Ring Ring

Asteroids are just boring hunks of space rock, right? Well, you might have thought so. But you would be wrong. Well… Mostly wrong. Some of them are rather interesting.

This particular interesting hunk of space rock is 10199 Chariklo, and it’s an asteroid with a ring system! Chariklo is a Centaur – that is, an asteroid which dwells amid the orbits of the gas giants. This one has an orbit which is very close to the orbit of Uranus. It has a diameter of roughly 232 km, it’s listed as a “possible dwarf planet”, and it may have water ice on its surface.

charliko

The ring system is a surprise though. It was discovered just a few days ago, as the asteroid passed in front of background stars. As stars are covered and uncovered by a planetary ring system, their light dims briefly as they’re occulted by the dusty material which makes up the ring. As all four of our solar system’s gas giants have rings of their own, this is a pretty well known technique. Saturn’s faint outer rings have been observed this way before. But finding two rings – named Oiapoque and Chuí for two of Brazil’s most well known rivers – orbiting an asteroid? Actually, that raises a few interesting questions.

There’s a lot about planetary rings which we’re not really certain about. How exactly do they form? How long do they last? What kinds of ring systems are possible? From our solar system, we can assume that they must form quite readily around gas giants, and we’ve detected a vast ring system around one exoplanet. Apparently, size is not a prerequisite though. If tiny Chariklo can hold on to a ring system, then it’s likely that any of the objects in the solar system could.

Suddenly, those pretty images of what Earth’s scenery might look like if our planet had rings don’t seem quite so far fetched. Then again, for all we know, maybe Earth did once have rings – at least, before they formed into the Moon.

Image credit: Lucie Maquet

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❝ I know nothing with any certainty, but the sight of the stars makes me dream.❞

Vincent Van Gogh

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The easiest person to fool

Sometimes I find something in my data which agrees with my predictions. This makes me happy, and usually prompts me to casually mention this fact on twitter. And sometimes, as in this case, my followers give me good advice.

Valid point.

@TWeDK raises a very interesting point. It’s interesting, because the human brain is very good at recognising patterns and looking for things. It’s also very good at seeing things which aren’t necessarily there. It’s easy to “see” what you were expecting to see, but that doesn’t mean it’s real. Even so, the statistic that over 1 in 3 people will believe that scientists doctor their results this way is something of a smack in the face.

In 1974, Richard Feynman gave an address at Caltech on the topic of “cargo cult science”. This delightfully coined phrase describes a practice which superficially appears scientific, but is not. Actual scientific research requires integrity and earnestness. Any scientist may make hypotheses, have expectations, and know what they’re hoping to find. After all, they are human. But a good scientist will also rigorously check over their own results to ensure that what they’re looking at is real. We can’t afford to become too attached to our ideas while we’re constantly hitting them with hammers to see if they break.

A cargo cult scientist, on the other hand, will seem to be doing everything correctly, but they’ll actually be somehow missing the point. To quote from Feynman’s address:

“We’ve learned from experience that the truth will come out. Other experimenters will repeat your experiment and find out whether you were wrong or right. Nature’s phenomena will agree or they’ll disagree with your theory. And, although you may gain some temporary fame and excitement, you will not gain a good reputation as a scientist if you haven’t tried to be very careful in this kind of work. And it’s this type of integrity, this kind of care not to fool yourself, that is missing to a large extent in much of the research in cargo cult science.

The first principle is that you must not fool yourself–and you are the easiest person to fool. So you have to be very careful about that. After you’ve not fooled yourself, it’s easy not to fool other scientists. You just have to be honest in a conventional way after that.”

I like to believe that I’m a good scientist. Perhaps driven by an innate fear of being wrong and/or looking foolish, I always check things multiple times. While it is easy to fool yourself and get excited over a result, you need to make sure it is what you think it is. I’ll even confess that I have indeed fooled myself a couple of times. Then I checked over the data again. At that point, I usually discover that what I thought I was looking at before was nothing more than a quirk in the way I was analysing things.

But this does highlight a rather important fact – As Feynman was lamenting, these vitally important things which we all should do are not, in fact, taught to us at any point. As PhD students, we learn how to do science by doing science. While a lot of graduate schools may be awfully keen to get us to take classes in how to talk to the press and how to design a conference poster (both very useful courses to take, incidentally), there are usually no courses at all about how scientific method works. We have to learn these things for ourselves. Assuming we care enough to do so. It seems logical that a lot of people probably miss out on a lot of important facts. Facts which, let’s be honest, are well known and should be taught to PhD students more formally.

