Floaters – Onward to Mars etc

Floaters – Onward to Mars etc

In an earlier exchange I convinced myself that a dirigible on Mars was simply not practical. The issue is the low atmospheric density. It is much easier to design something to float in a dense medium. You and I can swim quite easily in water, but have difficulty flying, well, I do anyway.

The reason I am in favour of gas balloons is that once they are in flight they do not need energy to maintain them there. That makes them economical. This does not rule out hot-air (or other gas) balloons or gliders but they are issues for another day.

I don’t give up easily, and I thought I would investigate the possibility of using balloons on other bodies.

Bodies I investigated briefly and rejected:

Body:            Atmospheric Density:    Composition:

Mercury        “tenuous”                        -

Mars            0.02 kg/m3                        95% CO2

Ganymede    “micro pascals”                -

Europa           “tenuous”                        -

Jupiter            90% Hydrogen.             “Hydrogen and Helium in roughly solar proportions”

All the data is sourced from Wikipedia or other basic websites because I’m lazy.

Balloons are favoured by dense atmosphere composed of gases with a high molecular weight. Low gravity helps too.

Balloons are not practical on Mercury, Mars, Europa or Ganymede because of the low atmospheric density.

Jupiter is an interesting case. The atmosphere is so deep that there will be a wide range of density. The composition being mostly hydrogen means that something relying on pure “gas buoyancy” will not work (because you can’t get less dense that Hydrogen). On the other hand, the pressures are so high that the penalty for solids is less. Jupiter needs its own special, radical approach. Jupiter is not really rejected, but it needs a completely different approach.

Venus

On the other hand, gas balloons may have real potential on Venus!

Surface Temperature:    464 deg C

Pressure:                        92 Bar

Gravity:                          8.87 m/s2, 0.904 g

Atmospheric Density:    65 kg/m3

Composition:                  96.5%

If we assume ideal gas laws apply and the Venusian atmosphere is entirely CO2, then the density of a gas is simply going to in ratio to the molecular weight of the gas relative to CO2 (the other conditions, temperature and pressure remain constant).

This gives us the following:

Density of Atmosphere:                                65 kg/m3

Lift from 1m3 of vacuum:                            65 kg

Density of H2 at same conditions (2/44)      2.95 kg/m3

Lift from 1m3 of H2 at same conditions.      62 kg

Density of He at same conditions (4/44):      5.91 kg/m3

Lift from 1m3 of He at same conditions:       59.1 kg

There you are! If my sums are mostly right, that means that the high pressure and CO2 atmosphere means that on Venus 1 m3 of enclosed Hydrogen can lift 62 kg of load.

The Venusian atmosphere contains Sulphuric Acid. I would propose manufacturing hydrogen “in situ”. Possible routes are: bringing a reactive metal like lithium with you and reacting it with sulphuric acid, or breaking down the acid with energy. Suddenly making this practical becomes a materials-science problem.

Next Steps:

I prefer “back of a beer-mat” to “back of a fag packet” but that exercise convinces me that balloons are worth investigating for Venus. Next stage would be “back of an envelope”.

Do you know anything about aerodynamics and lift? (because I don’t). Are you aware of any equations I could use in a similar way to screen glider devices for different bodies?

I think gliders will be impractical on Mercury/Europa/Ganymede because of the low atmospheric density. I think they will probably either have to move far too fast or be vast. I’d like to do the sums for Mars (just to “show it won’t work”).

On the other hand, hot-“air” balloons and gliders (or “fish”) might be really interesting for Jupiter, but I’m still working out where to start. Any suggestions?

(Original 5th June 2021)

Drain problem in Cork City - Titan, Ceres and Dwarf planets

 Hi, Yes I though the Titan thing was good. As for the moons… well, it’s understandable. Our generation called Pluto a planet – the category of dwarf planets didn’t exist then, and all those moons are simply too much to remember. 

Titan is one of several places which look well worth investigating. In a perverse way, all these moons and some of the dwarf planets: Ceres and even Pluto, may make better targets for human occupation than planets. They are deep space but with a surface and no gravity well. https://en.wikipedia.org/wiki/Ceres_(dwarf_planet) Actually, the Solar System is looking more interesting than it has, but not in the ways or in the places we expected.

