so 9 meters could just be a drop in the bucket.

Water isn’t the only thing that will change. Next time, I’ll examine something else from my research about climate change.

https://www.dailykos.com/stories/2018/9/5/1792312/-Warm-ocean-water-has-penetrated-deep-into-the-Arctic-interior-portending-year-round-loss-of-sea-ice

http://www.softschools.com/facts/environmental_science/polar_ice_caps_facts/2894/

What is This World Coming to 2?

Okay, we were talking about the sea and what climate change is doing to it. My examples last time were in Europe and the US, in the northern temperate zones. Now I want to consider all that ice and water in the extreme north and south, around the poles.

If you’ve been paying attention, you might remember news of huge chunks of Antarctic ice breaking away. I’m talking chunks bigger than some states. Antarctica is receiving warmer weather than it’s seen in millennia, or maybe even millions of years. Some coasts that certain types of penguin have called ‘home’ for countless generations are becoming inhospitable for them. They already live at the bottom of the world, where are they supposed to go from there?

The Arctic Ocean is not doing any better. There is no land under all that ice at the north pole, just water. You might think, ‘That’s okay, because it takes a lot of energy to warm water up.’ Yes, it does. And yet, that water under that thick sheet of ice has warmed up.*

If you look at a map or globe, you’ll see a bunch of islands above Canada. During Europe’s Age of Exploration, several well-provisioned ships made attempts to find a ‘Northwest Passage’ during the summers, trying to find a way to get around the Americas to do trade with the Orient. I don’t remember hearing of any of those excursions ever making it through, nor of any making it home again. At that time, I understand, whatever open channels of water that could be found among all those islands were unreliable and tended to close up and freeze a ship in place, even in summer. The last few years, so much of that ice has melted during the summer, that some cruise lines have offered cruises from one coast to the other, via the Canadian passage.

Something has happened to the Beaufort Gyre. That is a 60-mile-diameter pool of cold freshwater and sea ice located north of Alaska. It used to spin clockwise for 5-7 years, then slow down and start spinning in the opposite direction. This change in direction was caused by periodic cyclones that moved from the Northern Atlantic Ocean into the Arctic Ocean. But the North Atlantic has been warming up even faster than other parts of the world, and has failed to get the Beaufort Gyre to change direction in a dozen years or more.

So it’s just been sitting there, spinning and getting larger. And although it contains ‘cold’ water, that’s a matter of relativity. This spinning water contains twice as much heat now as it did 30 years ago. But it’s not sitting on top, like you’d think it would. It extends so deep, it is creeping under the Arctic ice sheet, which I understand can be a mile or more thick. Once it starts melting that ice sheet from below, well, how long before that ice sheet starts to break apart into gigantic icebergs, like the Antarctic ice has already started doing?

And what happens when all that ice breaks up and melts? Right, it raises sea level, which we discussed last time.

I had never heard of the Beaufort Gyre until a couple days ago, but I’m not done with it. From what I’ve been reading, whether it continues its current spin or starts going the other way, somebody’s in for a nasty time. Maybe it will come up next time.

* https://www.dailykos.com/stories/2018/9/5/1792312/-Warm-ocean-water-has-penetrated-deep-into-the-Arctic-interior-portending-year-round-loss-of-sea-ice

What is This World Coming to?

I firmly believe in climate change. In my mind, it is here, and it’s going to get bad.

But I’m not here to debate that with anyone. So, for the purpose of this series of blog entries, let’s say I’m trying to figure out what could happen (climate-wise) in the next 50 years, and how it will effect the people who have to live through it. Well, try to live through it.

The sea level will rise. There has been and still is a lot of water on the Earth that is not located in the seas. It’s not a liquid, it’s solid in the form of snow and ice. Glaciers, sea ice, and so on. This has all been melting at an increasing pace, and probably will continue until snow and ice become rare items.

You can already see the sea level rising, if you look; Miami FL has streets that are underwater during high tides. Miami Beach, located on a barrier island that barely qualifies as dry land, is quietly raising its streets, particularly the ones that run along the edges of the island.

