Travelogue: Scotland

Eilean Donan Castle

Having never been to the UK before, I really wanted to see some parts of it that were a bit further afield. So it is important to grab opportunities to travel when they come. Last week, there was a mini nova conference near Manchester, just the local astronomers around the UK which they hold every 6 months or so, kind of informal but a good opportunity to see other astronomers who focus on novae and even some of my collaborators that I rarely see face to face. This was actually held on my birthday -- I made some comments to Benson about this, saying that the ONE DAY I knew I had to work ALL SUMMER without taking off was, of course, the day I'd most want to NOT work and take off and celebrate. So, anyway, the day prior, I rented a car, then woke up at 6:15am on my birthday to drive 3 hours to the conference (with Benson navigating/snoozing in the passenger seat -- he just worked in a nearby library the whole day while I was chatting with folk).

Benson and I at Jodrell Bank

All in all, it was a decent birthday (terrible traffic aside) - I had a lot of good conversations with people, talked about science, got some feedback on my research, and so on. But because we were already going up towards Manchester, Benson and I reasoned it was a good time to just keep going north. Which is why we rented the car for a full week and spent a long weekend in Scotland! So, after spending a chunk of Friday afternoon visiting a collaborator at the Jodrell Bank Observatory (the central hub for the radio telescope array eMERLIN, which is spread over the UK -- we got quite a nice tour of the facility, in fact) we drove up to Edinburgh. Our first night was a simple one -- we just checked into our hostel (which was made entirely of shipping containers and absurdly inexpensive), went into town and walked around old town. There, I lusted over the multitude of plaid clothing that was *everywhere* (if you ever look through my wardrobe, you may notice that I have a fondness for it), and, more importantly, went for dinner and drinks. Naturally, I had to have haggis for my first ever trip to Scotland... followed by four shots of whisky (divided by two, though, since Benson and I split them). You see, we deliberately went to a place called Whiski, which I would highly recommend, which has 300 different whiskies available for tasting. Which is a good selection, I think. We actually went back again on Monday night to get 3 more shots. Benson is a BIG whisky connoisseur, so I pretty much let him chose what we got. Between the 2 tastings, we got one whiskey from each of the regions -- Highlands, Lowlands, Islays, Speyside, Campbeltown, and the Islands, plus an extra Lowlands -- I don't quite recall what we got, honestly, you'd have to ask Benson -- but they were all very good. I tend to prefer whiskies that don't have an overly strong peat taste and that are smoother, but I'm also not that fussy or knowledgable about the whole thing. I know more now than I did at the beginning of the weekend though.

The next morning, we arose from our shipping containers,  bright and shiny early, and drove to the Isle of Skye. Which was a lovely drive across the lowlands and highlands, going through a national park at one point. Now, you'll note that I was driving. Benson hasn't really driven since he got his license 10 years ago, and doesn't really trust himself behind the wheel. Whereas, I actively enjoy driving (assuming no traffic). This was my first experience driving in Britain, however, and it took some getting used to not only DRIVING on the wrong side of the road (and through endless roundabouts), but also shifting gears with my left hand. Manual cars are the norm in the UK, and much cheaper to rent, you see. My dad taught me how to drive stick shift when I was in college -- he kept a manual car around in part for this purpose, and had me drive said car to my camp job over the summer every day, so I'd get used to it. So it's a useful skill! I never finished writing up my last summer's activities (whoops) but this came in handy last year when we were in Italy, as well -- we stayed at a friend of Benson's house, and borrowed his grandfathers car. Which was stick. And I was the only one of the four of us that could drive -- which made me the designated driver throughout the Italian countryside, and enabled us to see much more of it than we would have been able to otherwise. So worth holding back a bit more on those italian wines....

