Sodankylä Geophysical Observatory

EISCAT Measurement Campaign 2006

Last update: 2015-8-28, 11:28:45 UTC.

2006-12-01: Ilkka and Timo left Kilpisjärvi in the morning and Tero left SGO just before lunch to meet them in Kittilä, where he passed a harddisk with all EISCAT measurements to them and where he received the photometer system to be installed at Pittiövaara.

The installation of the photometer and the arrival of Timo and Ilkka in Oulu conclude this year's measurement campaign.

To be continued some day in 2007...

2006-11-30: Timo and Ilkka arrived from Svalbard in Tromsø in the afternoon and drove to Kilpisjärvi in order to spend the night at the optical station. At the same time, Tero, Antti, and Thomas used the good weather in Sodankylä to put the OmniPAL system back into place.

Results: OmniPAL (back at SGO)

2006-11-29: Temperature 0.2°C, cloudy, frosty, dry. We brought the second van to the Nordlysobservatoriet and gave the keys to Björn, who kindly agreed to pass them on to Timo and Ilkka when they come from Svalbard tomorrow. Then we left for Kilpisjärvi, where we loaded the OmniPAL system and continued to Sodankylä on partly very icy roads.

Markku, Juha, and Mikko continued to run a few test measurements on the UHF radar in order to compensate for yesterdays technical troubles. They collected about 2 hrs and 10 min of data before leaving for Sodankylä, where they arrived late in the night.

Results: OmniPAL

2006-11-28: Temperature +3.3°C, cloudy, raining, very wet, grey, miserable... Tromsø!

Radars: Since tonight's experiment is cancelled, we ran both the UHF and the VHF during Antti's ANTII experiment. The VHF alternated between arc-dlayer-ht and sippiD12. The UHF ran sippi4 for the first heating cycle (40 min) and thereafter tau2pl for the next 40 min.

We ran into difficulties running both radars and had to abandon the idea. This is a pity, esp. given that we saw PMWE again! After the ANTII experiment, EISCAT ran the Cluster support experiment, for which the VHF antenna needed to be turned to low elevation, which took some 15 to 20 min. During this time, the Inverse Team managed to do some more tests with the UHF experiment and collected about 15 min of data.

In the late afternoon we went to celebrate the end of the campaign in the Blå Rock bar in Tromsø with garlicy burgers and beer. We were joined by "local scientists" Tom Grydeland and Brön Gustavson. In the evening we packed all optical equipment, which had been inside all day to get dry.

Results: OmniPAL

2006-11-27: Totally cloudy and raining, very wet, grey and miserable. Proper Tromsø weather that is.

In the morning we ran ANTII again, i.e. Heater and VHF. The heater used 40-min cycles and we alternated the radar experiments arc-dlayer-ht and sippiD12 between these cycles. Again, we saw PMWE nicely.

CANCELLATION: We cancelled the UHF experiment "Aurora" for tomorrow night, i.e. 2006-11-28, 1830 UTC to 2006-11-29, 0130 UTC.

UHF: In the evening we were greeted with near complete silence in the control room. Apparently a power cut killed the system, not even the trust UTC-clock above the racks showed anything. It took about 45 min to find the problem (some breakers would keep flying) and trace it to "Junni," whose power supply seems to have broken and which developed an internal short circuit. Finally, at 19:08 UTC we started sippi4. At 20:10 UTC we will switch to manda and point the radar towards Kilpisjärvi. Clear over there, raining and low clouds here.

Results: OmniPAL, 2006-11-27_arcd_60@vhf.png, 2006-11-27_arcd_60_detail@vhf.png, 2006-11-27_manda_60@uhf.png

2006-11-26: Totally cloudy since midnight, temperature +3.4C, very wet, grey and miserable.

Optical: we have been very lucky so far, every night was largely clear and on most nights we saw aurorae. Last night even Kilpisjärvi was clear at times. The optical instruments have been mostly running fine apart from some small problems detailed earlier. We recorded beautiful auroral displays with all instruments, and the radar has so far been good to us if we exclude last nights problem of total loss of control of the UHF for half an hour (more than an hour at Sodankylä). A big Kiitos! to Markku Postila, whom we had to wake up in the middle of the night, and who promptly went to the radar site to fix the situation for us.

Radars: We ran tau8 on the VHF all night. There was a series of crowbars and at times we ran very carefully at very low power (360 kW). Finally we decided to restart the transmitter, which helped to some extent, and we were able to crank up the power to 750 kW. There were a few more crowbars in the night, but it went much smoother.

The UHF ran a variety of the special "sippi" experiments for the Inverse Team all night from 1830 UTC to 0130 UTC.

The connection to the OmniPAL was restored by rebooting the machine at ... Apparently there was a power cut in Kilpisjärvi, which messed up the local network.

Results: OmniPAL, 2006-11-26_tau8_60@vhf.png

2006-11-25: A few clouds, beautiful morning, -6C.

The first good news of the day: Antti analysed yesterday's OmniPAL data and found the Heater signal in it. Oh yeah!

ESR: After some small logistic problem, the daytime experiments starts on time at 0911 UTC. At 1600 UT we started the Poleward experiment.