After Hurricane Katrina hit New Orleans, there was much talk of how badly the shoreline was being eroded. If I remember right, there is an oil refinery or some such that was built on the shore. Now it is pretty much an island, and the road leading to it may or may not be passable during high tides. Those tides even reach 5 or 10 miles inland, making it hard to get in or out of small towns that dot that road. The road, I understand, has been raised in a lot of places, making it even harder to navigate in those small towns.

Parts of Amsterdam in The Netherlands are 18 feet below sea level. Much of The Netherlands consists of land ‘reclaimed’ from the sea and thus below sea level. They did this by building dikes, dams and canals to control where the water could go. This will be an ever increasing chore, as the sea rises.

So I find myself wondering, what happens when the sea rise reaches that critical point, whatever it is? Will The Netherlands continue building their dikes taller, until they loom and cast an ominous shadow over the land they are intended to protect? Is that possible? Does it make more sense to raise the land they are living on? Is that possible?

At what point do people simply give in to nature and move to higher ground? Do those who are displaced get any assistance from their government, or do they have to abandon the home they’ve had for who knows how long, take what they can to some other place, and try to start over again? I suspect the latter, because the former would probably bankrupt any government.

Even if Earth’s population doesn’t grow beyond what it is now, it’s possible the concentration of that population will increase, because there could be less land for us to live on.

Well, with the next entry, we’ll continue with the water theme. Yes, there is more about water to think about.

Martian Shelters Summation

Okay, so that was pretty much all I found for ideas about Martian shelters: tents of various shapes made of multiple layers of flexible plastic and insulation (probably foam), either buried in the sand or not; tunnels and rooms dug deep underground by robots; and a top-side shelter shaped like half a bagel with a layer of ice between the sheets of plastic.

I did see some reference to making a spun glass (fiber glass) insulation from sorting the Martian sand and melting a particular type of that sand. I’m not sure that would be available for the very first shelters, but maybe it would be a useful building material later on.

For that matter, rocks have been used to build human home for centuries, perhaps millennia. Sand could be combined with other materials to make a type of cement or even mortar. That assumes the colonists can find a supply of calcium silicate nearby, or some other binder to use. If not, they could use polymers, but that would need to be shipped to them from Earth, or they would have to make it on Mars, and I have no idea how complicated a process that might be.

One other idea, briefly mentioned, was to dig holes into a large boulder to create a small shelter, perhaps a type of emergency shelter. I kept thinking about today’s ‘tiny homes’ and thinking a sufficiently large boulder might make a nice small home for someone who really liked his/her privacy.

So, if you are going to be one of those first colonists sent to Mars, don’t expect a mansion. Of course, if you were expecting a mansion, you probably wouldn’t be one of those chosen to colonize Mars. Or anyplace else.

http://www.imagineeringezine.com/e-zine/mars-makeshelter.html

https://www.nasa.gov/feature/langley/a-new-home-on-mars-nasa-langley-s-icy-concept-for-living-on-the-red-planet

https://phys.org/news/2016-12-nasa-ice-house-mars.html

Martian Shelter 5

I was beginning to think we had run out of ideas, but it turns out I was wrong. So, how about an ‘ice home’? They’ve been used in the Arctic Circle for centuries, haven’t they? But, the ones proposed for Mars are a bit more complicated than igloos. They are, once again, inflatable, but... in the shape of a doughnut. The body of the doughnut would be where people would live and work.

The ‘skin’ of the doughnut would be a double-wall, flexible, of course. The interior wall would hold in the air and provide the space for people to occupy. The space between the 2 flexible skins would be filled with water and allowed to freeze. That outer wall and the ice under it would keep the radiation out, and protect the inner sections from any nasty weather Mars can produce.

Despite recent findings of water of Mars, it is not nearly as omnipresent as it is on Earth, so where does that water come from? No, it won’t be shipped from Earth. What they would ship from Earth is robots with the equipment to find, mine, and transport the water to the shelter area so it could be melted, pumped inside the walls and allowed to re-freeze.

Presumably, this store of water could serve a second purpose; that of being turned into fuel when it was time to leave. To me, this seems counter-productive. It assumes the people will be leaving, abandoning their colony to return to Earth. Even if they were ‘only’ there for a shift of a couple years, wouldn’t more people be expected to arrive to take over, like is done with the space station? On the other hand, keeping options open can be a very good idea.