Anyway, the Isle of Skye was GORGEOUS. We did a lot of hiking over the weekend, drove all around the island, had lots of delicious fresh seafood (and were even taught how to shuck oysters by the proprietor of the wonderful Oyster Shed), saw a TON of sheep (sheep EVERYWHERE), visited the Portree harbor, and, naturally, toured the Talisker Whisky Distillery. Talisker is one of Benson's favorite whiskies, so we got to sample a few very nice ones, too. We stayed at a lovely little B&B which overlooked the Eilean Donan Castle in the town of Dornie (not on the Isle of Skye itself, but within driving distance). After we spent a very nice 2 days in Skye, we headed back to Edinburgh, to explore the town a bit more in depth. We still mainly wandered -- I bought myself some plaid items as souvenirs, we had more delicious food, more whisky at Whiski, visited the main castle there, and climbed up Arthur's seat for a gorgeous view of the city. All in all, a good trip! Now, we're back in Cambridge again, which means... we should probably start thinking about buying tickets and planning our trip to Greece for the last week of August. Yeah... things to get on soon...

The view from Arthur's Seat

Travelogue: Random Moments from Conference Week

Cheetah Encounter: Sunday afternoon, heading towards the harbor, I was walking with a few other people and we decided to take a bit of a shortcut, that they had taken earlier. It was early enough in the week that we didn't actually know the long way around, in fact - I was just following the crowd. But our way was blocked off, by, of all things, a Cheetah. Yes, there was a live cheetah blocking our path. Sitting on a table, on a leash, held by 2 handlers, looking quite bored, and possibly tranquilized somewhat. Apparently there was another conference going on, and they had a live cheetah as some sort of entertainment, and they were holding an event right in the hotel plaza where we wanted to cut. They eventually let us by, holding the cheetah back, but I got within about 2 meters of it. NOT what I expected to encounter in the Cape Town harbor...

Kicked out of the Aquarium: The conference reception was held Sunday evening at the aquarium in the harbor, and we had a great open view into the shark tank, and around the lobby. There was also a set of unlocked doors that led into the rest of the building. So I, and several other astronomers including my advisor, naturally wanted to explore the rest of the aquarium. And it was super cool - the lights were all dim, including in most of the tanks, and we could wander around the floor looking at giant crabs, jellyfish tanks, and so on. Until we were informed that no... we weren't actually supposed to be in there. Oops! Who knew a closed door meant "do not enter"?

Local Cuisine: There has been a surprising lack of distinct South African cuisine around here, though I've had a few things that are apparently local. The dried fish that I've mentioned, a couple desserts (a gingery pudding, brandy sticks), something called Bobotie, which is like a shepherd pie only with a egg custard top. Probably the most different thing I've tried, however, is a local meat that has popped up several places. It's generally not cooked in any particular style, but the meat itself is local: Springbok. I'd never HEARD of springbok, so naturally I ordered it at first opportunity. Its a (very cute) type of antelope, which are very common in the area. I haven't seen any live ones, but they're pretty tasty. The meat is a little tough, so they tend to be braised or roasted for long periods of time. Kind of like a tough venison, is the closest taste I can describe. Not bad, certainly worth a try. Hopefully I'll find some other local cuisine soon - there are some local curries, for example, which I've been wanting to try... but haven't found any place that serves them.

Robben Island

Robben Island: Of course, I had to go for a bit of the historical side of Cape Town and South Africa, definitely a region with a lot of it. Wednesday afternoon was given off to all of us, and we were given the option to take a tour of Robbin island, the prison island where Nelson Mandela (and other political prisoners) were incarcerated. This was a boat ride across the water to the island, followed by a bus tour around it: stopping at a scenic overlook where we had a great view of the city and Table Mountain, one of the prison yards, the quarry where people were doing their hard labor (as well as secretly teaching and talking with each other). And finally, one of the ex-prisoners there gave us a tour of the prison itself, pointing out Nelson Mandela's cell and the garden where he hid his writings, and telling us about details of prison life (for example, that your food rations depended on your skin color/ethnicity). Overall, a very interesting trip.

