Wednesday, 22 February 2017

Life on Svalbard, Mid February 2017

Fully settled into Svalbard, university studies and exploring the settlement is well underway. With the Sun still below the horizon throughout the day, my brain is getting used to going about daily activities in the dark. However, each day, there is a blue glow on the horizon, reminding us that the sun is getting closer and closer each day. One thing I am not getting used to is the snow storms! The wind is strong, the snow is endless, and white outs are frequent, with more snowfall in an hour than UK probably has had in the last ten years *Laughter*. Unlike the UK however, life does indeed go on, whatever the weather!!
Blue Glow on the horizon

In between lectures at UNIS, I have been exploring the town further. The town itself is small and quaint, currently covered in snow, giving it the full Arctic look! There is one supermarket, Svalbardbutikken, a few restaurants, and a small handful of shops, including a fur shop which has a taxidermy polar bear and bison inside! A small group of us then went to the beach. Not a white sandy, clear blue sea kind of beach, a rocky, snowy, arcticy looking beach! It was peaceful and undisturbed, allowing us to take in the surrounding snowy mountains. We continued on to the edge of the ‘Safe Zone’, where one of the famous polar bear signs lives. The sign warns people of the risk of polar bears on the island, and going past this sign without a gun can be dangerous. So, we took a few pictures with the sign, and oh so wildly, poked our toes across the border of the safe zone before heading back into the town and bypassing the northernmost church.

After weeks of extremely cold weather (-20˚C), the Arctic suddenly warmed up, and for almost a week, temperatures were above 0˚C. Not good. These temperatures are normally only seen during the summer season. As a result, a large portion of the snow melted, and we ourselves, after adjusting to such cold temperatures, also melted. Climate change, or just a blip?

To brighten up the week, a few reindeer came to visit, and were grazing on the exposed ground outside the brakkes. The reindeer in Svalbard are much different to those on mainland, much smaller (and cuter), with a white thick coat, and they are the northernmost living herbivore mammal. Here, they are not confined to any space, and roam the island freely, so it is extremely nice to look out of the window and see these beautiful animals.

The warm weather then came to an end, and snow began to fall, covering the entire island once again. With this, we decided to take a walk up to Gruve 2. Gruve 2, translated, mine 2, is an old coal mine that operated during the 90s. The walk up to the mine is steep and slippery, without spikes at this point, there were times when it was just easier to crawl up, through the deep snow. The mine was opened in the 1920s, and then was partly bombed during the war. Following the war, the mining industry boomed in Svalbard and mine 2 was operating once again. Now, only one mine is still in operation on Svalbard, mine 7. On our way back down, we could not stop slipping over, and so in the end, we all slid down the mountain on our bums, and found this was the quickest most efficient way to get down any mountain covered in snow, but definitely not the warmest!

That is all for now,
Stay tuned for the next installment and check out the video of these adventures linked below!

Ser deg seinare!

Sunday, 19 February 2017

EISCAT Svalbard Radar

This week, I was lucky enough to work at the EISCAT Svalbard Radar, where I was able to run experiments and also be involved with designing and running a new experiment. EISCAT runs incoherent scatter radars north of the Arctic circle in three countries (Finland, Norway and Sweden). The radars take measurements of the terrestrial ionosphere and atmosphere. One of these radars is located on Svalbard, around 15 km from the main town, Longyearbyen. The EISCAT Svalbard Radar (ESR) operates at 500MHz, and consists of two dishes; a 42m field aligned antenna, and a 32m moveable antenna. 

On our first evening at ESR, we were given the task of making our own antenna using tin can, thus, making ‘cantennas’. The first step was to choose the perfect can for our cantenna. The tin cans are short circular waveguides that can be used as antennas that will work at certain frequency ranges. Our desired frequency range was 2.4-2.48GHz, and so using this and measuring the diameters of the tin cans, we could then calculate the cutoff frequencies for each can and determine which one would work for our frequency range. The ‘fruit cocktail’ tin can was chosen to be made into an antenna. Once we had the right sized can, we then had to determine the location of the feed into the waveguide, and the length of the monopole. The monopole is a single wire and is feed directly into the waveguide (the tin can). The length of the monopole needs to be a quarter of the wavelength in free air. We marked this length on the wire, and cut the wire to a cm more than the desired length to allow for fine tuning the wire later. The monopole then needs to be fed into the can at a specific distance from the back wall of the can. This distance is a quarter of the wavelength inside the waveguide. After many calculations we made markings on the can of the centre of the back wall, and of where the monopole would be fed in. Holes were drilled into these two locations such that the monopole was fed into the can, and the can could be screwed to a plank ready for testing at a later date.

