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Old 07-13-2021, 08:05 PM   #11 (permalink)
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Not quite sure what you mean there. The title was shown in the previous post, and then it was just a continuation of that, broken up by Mindfulness's smiley. I'm not sure how it could have been hard to have followed the progression? It's basically one post, but split up because of the restriction on the amount of characters. Exactly like my posts about the Sun. And how the next ones will be, too. I can only fit so much in, and surely I don't need to re-title every separate post on the same subject as it follows?

"Previously, on Mercury..."
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Old 07-14-2021, 12:06 PM   #12 (permalink)
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I've used "...continued:" at times to help the reader along, but I'm a dork so there's also that.
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Old 07-14-2021, 03:24 PM   #13 (permalink)
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Quote:
Originally Posted by Plankton View Post
I've used "...continued:" at times to help the reader along, but I'm a dork so there's also that.

well I get what your saying Plonker..I say to be continued at times but also see what Trollybookends is saying also..flip of a coin..I can see two sides as an outsider.....Your trying to make it clearer and to Trolls it is clear...

dork your not Plonker yes....
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Old 07-29-2021, 01:45 PM   #14 (permalink)
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III: A Woman Scorned: Venus in Heat

In recent times - or at least, I’ve only heard it recently - our nearest neighbour has been referred to as “Earth’s evil twin”. This is because Venus exhibits many of the main characteristics of our home planet, and in some ways, is almost a future vision of it, or what Earth may become if we don’t get up off our arses and do something about global warming. You see, Venus is kind of the poster child, or indeed cautionary tale for climate change, having already undergone the effect of the release of greenhouse gases across the planet, thus making it uninhabitable, if it ever was so, and all but a vision of Hell, right on our own doorstep. Just shows how wildly inaccurate ancient astronomers were when they saw it in the heavens and decided to lavish upon it the name of the goddess of love.

Setting aside the surface similarities between our planet and Venus, there are marked differences and none of them are good, not for us and not for the planet. It is the hottest planet in the solar system, bar none (and this surprises me because before we began our little expedition I always assumed that to be Mercury) with temperatures reaching 464 degrees Centigrade, has an atmosphere almost entirely composed of carbon dioxide and features gentle, relaxing clouds of… sulphuric acid, lending a new meaning to the term acid rain! Atmospheric pressure on the surface is 92 times that of Earth’s at sea level, or to put it another way, if you want to know what a brisk stroll on Venus would be like, dive into the ocean and descend to about 900m (that’s 3,000 feet, and also the last time I’m calculating another measurement scale) and you’ll get the idea.

As I indicated a few paragraphs ago, Venus has fallen victim to the runaway greenhouse effect. And no, that doesn’t describe a thief legging it with your prize cucumbers. When the greenhouse gases on a planet’s surface (we’re all familiar with/fed up hearing about those) rise and block thermal radiation from leaving the planet, no water can form and any water vapour there is will be likely to escape through the stratosphere and out into space. Essentially, the planet can’t cool down, and so it becomes a burning desert of a planet, dry and arid and exceptionally hot. The main greenhouse gases are water vapour, carbon dioxide, methane, nitrous oxide and ozone. These gases are essential to life, but must be released into the air and dissipated. When this does not happen, as I say above, a runaway greenhouse effect results and you get a planet like Venus.

Venus is also the only other planet in the solar system not to have a single moon. In fact, in a weird coincidence, probably, the number of moons per planet increases as you move out into the solar system, with Mercury and Venus having none, Earth having one, Mars two and then of course the gas giants have them in the tens, Saturn having over eighty of them.

As if all the above though is not enough to classify Venus as a hell-planet, the atmosphere contains sulphur, and there may have been relatively recent volcanic activity on its surface. Let’s just say we won’t be landing there on our trip. I don’t think our insurance would cover it. What do you mean, you thought I was arranging it? Well now that's just... tell you what, say nothing to the others. I don't fancy taking an unscheduled space walk, do you? Anyway, where was I? Oh yes. No need to worry about insurance, everything is fine. So Venus has no moons. Right. Nevertheless, it is the brightest object in the sky, and you’ve no doubt seen it, even if you haven’t realised or cared what it was, on a clear night.

Most of the surface of the planet is covered by smooth volcanic plains, the rest composed of two highland plains, one of which, Ishtar Terra, boasts an eleven-kilometre high mountain (that’s like eleven Everests stacked one on top of the other) and unlike Mercury the surface of Venus features few craters, and is relatively smooth. This means the planet is quite young, a mere babe in arms actually, no more than 600 millions years old (ahhh!) and possibly even as young as 300. Coochy-coo! Ahem. There are features called farra, which are mostly flat, pancake-like depressions, arachnoids, which are not, as you might fear, robot killer spiders that patrol the surface, but rather radial or concentric fractures which look like spiders’ webs, coronae, circular rings of fractures which are often surrounded by a depression, and have nothing to do with the sun, and novae, radial, starlike fractures. All of these stem from volcanic activity.

Like its little brother, Mercury, the possibility for life seems to exist on Venus, although the detection of phosphine - a gas which scientists believed was impossible to create in Venus’s chemical atmosphere, and could only have come from living organisms - in the clouds above the planet have actually given rise to speculation that life currently exists there, albeit, again, no life we would recognise. No Venusian war wizards, for instance, or nubile princesses living in sky cities. Sorry, Mr. Burroughs! Mind you, Carl Sagan had been saying this since the sixties: While the surface conditions of Venus make the hypothesis of life there implausible, the clouds of Venus are a different story altogether. As was pointed out some years ago, water, carbon dioxide and sunlight—the prerequisites for photosynthesis—are plentiful in the vicinity of the clouds

(“Life in the Clouds of Venus?” - Carl Sagan and Harold Morowitz, Nature Magazine, September 16 1967)


Still, this hypothesis seems to have been discounted after October 2020, when a re-examination of the clouds seemed to show no signs of phosphine, and the belief is that - without going into scientific terms which I neither understand nor care about - somebody fucked up and detected something that was not there. Well, I suppose at least the Venusians won’t be coming over here, taking our jobs, stealing our women...