Countryside in the Winelands

Boschendal: For the conference dinner, we went out about an hour outside the city to the wine country, to the vineyard/restaurant Boschendal.  Beautiful countryside, lots of tasty food, and some VERY excellent sauvignon blanc  - I may have to buy some at some point before I leave, if I see it again. But most awesome of all - I hadn't actually thought much about what kind of sky I would see in the south as far as specifics go. I don't know the southern sky very well at all, in fact, so I just thought "oh, I'll learn some southern constellations" and didn't think much more about it. We'd been to tour the SAOO (South African Optical Observatory), but we had to leave before it got truly dark, and that was much closer to the city anyway. But when we went to Boschendal - that's over an hour outside Cape Town, so you could actually see some LOVELY night sky - the Milky Way, for one thing, which is a baseline for how good a sky you've got - if you can see that, it's got to be a pretty decent sky (at least, that is what I think, having lived in NYC and Baltimore). But I ALSO discovered how Large and Cloud-like the Large Magellanic Cloud actually IS. It hadn't crossed my mind, but of course, it IS in the southern sky, and it was known before there were actual telescopes, so it's quite visible by eye down here on a sufficiently dark night. It had to be pointed out to me, because it is very easily be mistaken for a cloud, but it was a little taller and at least 3 times as wide as the full moon would be (though happily it was a moonless night). It's undoubtedly even larger on a darker night, as it gets even more diffuse around the edges. Super cool. I also had some other constellations pointed out to me, most notably the southern cross. I commented it looked more like a small square than a cross (since I'm used to the northern one, which is quite a bit larger and has a central star which serves as a crossing point), but I can pick that one out now. The only constellation I could recognize myself was Orion, which was upside down to what I'm used to seeing! This weekend I'm going to be going on an after-conference tour to SALT (South African Large Telescope) in the Sutherlands, where I hope to see even more of the southern sky, maybe even the SMALL Magellanic Cloud. It will be a lot further from the city, so I have high hopes for a clear and dark night sky.

Actual Astronomy: Of course, I'm at this conference for a reason, not just to play tourist. It's the first all-novae conference in a decade - one of a series, this is the 4th such conference in ~40 years. I'm meeting scientists from around the world, all of whom work on the same type of object that I do. I'm introducing myself and my work to the community, meeting people who may become future collaborators, exchanging ideas, and absorbing all the science I can. And of course, it's my first international conference - I gave my first ever talk at a conference, on radio observations of the nova V1723 Aql, which seemed to go pretty well. I even got several compliments on it! Certainly an interesting topic (in my completely unbiased opinion!). This is an object which by all appearances, when it first went off in 2010, was a completely typical classical nova (at least in optical observations). In fact, the reason our group (see blog post "The Astronomer's Day On") started observing it was in the hopes of getting a good "baseline" for radio behavior. While the late time observations fit predictions pretty well, there was an early time 'bump' in the light curve (here this means the brightness of the nova over time, when observed in radio at various frequencies) which one can't explain at all with the simple model. So my talk described our speculation about the nature of the bump, in addition to the late time fitting to models which estimates the total ejecta mass and showing off our observations in general. Our radio group had quite a good showing at this meeting, and in fact I met people who I've been collaborating with but hadn't physically met before. In addition, I got to talk to many new people, from people whose papers I have read, to those working on topics I didn't know much about at all. About 90 people, from 22 countries, were in attendance; the various venues, activities, and schedules were all well organized; and the talks were by and large quite interesting - all in all, a very good conference!

Me, giving my talk (taken by Allen Shafter!)

Travelogue:Getting to Cape Town

So this week, I'm traveling to Cape Town, South Africa, for a conference on Novae (which, as you recall from blog post "The Astronomer's Day On," is my topic of study). The conference is from the 3rd-8th, and I'll be giving a short (15 minute) talk on 7th. After that, there is a two day "after conference" tour (optional, but fun), and then I'll be bouncing about on my own: mainly around Cape Town, but also in the town of Stellenborsch (in the wine country!).  I'll be flying back on the 18th, arriving in NYC on the 19th. Since I'm writing these on the road, these entries will probably be a little shorter, and possibly light on pictures, until I get back (sometimes I forget to take out the camera when I'm enjoying myself, or what I'm doing just isn't particularly scenic), not to mention more clearly written chunk by chunk.

