ESCAPE !

Or Why I'm Taking a 75% Pay Cut For Science

You'll note the banner change today as I officially accepted a job offer from the Astronomical Institute of the Czech Academy of Sciences. Physicists of the Astronomical Institute of the Czech Academy of Sciences somehow lacks a certain punch, so long-term I'll probably go with Physicists Formerly of the Caribbean. I may or may not keep the Arecibo background, I haven't decided yet.

For those reading this years after the event, here's the temporary banner.

I've been determined to leave Arecibo for some time, having applied for jobs for around the last nine months (it's just a coincidence, I swear !) and received about a dozen rejection letters (which is actually doing pretty well). For the non-scientist readers, a normal academic career path consists of two or three postdoctoral appointments (usually in different institutes) followed eventually by a permanent position - usually lecturing, sometimes pure research.

This expectation that as a postdoc you're supposed to drop everything and start a series of new lives across the world is one of the best, most awful and bizarrely pointless aspects of the typical astronomy career path. All of my family and 90% of my friends (99% of the really important ones) are back in Europe, so why the hell would I want to live over here ? That would make no sense. The situation is made even worse for me because I don't like (read : detest) driving, and since there's no public transport (?!?! seriously, WTF, Puerto Rico !) the sense of isolation can be crushing. I mean, come on, I don't even like the climate.

So new horizons beckoned, and while I applied for a few jobs in the States, Europe was the goal. Being offered a job gave an instant and unbelievable sense of euphoria. This was rapidly tempered by the salary, which is above average in the Czech Republic but not enough to make any meaningful savings that I could use elsewhere (it's lower than what I was earning as a PhD student in the UK). I spent several days thinking very carefully and unusually seriously about whether this was a good idea.

Quite quickly, though, I realised that it was a damned good idea. I'm not fussed on fine dining or flashy cars (obviously) or palatial houses (though I'd like one with a bath next time, if it's not too much trouble). Really, when you get right down to it, I just want to be able to take my dog for walks. And that doesn't cost a damn thing.

Everybody say "d'aaaawwwwww".

Still, while I don't think I should buy a boat, I am very conscious of the need for financial security. Which makes Prague a risk, but a calculated risk. Not taking any risks at all is for losers. Taking wild, crazy risks ("let's jam the fork in the toaster to see what happens !") is fine if your ambition is to win the Darwin Award.

The risk of Prague is that I won't earn any useful money for the next two years. But the savings I have from Arecibo are such that there would have to be a really spectacular disaster before that became a problem, and the chances of that happening are acceptably low (things might be different if I had zero financial redundancy). In contrast, it's almost a certainty that Prague will be a better place to live, both from a personal and career point of view. So, it's a small risk of utter ruin (no more than normal, really) for a really good shot at living somewhere more awesome. Carpe diem, indeed.

I believe the phrase you're looking for is, "good grief".

Visiting home three of four times a year should be no problem as it's a $300 return flight direct to Cardiff which takes 4 hours. Compare getting home from here, where the total journey time is around 18 hours (more like 24 now there are no direct flights), costs > $1200 and involves getting over significant jet lag -  it really can't be done more than twice a year. That's not enough. I'd have to be some kind of freakin' monster to want to shun my family and friends for the sake of earning money.

The tremendous commitment required to go between Puerto Rico and the UK means I've only had one visitor in the entire two and half years I've been here. Many of my friends can't drive, thus ruling them out entirely. Yes, in principle I could drive them around the island. Realistically, San Juan airport is so far away (and I find the process of driving so intensely stressful) that it might as well be on the Moon, so that doesn't work. In contrast, driving in Prague is unnecessary because of the public transport network. So Europe is by far the best option for beating isolation.

Driving on the Moon is a lot better than driving to the Moon.

Career plans also played no small role in the decision. If the goal is to move to somewhere in Europe permanently, then actually being in Europe is an infinitely better way to make other European collaborations which may eventually lead to jobs. Staying here would mean I would become part of the woodwork - great for keeping the telescope going, but not for doing actual research. And that might be fine (given the... umm.... healthy salary this place pays) if I wanted to stay in Puerto Rico forever, but I don't.

Then, just to make absolutely sure I was subject to the maximum possible emotional g-forces, another institution (which pays far more competitively) that I didn't think I had much of a shot at decided they wanted to interview me. I took the (perhaps crazy) step of declining the interview. Prague required a decision on a much shorter timescale than the interview process, and declining a firm offer for the chance of a better one would be a really bat-shit crazy* risk (especially as I don't have much experience in the most important technical skill required for the other job). Accepting Prague and then accepting the other would be grossly unprofessional and unethical.