And… it hasn’t been a good week for me, and though I’m through it ok, I may be distracted suddenly for a while. 

On Wednesday evening, Noreen got a phone call from Margaret to say “there’s sewage in the yard” of our cottage down in Cork City. A photo was enough to confirm the issue and in the time it took to collect a few tools (overalls, gloves, drain rods…) and a change of clothing I was on my way (40 miles to Cork City). 

By 01:30 I had the mess cleared and had established that while the loo and shower-room drains were working satisfactorily, the gulley for the kitchen (which was the source of the effluent), was blocked. There had been things in that effluent which had not come direct from any kitchen and certainly not ours, including an almost complete sausage! No, I do not know what variety; it was like a length of garlic sausage with a reddish skin. The mess cleared up and it being possible to use the loo (but not the kitchen sink) I washed and went to bed.  

The following morning, Noreen (who fortunately is on vacation from school) was down at 09:00. While I started trying to clear the blockage, Noreen started on the internet and phone. In not so short order she went through: Irish Water, Cork City Council, 2 drains companies and even the Gardai (police, because we needed to get access to the house next door). Everybody was very helpful, but there were issues all along the way. Meanwhile, I bailed and “plunged” and groped.

By a miracle, “plunging”, persistence, groping in the darkness and with the use of chemicals, there was water movement by about 15:00 and by 16:00 I had the gulley draining in a satisfactory way. We had managed to resolve the immediate crisis for about EUR 30 on parking, EUR 20 on drain cleaner and whatever we spend on petrol. After I’d demonstrated the results, I washed up, we all shared some tea and a bun, and Noreen and Margaret went home, while I remained, to enjoy a TV dinner and a single can of strong cider. I went to bed early and I slept like a log.

The following day, I did a survey of my drains and the area. Compared to the previous night I felt amazingly relaxed. In the early afternoon I had a visit from someone from our preferred drains company. The bloke explained that we had two issues: 1) No rodding/jetting access and 2) No vent to relieve pressure from the sewer. The solution is going to have to be removing the loo pan and using the access into the sewer for inspection with an endoscope and then digging up the yard (guided by  the endoscope results), and then jetting and fitting a small inspection chamber. Really what is behind all this, is that I have a house which is over a hundred years old and the foul drainage has developed by a process of accretion.

I’ve fixed the immediate crisis, but now I have to take control of the project (because that is what it has become). Of course, the screws holding down the pan are badly rusted. I’m going to investigate removing the bowl but I’m reconciled to hiring a plumber and I know that the usual solution in these cases is to break the bowl – it’s easier and cheaper. If I get someone else to do the work, I will get them to fit easily removable screws and a service valve on the cistern at the same time (to save the need for draining the cold water tank in the future).

I’ve now got an excruciatingly large scale map (stolen from the Irish Gas website) of the relevant houses, and the results of my survey. Tomorrow evening I will investigate the loo pan and then we will move on from there. 

I may be busy for a few days…

Cheers, 

Tom

Trying to stay out of the brown. Onward to Mars, or Titan!   

(Originally posted 17th June 2021)

From: pink582 [mailto:pink582@btinternet.com] 

Sent: 10 June 2021 10:54

To: Tom Gillies

Subject: Re: Titan

Hello Tom,

thanks for doc about Titan, I may watch others in the series. When it comes to the moons I get a bit hazy....when there were only a handful of moons knowing their names seem to make sense but when you get 53 confirmed moons plus 29 other likely candidates....well I lost the plot.

two things did come out of the doc for me...1) the magnetic field of Saturn itself is strong enough to protect the atm of Titan from solar wind for 90% of the time...I also guess the solar wind is less dense out there.

2) very thick atm...if you want a fast trip to Saturn slowing down won't be so difficult...reference ballute idea in 2010 movie.....may be you could rig a past both through Saturn and Titan.

