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Tuesday 28 July 2015


Berlin ! The city of.... uhh, the Brandenburg Gate ! The Berlin Wall ! And probably some other stuff, too, I shouldn't wonder... Naturally, when invited to visit a friend on an internship in Berlin, I jumped at the chance. How could I refuse the chance to visit somewhere with both famous landmarks ?

So I found an inexpensive hotel - Berlin, somewhat surprisingly, is full of them - booked a bus ticket, and filled my suitcase with 10 litres (17.5 pints) of beer. Why on Earth would I take beer to Germany, I hear you ask. Isn't that like taking coals to Newcastle ? Not if your friend is Czech, it isn't. To suggest to a Czech that any other nation's beer is superior is like calling a Glaswegian English or telling an American that guns are really actually quite dangerous things and they should put them away. It's not something you want to do if you value your continued existence.

Anyway, said friend has been teaching me how to drink beer, a statement which is likely to have given several long-term readers heart palpitations. In fairness, there are - it seems - many beers which do not have the disgusting aftertaste that makes me think beer drinkers are otherwise completely mad.

Hauling near enough twenty beers up several flights of stairs was somewhat gruelling work. I was rewarded with a rather fine sunset at the train station in Berlin shortly after my arrival.

Unfortunately the pleasant sunset was in no way compensation for the massive inefficiencies of the Berlin public transport network. Instead of taking 30 minutes to get to my hotel it took an hour. Much worse than this was that instead of simply delaying the train from reaching the station, the train simply stops at the station. Everyone gets on.

Then the train doesn't go anywhere.

The train continues not going anywhere for about 15 minutes.

Yep, that's right, it just sits there.

It's 37 degrees Celsius and at this point it was still full daylight. It was not fun.

I also soon noticed other flaws in the public transport system. The front of the train labels the destination, but of course you only see that for a moment as it rushes past. Inside the train (or bus) the electronic screen doesn't say anything until the train leaves the station, so for a confused tourist it's of little help. When it does move, it only says the next station, not the final destination. And often it just doesn't work at all, and in one case it got stuck after about three stations.

The good news is that to get through this muddlesome mess, God created the German people. Anyone even looking like they might possible have any doubt is sure to rapidly encounter an extremely helpful German person who will make sense of it all, or at least try to. You don't even have to ask for help, just look slightly confused and someone will soon get your sorted out*. Perhaps the Berlin transport network was designed knowing that it wasn't necessary to make it simple to use because the Germans would happily explain it to everyone who didn't get it.

* I've begun to wonder if this would work in other circumstances. Like, if I could contrive an expression that very clearly says, "I'm really not sure if my smooth particle hydrodynamic code is giving me numerical artifacts or interesting results", maybe a German person would just magically turn up and explain it.

Eventually I reached my hotel and the situation rapidly improved. I was given a free upgrade to a larger room, for no reason, and though the air conditioning was underpowered the room was at least 15 C cooler than outside so my brain was able to re-congeal into something basically functional once again. Really, the last time I was this sweaty and disgusting I was in the frickin' jungle.

No, I'm not wet because I went swimming. Yes, I know that's disgusting. Topical paradise, my foot.
Shortly afterwards I began another full hour of travelling to reach the visitor's rooms near the DLR, where I was treated to a delicious Czech meal of potato pancakes followed by beer and more beer. I made it back to the hotel around about 2ish, where after a full eight hours of travelling (and precious little sleep the night before for some reason) I swiftly collapsed.

I suppose just for the sake of comparison I should also mention that the brief riverisde walk outside the hotel the next morning was a lot nicer than the harrowing death march to reach the Tanama river in Arecibo. It wasn't anything special, but at least when I took this photo I didn't feel like I was starting to liquefy. Unfortunately, I've lost most of my tropical climate adaptations, which means I'm back to complaining bitterly whenever it gets over 30 C.

I met up again with my Czech friend and housemate-whose-name-neither-of-us-can-pronounce for lunch (bratwurst) by the Brandenburg Gate. Gosh, that sounds classy, doesn't it ? It should. It's a classy place.