* Technical term.

This kind of balance is what got the world in the state it's in today, so no thanks.

Anyway, the AICAS is a research institute, not an observatory - it's within Prague itself and I can generate RFI to my heart's content (i.e. I can have wi-fi and a mobile phone again ! and I can call it a mobile rather than a cellphone ! yay !). It also has a much larger research group (Arecibo has all of 3 massively overworked staff astronomers). Not to mention that living in a city - particularly one as outstandingly beautiful as Prague - is unimaginably appealing after living in the middle of the jungle for two years (most of the buildings in Arecibo's pathetic town center are full of trees*).

*DISCLAIMER: there are some really very nice places indeed in Puerto Rico. Arecibo is not one of them.

The institute also owns an observatory in the nearby countryside, thus getting
the best of both worlds.

So Prague ticks nearly all the boxes. I can go home more often, have visitors, live in a city, never drive anywhere, do exactly the research I want to do (this is pretty uncommon for postdocs, so this is really a major perk) and form more European collaborations. I just won't be earning any (more) more money for the next couple of years. Unlike gap year students, I already have financial backup in case of emergencies. All in all, pretty sweet. Maybe I can finally get off the emotional roller-coaster and on with more important things, like selling my much-hated car. Or possibly burning it.

It would absolutely be worth every penny I paid for it. Tempting.

Blue Marbles

So I saw a picture the other day comparing the size of Earth to Jupiter. Maybe it was this one :

... or maybe it wasn't. But it was very similar. Anyway, I immediately decided there must be a more interesting way to compare the sizes of the gas giants. Merely comparing the physical size is one thing, but it doesn't tell you about how massive they are (that is, how much stuff they're made of, which is not quite the same as weight).

Let's start with the least massive of all the outer planets : Uranus (you can do your own hur-hur jokes if you like, I don't mind). There's no getting around it - this is the least interesting-looking world in the Solar System. What can you say about it ? It's... blue. And round. Quite big though - almost 4 times as wide as Earth, with a mass equivalent to 14 Earths.

I am crediting my website much more prominently than usual not because I care about copyright but because I'm sick of it having a mere 3,000 hits.

Uranus may look boring, but.... no, it's no good, it's actually incredibly dull. Apart from the fact it's tilted on its side (possibly due to a massive impact with something billions of years ago) and has wind speeds in excess of 900 km/h (560 mph). Ghastly place, with a temperature of -224 C (the coldest atmosphere in the Solar System), but one could hardly call a world-spanning ice hurricane* boring, in fairness.

* Poetic license.

On then to Neptune. This considerably more interesting-looking world is slightly smaller at 49,224 km across. It's also a bit denser, with as much mass as 17 Earths.

Neptune is an even worse place to live than Uranus. Sure, it's 25 C "warmer" (for want of a better word at -200 C) but the wind chill factor would make even a tauntaun shiver, or, more likely, die, because 2,100 km/h (1,300 mph) winds are generally pretty lethal, really.

Next we take a drastic leap in scale with Saturn. Saturn is a bit wider than 9 Earths, which is not all that much more than Uranus or Neptune. Unless you count the rings, of course, which are over 270,000 km across.

Saturn is bigger and so a lot more massive than the Uranus and Neptune, with as much matter as 95 Earths. But that's not as much as you might expect, given its size. Famously, Saturn is actually less dense than water - so if you could find a large enough ocean it would float. Though one suspects that by putting a gigantic ball of gravitationally-bound freezing gasses (-178 C*) into an offensively large ocean, something more dramatic would probably result than Saturn just quietly bobbing around.

* Things get a lot hotter - many thousands of degrees - in the core, mind you, as they do for the other gas giants.

At last we behold mighty Jupiter, largest and most pompous of all the planets with its colourful swirling gas and giant spot three times the size of Earth. It's not all that much wider than Saturn - about 20% - but it's a whole lot denser with a mass of something like 315 Earths. At a mere -150 C with winds of 600 km/h (370 mph) it's still a worse holiday destination than Port Talbot and doesn't (like the other giant planets) even have a solid surface.

You might wonder why the planets are all so different. So does everyone else. As far as I can make out, there isn't much consensus as to what went on in the early Solar System. A lot of the old theories went belly-up when Jupiter-mass planets were found orbiting much closer to their parent stars than Jupiter does. It's been less than 30 yeas since the first exoplanet was confirmed, which really isn't very long at all if you're trying to understand how the world itself came to be.