All the best

Jeff

------ Original Message ------

From: "Tom Gillies" <gillies.tom@googlemail.com>

To: "Jeff Pink" <pink582@btinternet.com>

Sent: Wednesday, 9 Jun, 2021 At 19:32

Subject: Titan 

I’m sure you will be interested in this, and I’m going to check some figures tomorrow

https://www.youtube.com/watch?v=qGy4uyHVUYA 

Regards,

Tom 

My response to a piece on "The Break-up of Russia"

 I watched the video about "The Break-up of Russia" (https://www.youtube.com/watch?v=jqYZqNpLQb8). Interesting. I agree with his conclusions, but for very different reasons. His reasoning seems to be that Russia will fall apart because of racial tensions. My reasoning is that Russia will fall apart for economic reasons and because of lack of cohesion.

Preable to my explanation:

As I say to people: Modern Russia IS NOT The Soviet Union WAS NOT The Russian Empire. There is obviously continuity between them but they are not (and will not become) the same. This may be one of Putin's major mistakes.

A metaphor: The fire brigade will point out that a fire needs three things: fuel, oxidant and a source of ignition. You need all three to have a fire.

Another metaphor: In a lot of things you get a balance between opposing forces. There can be an attractive force and a repulsive force. When one changes then the balance point changes.

I'm going to use Wikipedia as my sole source. Not entirely reliable but it's a starting point.

Introduction - The problem:

OK. During Soviet times there was a strong cohesive force which bound the SU together. Like it or not, many of the ordinary people _believed_ in the Communist Party. Soviet Communism was a religion. Many thought that though life was hard now, they were building a better tomorrow, if not for themselves, then for their children or grandchildren. They may have been deluded but they believed it. This belief helped bind the constituent republics and the various ethnic groups.

The Russian Empire was expanding imperial colonialism. As far as the colonists were concerned they were expanding into terra nullus, empty space. The russians expanded east until they encountered China or the Japanese coming the other way. Any cohesion was provided by racism and force. Those times are mostly gone.  

The ideological foundations of the SU have vanished. The binding force of Communism has gone. Putin has not replaced it with anything equivalent, and certainly not with anything which has the same power. There is no "Putinism". I don't think he has attempted to create a personality cult like Stalin; if he has, then he has failed. Though maybe even with the current mess, I still think he has a more powerful image than many Western leaders. The most he seems to have created (in this respect) is a particular kind of nationalism. And the thing is, that his "nationalism" is focused on Russia west of the Urals. It may have a binding effect there, but it has a different effect elsewhere.

Observation:

The more I learn about Russia and the ex-Soviet states the less I know. Until recently (last couple of years) I viewed Russia East of the Urals as "Siberia". That's mistaken, at least in part. Learning about Russia is like a weird lucky dip. You never know what you are going to find, and when you find it, you never know whether it is representative or not.

Russia East of the Urals

Russia is divided up in all sorts of different ways. This is one of those cases where "the more I learn the less I know". There are lots of different subdivisions (Oblasts, Krais, Okrugs, Riyons and nominally independent Republics), all within Russia. The arrangements are not strictly hierarchical either. There are all sorts of anomalies and exceptions. If you want an example of strangeness, look at "The Jewish Autonomous Okrug" (part of the Far Eastern Federal District)

The arrangement I am going to reference is "Federal Districts": 

Federal Districts are enormous - but notice how the Western ones are smaller.

The Far East 

Specifically I am going to look at the Far Eastern Federal District (FEFD): 

Some numbers:

• Area: 7 million km2
• Population: 8.4 million
• Population density: 1.2 /km2 = 3.1 people per square mile!

Compare that with the EU (not for political reasons, just size and diversity)

• Area: 4.2 million km2
• Population: 447 million
• Population density: 106 /km2

The population of the island of Ireland is 6.6 million, or if you prefer, the population of Greater London is 8.9 million.

The FEFD is 1.5 to twice the area of the EU. The EU has 100 times the population density of FEFD!

The population of the FEFD is comparable with the island of Ireland or Greater London!

Just like everywhere else, the population of the FEFD is concentrated in cities. I haven't found any useful figures for the how it is divided but I can imagine what effect that has on the population density of the hinterland.