On the second evening, my group (myself, Brad and Magnus) ran our own experiment on the ESR. The klystrons are turned on in the transmitter room where the power that’s transmitted is generated (typically MWatts of power). The power is then released in bursts, ‘pulses’ into the sky, alternatively between the 32m and the 42m. Our experiment was designed in order to look for polar cap patches; localized density enhancements in the ionosphere that enter that polar cap at the dayside cusp and convect into the nightside, exiting the polar cap near midnight. Signatures of polar cap patches can mainly be seen in the electron density and ion drift velocity measured by ESR. In addition to ESR, we would be using SuperDARN and DSCOVR data to observe the convection speeds and the IMF-Bz respectively. The 42m dish is fixed and points field aligned (184.5˚, 81.6˚), whilst we set the 32m dish to perform an azimuthal scan. The azimuthal scan scanned to the North East of Svalbard from 0-120˚ azimuth at an elevation of 30˚.

To operate the ESR, a tool called EROS (command line based) is used to start, run and stop experiments, as well as starting and stopping recording of data and changing the position of the antenna. The real-time performance of the radar is monitored using the program RTG which shows various parameters such as the raw data dump, time and elevation/azimuth. A tool called TRIL is then used to monitor interlocks and transmitter status. TRIL is used to put the klystrons in four different modes; in black heat mode the klystrons are powered up so that they are ready for transmit. Just before transmitting, Standby mode is used such that the klystrons are ready to transmit within a couple of seconds. In Transmit mode the power is transferred through the waveguides and to the antenna. The Off mode is then used when the radar is being switched off for a long time.  The experiment can then be started in the EROS command window by specifying the location of the experiment elan files, the time start of the experiment, the scan file for the dishes and the ID of the country running the experiment. Once the experiment is running, the real time data can be observed by loading the RTG plots, and analysed using Guisdap. The RTG plots show the pulses of the 32m and 42m. Plots of the raw electron density, electron temperature, ion temperature, ion velocity and radar parameters are then loaded in Guisdap. During our experiment, there was very little ionosphere and so no polar caps were observed. However, we learned valuable skills in operating and running ESR, reading and analysing real time raw data. This data will be further analysed, alongside other data obtained from ESR in Matlab at a later date.

On the third evening at ESR, we continued with our cantenna designs, and designed a new experiment for the ESR. With the cantenna, we fine tuned the monopole; this involved cutting small amounts off the monopole and until it was transmitting at an optimum. We then worked together to design an experiment such that the ESR 32m dish scanned the same area of the ionosphere as SuperDARN. SuperDARN is a high frequency coherent scatter radar, and there is more than 30 of these radars in both the northern and southern hemisphere. One of these is located on Svalbard, and is a new radar beginning operations in October 2016. With numerous calculations and discussions, and experiment was ready to be tested the following day.

On the fourth evening, we were set to test our new experiment. The 32m dish was set to perform an azimuthal scan from 231.24-179.4˚ at a 150˚ elevation. SuperDARN always has 16 beams in a scan, each with a 3.24˚ separation, so in order to match the scan as closely as possible to ESR, an 8 second dwell was required for each beam. With both ESR and SuperDARN set up, the new experiment begun. It was shortly found that the 32m period had been set incorrectly, this was quickly altered and attempts were made to re-sync ESR with SuperDARN. This was unsuccessful, and so the experiment had to be re started. On restarting however, the experiment was doing exactly what we had desired it to and numerous structures were observed for further analysis.

Our final evening at ESR, we put our cantennas to the test. We set up two of the best cantennas to transmit our desired frequency, and then a signal is received. We had many people running to and from the cantennas, drove a car to and from then cantenna, and even attempted to interpret a plasma bubble. The spectrum of moving bodies can then be seen on via a programme on the computer. Then, after a long week of no aurora, we finally got some beautiful aurora which looked stunning as it danced above the two antennas. A wonderful end to a wonderful week!!

Testing the Cantennas

Aurora over 42m dish

Aurora over 32m dish

Between my last blog and this blog, I have done lots of different things in and around Longyearbyen, so stay tuned for the next blog and video coming very soon, ‘Life on Svalbard’!! Hope you enjoy the video that accompanies this blog too. 