This being my first full day in Berlin, wandering around the city center was essentially obligatory. And a very nice place it is too. I mean, it's not Cardiff, or even Prague, but it is well worth seeing. Just around the corner from the Gate is the Holocaust Memorial. It is, of course, right and proper that a huge piece of real estate, in the center of what is essentially the capital of Europe, is given over to recording one of the worst atrocities in human history.

... but on the other hand the monument itself perhaps does not command the air of solemnity its designers probably had in mind. In the above picture I've recoloured it to give it some sense of atmosphere, but on a bright sunny day it isn't like that at all. Signs say "no jumping from one stele to the next", which is a rule continuously flouted because most people are, at heart, about five years old. And that's a good thing. Maybe it's even the reason we haven't gone extinct yet.

A little further on from this we came to Potsdamer Platz in search of the Cafe Gelato. Which we found. We also found part of the Berlin Wall and a small exhibition about it inside the shopping center.

Leaving the British sector ? Hah ! I AM the British sector !
Yeah ? Well, screw you, sign ! You're not the boss of me !

As shopping centers go, it's tough to beat having part of the Berlin Wall just outside and an exhibition about it inside. It really is astonishing to consider the scale and speed of the changes that have happened so recently. Less profoundly, it also had really good ice cream - although you weren't allowed to sit at a table to eat it. Because walking around with melting ice cream is obviously a much better idea.

From Potsdamer Platz we headed back to reach the Berlin Victory Column. Along the way we encountered the Soviet War Memorial.

The memorial is flanked by two tanks and small artillery pieces. Presumably the Soviet artists, like their later German counterparts, saw no reason a monument to some utterly horrific events couldn't also be a) intimidating and b) fun for tourists decades later. Because who's going to resist the chance to pose with a tank, right ?

Glamorous blonde scientists don't often pose with tanks for your amusement.

Moving swiftly on, the Victory Column. It's a dramatic sight - 67m tall, built to celebrate three 19th century German (Prussian) victories against the French, the Danes and the Austrians.... none of which I know the slightest thing about. I doubt anyone else does either. That would be like visiting Big Ben because you're fascinated by clockwork - entirely legitimate, sure...but, well... weird.

After the Victory Column, the TV tower. We didn't go up - it's expensive - but it is impressive to see, and less ugly than Prague's giant space rocket covered in deformed babies with giant heads (that is its official name). What I would have liked to have seen is the dome of the Reichstag, but unfortunately it was already fully booked for the weekend.

The church is one of the oldest in Berlin.
We ended the day near what I'm calling the half-church... because it's half a church. And whadayaknow ? Typing, "Berlin half church" into Google finds the correct result. It's great looking building, but it's almost a shame it's in Berlin. It would have made for a perfect movie location if it was out in the countryside somewhere.

However, as far as awesome movie locations go, the next day won hands down. Unlike the above, you won't find Teuflesberg listening station on any "must see in Berlin" lists. And I have absolutely no idea why, because it's an extraordinary place. It was just about visible from the Victory Column so we decided to try and get there.

I reserved a place online... but here's a word to the wise - I really don't think it's necessary. Their website may look flashy on a tablet but it's very amateurish on a regular PC, and I seriously doubt the place even has internet access. They probably just check their email on their phones. Also, though their site says the tours stop at 4, this didn't seem to be the case either. If you can't get there by 4pm, I'd email or call them to check. Possibly you do need a reservation for the 2.5 hour guided tour (weekdays only, once per day), though.

A bright white geometrical dome poking through the forest... quite a familiar sight, in some ways.
Teuflesberg ("Devil's Mountain") is an artificial hill 80m high built from the rubble of Berlin after the war. It's named after the nearby Devil's Lake, although it even has a rather fiendish connection of its own, despite being only a few decades old. I didn't have time to read up on it beforehand, but the wikipedia article is quite fascinating :
Its origin does not in itself make Teufelsberg unique, as there are many similar man-made rubble mounds in Germany (see Schuttberg) and other war-torn cities of Europe. The curiousness begins with what is buried underneath the hill: the never completed Nazi military-technical college (Wehrtechnische Fakult├Ąt) designed by Albert Speer. The Allies tried using explosives to demolish the school, but it was so sturdy that covering it with debris turned out to be easier. 
OK, so it's an artificial hill that covers the ruins of a Nazi military college. Appropriate name after all, then. Apparently the forest is also full of wild boar.