Now look at the Ethnic composition of the population of the FEFD. All these "ethnicity" figures suffer from the problem that the numbers for the minorities get fragmented. In most cases I think it is appropriate to consider "Russians versus the rest" or maybe "Russians+Western SU Republics versus the rest". 

However you cut it, 78% of the FEFD identify as Russian!

My interpretation of this is that before the settlers came in the 16th to 19th Century this was a sparcely populated area with nomadic or semi-settled peoples. "Russians" (and other groups) colonised the FEFD. Often they had no choice. They overlaid the indigeneous populations. Compare this to British colonisation of USA/Canada/Australia/NZ. If this is the case, then the indigenous peoples will be mostly in the hinterland.

There may be ethnic tensions in parts of Russia, but ethnic independence is not going to drive a separatist movement in FEFD.

I don't know what the indigenous groups want, but my belief is that many of them would like access to the benefits of modern life, some want to migrate to the cities and others would just like to be left alone. They may be discontented but they will not revolt. 

The non-Russian, non-indigenous people probably feel ties towards their ancestral homes but they are in a (very small) minority. Again, they may be discontented but they will not revolt, and if they did, they would not be effective.

Now let's look at population change.

One specific component of the FEFD is Primorsky Krai (literally "Seaside" Krai).

Population: 2 million and is declining. But look at the map and compare the area of PK with that of FEFD.

The population is 92% ethnic Russian. Once again, _Ethnic_ independence is not going to drive separatism.

The human fertility rate is low between 1.5 and 1.7 for period between 2009 and 2016.

My extrapolation from these figures is that the population of PK will decline to between 1.5 and 1.7 million in 25 years (1 generation), say 2050 (I'm assuming that a fertility rate of 2 is necessary to maintain population).

Most of the Russian population of the Far East are descendants of people who arrived there in the past 150 years. Many were exiles, prisoners, were forcibly relocated or transferred to support Soviet mega-projects which are now no longer relevant. These are people who may feel "Russian" but have reasons to distrust the centre.

My perception is that there is dissatisfaction among the Russian population in the Far East and Siberia with how they are treated compared by "the centre" (the Moscow - St Petersburg axis). I have anecdotal evidence for this, but it is self-selecting and therefore biased.

Economy

The economy of the Far East and Siberia is based on extractive industries (mining and forestry) and heavy manufacturing. Infrastructure (roads and railways) is poor. Energy is provided largely by fossil fuels, especially coal. The Far East or maybe Primorsky Krai have huge natural resources but very sparse population.

The Triggering Spark:

I have seen reports that Putin is favouring using troops from Siberia and the Far East in Ukraine. That is to say - he is favouring the Moscow - St Petersburg region. This is one of several places where his policies are, shall we say, "confused". On the one hand he describes Ukrainians as "brothers" but then the actions on the ground could be designed to alienate ethnic Russians in Ukraine. If he is using troops from Siberia, and they are suffering badly, then that will create a groundswell of disaffection. Here is an example from a town close to Novosibirsk - https://en.wikipedia.org/wiki/74th_Separate_Guards_Motor_Rifle_Brigade#2022_invasion_of_Ukraine      

Conclusion:

My conclusion is that there is enough potential in the Soviet Far East to "drive it outwards" and not enough cohesive force to retain it and "pull it towards the centre (Moscow)". Moscow does not have the power to retain control of the Far East by force, but the population of the Far East retain a cultural and sentimental attachment to "Greater Russia".

The conflict in Ukraine may provide a further outward force driving opinion in Siberia and the Far East away from the centre.

China would benefit from closer relations with the Far East, but does not need to subdue it. Instead of a "revolution" or "withdrawal" of the Far East (in whatever form) from the Russian Federation, I would suggest that a "transfer of emphasis" is more likely. The Far East and Siberia may develop stronger economic ties with China (ignoring Moscow) while still claiming to be part of the political structure called the Russian Federation. You could argue that some of this was happening before the Ukraine crisis and that it will simply continue with China ignoring sanctions, possibly by using North Korea as a proxy.