Finally, the Sun. It's gassy (plasma if you want to be pedantic, which I don't) and gigantic, so it makes the list. The Sun is only about 10 times wider than Jupiter, but massively more massive... about 1050 times as massive. Although it's somewhat difficult to pin down at exactly what point a planet becomes a brown dwarf and a brown dwarf becomes a star, there's no doubt the Sun has completely crossed that threshold and completely dominates the Solar System.

Still images are nice, but animations are better. I decided to take the "Blue Marble" name literally. Because... well, it's fun to make it rain planets.

Modelling Arecibo Observatory

Don't worry, that's "modelling Arecibo", not "modelling at Arecibo." This doesn't involve me posing in skimpy clothing in strange positions with the telescope in the background. That can be arranged, but my fee is very, very high. It does involve me in one or two weird positions and getting hot and sweaty, but for entirely legitimate reasons.

Anyway, it was bound to happen sooner or later. I can't very well work at one of the world's largest and most - dare I say it - iconic telescopes and not try to model it at some point, or I'd feel silly. Actually, I always had a long-term goal of modelling the entire site and making it into a Half-Life 2 level. It would make for a seriously perfect setting. It's got the massively complex industrial setting of the platform (with its perilous 140m drop), a road running by steep cliffs and dense jungle, and the whole complex is fenced off, making it a natural stand-alone level.

It's also got a couple of small office buildings with very narrow corridors that could become incredibly creepy at night. But best of all is the area underneath the dish, which is replete with small concrete towers (just large enough to hide behind), small wooden shacks, rusty old antennas and a large ditch that's half-full of water. The place practically screams FPS level.

Just add zombies.

Seriously, if anyone is au fait with making HL2 levels, do let me know.

But I digress. Right now there's a very specific goal (because my boss told me to) of modelling the telescope (not the accompanying buildings) and getting it laser-etched in glass. Established readers will recall that I had my thesis data etched in glass - this is very similar, except that while no-one else will want a huge chunk of glass full of blobs, they might very well be prepared to pay for a small chunk with a cute little model of the telescope inside. We'll see.

Modelling the whole site would be a formidable challenge, but even modelling just the telescope is tricky. The basic design is easy. The detail is ferociously complex.

Modelling even the basic structural layout of this is nearly impossible without extremely detailed data or, better yet, schematics. Fortunately I was lucky enough to be given some by my other boss. I probably shouldn't post these, but they're hugely detailed. It seems as though almost every joint is rendered from multiple angles. But once I had them, tracing the general structure became a lot easier.

These are not the official schematics, they're what I ended up with.
The real ones are much more detailed.

They also contain mistakes. By far the biggest is the reflector itself, which has been drawn assuming it was around 850ft across, because the artist assumed the 1000ft diameter was along the curvature of the dish, and not rim to rim as it is in reality (and yes, everything is measured in feet).

Since the dish is spherical (unlike most telescopes it's not a parabola) this was easy to correct. Other mistakes (probably not actually mistakes at all - the schematics appeared to date from the mid 90's, and things change) were more subtle. For instance, in one drawing the azimuth arm was shown as being slightly asymmetrical, with one end tapered and the other truncated. I checked some photos to see if this was the case, but quickly realised it was better to just go outside and have a look.

This was true for a lot of other details. The arrangement of cables was something I was particularly keen to get right. Trying to figure out exactly how the 18 support cables attach to the platform in 3 dimensions was nearly impossible from the schematics, so I went for a walk (actually several walks). The cables are attached to the three towers, with cables from each tower attaching to different parts of the triangle. So by far the easiest way to see where the cables go is to go and visit the towers.

I took these pictures on another day - to avoid generating RFI I drew
little schematics of my own.

Getting to the towers is not so easy. There's one at the visitor center, which involves a short but steep walk. To get to the others, you first have to go back down, then down the very steep walk to the dish, then up again another short but steep walk which is partly shady but also sheltered from the wind. Since the temperature is around 33C and the humidity 900,0000,000%, this is not so pleasant. Getting to the final tower involved crawling underneath a gate (I could have gone and got a key to open it, but meh). My way back was blocked by an impassable gate, so I went back the way I came and completed the 1km circuit of the dish, then back up the very steep hill and finally into my office.

This explains my boss' puzzled look when he found me sitting in my air-conditioned office drowning in my own sweat.

Some other details I got entirely from reference photographs because they're not on the schematics - the waveguide (which is about the size of an air vent and carries the signals from the telescope), the platform walkways, the fans on the side of the Gregorian dome... that kind of thing. These I had to do by guesswork, but the end result is at least a lot better than if they weren't included at all.