I feel this requires more thought and discussion than I can spare the concentration for right now. When my work schedule calms down a bit, I should probably write more on this…

Actual proof that I sometimes do work.

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がんばれ

Let’s be honest. Learning Japanese is difficult. Especially being as English is my mother tongue. However, I remember saying back in July that I’d try to write a bit about life as a researcher in Japan. I don’t seem to have made good on my word just yet so, with apologies for the delay, I’m going to talk about the single most difficult part – learning to speak the language.

Frankly, Japan has been lovely and welcoming for me as a foreign researcher. My work colleagues have all been friendly and helpful, and I’ve managed to get all of my essentials have been taken care of with minimal difficulty (albeit with a few bureaucratic hoops to jump through). Thankfully though, I have a couple of Japanese friends who’ve helped me with a couple of those things. In particular, getting my mobile phone contract taken care of without help would have been… problematic. While I have, of course, been making every effort to learn Japanese, it’s still not an easy endeavour. And yes, it can be a trifle intimidating.

When I say I'm making every effort, I'm really not kidding.

Speaking English as your first language gives you a number of hurdles to overcome when trying to learn any non-European language. Japanese uses a different writing system and completely different grammar. Couple that with the fact that a fair number of words in Japanese are impossible to properly translate into English, and you have a lot to cope with all at once. In effect, the method which I used to use for speaking French – think in English and then translate in real time – simply doesn’t work here. Japanese is too different. Attempting to do this is why a lot of my conversations have resulted in head scratching, awkward pauses, and fragmented sentences. No, I’ve come to realise that the only way I’m ever going to speak Japanese properly is to train myself to think in Japanese.

This too is no easy feat. With the career I have, I’m lucky enough to be friends with people from a wealth of different cultural backgrounds. Between them, all the people on my Facebook friend list speak 35 different languages. As a result, I’ve spoken to a lot of people about languages. Most of them have told me the same thing – they usually think in their first language, and it took them a long time to learn how to think in another. I should probably find this slightly off-putting, but thankfully I can be quite tenacious when I want to be.

So while it may seem a fairly lofty goal to try and attain, I’m keeping sanguine for now. With a combination of learning how to break apart the language’s grammar, I’m gradually improving. Also, practicing with children’s books seemed like rather a good idea. Actually, in the 4 months I’ve been here, I’ve improved a great deal already. So let’s see what I can manage…

kodomonohon

頑張ります!

Yes, I counted. I was curious. And purely FYI, the 5 most common non-English languages among people I know are currently Spanish, German, Chinese, French and Japanese, in that order.

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Bohemian Gravity

This video made me giggle with glee! If you’re a fan of string theory and classic rock (and let’s face it, who isn’t?) then you’ll probably find this as wonderfully geeky as I do. A cut-down explanation of string theory and why it works, sung acapella to the tune of Bohemian Rhapsody. Things like this are why I love the internet.

The heads up for this came from one particularly awesome tumblr friend of mine. Because she’s brilliant. Thanks, you!

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Gamma Romance

On Valentine’s day in 2000, the x-ray afterglow of a gamma ray burst was detected in a distant galaxy. While its galaxy of origin was never properly identified, it’s still one of the most amusing Valentine’s day publications out there. A transcript of the full discovery message (citable as Antonelli et al, 2000) is as follows:

TITLE: GCN GRB OBSERVATION REPORT
NUMBER: 561
SUBJECT: GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
DATE: 00/02/16 23:26:36 GMT
FROM: Angelo Antonelli at Obs. Astro. di Roma <angelo@quasar.mporzio.astro.it>

L.A. Antonelli, Osservatorio Astronomico di Roma, Rome; [et al]

"GRB 000214 ``Valentine's Day Burst'' was observed with the Narrow Field Instruments (NFI) on board BeppoSAX from Feb. 14.5479 to 15.0793 UT (starting about 12 hrs after the burst trigger time). In the 2-10 keV image of all data from both MECS units 2 and 3, a fading point source (1SAX J185427-6627.5) is detected within the WFC error box (Paolino et al., GCN #557 and #559). The source position is R.A. = 18h54m27.0s, Decl. = -66d27'30" (Eq. 2000) with 50" error radius. In the first 20,000 s the source had a 2-10 keV flux of 5E-13 erg/cmE2/s and faded by a factor of two in the last 20,000 s. We conclude that 1SAX J185427-6627.5 is the X-ray afterglow of GRB 000214."

This message may be cited.

After all, what could be more romantic than giving the gift of a massive stellar explosion? Not much, if you ask me!

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Make a wish.