The winds on Venus are very sluggish, but powerful nonetheless, mostly due to the very high density of the planet’s atmosphere, and the dispersal by the winds of dust and small stones across the surface. It’s pretty much the same wherever you go on the planet, or when, as neither seasonal changes nor geographic location varies across Venus, its axial tilt, while still a lot more pronounced than that of Mercury (but then, so is that of any other planet in the system) is a mere three percent and therefore doesn’t permit much in the way of change. In fact, if you want to cool down you’re best scaling that 11 km-high mountain, Maxwell Montes, where you’ll be able to bask in the refreshing temperature of a nice cooling 350 degrees C. Lovely! Yeah, that’s as cool as it gets on this planet. Oh, and that stuff that looks like snow on the peaks? Take my word for it, it’s not.

Despite the slow winds on the surface, if you were to somehow attempt to fly on Venus you would find it a whole different matter, as the winds up in the clouds rush around at about 300 kph every four or five days. That’s way faster and stronger than our Storm Force 10 winds on Earth, or the kind of winds that accompany the likes of hurricanes, which rarely reach over 120 kph. Venus has no seasons, no real weather, certainly no rain, ice or snow, though there is some speculation that it gets lightning storms. This however has not been proven, and there is plenty of doubt as to whether this could be possible in the dense atmosphere of the planet.
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Old 08-12-2021, 05:15 PM   #15 (permalink)
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Venus differs from all other planets in the solar system by rotating clockwise, and very slowly, making its days longer than its years. A Venusian day is 243 Earth days while a Venusian year is only 225. Because of its atypical rotation, were it possible for it to be seen through the thick clouds of sulphur, the sun would be seen to rise in the west and set in the east on Venus. Although the planet has no moons, it’s theorised it may have had once, but either the lack of solar tides destabilised it/them and made it/them crash into Venus, or a large impact event, thought to have taken place millions of years after the planet had formed, may have resulted in the same outcome. Venus does however have small satellite asteroids, called trojans, which orbit it. Sure they do Trojan work, they do! Sorry.

Transits of Venus are not tough rugged white vans that haul cargo between here and there, but times at which the planet passes between the sun and Earth, and therefore becomes visible against the surface of the sun as a black spot. These transits usually take hours to complete, are often visible to the naked eye, and occur very infrequently, normally with about a century between one and the next. They occur in pairs, usually eight years apart. They can be likened to eclipses, and in addition to providing a pretty spectacular sight, help scientists to work out all sorts of things, including, recently, the existence of exo-planets (planets outside of our solar system) and prior to that, the size of the astronomical unit (AU).

As one of the brightest objects in the sky, Venus can be, and has been, observed in daylight. I believe I may have seen it myself. The ancient Greeks believed it was two planets, as Venus vanishes behind the sun for several days and then reappears: they called it Phosporos, the bringer of light, when they could see it in the morning, and Hesperus, the star of the evening, when they saw it at night. Later these two words became Lucifer, light bearer, the morning star.

Venus was in fact the first planet humans ever visited, albeit not personally, and a glut of space probes headed there during the late twentieth century. However, because it is impossible to land there, and the planet couldn’t be colonised or terraformed or mined, interest in its observation and exploration has waned in the twenty-first, as we focus on Mars and, um, Pluto? However before interest was lost, there was some discussion about terraforming the planet. Some of these ideas have to be read to be believed.


Terraforming Venus: Truth is weirder (and more hilarious) than fiction!

Can we terraform Venus?

Yes we can!
Maybe...


Note: if anyone reading this is affiliated with NASA or involved in this sort of research, I'm not laughing at your ideas. Well yes I am, but then who knows what's possible? They said men would never fly. They said the Earth was flat. They said the moon was not made of green... what? Really? You're sure about that, now, are you? Excuse me, I have to call my broker right away!

Making Venus habitable hinges on three important factors. First, lowering the temperature to at least a tolerable level that would not reduce any colonists to sticky slop on the ground. Second, filter the atmosphere: that carbon dioxide might be great for plants (not that there are any on Venus, as there is no water and they’d just burn up anyway) but it ain’t good for we humans, and Venus’s atmosphere is chock-full of it. Finally, as Venus has no oxygen, we’d have to get some in there. Call in the Oxygen Board! What do you mean, you’re cutting us off as we didn’t pay our bill?

Here's a fellow nerd to explain some of how it might be done...

And here's another, with cool animations...


Mirror, mirror, in the sky...

Look, I’ve read some crazy things about the proposed exploration and colonisation of Venus, among them the idea of people floating around in balloons and sky cities (I ain’t kidding, you’ll see!) but glancing down I see the words “space mirror” and, well, it’s like candy to me. I got to go see what this is about.

Oh, man! That is like something out of Futurama. Except, it’s real. Apparently. The idea is to combat the “two-month Venusian night” by having a 1,700 metre mirror on a satellite orbiting the planet, in order to dispel the darkness and light up the planet with the “luminosity of 10-20 moons.” Oh, dear. What else is there? This is comical.

Because it’s there. Well, not yet it’s not, but it could be.

Okay, okay. Also proposed was a 50km-high mountain that would be so high that the temperatures at its summit would be tolerable for human habitation, and everyone would live on this mountain. Oh dear lord. If you go for a walk, John, make sure you don’t stray too close to the edge there. It’s a long way downnnnnnnnnnnnnnnnnnnnnnnn….!


Ice, Ice baby: once in a blue moon


Oh merciful heavens, my sides! Look, this may all be accepted as sound scientific practice, but I just can’t help laughing at some of these suggestions. How about crashing Venus into one of the ice moons on the outer edges of the solar system, where there is a plentiful supply of water in the ice there? Or is i the other way around? Yeah, probably. That should solve the water problem on the planet! How in the name of Captain Jean-Luc Picard are you supposed to do that? I worry about people like the guy who had this idea, one Paul Birch, especially when he quips “In theory, you could flick a pebble into the asteroid belt and send Mars crashing into the sun.” What? I mean, what? No, like, I really mean, what??

You’re fired, sun!

