Typical KAIRA

Today's photo has a bit of everything. The LOFAR HBA tiles, the LBA array in the background, Saana dominating the horizon, the storage containers and site area, and our trusty observatory vehicle.

The KAIRA site (Photo: D. McKay-Bukowski)

Valhalla

Always curious to try local produce, I tried this herb liqueur by Koskenkorva. It comes in a matt black bottle, rates at 35% and is ominously titled:  "Valhalla".

Herb ingredients are: Angelica achangelica, Artemisia absinthium, Achillea millefoium, and Glycyrrhiza glabra. 

Roadworks

Driving back late one night from KAIRA to SGO there was (yet another) hold up. This time roadworks. In fact there is a bridge under repair on the route from Kittila to Sodankylä and this is where we got stuck.

We were the only car.

And yet the delay was... well...

Plasma lines at Arecibo

25 MHz wide plasma line profile at Arecibo, 2.5 seconds of integration. 

A while ago, Thomas covered the Arecibo radar school (you can see our black rack receiver on the table in one his pictures). During the school, a little bit of data taking took place. Between his lectures, Phil Erickson ran data collection with our 25 MHz digital receiver, in anticipation for a longer campaign that will occur later this year. As I wasn't in Puerto Rico, and I've been traveling elsewhere, I'm only now starting to analyze the results. But they are quite nice.  The system can pretty much do what the existing 5 MHz wide Pentek system can do, but at 25 MHz bandwidth, allowing us to measure plasma line profiles such as this. You'll probably need to zoom in the picture to pick out the narrow plasma line. There is also a higher resolution version on line here.

Anyway, this is quite a successful first try. The IF will need to be at a different frequency than 260 (e.g., 264 would be nice), as plasma line below 10 MHz folds, and can also be seen "sliding" down from +12.5 MHz too. Another option is to bring a tuner to shift the band to a lower IF. Also, the wide band IF doesn't seem to be wide enough. The upshifted line isn't that visible due to filter roll-off. 

Data extraction

There are numerous computers in the RF-container, which handle data processing, control and storage. One of these has now been taken out and has been moved back to SGO for use there in some of our interferometric riometry development work. During the extraction of this data system, we had the side cover of the RF-container signal processing racks off, thus once can see the other computers, network gear, etc.

KAIRA data systems (Photo: D. McKay-Bukowski)

Missing in action

Today's photograph shows the frameset of HBA tile #75. Or, we should say... the former HBA tile #75. It is missing due to a severe blizzard that swept through the site at the beginning of the year. We are still waiting for a quote from ASTRON to get this replaced.

Frameset for HBA tile #75 (D. McKay-Bukowski)

A big blade

heading back from KAIRA to SGO the other morning, I was held up for a considerable period of time at the turn to Meltaus. The reason for this was that a convoy was moving three huge blades of a wind turbine and the first of these was starting to make the turn just as I arrived at that point.

It was quite a long wait as the turn was very difficult given the huge length of the blades. I tried to estimate the length and I suspect they are 40-50 metres long each.

Turning wind turbine blades. (Photo: D. McKay-Bukowski)

Information about the project can be found here: http://www.laatumaa.fi/tuulivoima/joukhaisselka-sodankyla/

Arctic green

At this time of year, the Kilpisjärvi region is pretty green. Most of the snow has melted and the trees are not quite yet changing to brown for the autumnal drop. Today's photograph was taken looking south along the western bank of the mound on which the antennas are located. The mountain on the left edge is Saana and on the right is Pikku Malla.

Looking south from KAIRA (Photo: D. McKay-Bukowski)

LBA aerials

KAIRA has 48 low-band antenna (LBA) aerials. These were designed by ASTRON (the Netherlands Foundation for Radio Astronomy). The arrangement of the aerials looks pretty random, but in actual fact it has been carefully chosen to give a good beam-pattern for the radio telescope. Each aerial comprises a steel grid which acts as a ground plane for the aerial. The post is PVC (starting to fade in places due to UV-light exposure) and the black cap at the top contains the low-noise amplifiers (LNAs) - one for each polarisation.