From the approach we took, the listening station "Field Station Berlin" was rarely visible through the forest. A very nice forest it is too, though methinks some of the holiday homes take their security a tad... seriously ?

Maybe those wild boar can jump.
Even when you reach the hill - after a brisk 45 min walk or so - you can't see much from the entrance. The site is now a sort of reservation for graffiti artists, presumably to keep them safe and protected from the real world. Which is exactly the same function universities serve for scientists.

The angry dog will guide you on your mystical forest journey.

OK, the scrawls at the front aren't up to much, though I did appreciate the ironic angry dog. But pretty soon you're rewarded with real artistry. It varies in quality, of course (not all of it was to my taste), and it certainly isn't family friendly. Much of it isn't friendly to anyone. In fact I would even say it's overtly hostile, but almost all of it is interesting.

Graffiti ? No, it's the original colour, honest.
Generally good advice.

Some of the doodles are little better than what you get scrawled on the side of a subway (though at this point I have to point out that Cardiff's graffiti can be amazing, seriously click that link). And some of it is genuinely good art.

Immortan Joe's forest-dwelling cousin ?

I was almost half-expecting just to be able to walk around the site, because the buildings are not in a good condition. But, nope, you get everything. Right to the top of the tallest tower*. You don't get much in the way of hearing about the history or function of the building, unfortunately, but what you do get is a graffiti art gallery built in the ruins of an NSA listening post built on the ruins of Berlin built on a Nazi military college. And come on, that's tough to beat for 7 Euros.

* Is it safe ? Well the guide described it as being "not idiot proof" which I take to mean "hell no".

The title of this painting is definitely, "Giant naked sea goddess attacks defenceless island using giant swans". Definitely.
"Fuck condoms" ought to win an award for irony.

At the top, the geodesic domes. The outer fabric is half-ripped away and billows in the wind, making the whole place sound like you're inside a giant tent with a view of the whole of Berlin. Actually what I was most impressed with was not Berlin itself (which is fine enough) but the fact that in some directions the forest stretches right to the horizon.

A.k.a the forest moon of Endor.

OK, it was an NSA listening station, so perhaps the anti-America stuff is to be expected. Still, I don't really get it... or the "freedom is beautiful like a brick in the face of a cop" slogan*, or the various anti-Obama messages. I mean, come on people : you've been given this huge structure overlooking Berlin as a toy ! And you've been allowed to do this by the system you're against ! It just strikes me as incredibly self-righteous and suffering from a massive dose of the Nirvana fallacy. If you've been given somewhere like this to do what you love, and all you can express is anger at the system, well... aaargh. Maybe I'm just not taking it as tongue-in-cheek enough.

* Thus spake the angry dog. I preferred his other slogans, "The man who does not read has no advantage over the man who cannot read" and especially, "Who left the bag of idiots open ?".

That's enough ranting. The finale at Teuflesberg is the very top of the tallest tower, where the dome is completely intact. It's lit only by a single window and you're greeted on entry with open arms :

But the weirdest thing by far is the sound. The acoustics in the dome are... well, awesome. Wherever you stand, any noise you make is reflected back to you - loudly. It's like listening to your own voice through a microphone and speakers, without the microphone and speakers. When we entered the dome it was filled with a cacophony of  whoops, whistles, laughing, animal noises... everything, really. I only wish I'd thought to record it sooner, but it was a such an arresting experience that it seemed more important to just listen.