♥︎

♥︎

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#AcademicValentines

Us academic types just love to procrastinate, which is probably why there are so many of us to be found on twitter. This means that occasionally, twitter can be a geeky comedy goldmine. The latest source of 140 character hilarity? #AcademicValentines.

These are a few of my favourites. I literally laughed out loud at a few of these. Let the interdisciplinary nerd lulz commence!

Love knows no limits. Unlike research budgets.

Now that is smooth.

If anyone ever says this to you, it can only be true love.

Now that’s just totally adorable.

Easy, tiger!

 D’awwww…

Wow, that one actually makes me slightly flustered…

Bah. If you really loved someone, you would be their second author.

You know, this line might actually work on me…

I didn’t even realise you could find citations for those!

In the immortal words of George Takei – Oh myyyyy…

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❝ The more we learn about the world, and the deeper our learning, the more conscious, specific, and articulate will be our knowledge of what we do not know, our knowledge of our ignorance. For this, indeed, is the main source of our ignorance — the fact that our knowledge can be only finite, while our ignorance must necessarily be infinite.❞

Karl Popper

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Stellar Relic

The Universe is old. 13.798 billion years old, to be precise (give or take about 37 million years or so). That’s so old, it’s genuinely a little tricky to wrap your head around – 200 million years ago, dinosaurs roamed planet Earth. 580 million years ago, complex life emerged on our world. The earliest known evidence for life on Earth dates back to 3.7 billion years ago, a few hundred million years after the planet formed around 4.54 billion years ago. This, in turn, was shortly after the Sun itself formed, 4.57 billion years ago. But compared to some stars out there, the Sun itself is still young…

SMSS-J031300.36-670839.3

The unassuming little point of light in the centre of this image is something really quite special. Just 6000 light years away, it’s the oldest star ever discovered. Going by the designation of SMSS J031300.36-670839.3, this star is older than the very galaxy which we live in, and formed when the Universe itself was still young.

I’m not going to give an actual age for the star because, the thing is, we simply don’t know. Quoting Anna Frebel, a Stellar Archaeologist (which has to be one of the coolest job titles ever) – we don’t actually know the star’s age… quoting any age is pretty much made up. So how do we know this star is so old? Well, the thing about astronomy is that all we ever really have to go on are photons, but photons can tell us an awful lot…

ancient-spectrum

This is a spectrum of this star (corrected to give a flat baseline). Spectra like this can show you an awful lot about a star – and in this case, it tells me that this star contains a lot of hydrogen and not a lot else. Those lines are absorptions, coming from different elements which make up the star – the more elements, the more lines. Stars like the Sun are full of all sorts of interesting chemical elements. Astronomers call anything heavier than helium a “metal”, and a star like the Sun, with all of its metals is said to have a “high metallicity”. This spectrum, however, shows a very different creature. There’s barely anything there. Stars like these are termed “metal-poor”.

The thing is, in the billions of years the Universe has been around, stars have been industriously forming heavy elements from hydrogen. Inside the Sun right now, even as you’re reading this, 9 x 10³⁷ nuclear reactions are happening every single second. That’s ninety billion billion billion billion reactions. All of those nuclear reactions convert 620 million metric tons of hydrogen into heavier atomic nuclei. Every second! And right now, there are 300 billion stars in our galaxy doing exactly the same thing. When stars die, they cast all of those metals they’ve created out into interstellar space. Metals are everywhere, and any new star which forms takes in whatever elements are in the clouds it forms from. To find a star which is so devoid of metals, it would need to have formed from clouds which were similarly barren. In other words, it must be old. Very old.

In fact, the venerable SMSS J031300.36-670839.3 shows all the hallmarks of being one of the second generation of stars ever formed. The first ever stars formed quite soon after the Universe was born. They were composed of little more than hydrogen and helium. As a result, they were massive, fast burning, and rapidly died as supernovae. Known as “Population III” stars, these mysterious primordial stellar beasts have never actually been observed. However, we know they must have existed. All of those metals must have come from somewhere.

Immediately after these first stars died and exploded, they seeded the surrounding primordial gas clouds with the very first metals. Those clouds then began to collapse into the second generation of stars. Careful examination of the star you see above shows that it is indeed one of this second stellar generation – incorporating material from the first stars the Universe ever saw. And it’s one of no more than a small handful of such stars which are still burning. One of the last survivors of a bygone age of the Universe.

As with so much in science, these were named in the wrong order and the names have stuck. Calling them population I stars would be less confusing, but trying to change established nomenclatures is a little bit like trying to stop a runaway freight train.

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