The wires that extend from the cap to the corners of the ground planes are the antenna wires. The form crossed inverted-V dipoles, giving good all-sky sensitivity. Actually the wire part only goes about halfway down. The lower part is either nylon line or elastic, which is used to hold the aerial in place.

Low-Band Antenna (LBA) at KAIRA. (Photo: D. McKay-Bukowski)

Ounas River

Today's photograph is dawn, seen over the Ounas River, not far from Kittila.

Ounas River, Lapland, Finland.

Mushroom harvest

Some of our readers may recall the great mushroom picking expedition of 2013. Well, this year, our Supreme Mushroom Leader (Lassi Roininen) set forth again on another epic journey (this time without lackeys to make a mess of things) and, once more, came back with a lovely mushroom harvest.

Mushrooms from the forest.

Of course, our regular readers will know the fate of any food produce brought to the EISCAT building at Tähtelä on a Sunday afternoon... home-made pizza!

Pizza done!

Not surprisingly, everyone was happy to have a piece or two. And, you must admit, mushrooms are rarely cooked fresher than this!

Nom. nom. nom.

KAIRA site buildings

I took this photograph during a recent trip to KAIRA. The structure on the left if the RF-container. note the large grey panel on the near-side... that is the cowling to protect the airconditioner from snow and ice. The timber structure on the right is the HBA cable mausoleum. This is where additional cable delay line length is placed. Normally on LOFAR systems, this is underground. However at KAIRA both the LBA and HBA arrays have above-ground housing for the extra delay lengths. The other raised building is the site office (known locally as the "barracks").

RF-container and HBA mausoleum, and then the site office. (Photo: D. McKay-Bukowski)

An unexpected guest

The other day there was something banging and clattering outside my room. I couldn't figure out what was going on and I didn't spy anything directly outside the window. Then, there was a strange snorting noise. Really weird.

Anyway, curiosity got the better of me and I got up to go and have a look.

Easily startled... but hopefully not back in greater numbers. (Photo: D. McKay-Bukowski)

Don't stare at me like that! (Photo: D. McKay-Bukowski)

LOFAR Aerial Photos – Nançay

Another of the LOFAR sites has become visible in aerial imagery. The French site at Nançay can now be seen in Apple's Maps.app, which is supplied with iPhones and iPads. If you want to find it yourself, here are the co-ordinates: 47°22.54'N, 2°11.56'E, or go to Nançay and look for the large T-shaped antenna array north of the town. Under the left "arm" of the T, you'll find the LOFAR site.

Photo: Apple Maps.app.

Sunlight on the EISCAT dish

Arriving back late at the observatory one evening I caught the late evening sun striking the 32m EISCAT dish. The photo doesn't really do it justice, but the colours and lighting were sublime.

The Sodankylä 32m EISCAT dish (Photo: D. McKay-Bukowski)

Supermoon

Currently, there's talk in the media again about the so-called "Supermoon." What is it? The Moon's orbit around the Earth is not circular, it is elliptic, and the orbit's closest point, the perigee, to Earth is about 50.000 km closer than the farthest point, the apogee. Every so often, full moon on Earth coincides with the time the Moon is at its perigee, and therefore it appears to be unusually large. When this happens, it is called "Supermoon."

The full moon of 10th August 2014 was a Supermoon, and so was 13th July 2014 /(photo above). Also the next full moon will be a Supermoon on 8th September 2014. After that it happens again in August, September, and October 2015.

See also: on spaceweather.com, there's a side-by-side comparison of the size of the moon as seen from Earth in March and August 2014.

Photo: Thomas Ulich.

Reindeer antler

In the KAIRA site office we have a strange "trophy" on the wall.  This is a reindeer antler. Reindeer lose their antlers naturally and if you wander through the Finnish wilderness, you will occasionally find one. We found this one near the KAIRA site and now it is mounted on the wall.

The KAIRA reindeer antler (Photo: D. McKay-Bukowski)

Moody KAIRA

Arrived at KAIRA pretty late last night. It was a moody scene. Low cloud lurking over Pikku Malla and everywhere damp and foggy.