Tromsø: no experiments during daytime. At 1600 UTC we started the Poleward experiment using tau8 on the VHF. Some weak auroral activity persists all the time, arcs were visible immidiately once it was dark enough. At 1830 UTC the Inverse Team started their special "sippi5" experiment on the UHF. This experiment ran until 2030 UTC. Thereafter we switched back to manda including also the remote sites.

We experienced two technical problems with the manda experiment. First the Eros command window simply disappeared as a consequence of a simple window resizing operation! We had to restart the experiment in order to be able to restart Eros. Then later on, at 2215 UTC, the terminal on Culdera froze completely and we lost all sites and data recording. We had to log in from another machine, and kill all relevant processes, then log out and back in to get it back. This took about half an hour. After that we managed to start the experiment at Tromsø and Kiruna, but not at Sodankylä, where the ACU had crashed and we had to ask Markku Postila to drive out to the site and sort it out for us. Since about 2320 UTC everything is good again. We learnt that Sodankylä had dropped out already earlier, at 21xx UTC.

To make matters worse, there seems to be a network problem in Kilpisjärvi: we lost the network access to the OmniPAL computer. We will try to reboot it tomorrow when Kari is awake. Since we won't run Heating before Monday, this is not that urgent.

Activity: we saw auroral displays all evening at Tromsø. Also Kilpisjärvi was clear until about 2230 UTC when clouds came in.

Results: OmniPAL, 2006-11-25_tau8_60@vhf.png

2006-11-24: Clear morning, cold at -12C.

At 0830 UTC our ANTII experiment started. The experiment used both the Heater and the VHF radar (boresight). On the VHF we alternated between two experiments: We started with 40 min of arc_dlayer_ht and then switched to sippiD12. After 40 min we switched back. We kept switching until the end of the experiment at 1230 UTC. The Heater modulations are summarised in the table below.

Start Stop Modulation
0830 0849 6s O mode, 6s off, 6s X mode, 6s off
0851 0903 20s X mode, 160s off (4 times)
0914 0929 20s X mode, 160s off (5 times)
0930 0946 6s O mode, 6s off, 6s X mode, 6s off
0950 1010 6s O mode, 6s off, 6s X mode, 6s off
1010 1030 300s O mode, 300s off, 300s X mode, 300s off
1030 1050 6s O mode, 6s off, 6s X mode, 6s off
1050 1110 300s O mode, 300s off, 300s X mode, 300s off
1110 1130 6s O mode, 6s off, 6s X mode, 6s off
1130 1150 300s O mode, 300s off, 300s X mode, 300s off
1150 1210 6s O mode, 6s off, 6s X mode, 6s off
1210 1230 300s O mode, 300s off, 300s X mode, 300s off

EISCAT: At 1600 UTC the first run of the "Poleward" experiment began. The experiment has the VHF at low elevation (30°) northward and uses tau8. At 1845 UTC the first "Aurora" exeriment started using manda. The remotes point to the E-layer peak, which is mostly between 100 km and 110 km altitude. The experiment is shared with the UK until 2330 UTC, and with Japan from 2330 UTC to 0140 UTC. This later part uses arc1 with cp1 geometry, but a common volume at 250 km altitude in the beginning and at 120 km later on. The Inverse Team listens in on both experiments.

At the EISCAT site the sky's been clear all day, but at about 2130 UTC clouds came in. The forecast is partly cloudy for the rest of the night, which isn't all that bad. Kari reports Kilpisjärvi to be cloudy, even though the clouds seemed to become thinner it started to snow later on.

Some auroral activity was going on all evening, SGO saw 200 nT fullscale, which is little compared to yesterday's event. The radar saw an E layer all the time, but practically no F layer. The E layer was on the weak side, it was hard for UHF Sodankylä to get a decent signal.

Results: ANTII, OmniPAL, 2006-11-24_arcd_60@vhf.png, 2006-11-24_tau8_60@vhf.png

2006-11-23: Tromsø partly cloudy, around freezing.

ANTII started at 0830 UTC using the Heater and the UHF including the remote sites. From 0830 UTC to 1030 UTC the Heater is modulated by 30-sec sweeps from 200 Hz to 6200 Hz, X mode, in support of the DEMETER pass at about 0933 UTC. The UHF uses the tau2pl experiment with antenna geometry of CP1. Jyrki reports that he can see the sweeps at Kannuslehto VLF station. From 1030 UTC to 1235 UTC the Heater will go into an X-mode beam-swinging experiment: from 30° S to 30° N in steps of 10°, 5 min at each step, modulation throughout 1 sec on, 1 sec off. Note that this experiment is 5 min longer than scheduled due to the duration of the heating cycles.

The VLF station saw the sweeps nicely. Please look at the result plot. The scale is unreadable in the picture, but it is a plot from 09:53:20 to 09:54:20 UTC showing frequencies between 0.2 and 7 kHz. Jyrki points out that the signal just below 2 kHz is much weaker than at other frequencies, which is due to Earth-ionosphere wave-guide attenuation. It is interesting that this can be seen already at a distance of roughly 350 km.