Futurists are weird people, but hey, this is a weird section, and to be honest, while supposedly all of this is doable, at least theoretically, it’s rare science can be laughed at, so I’m taking the opportunity where I can. I’m not saying these ideas are crazy, but, well, you decide. The latest one here is for a process called starlifting to occur. Apparently, this involves siphoning off part of the Sun’s hydrogen, via - wait for it - an ionised particle beam which he’s decided to call a hydro cannon - and aiming it at Venus. This is supposed to do two things: thin the dense atmosphere and introduce hydrogen into the atmosphere, which will then react with the carbon dioxide and create h20. Okay. And they let this guy out on his own? No, seriously, I’m asking.

Taking the air - literally!

Even our buddy Carl Sagan has been at it. First he proposed, early in the sixties, introducing genetically engineered biological life forms into Venus’s atmosphere which would convert the carbon dioxide into carbon, but that idea was shot down. He admitted the plan was predicated on insufficient data, as the Enterprise computer was often fond of saying, in his book Pale Blue Dot, published thirty years later:

"Here's the fatal flaw: In 1961, I thought the atmospheric pressure at the surface of Venus was a few bars ... We now know it to be 90 bars, so if the scheme worked, the result would be a surface buried in hundreds of meters of fine graphite, and an atmosphere made of 65 bars of almost pure molecular oxygen. Whether we would first implode under the atmospheric pressure or spontaneously burst into flames in all that oxygen is open to question. However, long before so much oxygen could build up, the graphite would spontaneously burn back into CO2, short-circuiting the process."

Yeah, Carl: I don’t think we’re too bothered about whether we implode or burst into flames. We’d prefer to do neither, thanks.

Then he had the idea to smash asteroids into the planet so as to shake the atmosphere off the planet. I guess that wouldn’t work with most planets, as they have a strong enough magnetic field to retain their atmosphere, but Venus’s is really really weak. Cartoon-like though, it was realised that if they didn’t hit the planet hard enough and with enough asteroids the atmosphere might just hang around in space and then drift back down onto the planet. What a waste! The planet could even regenerate its lost atmosphere through a process called outgassing, apparently.

And hey: let’s not forget that a mere few tens of millions of kilometres away is a planet we all know and love, and personally, the idea of bouncing bloody great rocks off our nearest neighbour in an attempt to get it to do a Taylor Swift and shake it off worries me. What if one bounced our direction? D’oh! We’re talking about rocks at least 700 km across - that’s like twice the size of Vienna - and not just one. They reckon it would take two thousand impacts! With that many asteroids of that size, can you really expect one or two not to go off-course and head our way? “Hey, it didn’t work, but look on the bright side: at least we flattened Jersey!”

I, uh, I don’t think his elevator goes all the way to the top floor, if you know what I mean!

Oh yeah, they’re real, at least hypothetically. Space elevators. Sounds like something out of science fiction, but here’s the deal. A cable is anchored to the planet and out into space, where, um, competing gravitational forces apparently hold it up, and then vehicles can travel along the cable, up and out of the atmosphere and into space. Are you shitting me? Would any of us even consider such a mode of transportation? You know what happens when one of those cable cars in Switzerland goes down, right? Well as it happens we would need this magic cable to be made out of a super-strong material which does not yet exist, so don’t get your space-climbing boots on just yet! And as a solution for Venus, it’s out even if we had the materials, due to the thickness of the atmosphere and the height of the planet’s geostationary orbit. Uh-huh.

Then there’s the space fountain. I am being serious! Listen, a tower created by a space fountain might work, it says here. Pellets are shot upwards in a stream to a ground station abo - what? I have no idea what kind of pellets, though I doubt they’re the type you load your BB gun with. Don’t ask stupid questions while I’m outlining a stupid idea. Well it sounds stupid, but what do I know? Anyway where was I? Oh yeah. The stream of pellets is directed downwards from the station at the top (I don’t know how! Didn’t I ask you to stop asking questions? Here, have some jelly babies) and, so it says, “the necessary force for this deflection supports the structure at the top and the payloads going up”. Sure it does. Will. Would. Might. Oh look! The downside is apparently that if the containment fails and the stream breaks you’re SOL. All I can say is I wouldn’t want to be using one of these space fountains during space rush hour. Or, you know, ever. If I want to leave this planet, I’ll do it the old-fashioned way, in a rocket ship. Or by getting high. Or reading a book.

The future’s so bright I gotta wear shades

Solar shades sound like something a planet might wear to look cool, but in fact they are proposed actual parasols in space that would, I guess, presumably be mounted on a satellite? I don’t know, I’m in the dark here (pun!) but the idea is pretty simple at its core (other, less immediately obvious pun), in that the shade thrown on Venus by these parasols (presumably again there’d have to be a lot of them, or they’d have to be really big) would reduce the heat and therefore cool down the planet. Placed in the correct position (no I am not going to use the proper scientific designation, that’s not what we’re about here) it could also deflect the radiation from the sun and block the solar wind.

And now it gets funny.

The proposed size of this theoretical shade is, wait for it, four times the size of Venus itself. But that’s not the best part, oh no. If left to itself without supervision, the thing is expected to act as a solar sail, and just bugger off on its merry way, leaving Venus unshaded and NASA seriously out of pocket with no result to show for all that expenditure. So to prevent this rather embarrassing but certainly amusing accident from occurring, the idea is to either make it an artificial, controlled satellite, or staitite (I guess a portmanteau of static and satellite?) or - and here we’re back to mirrors again - install huge mirrors at the poles which could reflect the light back at the rear of the solar panel and balance them, keeping them in orbit.

Float, float on…

Ah, we’re finally dealing with those floating cities which occasioned so much mirth a while back. Yes, it’s true. If we can’t live at the top of miles-high mountains we can just drift about like those guys in Gulliver’s Travels, or like the drifting never-ending party in The Hitch-Hiker’s Guide to the Galaxy. Or even like those, well, floating cities in Star Trek. Here’s the supposed hard science, though for my money there’s a fiction missing at the end, and possibly even a humorous before it.

Human-breathable air is a lifting gas (as those of you who read my Aviation journal, particularly the section on the history of ballooning, will know, early balloons were filled with simple oxygen before others got around to using hydrogen and then helium) and in Venus’s dense carbon dioxide-rich air would provide sixty percent of the lifting power of helium back home. Venus is a beautiful planet - until you hit the tops of the clouds on the way down. It’s just the surface, the atmosphere, the clouds, all that area, that’s shitty. If we could live - to quote the title of again my aviation journal - above the clouds, we’d be laughing. Well, I’d be laughing that’s for sure.

