This is the final update because we launched at 730 UT on January 18, 2008 (I will explain what UT means below).
It was extremely exciting time. Early in the day, we could see that conditions in the solar wind looked very promising. On the other hand, the skies overhead were completely clouded over and we would not be able to see the aurora that we wanted to fly over. To make things worse, the moon was about half full, which is too bright for the most sensitive cameras that we had been using to image the aurora, so even if the skies cleared we would not have images. Fortunately, we had discussed this issue with some researchers from China the day before. They have been operating similar equipment about 100 km north of here (Ny Alesund). They agreed to send us their images and we managed to make the connection fairly early on the 18th. With their help, we were able to see that the skies just to the north of us were filled with the type of aurora we were waiting for.
This aurora appeared around 0600 UT, but we could not yet see any hint of it with our radar. Again, from what we were seeing in the solar wind, we had reason to think that it would move towards us. In the meantime, the skies over our station were clearing and the Norwegians had managed to set up an backup camera that would not be damaged by moonlight. A bit after 0700 UT, the aurora drifted toward us as we had hoped and we could see it both in the Chinese camera from north of us, as well as with our local camera. Once we were sure that our sky was filled with this aurora, we called for the launch to go ahead, but were told that we would have to wait for some Norwegian fishing boats to move away from the "impact area" of the second stage of the rocket. This took some time, since they had to pull their nets in, but they did move away from the danger area. We were very grateful for their cooperation and returned the favor with a fantastic show!!
I will try to get a picture of the aurora that was overhead when we launched. There is also a movie of the aurora overhead during this same time, taken by Prof. Fred Sigernes (UNIS), using a tracker camera. The movie starts out cloudy and you can see the clouds moving very fast. The aurora, on the other hand, do not move across the image.
This was a very high altitude rocket. The picture below shows the path of the rocket on a Google Earth picture. There are two white lines. The line to the left was the "nominal" trajectory; the line to the right shows the actual trajectory. The island in the center of the picture, where the rocket flew over, is where we have been sitting. The big white patch on the left is Greenland. The total flight time of the rocket was about 25 minutes. All of our instruments worked and we now have lots of work to study to analyze the data!!
Here is a picture of the launch, borrowed from the Andoya Rocket Range website (there are other photos there, too). Remember, the rocket was launched from the north coast of Norway, very far from where we were sitting.
There is a funny side to this story. Just a few hours after we launched, we started hearing that some of the Norwegian newspapers were reporting sightings of a huge meteorite. And then, there were reports of a UFO
sighting. Sorry, both of these (and many other) articles are in Norwegian, but you can see the mistake!!!
About UT: "UT" stands for Universal Time. When people talk about what time it is in New Hampshire, they are talking about the time in Eastern Standard Time (EST). Times around the world are different. Here in Norway, I am writing this at 4:04 in the afternoon, which is 10:04 in the morning for people in EST (a 6 hour difference). You can imagine that trying to coordinate all sorts of activity around the world and, especially a rocket or satellite that is traveling across many time zones quickly, can be very confusing if we have to say "EST", and so on. For this reason, we do everything in UT, which is the same regardless of where in the world you are. So, when we tell people anywhere that we launched at 0730 UT, they know what it means and don't have to add or subtract hours to figure it out.
One final point. This launch has been an excellent example of international cooperation, with contributions from the US, our colleagues in Norway, a Swedish team who shared radar time and provided some other ground-based measurements, a team from the United Kingdom who also provided radar and optical measurements, a Japanese group who helped interpret the radar data to help us decide when to launch and a Chinese group who provided auroral images at the most critical time. In addition, we found afterwards that a Japanese satellite flew over the same aurora and that they specifically made measurements to support this mission.
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