Of course, with proper timing, those robots could be sent out to mine more water to replace what’s been turned into rocket fuel. You’d just need to make sure the equipment doesn’t get clogged with sand in the meantime.

The biggest drawback I see to this design is that it could take 400 days to fill and freeze the shell. So those robots had better know what they are doing in order to get it ready before humans start arriving.

https://www.nasa.gov/feature/langley/a-new-home-on-mars-nasa-langley-s-icy-concept-for-living-on-the-red-planet

Dione

I thought we’d talk about Dione today. That was before I found out there were 4 ‘Dione’s’ in Greek mythology and one in the Phoenician mythology of Sanchuniathon. Rather than try to sort through all those, I changed my mind and decided to discuss Dione, a moon of Saturn. (What or who is Sanchuniathon? I may have to come back to that one sometime.)

This moon was discovered by Giovanni Domenico Cassini in 1684. It is also sometimes called Saturn IV.

Dione’s orbit around Saturn is an ellipse, and at its closest approach, it is slightly closer to Saturn’s center than our own moon is to the Earth’s center. Because Saturn is a lot bigger than Earth, Dione races around it, taking 2.74 days to complete an orbit, as well as a Dione ‘day’. It never turns its face away from Saturn. It’s interesting that every time Dione completes one orbit, Enceladus (another Saturn moon) completes two. Each time they pass each other, the gravimetric tugging generates internal heat in both moons.

Also interesting is that Dione is one of a set of triplets. Two other moons of Saturn, Helene and Polydeuces, share the same orbit as Dione. They run around Saturn in single file, one 60° ahead of Dione, and the other 60° behind.

Who knew this kind of stuff could actually happen ‘naturally’? May I should have stuck with mythology after all.

It is believed that Dione is about 2/3 water in various forms, and the remainder is a dense core of silicate rock. The top of the ‘water’ is an ice crust, probably as thick as 99 kilometers ( 62 miles). The temperature at Dione’s surface is about -121°F, which would make the ice so hard, it would act like rock. Between the rock core and the ice crust is about 65 km ( 41 miles) of liquid ocean. The crust does have various features, such as chasms, ridges, long narrow depressions, craters and crater chains.

Dione is pretty well covered in craters, as large as 100 km (62 miles) across. However, most of the craters are on the opposite side as scientists expect them to be. The theory is that on something the size and mass of Dione, anything big enough to make a 35 km (22 mile) crater would be able to spin the moon about. There are enough large craters to indicate Dione did a lot of spinning in the past. So maybe she keeps her back to Saturn, trying to see the next spin-inducing attacker before it hits?

Oh, and let’s not forget the ice cliffs (formerly known as ‘wispy terrain’ when it was discovered by the Voyager space probe). At the time, they were called ‘wispy’ because whatever they were, they didn’t hide the countryside in their vicinity. But more recent photos by Cassini show that these ‘wispy’ lines were, in fact, ice cliffs, fractures created by chasms. We now know that some of them are several hundreds of meters tall.

In 2010, the Cassini probe detected oxygen ions around Dione, but there were so few of them, scientists prefer to call it an exosphere rather than a tenuous atmosphere.

en.wikipedia.org/wiki/Dione_(moon)

https://solarsystem.nasa.gov/planets/dione

Gone Fishing on Ganymede

In the past, fishing was a skill used to provide food for the table. Whether or not ancient man enjoyed the process, they needed to be good at it – or at hunting – in order to thrive. Today, fishing on a personal level has become a pleasurable activity for some. They don’t need to do it to put fish on the dinner table, but they find the experience rewarding. Some go so far as to try for ‘a big fish’ out in the middle of the ocean.

What do you suppose will happen when humans find their way to other planets?

Water has been found on our moon, Mars, Ceres, even Pluto, as well as various other places. On Ganymede, a moon of Jupiter, salty water is hidden under a thick (about 95 miles) crust of ice. There is probably more water on Ganymede than all of the Earth’s surface water combined. Scientists believe that ocean is 60 miles deep, about 10 times the deepest part of any Earth ocean.

I can envision future tours being organized to take die-hard fishers to Ganymede to drill a big hole in the exterior ice to facilitate fishing. I doubt if they’ll dangle a 100-mile-long fishing line into that hole – think how long it would take to reel it back in! So maybe their spacesuit for leaving the space boat would also be a diving suit, and they would ‘hunt’ for ‘fish’ with a spear gun.