So, cities drifting along lazily at an altitude of about fifty kilometres above the ground, inhabitants enjoying both the Earthlike atmosphere and temperatures ranging from 0 to 50 C would only have to worry about those pesky winds I mentioned, which blow every four or five days around the planet at a speed of up to 340 kph. Right. For some reason, the eggheads don’t seem to think this is a problem. I personally wonder what it would be like to look out of your apartment window into the clear blue sky and say “wind’s not bad today! Only 300 kph!” as your best friend goes sailing by, madly hanging on to his smaller apartment. Also, how are you supposed to eat while up there? Where is anything going to grow? What about cattle and livestock? Would they adjust to being permanently in the air?

Look, I’m just going to copy/paste these paragraphs from Wiki. Note the first is headed “advantages”. (Bolded text is added by me).

Advantages

Because there is not a significant pressure difference between the inside and the outside of the breathable-air balloon, any rips or tears would cause gases to diffuse at normal atmospheric mixing rates rather than an explosive decompression, giving time to repair any such damages.[11] In addition, humans would not require pressurized suits when outside, merely air to breathe, protection from the acidic rain and on some occasions low level protection against heat. Alternatively, two-part domes could contain a lifting gas like hydrogen or helium (extractable from the atmosphere) to allow a higher mass density.[14] Therefore, putting on or taking off suits for working outside would be easier. Working outside the vehicle in non-pressurized suits would also be easier.[15]

Remaining problems

Structural and industrial materials would be hard to retrieve from the surface and expensive to bring from Earth/asteroids. The sulfuric acid itself poses a further challenge in that the colony would need to be constructed of or coated in materials resistant to corrosion by the acid, such as PTFE (a compound consisting wholly of carbon and fluorine).

Yeah. I don’t see not having to wear a spacesuit to go to the shops or football practice or the office necessarily an advantage, guy? And to categorise the fact that “any rips or tears” won’t explode the balloon? Um, isn’t this damning with faint praise? Shouldn’t they be saying there is no possibility of rips or tears? I mean, correct me if I’m wrong, but if I’m living in a city carried around on a potentially hostile, even deadly planet by fucking balloons, I really don’t want to hear the words rip, tear or christfuck explosive decompression! And under “Remaining problems” (as if those weren’t enough) we have two words which, again, nobody floating around in a balloon wants to consider: sulphuric acid. Sulphuric acid that falls from the clouds in showers of rain. All in all, I’d take my chances on the ground, thanks.

So, who’s first to sign up for the wonderful Floating Balloon City on Venus? Anyone? Hello? Hello?

By the way, as an aside, you have to give it to NASA. Setting up a study to examine the feasibility of an atmospheric crewed mission to Venus, they called it the High Altitude Venus Operational Concept. That’s right: HAVOC. Is there something wrong with these people, or have they just all got a twisted and warped sense of humour? Havoc? Why not call it Operation Doom while they’re at it?
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Old 08-18-2021, 10:18 AM   #16 (permalink)
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Back down to Earth, or I should say, Venus: it’s time for those specs again!

Distance from the Sun: 107,000,000 km
Distance from Earth: 233,000,000 km
Mass: 0.815 Earths
Volume: 0.857 Earths
Surface Gravity: 0.9g
Pressure: 92 Atmospheres (ATM)
Satellites: None
Axial tilt: 2.64 degrees
Temperature: 464 degrees C
Length of day: 244 Earth days
Length of year: 227 Earth days
Atmosphere: almost entirely Carbon Dioxide

Probes sent

It should be noted for posterity and accuracy that in 1961 Russia - then the Soviet Union, or USSR - made two unsuccessful attempts to send probes to Venus, one of which exploded on the launch pad, the other of which did make its destination but had a catastrophic failure and was unable to send back any data. The US also tried with Mariner 1 in 1962, but this failed to achieve orbit and was destroyed, while the Russians gave it one more go literally two days before the launch of the second US attempt (which ended up being successful), but again the orbiter malfunctioned and this third attempt was also a failure, allowing the hated Americans to get there first. Maybe they saw it as revenge for Sputnik.

Russia would try a total of eight more times between 1962 and 1967, and rather interestingly finally succeed in launching its ninth probe two days before the next American one (there had been no further missions by the USA in the interim, possibly due to Vietnam?) and arriving in Venusian orbit literally one day ahead of it.

Note also that due to the fact that the Cold War was freezing both superpowers, and trust was at a minimum between them, information about the Soviet space programme was seriously and jealously guarded, and so the details we have here on their probes to Venus may be a little sketchy, but they’re all I could find.

Mariner 2

Launched: August 1962
Reached Destination: December 1962
Type: Flyby
Nationality: American
Results: Measured the temperature of Venus, confirmed no real variance across the surface of the planet, also studied the solar wind, thickness of Venus’s atmosphere, clouds. Mass estimated, confirmation of its rotating clockwise and its speed, and updated information on the astronomical unit size.
Photographs taken: None (No camera on board)
Mission ended: 1963
Termination of probe: n/a; still in heliocentric orbit (orbit around the Sun)

Venera 4

Launched: June 12 1967
Reached Destination: October 18 1967
Type: Atmospheric Entry
Nationality: Soviet (Russian)
Results: Analysis (for the first time) of Venus’s atmosphere while within that atmosphere, measurements of the weakness of the magnetic field, confirmation (at the time - almost more educated speculation really) of the absence of water.
Photographs Taken: None
Mission Ended: October 18 1967
Termination of Probe: Crashed on surface

Mariner 5

Launched: June 14 1967
Reached Destination: October 19 1967
Type: Flyby
Nationality: American
Results: Analysis of the atmosphere, temperature, magnetic field
Photographs Taken: None
Mission Ended: October 14 1968 (technically, December 4 1967, after which contact was lost but re-established briefly in 1968)
Termination of Probe: Remains in heliocentric orbit

Venera 5

Launched: January 5 1969
Reached Destination: May 16 1969
Type: Lander
Nationality: Soviet (Russian)
Results: Confirmed temperature, pressure and atmospheric readings sent back by Venera 4; was the first man-made probe to land on Venus.
Photographs Taken: None
Mission Ended: May 16 1969
Termination of Probe: Crushed on the surface of Venus less than an hour after landing, due to the immense atmospheric pressure.