The flight and layover:
I could love Munich for its airport alone. Seriously, great place to have a layover. Germany in general, probably, but this is the first time I've ever been in a German airport - the last time I was in Germany, I came by train, and the only other time was driving across the border of France to grab a meal, just so I could say I've been. There are little areas you can rent that are a quiet space to nap - an actual cot - plus a little desk to work at, if you want such a thing. But if you don't want to pay, there are chairs - both regular and lounge - and plenty of them, each with their own place to plug in your computer. So I can stretch out comfortably while waiting for my flight (as I'm doing as I type these vary words, though they'll be posted later, due to lack of internet connection). I suspect on my next layover I'll find one of these chairs and just NAP, since THAT layover is 4 hours, and early in the morning, rather than this one, which was 12 hours and starting at the beginning of the day I'm supposed to be getting used to. I think I recall I had the choice of  this or leaving super early in the morning, rather than in the late evening and sleeping on the plane, but honestly, I'm not really quite sure why I decided to book this flight in particular, when I was being reimbursed the cost.. But it was enough time to go into town. Which leads me to the German trains - so fast, efficient, and ON TIME. I traveled in Germany with Benson in 2011, for a bit, and they actually make an announcement and apologize for the inconvenience if the train is - LITERALLY - a minute late. And it's a rarity if it is late at all. I'd love to see the NYC metro do that...

Also, Germans do vending machines RIGHT

So I bought an all day train/bus pass at the airport, and went into Munich. Like I said, I've been here before, with Benson, so my first stop was actually the central station, where I knew I could pick up some VERY tasty sausage for cheap (breakfast!), plus then move on to anywhere else in the city easily from there. The second stop was a museum that we missed last time, the Deusch Museum, which was a museum of science and industry - very up my ally. Not the usual science museum, though - it seemed very focused on the instrumentation side of things, so there was a lot of really awesome old equipment from all branches of science. Astrolabes, old slide rules, tubes of all sorts, telecommunications, musical instruments, old cars and jets and helicoptors and rockets, whole ships, seriously, everything. It was a pretty cool museum, and a good chunk of the signs were translated into English, though not all. So that was a good place to spend my time. I also managed to hit not one, but 2 beer gardens. I'd been to both before, Augustiners for a light lunch (a bowl of liver dumpling soup, after the sausage, and a nice tall half liter of Augustiner Hells), and Hirschgartin for dinner (a half of a pork shank, with a potato dumpling and a pretzel, plus a nice tall half liter of a local Weissbeir.) Both were delicious, and refreshing. In fact, I wasn't able to finish my dinner, but got it wrapped up and through security with no problem, so I'll be having a some very tasty pork for breakfast tomorrow, as well! It was very easy to get through the airport, and security very efficient, so there was hardly any wait to get through again. Anyway, an enjoyable layover, for the most part! And now, an overnight flight (again) which will land me in Cape Town, where I've already booked a nice shuttle to take me directly to the hostel. Hopefully I won't be *too* tired, but I don't have anything planned for tomorrow (aside from working more on my talk!) just in case.

Addition:
Just jotting this down, I'm super exhausted and will be taking a nap shortly - but I've officially arrived in Cape Town, now and the hostel I'm staying at is really nice. I'm staying at a hostel for the first 2 nights before moving to the conference hotel (since while I'm getting free housing provided by the conference people, they're not going to pay for students to stay extra there, either). I'm in an all girls dorm room, which is nice, and it's very clean and seems pretty secure. Right near the waterfront area, so it looks like there are some nice places to walk around near by. But for now, after an 11.5 hour flight, I just got in, got a shower, checked e-mail and whatnot, and am going to take a NAP.  I can hold out until this evening or tomorrow to start exploring, and it would be nice to be well rested if I'm going to work on my talk any. Even if it is a lovely 92 degree (!) afternoon....

The Astronomer's Day On

Me on Mauna Kea (HI), during an observing run last August.
Those aren't the telescopes I was working with - the
SMA is an array of 8 radio dishes, whereas these are all
optical telescopes near the top of the mountain!

As I said in my introductory post, I am an Astronomy PhD student, studying at Columbia University. While the main focus of this blog is what I do when NOT at work, astronomy is a very important part of my life. Last week, I had a thesis committee review: every six months (or so), the panel that will eventually be deciding if I get a PhD meets, and I give an overview of what I've been doing, and what I plan to do. This is all designed to keep my thesis ON TRACK, make sure I'm not floundering, and to give me advice on what they think I need to work on, or keep doing right. So, having just ruminated on my research, where it's going, and what my accomplishments are to prepare for this meeting, it seemed an appropriate time to introduce readers of this blog to my research.