Low cloud over KAIRA (Photo: D. McKay-Bukowski)

KAIRA Lemmings

Lemmings are very common in the Kilpisjärvi area, and they have featured on this blog before. But when we went for a service trip to KAIRA in late June, we took a simple panorama with an iPhone, and then transformed it into a circular, so-called "little planet" panorama – and we were quite surprised by what we found!

Click on the image for higher resolution; you can just make out the KAIRA site in the 4 o'clock and 8 o'clock sectors!

With this image we wish all of you a very good weekend!

Photo and processing: Thomas Ulich (on MiVyoo you'll find the original panorama and details on how it was done).

Little KAIRA Planet

Recently, we wrote about how to generate a panorama from 360 images of one degree field of view. However, we can play this game some more. These panoramas are 360°, which means that their outer (left and right) edges match exactly. Therefore, one can use an image manipulation program such as Gimp to create what is knows as "little planet" images. The name stems from the fact that these landscape panoramas are fully encircled by sky and thus look a bit like a planet, alas in the wrong scale.

Here's the little-planet version of the sunny KAIRA panorama, which in addition was rotated in order to have Saana at the top like in the image above. The star-shaped shades are due to the automatic exposure of the GoPro time-lapse camera.

The key ingredient to making these kind of images is Gimp's distortion filter "polar co-ordinates."

Photos and editing: Thomas Ulich.

A related and more explicit description is available on the MiVyoo blog.

KAIRA Egg-Timer Panoramas

Previously, we wrote about a 360° panoramic time-lapse film we made using an egg timer. For the photo above, we wanted to combine all 360 images (one per degree of roation) into one large panorama. This meant to cut from every photo a tiny narrow centre slice and to combine these into one large image. If you look carefully, you can make out the stripes.

On the next day, the weather was much nicer, and we repeated the egg-timer photography. However, due to the GoPro fully automatic exposure settings, and the variable lighting due to fast moving clouds and the bright Sun, it was not possible to make a nice pan-lapse out of these photos, and as you can see, the stripiness is much more pronounced in this image, even though the blue sky is very nice of course.

You can click on the above images to get larger versions.

Original photos and panoramas: Thomas Ulich.

A related article was published on the MiVyoo blog.

KAIRA Pan-Lapse Film

In late June, we visited the KAIRA site in Kilpisjärvi on a maintenance trip. One of many tasks was to repair an HBA cell, which got damaged in a severe storm in spring. Another task was to take lots of high-quality photos of KAIRA and its surroundings for various documentation and illustration purposes.

Right on the first evening, we put a tripod bridging the gap between tiles H57 and H47 on which we mounted a wide-angle GoPro camera, which was glued onto a very cheap and simple egg timer. The egg timer rotates 360° in one hour, and the camera was set to take a photo every 10 seconds, thus taking 360 images, one per degree of rotation.

The full 360° panorama can be assembled by sticking together twelve images, which are five minutes apart. The only problem is to find out how many pixel the image rotates in five minutes, which is 30° of rotation.

The photo above shows such a montage (click to enlarge), featuring the famous mountain of Saana in the sixth pane from the left. Since we have a full rotation, one photo per degree, we can assemble such a panoramic view in 360 different directions, each one showing the a full 360° panorama. Then, we combined them into a short film, giving the impression of full-panorama rotation.

The above explains how we did it, but one can understand what's going on also this way. We generate a time-lapse film from all the images, showing a slow rotation. Then we cut out the centre vertical section equivalent of 30° rotation from this film. Thereafter we glue twelve copies of the very same film side-by-side, but advance the film for each step just the right amount, so that it fits to the previous copy of the film.

We hope you enjoy the result.

We got the idea for these pan-lapse films from Ken Murphy of Murphlab, please visit his site for this and other exciting time-lapse projects.

Photos & pan-lapse: Thomas Ulich.

PS1: You might wonder why we didn't choose a nicer day with more blue sky for this experiment. In fact we did, but due to the GoPro's automatic exposure settings, the large contrasts between looking into the Sun and away from the Sun, paired with shadows of clouds moving across the sky, make the different panes/frames look very different and the result is much less pleasing. So grey skies are good for something!

PS2: Another somewhat more explicit blog post about this went out today on the MiVyoo blog.