Venera 6

Launched: January 10 1969
Reached Destination: May 17 1969
Type: Atmospheric
Nationality: Soviet (Russian)
Results: Sent back data on samples taken from the atmosphere
Photographs Taken: None
Mission Ended: May 17 1969
Termination of Probe: Crushed on the surface, like its predecessor

Venera 7

Launched: August 17 1970
Reached Destination: December 15 1970
Type: Lander
Nationality: Soviet (Russian)
Results: Further information on the composition of Venus’s atmosphere, surface temperature and for the first time, weak but definite signals confirming the planet has a solid surface and that there is (or was thought at the time) no water there. On landing, the vehicle seems to have fallen on its side, which scrambled the data it was sending back. This is thought to have been due to initial partial, and then complete failure of its descent parachute, leading to a harder landing than anticipated. Nevertheless, Venera 7 attained the distinction of being the first man-made probe to land safely on another planet.
Photographs Taken: None
Mission Ended: December 15 1970
Termination of Probe: Probably shut down on the surface and likely crushed flat.

Venera 8

Launched: March 27 1972
Reached Destination: July 22 1972
Type: Lander
Nationality: Soviet (Russian)
Results: Confirmed the temperature and pressure readings of its predecessor, noted that the cloud cover did not extend far down to the surface, and from beneath the clouds the atmosphere was relatively clear. Also determined that the light on the surface would be conducive to the taking of photographs. Venera 8 became the first ever man-made probe to land successfully on another planet.
Photographs Taken: None
Mission Ended: July 22 1972
Termination of Probe: Crushed on the surface, again.

Mariner 10

Launched: November 3 1973
Reached Destination: February 4 1974 (before moving on to Mercury, its primary target)
Type: Flyby
Nationality: American
Results: Mariner 10, though really intended as a probe to study Mercury, as we have seen in the article on that planet, became the first probe to send actual photographs back, though they were of course only from a flyby and so not very detailed. It was however able to photograph for the first time the clouds that cover Venus, and other instruments analysed the composition both of the clouds and the atmosphere itself.
Photographs Taken: 4,165
Mission Ended: February 13 1974 (for the Venus part of the mission - March 24 1975 for the full mission)
Termination of Probe: In heliocentric orbit

Venera 9

Launched: June 8 1975
Reached Destination: October 20 1975
Type: Orbiter/Lander
Nationality: Soviet (Russian)
Results: Took photographs for the first time of the surface of Venus, confirmed the light was about the same as Earth but without any direct sunshine due to the thick clouds above. Measured the atmosphere, pressure, the composition of the clouds and the surface temperature.
Photographs Taken: Yes, but number unknown (those secretive Russians!)
Mission Ended: October 22 1975 (Lander) / March 22 1976 (Orbiter)
Termination of Probe: Unknown

Venera 10

Note: tensions were so high during the Cold War, and each of the superpowers (USA and USSR) trusted the other so little that when this probe was launched, the Soviet Union claimed it was only an orbiter, though a lander was also attached. Western sources assumed they were lying, and as it turned out, they were.

Launched: June 14 1975
Reached Destination: October 26 1975
Type: Orbiter/Lander
Nationality: Soviet (Russian)
Results: Measured surface windspeed, atmosphere, temperature and took more photographs of the surface of Venus.
Photographs Taken: Yes, but number unknown
Mission Ended: Believed to be June 1976
Termination of Probe: Unknown
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Old 08-18-2021, 10:25 AM   #17 (permalink)
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Terraforming Venus would be nuts
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Old 08-18-2021, 10:34 AM   #18 (permalink)
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Venera 11

Launched: September 9 1978
Reached Destination: December 25 1978
Type: Flyby/Lander
Nationality: Soviet (Russian)
Results: Catalogued gamma-ray bursts for the first time; studied the temperature, soil and atmospheric composition (soil analyser failed however), detected lightning on Venus for the first time.
Photographs Taken: Unknown
Mission Ended: February 1980
Termination of Probe: In heliocentric orbit

Venera 12

Launched: September 14 1978
Reached Destination: December 21 1978
Type: Flyby/Lander
Nationality: Soviet (Russian)
Results: Observed more gamma-ray bursts, analysed composition of the atmosphere, thermal balance and the nature of the clouds.
Photographs Taken: None; both cameras failed to operate on landing.
Mission Ended: April 1980
Termination of Probe: In heliocentric orbit

Pioneer Venus 1

Launched: May 20 1978
Reached Destination: December 4 1978
Type: Orbiter
Nationality: American
Results: Mapped the surface with radar, investigated the distribution of the clouds, the composition of the atmosphere, infra-red emissions, measured the magnetic field and the solar wind, monitored gamma-ray bursts. Also observed Halley’s Comet from orbit around Venus.
Photographs Taken: None
Mission Ended: October 22 1992
Termination of Probe: Burned up in Venus’s atmosphere after its orbit decayed

Pioneer Venus 2

Note: this was the first hybrid or multi-probe, containing five separate components - four probes and the spacecraft that carried them. The probes were dropped into Venus’s atmosphere without parachutes, recording as they descended. They were not intended nor designed to survive the impact on the surface, though one did.

Launched: August 8 1978
Reached Destination: December 9 1978
Type: Atmospheric
Nationality: American
Results: Determined the nature of the solar wind, the development of the atmosphere, measured distribution of infra-red radiation
Photographs Taken: None
Mission Ended: December 9 1978
Termination of Probe: Destroyed on impact (3 probes); fourth one presumably crushed on the surface

Venera 13

Launched: October 31 1981
Reached Destination: March 1 1982
Type: Flyby/Lander
Nationality: Soviet (Russian)
Results: Took soil samples and analysed them; first ever recordings from another planet as the probe was fitted with microphones.
Photographs Taken: Yes, but number unknown. They appear to have been possibly the first ones in colour, too.
Mission Ended: March 1 1982
Termination of Probe: Again, unsure but presumably crushed by the pressures on Venus’s surface.