In a word, I study novae. Novae can occur in binary systems where a compact star (most often a white dwarf) accretes mass from its companion. When enough matter builds up on the surface of the star and some critical mass is reached, it triggers a thermonuclear reaction which blows off material from the white dwarf as a shell of plasma. This material is quite hot and luminous, so naturally at this point you will see the star brighten - hence the name, "nova", which means "new star." Depending on the type of nova, this material will brighten and fade on the order of days to weeks to a few months - in the OPTICAL range. However, my research focuses on the RADIO light curves of novae, and how they evolve over time. In the radio regime, the time it takes for the lightcurve to rise and fall is usually on the order of months to years.

A lot of my work is based on the fact that different frequencies of light travel through plasma differently (like X-rays travel through your hand, making it possible to image bones, but you can't see through your hand in visible light). Therefore, if you look at the plasma ejected from a nova in two different frequencies, you'll get two separate brightnesses. So you can watch a nova in multiple frequencies and watch how it changes in each one, put it all together, and using some simple models and assumptions, make estimates about various properties of the ejecta (and thus the star and explosion as well). One of the things I really like about novae is that they occur on a time scale that we can NOTICE and KEEP TRACK OF. A new nova can go off at any time, and people all converge on it at once. You can clearly see the time evolution of these objects, and have a list of novae which are doing interesting things.

 But... sometimes the models don't quite work. Our assumptions are too broad, or there is some extra factor we overlook, or we get an answer which flies in the face of current nova theory. One of these issues is going to be the basis of my thesis: we're finding too much mass. Based on standard nova theory, we can estimate how much mass should be ejected in a nova shell. But when we do our model fits with observations, we seem to get masses over an order of magnitude (ie 10x) greater than what we expect. So is the problem with theory, or with our model fit assumptions? We've been making more and more detailed observations of novae, and we're still getting these large masses, even when taking in some additional factors in our model fit - because you can only stretch parameters so far and still keep your assumptions reasonable.

One of the assumptions we generally make in our models of novae is that the material ejected is spherically symmetric. Now, we KNOW that isn't true - nova ejecta is known to have clumps, or jets, or other asymmetries - but its a useful first-order approximation to make. So I'm also interested in jets and outflows in general, and what they imply about the system. Jets appear on multiple size scales in the universe: they can appear in outflowing systems from white dwarves to active galactic nuclei. So, in addition to novae, I have interest in other systems with varying brightness due to accretion, with outflows - like cataclysmic variables in general (where variation is due to accretion between two stars), and symbiotic stars (white dwarf/red giant binary system). I also have a fondness for neutron stars, though I don't really study them specifically at the moment. So really, binaries, jets, and compact stars in general hold my interest!

Some of the VLA telescopes
(in it's SMALLEST configuration)

I'm working with a collaborative group (the e-Nova project) looking at a number of different novae in radio, optical, and X-ray. The majority of our observations come from the Karl G. Jansky Very Large Array near Socorro, New Mexico.  This is an array of 27 individual antenna, working together as one (very large) radio telescope. I've been out there three times; however, these have generally been to learn how to do radio data reduction and analysis, not for observations themselves. When you get time on the VLA, you can input your operating instructions in the online system, and the operators out in New Mexico take care of the observing for you. The only observing I've done personally has been one trip out to MDM at Kitt Peak, AZ, two years ago, and one trip last August to the Sub Milli-meter Array (SMA) on Mauna Kea, Hawaii. The first of those trips was with a class on observational astronomy, where students got sent to the telescope (of which Columbia owns a share) to get experience with optical observing. The second, however, was directly related to my research: in order to obtain time on the SMA, you are required to send out an observer for a week to assist the local operators. So, when we wanted time for high-frequency radio observations of a few young novae, I got tapped to go. It was a pretty awesome experience... though sitting for a control room over a long night actually gets rather dull after a while.

Anyway, my collaboration has recently submitted two papers on which I'm a co-author. They are still undergoing the referee process, so they're not "published" yet and will undoubtedly change a bit before final publication, but they've been listed on the Astro-ph archives. I'm 9th and 10th author on these - it's a large collaboration - so I didn't actually do much of the writing, my contributions were more on the data side, as well as in editing and general discussion. But if you are interested in a bit more technical detail about what I've been working on, you can find those papers here.