The center chair is even more remarkable. Despite the din, any sound you make in that spot becomes audible to you but not necessarily anyone else. I looked on in bemusement while my friend just sat there, tapping her foot. Foolishly I yelled at her to say something. She kept tapping her foot, grinning like a crazy person*. Only when I tried it for myself did I finally understand - this extremely quiet sound becomes massively amplified to anyone sitting on the chair. It can't be recorded, you have to experience it. Lord knows what music would sound like at that spot.

* Oh thank Gods for anonymity.

Teuflesberg, then, ought to be very high on anyone's must-see in Berlin list. The only thing you don't get on the one hour guided walk is much in the way of any historical information about the place. I can't vouch for the 2.5 hour tour but if I ever go back there for more than a weekend (why this option is weekdays only I have no idea) then this would be top of my list.

This extremely pleasant, more sedate day was followed by more delicious Czech food* and quite a lot more beer. I reached my hotel room around 3:30am, learning the hard way that the S-Bahn doesn't run on Sunday evenings ! Although really it was Monday morning... grrr.

* Fried cheese. The Czechs have great sympathy for vegetarians, and they're determined that they should be able to enjoy incredibly unhealthy fattening food as much as the rest of us.

Anyway, though its public transport service doesn't hold a candle to Prague - I suspect nowhere does - Berlin is a fine city, completely different to Prague or Vienna. While I wish Teufelsberg had provided a bit more information on the place, being kept as a reservation for graffiti artists gives it really unique character. Maybe that angry dog should occasionally quote snippets of interesting information about the place. He could even keep his trademark anti-capitalist, anti-American ranting, I wouldn't mind it so much if I got a bit of an education as well.

Tracing the outline of the angry dog took a surprisingly long time for a cheap joke, but meh.

Sunday 26 July 2015

It's a planet, DEAL WITH IT.

A zebra is a type of horse. A lion is a sort of cat. A PC is a type of computer, and a platypus is a particularly weird mammal. A dwarf, without any other qualifying description, is a person.

But apparently Pluto is not a planet, because dwarf planets somehow aren't planets.

NGT and I got off on the wrong foot. For American readers, NGT is not much of a thing in the UK (neither was Carl Sagan actually). I've never got on with his I'm-delusional-with-excitement-about-everything attitude, and the first time I ever saw him on TV he was ranting with a pointless, surprisingly humourless fiery passion about why Pluto isn't a planet. I instantly failed to take him seriously.

The trouble is - amongst other things - is that such an uncompromising attitude is not conducive to rational debate. In fact it encourages the exact opposite, hence this post.

There are lots of different sorts of stars : yellow stars, red stars, blue stars... all are stars. No-one disputes this. There are grey areas like brown dwarfs, which don't shine by nuclear fusion, but, in most cases, one can look at a big bright shiny thing and say, "yep, that's a star". One can then go on to specify exactly what sort of star it is. And of course the same can be said for horses, cats, computers, and so on.

Image credit : me.
But not planets, apparently. That's because the IAU's definition of planet is - linguistically if nothing else - dreadful. Instead of defining different types of planets, it says that some things are planets and others are merely "dwarf planets". How can you have a dwarf thing that isn't a type of that thing ? That's like saying that dwarfs aren't people.

All dwarf planets are bastards in the IAU's eyes.
Then there's this bizarre idea that what a thing is depends on its environment - the famously ambiguous part of the definition that says a planet "must have cleared its orbit". Which Earth and Jupiter haven't, for instance. Now "moon", well, OK, but we all know what a moon is - something orbiting a planet. Being a moon isn't somehow demoting that object just because it happens to be orbiting something else. "Moon" is really only a specification of what the object is doing, not what it fundamentally is. The moons of Mars are likely captured asteroids; no-one thinks they've become magically different just by orbiting a planet.

But "planet" is different. We use it to distinguish it from other, very different objects like comets, nebulae, stars and galaxies. Saying that "planet" depends on its environment is like saying that someone could be counted as a dwarf if all their friends are very tall. It's nuts.

He's no Tyrion Lannister, that's for sure.
I propose a much simpler system. Sure, there will be grey areas, just like everything else, but here's a stab at something that should work well enough most of the time.