Ser deg seinare!

Sunday, 5 February 2017

The Kjell Henriksen Observatory

This week we spent four evenings from around 5pm until 2am at the Kjell Henriksen Observatory (KHO) as part of our fieldwork for the Upper Polar Atmosphere. The KHO is located about 15km from Longyearbyen with a number of optical and radio instrumentation used to research the middle and upper atmosphere. The first auroral station was built in 1983 at the old airport runway in Adventdalen with the help of Kjell Henriksen. The current observatory was then built in 2007 in order to host more instrumentation and observe in a less light polluted area. The observatory was named the Kjell Henriksen Observatory after the late professor Kjell Henriksen in honor of his dedication work he had done for the previous auroral station.  At the KHO, there are 30 instrument rooms with domes of diameter 1m, which are used by the majority of the instruments to observe the the atmosphere above us.
One of the domes on top of the KHO, 31.01.17. Photo credit; KHO 

Of the large range of optical and radio instrumentation at KHO, we specifically learnt about the various All-Sky Cameras and Imagers, the Meridian Scanning Photometer (MSP), and various spectrometers. Additionally, we worked directly with the MSP and 3 of the spectrometers, performing absolute calibration on each of these instruments. In addition to the data obtained from the instruments at KHO, data from SuperDARN, EISCAT, DSCOVR and the Norwegian line of magnetometers was also learnt about and used in various activities such as auroral predictions.

Our first evening at the KHO involved three activities. Firstly, we were taught about how the MSP is set up and collects data. This involved a rotating mirror, which is positioned under a slit in the building, as opposed to a dome. The mirror then reflects the light that comes through the slit from aurora into the MSP. The MSP is then composed of four filter tilter units and photomultiplier tubes. The filters are layers of thin film which only let in a certain wavelength. For the MSP, four filter channels observe the four main auroral lines; 6300Å (red), 4278Å (blue), 5577Å (green) and 8446Å (near IR). This allows intensity measurements of each wavelength separately. We then calibrated the MSP, which is done by turning off the mirror and facing it towards south (pointing up towards the slit, reflecting into the MSP), using software which performs tilt calibration. From the result, the peak and background measurements are selected on specially designed softward and inputed into a computer code. 

Following calibrating the MSP, we were then taught about the various All-Sky cameras, what they consist of, how they work, and what we can observe with them. Using data from DSCOVR and SuperDARN, we then learnt how to make auroral predictions, which turned out to be pretty accurate. In the very late evening we saw some of the best aurora I have seen so far, the sky filled with green and red dancing lights. Still the most beautifully incredible thing I have had the privilege of observing.

On our second day, we practiced calibrating the MSP again, which went well. This was then followed by eating lots of pizza – a very important part of the evening for us hard working physicists. We then went on to learn about some of the spectrometers in operation at the KHO, how they work and how we can use the data we obtain to investigate the atmosphere and the aurora. More auroral predictions were made, and once again delivered.

On our third night, we performed absolute calibration of the three of the spectrometers; 1 m 'Silver' Ebert-Fastie Spectrometer, 1 m 'Green' Ebert-Fastie Spectrometer and 1/2 m 'Black' Ebert-Fastie Spectrometer. The absolute calibration required two groups. One group would be in charge of fitting the lambert screen to the mount and then positioning the mounted lambert screen accurately over the spectrometer domes, two of which were located on top of the KHO, the third on the end side of the KHO. The second group would then be on the roof of the hut, approximately 49m from the main observatory building. On top of the hut, a tungsten lamp was mounted, and the distance from the lamp to the lambert screen was found using a laser. The calibration then included 10 minutes of measurements with the tungsten lamp on, and 10 minutes of it off for the background measurements. 

On our fourth and final night, we performed absolute calibration on the MSP. This is all done from within the instrument room, where there is an LED lamp and a lambert screen inside a box that is beneath the instrument. The measurements are taken when the mirror is facing downwards between 268-272˚. Following this, we were then taught about the magnetometers, and used real time data to calculate the height and the intensity of a current in the atmosphere. There was some aurora this night too, however it was not as intense as the first two nights, and we remained indoors and watched it via one of the All-Sky Cameras.

During our time at KHO, all the instruments were constantly recording data, of which we will be using to write a report on a certain auroral topic. Working at the KHO was a great experience, and I loved working hands on with instrumentation, and seeing the instrumentation obtain first hand data of what we were currently observing, I felt like a proper physicist (which I am ofc!)!! Thank you to the KHO for having us!! 