Schedule update: there was a mistake in the Finnish Operations Schedule. It wrongly indicated that the ANTII experiment is scheduled for Sat and Sun, but in fact it is not. The updated schedule is on-line for download from the main campaign page now.

The optical instrumentation (Meridian Scanning Photometer (MSP), Real Speed Camera (RSC) with video recorder and Digital Camera (DC) with control PC) was installed successfully during the evening by the Optical Team (Kari, Tero, Carl-Fredrik).

The MSP looks to about 182° and it scans from 70° to 85° across the field line. The measurement program starts at 1430 UTC and continues until 0500 UTC. The problem, which was found during last year's campaign, occurred again with the 630.0-nm channel, which is not in use because it causes malfunction in the other four channels. Everything worked during test runs and calibration in Oulu before the campaign, but not any more in Tromsø. The only change was the cable connection box which was taken from Sodankylä. Unfortunately the spare, used in calibration, is in Oulu. The timing of the PC is based on GPS.

The RSC looks along the field line and the signal is recorded to 4-hour video tapes at single speed. The recording starts daily around 1500 UTC and continues until 0300 UTC. The video timer is set manually.

The DC s pointed field aligned, too. The control PC runs XP, but we cannot get the computer connected to the net. The PC's time is set manually. The picture grabbing starts around 1530 UTC. Because the lens cannot be focussed to infinity at full aperture, we need to use it at a smaller aperture setting. We have used 5-sec exposure time with 5-sec delay between the pictures. The camera is connected via USB cable and there is a USB extender using an RJ-45 cable. Sometimes, when the grabbing program is stopped, it has looses the drivers for the camera.

In the evening very nice auroral display, starting almost immediately after dark and continuing all night. SGO recorded 600 nT fullscale.

Results: OmniPAL, VLF total power

2006-11-22: Grey morning, +2C. We heard from the UK Team that they do not want to run their HIPI experiment on Thursday (2006-11-23; they have highest priority). Thus we will run the ANTII experiment and use it for DEMETER/VLF support. We will use the tristatic UHF radar instead of the VHF radar!

Oulu and SGO Teams are on their way to Tromsø. They will turn the OmniPAL antenna in Kilpisjärvi by 90°, because it was found yesterday that we installed it in the wrong orientation. Updated info: bearing OmniPAL-Heater 315°, distance 90.4 km; bearing OmniPAL-JXN 232°, distance 436 km.

VLF station observed a new phenomenon (again!): boomerang-shaped hooks in the spectrum, which can be seen only in the purely right-hand circular power. The duration of these events can exceed 200 sec. Time of the plot: 1200-1300 UTC, freq. 0-9 kHz.

All teams arrived safely in Tromsø, Kari arrived in Kilpisjärvi and will spend the night there. Finally some activity. Bz turned southward and we even saw some aurora here at the EISCAT site. The Sodankylä magnetometer registered a substorm of 300 nT.

Results: OmniPAL, VLF circularly polarised power

2006-11-21: It's a grey Tromsø day today, temperature -2.4C. Rumours go that there are some staff problems at the ESR and also the UHF developed some technical issues, presumably as a consequence of being forced to look at absolutely nothing all night long. Let's hope everything's in order when our radar campaign starts. News: In the evening, the UHF worked ok.

The VLF station reports that they had some troubles with the cabling of one aerial. Also one of the aerials needs to be turned by 7° in order for both aerials to be orthogonal. Jyrki sent a plot of total power, which shows quasi-periodic emissions (Pc3-modulated). It spans the time from 1300 to 1330 UTC, and the frequency axis is from 0.2 to 3.2 kHz. The horizontal lines are PLHRs of which we can now see many more due to the much more sensitive, new receiver.

Results: OmniPAL, VLF total power

2006-11-20: Fantastic winter morning, -11.7C, clear skies and a blue-red sky. Activity last night: very, very quiet: Kp was zero for the past five 3-hour periods. The evening began with some stars visible, but then clouds came in.

Results: OmniPAL

2006-11-19: OmniPAL seems to work fine. Frequencies are set to those specified by Mark on 13th Nov. System rebooted at 18:05 UTC. Kari is on the way to Oulu. Beautiful starry night at EISCAT site, very clear, temperature -8C. Geomagnetic activity: very, very quiet.

Results: OmniPAL

2006-11-18: Kari installing optical equipment in Kilpis. Thomas installs the OmniPAL Rx. The antenna is aligned to point at 315°, i.e. NW towards the EISCAT site. The bearing to JXN is 232°, which is 83° off and therefore the aerial has hopefully very low sensitivity to the very strong signal from JXN. For testing, we run the OmniPAL with the same frequency settings as in Pittiövaara. Operations start at 14:37 UTC.

Results: OmniPAL

2006-11-17: A group of 11 people went to Kannuslehto and set up the VLF station. The first broad-band (up to 40 kHz) recordings were successful. Antti and Thomas went to Pittiövaara and packed up the OmniPAL receiver. Kari Kaila is on the way to Karesuvanto and Kilpisjärvi.

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Last modified: 2015-08-28, 11:28:45.