Let's use "planet" to mean anything that is large enough to be round but not so large that it shines by nuclear fusion. We'll have to agree on a precise definition of "round", but that's something of a detail. Anything smaller than this would be a comet or asteroid or possibly a stellar remnant.

The key is not to stop there. Instead of "planet" and "dwarf planet" we should have "giant planet" and "dwarf planet". Thus, both are very explicitly on equal footing. They are both types of planets. No inferiority is implied, they're just different, just as a whale isn't any better than a mongoose but both are mammals*. We could also have "terrestrial planets" and "gaseous planets" or even "ice planets". Yes, this would mean the Solar System would have a lot more planets, but it wouldn't have any more major planets. We can make as many sub-categories as we like, and make them as complicated as we like. We could even allow some moons to be types of planets.

* One may of course argue that the same is true of the current definition of planet/dwarf planet. Perhaps this is true, but I think it's a lot clearer if you label the giant planets as giant planets, not just planets.

Some people like to point out that Pluto would have a tail if it was closer to the Sun, and therefore it's not a planet but a giant comet. Uh, yeah, well, Earth would have a tail if it was close enough to the Sun. Anything would, because the Sun is jolly hot. We've known about Jupiter-mass evaporating planets for over ten years. No-one's claiming those are giant comets, because that's just plain silly.

Of course, there are very important fundamental differences in both composition and formation mechanism of the various "planets" in this system. Pluto orbits above the plane of the other planets, sure, but so what ? This taxonomic system in no way prevents you from classifying things in a very specific, detailed way : Pluto might become a "giant non-ecliptic minor ice planet", or something. But you retain the word planet to mean something that's already widely-accepted without confusing the heck out of the general public. You instantly convey to people that you're talking about a big round thing that's within a certain size range and not a star*. Which is surely the important thing.

* And of course we've been using terms like "gaseous planet" and "rocky planet" for decades, without confusing anyone. Again, the only reason people object to "dwarf planet" is because it's somehow not supposed to be a sub-category of planet but a distinct object.

Having a funny orbit shouldn't matter to what we define as a planet. Planets can be tidally ejected from their star systems altogether to become rogue planets - they don't stop being planets, they are now just, like moons, doing something a bit different (it's possible that some rogue planets might even form without a star at all - we don't really know as yet).

And no, being in the asteroid belt does not automatically make something an asteroid, any more than going into Church makes one a Christian. Ceres is, maybe, a small planet that happens to be in the asteroid belt. Sure, it may just be the largest asteroid - and here's where we reach a grey area. We don't really know what the difference between a planet and asteroid is (things are even worse when we include comets). But, while the proposed definition of planet may be unambiguous, being able to define-sub categories gives a lot of flexibility. As we learn more, perhaps we'll define the largest asteroids to be a special class of planets. So we haven't restricted ourselves in any way with this wide-ranging definition.

The spectacular results from New Horizons don't really make any difference to whether Pluto is a planet or not, but they do emphasise that this is a world. "Dwarf planet", given that "planet" is a separate term, sounds somehow condescending and just plain weird.
The point is, stop trying to say things aren't planets when they are quite clearly just different varieties of planets. Maybe they are radically - perhaps even fundamentally - different varieties of planets, but this broad definition doesn't prevent us from labelling them as such when we know enough about them (just as a whale is really quite a radically different animal from a mongoose). Right now, we don't have that information.

People also ask why people are vitriolically concerned about Pluto but don't give a monkeys about Ceres or other large Solar System bodies. Well, OK - but isn't this attacking the motivation rather than the argument ? Sure, Pluto is far more of a poster child than Ceres because History, but that doesn't mean we shouldn't re-evaluate our definitions.

Does any of this matter ? Yes and no. It doesn't really matter as far as the science goes because what you label something as doesn't change what it actually is. However, "stars and planets" are the two things most people think of when they think of astronomy. If we can't agree on the definition of "planet", then we look a bit silly. And it seems to me that a bit of common-sense understanding of the English language offers a simple way out of this unnecessarily complicated mess.