Here’s a hilarious little story. Seems some of the Russian scientists got really excited when the cameras from the lander picked up what they described as “a disc, a black flap and a scorpion (!) which emerge, fluctuate and disappear” on the photographs. Engineers later shook their heads wryly and said, “they’re just the discarded lens caps from the cameras blowing in the Venusian wind, comrade!”

Venera 14

Launched: November 4 1981
Reached Destination: March 5 1982
Type: Flyby/Lander
Nationality: Soviet (Russian)
Results: Pretty much the same as Venera 13 (it landed only 4 days after it, and was more or less identical).
Photographs Taken: Yes, but number unknown
Mission Ended: March 16 1983 (orbiter)
Termination of Probe: Crushed on the planet

Another funny story (and you don’t expect many of them to come out of the cold, hardline, humourless regime of the Soviet Union in the early 1980s): when the lander tried to measure the compressibility of the soil, it accidentally instead focussed on the discarded lens caps from the cameras (oh, those lens caps again!) which had popped off and fell beside its measuring arm. Oops!

Venera 15

Launched: June 2 1983
Reached Destination: October 10 1983
Type: Orbiter
Nationality: Soviet (Russian)
Results: Nothing exciting; a few experiments carried out with radar and imaging.
Photographs Taken: Unknown
Mission Ended: January 5 1985
Termination of Probe: Unknown


Venera 16

Launched: June 7 1983
Reached Destination: October 11 1983
Type: Orbiter
Nationality: Soviet (Russian)
Results: Identical to Venera 15, which preceded it into Venus orbit by one day. Yawnski.
Photographs Taken: Unknown
Mission Ended: July 1984
Termination of Probe: Unknown

Vega 1

Launched: December 15 1984
Reached Destination: June 11 1985
Type: Flyby/Atmospheric/Lander
Nationality: Soviet (Russian)
Results: Not much, due to high turbulence on the planet
Photographs Taken: None*
Mission Ended: January 13 1987
Termination of Probe: Orbiter in heliocentric orbit still; descent craft likely crushed, and a balloon capsule could still be merrily drifting through the lower atmosphere, for all we know. Or it may have burst, or crashed.

Note: after completing its mission on Venus, the orbiter headed off to take a butcher’s at Halley’s Comet.

* Because they landed at night, but apparently the probe took 700 shots of Halley’s Comet.

Vega 2

Launched: December 21 1984
Reached Destination: June 13 1985
Type: Flyby/Atmospheric/Lander
Nationality: Soviet (Russian)
Results: As Vega 1
Photographs Taken: None*
Mission Ended: March 24 1987
Termination of Probe: In, you guessed it, heliocentric orbit

Magellan

Launched: May 4 1989
Reached Destination: October 10 1990
Type: Orbiter
Nationality: American
Results: Mostly mapping of the surface of the planet, which, with new high-resolution cameras was discovered to be volcanic, relatively young, with no plate tectonics or wind erosion.
Photographs Taken: Yes, but number unknown
Mission Ended: October 13 1994
Termination of Probe: Crashed on Venusian surface

Note: Magellan was both the first return to exploration of space by America in eleven years (while the Russkies got well ahead of them) and the first to be launched from the new Space Shuttles, this one being carried on Atlantis.
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Old 08-18-2021, 11:31 AM   #19 (permalink)
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Galileo

Launched: October 18 1989
Reached Destination: February 10 1990 (when I say destination I mean of course Venus, though this probe was on its way much further out of the solar system, heading for Jupiter)
Type: Gravity assist
Nationality: American
Results: Not really sure; it only flew by Venus, and its main objective was Jupiter, so there isn’t much about what, if anything, it did as it passed the second planet from the sun.
Photographs Taken: Unknown but probably none
Mission Ended: September 21 2003
Termination of Probe: Crashed into Jupiter

Cassini

Launched: October 15 1997
Reached Destination: April 26 1998 (as above; main destination was Saturn)
Type: Orbiter
Nationality: American
Results: None; seems to have used Venus, and Earth, as slingshots to get to Saturn.
Photographs Taken: None
Mission Ended: September 15 2017
Termination of Probe: Crashed into Saturn

MESSENGER


Launched: August 3 2004
Reached Destination: (as in, Venus) October 24 2006. Performed two flybys, a second on June 5 2007
Type: Gravity assist
Nationality: American
Results: Original flyby, nothing, as the position of the Sun inhibited radio communications. Atmosphere of Venus was imaged and studied on second flyby.
Photographs Taken: Yes, but number unknown
Mission Ended: April 30 2015
Termination of Probe: Crashed into Mercury

Venus Express

Launched: November 9 2005
Reached Destination: April 11 2006
Type: Orbiter
Nationality: European
Results: Longest - at that time - continuous study of the atmosphere of Venus from orbit. Original mission covering 500 days extended five times. Global maps made of the surface temperatures, surface characteristics of the planet studied as well as the plasma environment. First ever European space probe. Ozone layer detected, as well as cold areas in the atmosphere where it is postulated ice may form.
Photographs Taken: Yes, but number unknown
Mission Ended: December 16 2014
Termination of Probe: Crashed into Venus.

Akatsuki

Launched: May 20 2010
Reached Destination: December 6 2010, but failed to achieve orbit. Was eventually sorted December 7 2015.
Type: Orbiter
Nationality: Japanese
Results: After a five-year wait, the probe, the first ever Asian and first ever Japanese mission, finally achieved orbit in 2015. Akatsuki began observing cloud and surface of Venus, as well as its weather, and to investigate the claims of lightning there. Gravity wave detected in the winds above Aphrodite Terra, one of the two highland plains. Released the experimental solar sail IKAROS.
Photographs Taken: yes, but number unknown
Mission Ended: Still active
Termination of Probe: n/a

IKAROS

Launched: May 20 2010
Reached Destination: December 8 2010
Type: Flyby
Nationality: Japanese
Results: None, other than it’s the world’s first ever solar space sail!
Photographs Taken: None
Mission Ended: Still active
Termination of Probe: n/a

Shin’en

Launched: May 20 2010
Reached Destination: December 2010
Type: Flyby
Nationality: Japanese
Results: None; spacecraft failed after launch and though it flew by Venus, no communication has been possible
Photographs Taken: Unknown
Mission Ended: n/a
Termination of Probe: n/a

An interesting and unique experiment, Shin’en was a joint project between Japanese universities and I guess, certainly in terms of Venus anyway, was the first space probe launched which was not under the control of or financed by a national government. It was to be used to test the robustness, or otherwise, of computers built by the University, but contact was lost very quickly and now it’s probably up there, looking for someone to transmit data to.

