Starception

The interesting thing about the Universe is that it’s big. Really big. With enough space and time, even the rarest events can find time to happen, with bizarre and unusual things happening as a result. And some rather good evidence for one such unusual thing was found earlier this year.

I like explosions...

A Thorne-Żytkow object is a bizarre and seemingly paradoxical kind of star. Named after the two astrophysicists who first hypothesised its existence, Kip Thorne and Anna Żytkow, a strange star like one of these is a hybrid, of sorts. It’s believed to be a red giant star with a neutron star hiding at its core.

Earlier this year, the star HV 2112 was found to behave… not quite as expected. It didn’t quite match with models made to predict its behaviour, suggesting that there was something odd about it. While the astronomers involved stress that their idea is a cautious one, a possible explanation is that this star is precisely one of these curious stellar cocktails.

Red giants are astonishingly large. A typical sized red giant star could engulf our entire inner solar system without much difficulty. The largest known star, VY Canis Majoris, is a red giant – and it’s large enough to be difficult to fully appreciate. The human brain wasn’t engineered to encompass the immense scales which we encounter in astronomy. Neutron stars, on the other hand, are stellar corpses. The still-hot cinders from once mighty stars long ago burned out. Neutron stars are quite mindbending little things in their own right. The core of a massive star, containing more material than the Sun, compressed down to the size of a large city here on Earth, neutron stars are so unimaginably dense that their gravity can bend light and warp the fabric of spacetime.

So if you have a densely populated region of space, such as a globular cluster, there are enough stars in such a tight space, that every so often, a couple of them may crash into each other. If the two stars colliding with each other happen to be a neutron star and a red giant, the end result is a Thorne-Żytkow object. After colliding, the neutron star spirals inwards, sinking to the core of the ill-fated red giant. Once there, it proceeds to violently consume the larger star. As material from the red giant crashes onto the surface of the neutron star, it makes things incredibly hot. Hotter than the cores of most normal stars. Huge gravitational forces compress and heat up anything which lands on the neutron star, eventually mashing together individual atoms and driving nuclear fusion at hugely accelerated rates. Unusual chemical isotopes may form, driven by the high temperatures, and this bizarre type of fusion.

Stars like these may at first appear to us as red supergiants, or possibly as more violent Wolf-Rayet stars. Eventually though, one of two things will happen. The most extreme outcome is if the neutron star can accrete enough mass to collapse into a black hole. If this happens, the energy released will result in a supernova, blowing away any outer layers of stellar material not yet accreted. Otherwise, the two will eventually merge into a single object, resulting in one massive neutron star. Leftover stellar material will most likely end up as a massive accretion disk surrounding the neutron star. Interestingly enough, this disk works in the same way as the disks around young stars. It may even be massive enough to form additional companion stars of its own…

Whether or not HV 2112 is actually one of these objects remains to be confirmed. But it’ll be very interesting if it is. I haven’t read the actual study yet, but it’s available on arXiv if you’re curious.

Image credit:
European Space Agency and Justyn R. Maund (University of Cambridge)

You just won’t believe how vastly, hugely, mindbogglingly big it is. I mean, you may think it’s a long way down the road to the chemist’s, but that’s just peanuts to space…

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良い月曜日を

In other news, here is a selfie taken by a robot on the surface of another planet.

I hope you’re having a nice Monday!

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Rules to Live By

I found this on tumblr a few days ago, and really liked it. 11 rules of a scientist’s life. I liked it because it does a good job of summarising the rules which I genuinely try to live by. As Carl Sagan once said, “Science is a way of thinking much more than it is a body of knowledge.”

They're pretty good rules for anyone, really...

In fact, I liked it so much, that I wrote out the 11 rules on the first page of my new notebook. Taking care to think in the right way is probably the biggest difference between being a scientist and simply working in science. While I understand that not everyone may share my opinion, I consider this more than simply a job. To me, it’s a lifestyle. I like to try and apply this way of thinking to the rest of my life too. Granted, I may not always succeed; I am, after all, only human.

The source for this list is benchfly, where you can also find a pdf download if you feel like printing it out for whatever reason.

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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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