Ser deg seinare!

Wednesday, 1 February 2017

Settling into Svalbard

This next installment of my blog is about the following few weeks after the safety week, settling into Svalbard, and seeing some incredible aurora.

Following the safety week, those of us from Aberystwyth University still had two exams to sit; Electromagnetic Theory, and Quantum Technology, and so we could not spend too much time relaxing, and instead had to cram on as much revision as we could. In addition to our revision, our lectures started on the Monday. Already enjoying learning about the aurora, and the atmosphere in which we live, and super excited to work hands on with the instruments that they have here in Svalbard.
Walking home one evening, I experienced my first snowstorm. Unlike the UK, when there is lots of snow here, and snowstorms etc, everyone just keeps going! The snowstorm started off really fun, there was snow going everywhere! However, as we were walking up the long road to Nybyen, along side a giant mountain, it suddenly got very intense. Here, I experience my first 'White out', where the snow was suddenly blowing around me everywhere to the extent you can see nothing by white, you cannot even see your hands in front of you. For wee English Jen, I got pretty panicked! After just learning about avalanches, and knowing I was right next to a giant snow covered mountain, I had visions of my life ending in a pile of snow! Silly me, this snowstorm is normal (apparently). After finally arriving home, my whole outer was frozen! Snow and Ice was everywhere, and had even managed to get inside my scarf, inside my coats, just everywhere! The first exam we sat was on the Wednesday. We do not talk of this exam anymore, and that tells you everything you need to know. Awful.

The weekend however brought some faith back to our run down mindsets, and Svalbard blessed us with some absolutely beautiful aurora, that lit up the skies. I was mesmerised by the colours, the structures, the movement, dancing across the sky above me. The aurora is one of the main things I am going to be studying here in Svalbard, which as we have learnt, has more than one kind of aurora. Typically most people are aware and see the nightime aurora. However Svalbard is one of the few places in which we can also observe the daytime aurora. Both aurora have many differences, including where the particles come from, and the types of emission that dominate.

Aurora in Nybyen, Svalbard

After a weekend of aurora and revision, Monday was time for our second and last exam (for now anyway). To our surprise, the exam went amazingly well, we all came out feeling optimistic and ready to celebrate! As we had finished our exams, and it was Chris’ birthday, we went to Svalbar to have food and drinks. Svalbar is one of the most popular restaurant and bar in Svalbard, especially for the students at UNIS, thanks to the famous Svalbar burger. Quite possibly the best burger I have ever tasted. To top off our day and evening, on leaving Svalbar to walk home, we were again greeted with beautiful dancing lights in the sky.

When we got home, I got my camera out and attempted a time lapse. Now as my DSLR has no automatic setting for this, and I have no remote to attach to do it for me, I sat patiently in the snow, continuously pressing the button to take photos. I managed to get about 200 photos in 20 minutes on 5 second exposure before my freezing cold fingers were yelling at me to go inside! Much to my dismay, I had not noticed that the camera was out of focus the whole time!! But, the aurora was so big and bright, this wasn’t overly problematic, and with the help of Brad, I managed to get a nice little time lapse video of the aurora (See in Video at the end!). I will keep trying for better ones though! It is definitely getting super cold though, my eyelashes keep freezing whenever im outside for more than 5 minutes!!
UNIS in the Polar Night

After weeks of complete darkness, the sun is slowly getting closer to the horizon. The sun is due to rise over the horizon on 15th February, however Longyearbyen will not have the sun shine onto it until around 8th March, due to the surrounding mountains. Nevertheless, we are entering what they call the blue period! Which is super pretty! Either side of midday, the town is illuminated by a beautiful light blue, which is slowly getting lighter, and lasting longer and longer each day. For the first time at the weekend, we were able to see so much more of the beautiful scenery that surrounds us. Stunning snowy mountains, glittery waters and a very Christmassy looking town as we walk down from Nybyen. Safe to say I’m very excited to see the sun soon, it definitely starts to feel quite weird living in darkness 24 hours of the day. One downside to this however is, once the sun first comes out, the days get longer and longer very fast. The day length gets longer by approximately half an hour each day. The 14th February is the last day that the sun is down all day, come the 19th April, the sun will be up all day until late August.
UNIS in the blue period

Next blog entry will be all about the Kjell Henriksen Observatory, and the amazing things we get to do there!

Ser deg seinare!