Okay, wait what? I don’t get this. It says the dimensions of the probe are about a foot square, and this structure carries a payload of SIX computers? How small can those guys make the things? Answers on a postcard please...

Parker Solar Probe

Launched: August 12 2018
Reached Destination: October 10 2018
Type: Gravity assist
Nationality: American
Results: None; it seems to be another using Venus as a slingshot to get somewhere else, this time the Sun. It’s enough to give a young planet an inferiority complex!
Photographs Taken: None
Mission Ended: Still active
Termination of Probe: n/a

BepiColumbo

Launched: October 20 2018
Reached Destination: October 15 2020 (Venus, on the way to Mercury)
Type: Gravity assist
Nationality: Japanese/European
Results: None as yet; possibility of detecting phosphine
Photographs Taken: None
Mission Ended: Still active
Termination of Probe: n/a

This would appear to be the first ever collaboration between two continents, Asia and Europe, in space exploration; certainly the first involving Mercury, which is where the probe is headed. It’s expected to flyby Venus again in August of this year (2021) and arrive at Mercury sometime in October.

Solar Orbiter

Launched: February 10 2020
Reached Destination: December 2020 (Venus)
Type: Gravity assist
Nationality: European
Results: None; it’s a solar probe
Photographs Taken: None
Mission Ended: Still active
Termination of Probe: n/a

And that’s it for our exploration of Venus so far. No less than six probes are in development between 2023 and 2030, the first of these being a private US concern, then there’s one from India, one from Russia (no longer the Soviet Union, and seeming to have abandoned its observations of Venus since the original glut in the last half of the twentieth century) and another European one, with NASA chafing to get theirs into orbit too. Beyond that, a total of nine proposed missions, some only in the drawing board stage, are being looked at, all except one being NASA’s baby, including one intended to be the first rover on Venus.

It should in all fairness be pointed out that though Americans believe their country the best in the world (well, some of them do) the Russians, or at least the Soviet Union have them beat in space on almost all fronts. Leaving Sputnik aside, ignoring Yuri Gagarin’s historic feat, look at the probes they sent to Venus. They were the first to land on another planet, the first to send back pictures of the surface, the first to record sound, the first to send back colour pictures, the first to observe gamma-ray bursts, the first to observe lightning, the first to confirm Venus even had a solid surface. Oh yeah, it’s all down to the Russkies.

To be fair, there weren’t too many surprises for me with Venus. I’ve read and heard a lot about it, and most of the information is reasonably current, so while I learned new stuff about it of course in going into detail about it, I didn’t have the kind of revelation I had with Mercury, about which I knew little prior to researching it. I was intrigued by the ideas for terraforming it, sure, but that’s not quite the same. So as far as familiarity is concerned, I think I knew Venus quite well.

And now it’s time to engage the ion engines and move on.

Harmless.

Hey, what did you expect? I’m not going to spend time describing your own planet to you, the one on which you’ve lived all your life! If you want to know more about Earth, get off your arse and go explore it. You don’t need a spaceship for that. Oh, very well.

Happy? No? Tough. Look, we’re only making a brief stop-off here so that Marie can feed her cat and Batty can collect some more comic books. And those of you who have to use the zero-G toilet can you PLEASE get it right? I am tired of encountering floating turds in the air every time I walk in. Read the manual. Thanks.

Right, our brief return to our homeworld over, it’s time to - where is Dianne? Did anyone see… oh, there you are. Didn’t you see there at the back. Right, is everyone here? Let’s head off then. We're about to encounter our first ever moon. And you know what it's called?
Yeah.
The Moon.
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Old 10-10-2021, 07:09 PM   #20 (permalink)
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IV: Magnificent Desolation: The Moon

Even if you have not the least interest in astronomy or the Heavens, we’ve all seen the Moon in the sky. It’s impossible to miss, unless you happen to stay indoors and never venture outside at night, or only go out when the cloud cover is thickest. And even if so, you’ll still have seen it on the telly. Of all the celestial objects written about, it’s probably the one most featured in song, story, poetry, movies and television, and music. Even perhaps moreso than the Sun, the Moon has a certain romantic attraction for us, if only because it is the biggest and brightest thing in the sky at night, and so has become identified with night-time pursuits, from smuggling and robbery (to the practitioners of which it is an unwelcome intruder) to romance (where it is usually welcome). It’s a backdrop to the night for us, something across which bats or birds or - occasionally - a boy on a bicycle with his pet alien - travel, silhouetted briefly by the pale yellow disc. It’s been described as looking down, hiding, sailing on the clouds and many other poetic and lyrical themes have been afforded it.

It’s also the only - at the time of writing - other body in our solar system to which we have physically travelled ourselves, and on which we have set our feet. It represents humankind’s first tentative gropings out in the dark, our brief escape from our home planet, and our first manner foray into space. It exerts more than a romantic or fascinating influence on us though. The Moon controls the ebb and flow of the tides, allowing the Earth’s oceans to be regulated, and of course it usually lights up our night sky, a sort of natural light bulb that throws back the veil of darkness which would otherwise swallow us for anything from ten to twelve hours a day. It’s the nearest object to Earth, and therefore appears as the largest celestial object in our night sky, occasionally also visible during the day at certain times of the year and at certain latitudes. It features, not surprisingly, in most ancient mythologies, in which it is almost universally seen as being female, from Diana to Selene to Inanna, and usually the pale consort of the great god of the sky and ruler of the day, the mighty Sun.

The Moon is also said to exert a strange influence upon certain people, causing mood swings and sometimes madness - hence the term lunatic - and in legend invokes the process of lycanthropy, where someone bitten by a werewolf is doomed to become one at the rising of the full moon. As it rotates around the sun - taking roughly twenty-eight days to complete a rotation - the amount of visible light varies, showing in different aspects as seen from Earth, from a tiny sliver (new moon) to a full sphere (full moon). Here’s a cool video for kids that explains and shows the phases. Hey, it’s about our level, right?