Surly-looking astronomers also aren't included on the schematics.

Then there's the terrain. This is intrinsic to the telescope; the natural sinkhole is one of the reasons it was built in Arecibo. It also means that one of the towers is a different height to the others, so getting it right is important.

Fortunately the USGS provides Digital Elevation Model data for the entire US, though only at 30m resolution for Puerto Rico. I converted this into a Blender-readable format by using 3DEM to convert it into a Terragen terrain and then Terragen to export it as a Lightwave object, which Blender can read. Convoluted, but also tried-and-tested. The 30m resolution is a real handicap though, and there was a lot of manual tweaking - the terrain in the immediate vicinity of the dish is largely fictitious.

Around the edge of the dish is the ground screen. The dish is fixed, but the instruments can be moved as much as 20 degrees from overhead by moving the receivers along the azimuth arm. At high angles, they start receiving signal from above the edge of the dish. The ground screen limits the damage this would do. That wasn't in the schematics, so I went for more walks and asked other staff members how tall it is and what angle it's at. I also simplified its structure somewhat so that hopefully it will be easily visible when etched in glass.

The support structures for the ground screen vary depending on how close it is to the cliff. Here, where the cliff is very close, the metal girders go into the cliff. In other places they're not quite so close, and join on to vertical concrete pillars. In a few places the cliff is very far way and they form tripod structures. Unfortunately the 30m terrain resolution is just nowhere near enough to attempt modelling this accurately, so I simplified everything and only modelled the tripod variant.

The business end of the telescope is the platform. Sure, the 305m reflector is great, but it's the 900 tonne structure hanging in the air that houses the instruments that actually collect the signal. In Goldeneye, Sean Beam famously falls off the 30m-long line feed before the whole thing explodes. Because the reflector is spherical, radio waves get focused to a line, not a point, so a line feed is a clever way to receive the signal (and yes, I did include the correct number of circular rings in the model, even though they'll never show up in glass).

An even cleverer way is to use two more reflectors to focus the waves to a point, which is what's done inside the Gregorian dome. The dome itself looks a lot like an icosphere, but unfortunately, it's subtly different. As you can see, I never figured out what the shape really is.

And that's about it for now. The model is with the etching company, but there's a bunch of stuff that could be done with this for education and outreach... even if my Half-Life 2 thing doesn't pan out. The telescope is a nice size - quite a bit bigger than the Colosseum and a heck of a lot bigger than any other (filled aperture) radio telescope. Size comparisons become a lot easier with a 3D model than trying to Photoshop everything, and are always a good way to impress people.

Right now, I'm working on a textured version for pretty renders. After that I'll make realtime version. Maybe we can have an online app where you can take a virtual tour of the site, and have all the moving parts in their correct, live positions. Or you could roam around the Observatory, looking for people causing RFI in the weirdest role-playing game ever :

You find someone talking on a mobile phone. Do you :
A) Ask them politely to stop.
B) Explain to them that we could detect their phone even if it was on Mars, so they're ruining someone's observations.
C) Tell them they're just a complete jerk.
D) Punch them in the face.

... or something like that. It may require a teensy-weensy bit of work to become the next Skyrim. Anyway, there's definitely tonnes of stuff to be done with this. Watch this space.

NESSIE FOUND !

In a stunning breakthrough, scientists have announced today that the Loch Ness Monster has been found. Astonishingly, this revelation came not from Scottish biologists, but from a Puerto Rican astronomy student.

...

I don't often talk about cutting-edge research, but this time I can't resist making an exception. My summer student is currently experiencing the joys of trawling through data cubes looking for the hydrogen gas which fills many galaxies. He found this one just a few days ago. And bugger me (no, not literally) if it doesn't look quite a lot like a famous Scottish lake monster.

The galaxy image shown above is the optical counterpart of the hydrogen he detected, and comes from the Sloan Digital Sky Survey (the plesiosaur is some random painting from the internet since there isn't a corresponding Digital Plesiosaur Sea Survey) . Here's the galaxy without a visit from Nessie. I did no image processing on this whatsoever - this is exactly the image taken straight from the survey data.

A head, neck, flipper, and perhaps even spilling water from its mouth -
sure seems like Nessie to me.

Galaxies do not normally look like this, of course. This is pretty dang weird. Not nearly as weird as Hanny's Voorwerp, but definitely very unusual. To try and figure out what was going on, I contacted my theoretician friend (who we last met destroying galaxies) to see what he could come up with. His considered professional opinion was that the galaxy looks more like a scorpion. Maybe he's right. I wasn't going to argue - he'd just destroyed an entire galaxy, after all.