Hmm. There’s problems with that vision, according to some of what I read. The Ganymede’s ocean is not only covered with ice, it also rests on ice, pressurized into a crystalized form. On other moons, the ocean bed is rock, which apparently keeps the water warmer, and provides various minerals as it is eroded by the salty ocean. The theory is that those warmer, rock-bedded oceans are far more likely to produce some kind of ‘life.’

Still, we keep getting surprised, the more we look around our neighborhood, don’t we? And science fiction writers like to take the science we know now and extrapolate possibilities we don’t – yet - have any proof for.

So, how about this? There’s a lot of different salts, besides table salt, which could be helping Ganymede’s ocean remain liquid. Nobody definitively stated the only salt in Ganymede’s ocean was NaCl (table salt), so these other salts could provide minerals for building ‘life’. I’m not sure the temperature of the ocean is that big a deal, but the salty ocean of Ganymede reacts to the magnetic field of Jupiter, and I’m thinking that reaction might produce some heat, although probably not much.

Sounds good to me. So good, I anticipate someone will make some money someday, selling signs that say, “Gone Fishing on Ganymede.”

http://www.space.com/28807-jupiter-moon-ganymede-salty-ocean.html

http://earthsky.org/space/underground-ocean-on-jupiters-largest-moon

http://www.planetary.org/blogs/emily-lakdawalla/2015/03121716-ganymede-ocean.html

Water, Water Everywhere

Earth has a lot of water; it covers roughly 75% of the planet’s surface, and it gets pretty deep - not quite 7 miles deep at one point. And for a long time, it seemed maybe Earth was the only planet in this solar system that had water.

If we sent people to explore or colonize any of the other planets, we would have to send water with them. The more people we sent, the more water they would need. Did Earth have enough? Would we completely drain the oceans?

Thankfully, we’ve learned better than that by now, since we are - tentatively - thinking about how best to colonize other planets. A brief recap:

1989 - Voyager studied Neptune’s magnetic field, leading to the conclusion that it has a subsurface ocean of water that is 4000°F (Hot!) and is under tremendous pressure.

1998 - Recent discoveries convince scientists that Callisto (a moon of Jupiter) might have a subsurface ocean.

2006 - Neptune has a large amount of water mixed in with its hydrogen/helium atmosphere. This is true also for Uranus, and since its density is only slightly higher than water, there is speculation that most of Uranus is water, in all its forms, with only a tiny rocky core.

2009 - Traces of water were found on the moon, then a ‘significant’ amount of water. Plans are being made for mining it, should we ever decide to colonize or set up a station there.

2010 - Water ice was found on two asteroids. Some surmised that there might be lots of water ice in the asteroid belt.

2011 - It was concluded that dark streaks on Martian slopes were made as salty water (ice) melts and slides down the slope. Water ice is also trapped in Mars’ polar caps, which can reach halfway to its equator during the winter. And a huge slab of underground water ice has been found in its northern hemisphere.

2014 - Ceres, the dwarf planet in the asteroid belt, was found to be spewing water vapor into space. It was speculated that Ceres might have more water than Earth does.

2014 - Gravity measurements suggest that a huge ocean sloshes around under the icy surface of Saturn’s moon Enceladus, which also spews water vapor from vents in its south pole. Titan, another Saturn moon, has an under-crust ocean saltier than Earth’s Dead Sea.

2014 - Scientists re-examined data from 1989, and now wonder if there is a subsurface ocean on Triton, Neptune’s largest moon - even if it does have the coldest surface in the solar system.

2015 - Using the Hubble Space Telescope, scientists found that Jupiter’s moon Ganymede has a huge salty ocean buried under a thick crust of ice. Laboratory experiments lead to the conclusion that there’s a subsurface salty ocean on Europa, another of Jupiter’s moons.

2015 - Water ice sheets were discovered on Pluto.

You get the idea - there’s plenty of water out there. It’s so fascinating a subject because life AS WE KNOW IT needs water. So when we find water - especially liquid water - in places you would think would be too cold, the next question is, Is there life there?

Let’s go find out.