Our home planet is the only one in the solar system with just the one moon, and though there are several theories as to how it formed, the mostly accepted one is that a large planet or body the size of Mars impacted the Earth about four million years ago (ah I remember it well!) and the resultant debris, formed in a ring around Earth, eventually coalesced into our own natural satellite. This is known in astronomical circles as the “giant impact hypothesis”. The Moon has no atmosphere or course, and originally was much closer to Earth than it is today, hanging huge in the sky above us, but over time tidal friction caused it to move further away, till it occupied the distance it does now, about 239,000 miles away.

Gravity is much lower on the Moon than on Earth, as anyone who has watched the Apollo missions will know, those of us old enough to remember Armstrong and Aldrin bouncing along as if they weighed nothing. Basically a big iron rock, the Moon has volcanic craters - one of them being the second-largest confirmed impact crater in the solar system - and ridges, and areas in between known as “maria”, Latin for seas, such as Mare Tranquilitatis and Mare Imbrium etc. Without an atmosphere to slow down and burn them up in, meteorites and asteroids have marked the surface of the Moon with many large craters, giving it a pock-marked appearance that can be seen almost with the naked eye, but certainly through a telescope. This probably gave rise to the old idea of the “Man in the Moon”, the face formed by features such as craters and maria.

Although it was believed there could be no water on the Moon, recent research suggests that, rather like Mercury, this may exist in some form, perhaps as ice, in areas near the poles which are in constant shadow. The Moon is surrounded by a permanent dust cloud, from the millions of comet particles that strike the surface, estimated at about five tons a day. With no wind to move them around and no atmosphere to absorb them, they remain above the surface of the Moon, rising to about 100 km. The coldest temperatures ever recorded in the solar system are not on Pluto, but the Moon, in dark, frozen caverns at the poles, where the temperature has been measured at - 238 degrees Celsius at the south pole and - 247 at the north.

Lunar Eclipse

We’ve discussed solar eclipses in the chapter on the Sun, but there are of course lunar eclipses, when the Moon is in Earth’s shadow and the two objects are more or less in a direct line with the Sun, in what is known as a state of syzygy. Because it is far closer to the Earth, though much smaller than the Sun, the Moon appears during a lunar eclipse to be the same size as our native star, and so can “block” it. Lunar eclipses only occur during a full moon, and unlike solar ones can be watched with the naked eye as they are nowhere near as bright. The moon at full eclipse does not turn black, as it does in a solar one, due to the sunlight passing through Earth’s atmosphere and being refracted, giving it a reddish colour, often called a “blood moon”. This is also used in Christian belief to signify the expected Second Coming of Christ and the Rapture (Judgement Day), tied in to a passage in the Book of Revelations in the Bible where John mentions the moon turning to blood.

Unlike solar eclipses, which occur but rarely, lunar eclipses happen at least twice and sometimes five times a year, though few of them are total eclipses.
Lunar eclipses were of course viewed with suspicion, dread and fear by our ancestors, most of whom believed some sort of beast or demon was swallowing or eating the moon, and it could only portend bad times ahead. The Hindus, though, believed that bathing in the Ganges after a lunar eclipse was opportune, as it would help them achieve salvation. Why? I have no idea. Ask them. A rather amusing, in a dark way, story comes from the Mesopotamians, always good for a laugh, who believed that a lunar eclipse was the result of seven demons attacking the moon, and fearful that the demons would then turn upon their king, they got someone to stand in so that he would be attacked instead of the king. Once the eclipse was over, this helpful gent was poisoned. I doubt there were too many applicants for that job!

As late as the nineteenth century, the Chinese were still trying to ward off the dragon who was believed to eat the moon, and while traditionally this had been achieved through the ringing of bells, these modern lads used navy artillery to scare off the big lizard. That’ll show it who’s boss round here!

Moonwatching: Early Observation


Being the closest and most visible celestial object, the Moon has of course been studied since antiquity, and while Americans may have been the first to tread on its surface, I’m proud to say that the first ever depiction of the moon is in Ireland. In a burial passage in Knowth, in Drogheda, there is a representation on a rock which is believed to date back about five thousand years. In your face, America! Of course the Babylonians, well known historical and scientific eggheads, had been studying the Moon since the fifth century BC, and those clever Chinese were already able to predict lunar eclipses a century later, and in 428 BC Asterix sorry Anaxagoras, an ancient Greek astronomer, sussed that the Moon was a big rock in space, and so was the Sun. Well, one out of two ain’t bad.

A pretty big deal in the second century BC was when Seleucus of Seleucia (did they name the city after him, or him after the city I wonder?) worked out that tides were controlled by the Moon. I mean, this was before anyone knew what a telescope was, or even what the Moon truly was. That’s mighty impressive. Not to be outdone, Aristarchus (who did not found Arista Records) gave working out the distance to the Moon a shot, and got it reasonably accurate, though later Ptolemy brushed up his figures and got more or less the correct measurement.

And then came our mate Galilieo.

It will come as no surprise to anyone that the Italian father of astronomy made big inroads into our understanding of our nearest and only satellite. He used his cool new invention, the Galileoscope (well, the telescope then), to make drawings of the surface of the Moon, and could prove that it wasn’t, as his predecessors had all thought, smooth and without features. In fact, he detected craters and basins and mountains, though it would be another two hundred and fifty years almost before a proper geological and topographical map of the Moon could be produced.

Because the Moon is in synchronous rotation with the Earth (you surely don’t need me to explain that term, do you?) the same face is always turned towards us. This gives rise to the idea of a dark side of the moon, but as yer man says on the Pink Floyd album, there is no dark side, it’s just that we only see one side, and so the other seems dark to us all the time. The actual, proper term for the two sides of the Moon is the near side and - wait for it - the far side. Although the Moon has no tectonic plates to crash into and move against one another as they do here, causing earthquakes, tidal stress means that there are frequent “Moonquakes”, though usually nothing on the order of even mild ones on Earth.
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