I normally avoid posting such contemporary research here for several reasons. Firstly because I never really wanted this to become a science blog at all, but that's what happened (anyway there aren't enough science blogs insulting the Queen and photographing potatoes in my opinion, so maybe that's not such a bad thing). But more importantly - new results should never be trusted. Science is slow, and above all, full of doubt. Mistakes are made and all too often results which seem exciting one day can seem pretty humdrum after a month of painstaking data analysis finds a critical flaw. Or, to quote Terry Pratchett : "It wouldn't be research if you knew what you were doing."

In this case, though, there's no amount of work that can be done that will stop that galaxy from looking strange. In fact, it can be stated with absolute certainty that the galaxy has a weird-looking morphology, if we accept that "weird" means different from the norm. Some other tidbits about Space Nessie :

• About 700 million light years distant.
• Nessie measures about 200,000 light years across (roughly twice the size of the Milky Way).
• Contains around 10 billion times the mass of the Sun in hydrogen gas (this is quite a lot as galaxies go, but not really extreme).

So why does Space Nessie look so different to other galaxies ? Well, the honest truth is we just don't know what's going on here. It's probably the result of two or more galaxies colliding and merging, which is known to be able to produce really weird shapes. Maybe the "head" of Nessie is a smaller dwarf galaxy which is being ripped apart by a larger one, leaving behind a trail of stars to form the "neck". Maybe. It's going to take a lot of work to figure out exactly what's happening. Which is fun.


UPDATE : For those who like these things, this was reshared by Discovery News, CSIRO, The Sun (yes, right above the page 3 girls, pretty much) and... Fox News. Urrgh.

Postdoc Down

In the last three posts I've destroyed a galaxy, photographed a potato and turned an asteroid into 300,000 cruise ships. Well, gosh darn it, this time I'm going to write a proper blog post, without any CGI at all...  not much, anyway.

This week saw the departure of postdoc Julia Deneva, who I owe many times over for various beach and restaurant trips, to say nothing of the months of daily lifts to the Observatory every morning. Thanks Julia ! Except now we're short of one of our chief Dominion players and, more worryingly, that leaves me as the only Arecibo postdoc...

Julia appears to have been morbidly addicted to the telescope, having visited as an undergraduate, a graduate student for the single-dish summer school and as a pre-doctoral fellow for a whole year, then came back as a postdoc under Cornell and stayed on after the management change. Having climbed every single rung on the AO career ladder short of management, she's running away to sea. By which I mean the Naval Research Laboratory, which I choose to believe is a giant floating telescope that's bristling with cannons.

Imagine my disappointment. Julia's husband lives nearby though,
which is possibly more of a motivation to move than a sea-going
telescope.

Common Observatory practice appears to be to bestow departees with a large picture of themselves, standing in front of the telescope, signed by all the staff. I don't know why anyone would want such a thing, but Julia didn't get one of these. This is possibly for the best as she insists on closing her eyes every time she has her picture taken. Instead, Julia will eventually get a glass cube with a little model of the telescope laser-etched inside.

Julia leaves behind an unfortunately transient legacy of cats. These cats, except for one. Apparently they have "run amok" and must be removed.

Julia has also promised to take a cat, haven't you Julia ?

Fortunately the total of 5 cats are being steadily relocated. Three are still up for grabs. Want one ? Seriously, come along and take one - you catch it, you keep it. Actually, we'll catch them for you. And vaccinate and sterilize them too*. Take a cat and I personally will give you a tour of the telescope, probably. Heck, I'll even shower you with official CLAWS merchandise of your choice. Hats, mugs, stickers, badges, T-shirts... we haven't got any of them, but we'll order them specially.

* By which I mean take them to the vet. No-one here has the requisite scissor skills to properly snip that which must be snipped.

In non-Julia related news, outside of the world of cats and science lies the at least equally strange realm of Puerto Rico. It's full of cows...

... locals ...

... elaborate floats ...

... and suspect young ladies holding large feathery spears for some reason.

This was the sugar cane festival of Hatillo. It also featured some truly outstanding (not in a good way) karaoke but not much moonshine, which is surprising given that sugar cane is the main ingredient.

Finally, in totally unrelated news, my first media interview appears in this month's Ciel et Espace. French readers should go at once to the nearest newsagent and buy a copy. You'll find not only the galaxy size comparison charts in handy printed form, but also a 1 page interview in which I jabber on about the importance of outreach and Star Trek. Mexican readers won't have to wait long either - a special space edition of Conozca Más comes out... well, about now, actually.