The countdown is running

Hej everyone!

We had a first launch attempt on Tuesday, but the countdown was interrupted due to a problem in the Service Module. Right now the countdown is running for the second time, and so far everything looks fine! If you would like to see the launch check out the livestream on, and we are also posting live updates from the science centre on our facebook page

The launch is scheduled for 12:00 CEST (UTC+2), so don’t miss it!

Below is a photo of this morning’s rollout to the launch pad.


Final tests!

Good morning!

After few days of intensive working, fixing some bugs and problems that we discover, and preparing the experiment, we are ready!


Status white board of REXUS15 rocket

However that doesn’t mean that now we are free :(. Today we have the whole day full of flight tests, cold and hot (without and with firing pyro-cutters). Moreover, today is the last time when we can access inside our experiment since all the payloads of the rocket will be assembled today!!!

Finally, now we are finishing some testing before the hot count down that will be in few minutes. Then, if everything was fine for all the teams, we will say bye to our experiment until it is recovered after the launching. But don’t panic, we will be in contact with it through the communication systems 😉

Vi ses!

We launch on the 27th !!!

Good day rocket enthusiasts*,

A new version of the launch campaign plan has been announced yesterday and our rocket, REXUS 15, has the earliest hot countdown opportunity on Tuesday the 27th. It all depends mainly on the weather and payload readiness but chances are pretty high things will go as planned! A communication test between our rocket module and the service module is planned for today, with a bench test following up tomorrow. 

We are now in our second day at the ESRANGE Space Center getting our experiment ready for flight! In the morning there are quick meeting briefs with all the teams present and Alex Kinnaird who takes us through the day’s plan. Yesterday we also attended a presentation about the safety regulations of the compound where DOs and DON’Ts where discussed. Unfortunately, riding the rocket in a cowboyish fashion is not allowed during the hot countdown.

The daily working program is from 08:00 to 18:00 and the people here are really strict about it because after dinner there are things like sauna, nature and various games to enjoy. Yesterday for example we took a short trip up to “Radar Hill”, a very good spot to get a feel of the surroundings and appreciate the beauty that is Norrland. Here’s what we saw:


” In the background you can see the balloon launch area and the rocket launch area. The blurred bits are not image artifacts only ‘randomly’ scattered satellite dishes of which we are not allowed to take picture of 🙂 “

Monday we had the chance to do some sightseeing on our way up here. We checked out Sweden’s most beautiful public building (voted by the Swedish people in 2001) simply called Kiruna Church and the already melting Icehotel in the village of Jukkasjärvi:






(I formally apologize to Audrey for not having the time to photoshop her into the pictures but I promise we’ll take more when she arrives next week.)

It’s almost time for lunch, all the screws in the module are tightly secured with loctite and the electronics guys fixed a frustrating and annoying problem we had with the RMU board since yesterday. We are in good spirits; so here are some more pictures of the team members attending the campaign: 


“Here’s Ruslan trying to slow down the inevitable collapse of the Icehotel. “



“Jorge taking advantage of a hibernating bear.”


“A selfie of myself.”


“And Georg ‘leading’.”

We will post a live feed of the launch as soon as one will be set. Stay tuned!

Good day!*


* Appropriate greeting since we have 21 hours and 29 minutes of daylight and a soft twilight transition between days up here

It’s been a while – an update from ISAAC

Hej everyone!

We, that is Vlad, Ruslan, Jorge and me (Georg), have just arrived at Esrange Space Center for the launch campaign, and it’s high time to revive this blog. A lot has happened since the last post, and I want to give you a summary here so you all have an idea what we’re working with in the next days. For the launch campaign, which is the next two weeks, we plan to post at least a short blog post every day.

The most important news is that we had to reduce the scope of the experiment. Despite the hard work we did not manage finish all the parts, and in the end we decided not to fly the free-falling units (FFUs) at all. As you may remember, the FFUs are made up of two parts, the common unit (CU), responsible for collecting basic flight data (accelerations, GPS) as well as recovery (parachute, localizaiton), and the specific units (SU), which perform the actual scientific experiment. We had a good deal of progress with both, but when it was time for the final decision none of them was completely ready to fly.

However, we do have the fully functional rocket mounted unit (RMU), which we are very proud of, and it will fly and eject dummy FFUs. Compared to earlier designs, such as MUSCAT or RAIN, our RMU is capable of ejecting much larger and heavier FFUs, and is able to time the ejection very precisely in order to eject the FFUs into a predefined direction, despite the rocket spinning at about 3 rotations per second. Furthermore, the ejection system is completely redesigned with several improvements, such as a much lower force in the retention cables.

This RMU with the new ejection system will be tested in flight to demonstrate it’s capabilities. We have a camera on board, and we hope to capture the whole flight and in particular the ejection sequence, in order to find out just how well the system performs and how precisely the directional ejection works. Of course we will also share the video with our followers, so stay tuned for more updates in the coming two weeks!

Oh, and I case you wondered: the launch date is not fixed, as it depends on the campaign progress and the weather, but it should most likely be between 27th and 31st of May.

Greetings from Kiruna!

Looking better everyday

Hej everyone!! 😀

Most of the team is now back from their well deserved Christmas break!  We discovered with joy our beautiful custom module (which must have given a lot of work to Moraba!) and all the work our dear Romanian fellow had accomplished (while we had abandoned him without any remorse in Stockholm).

Well…not everyone is back…we lost a few people over Christmas (I mean they went home, for their studies or to start their master thesis). We are especially going to miss our electronics wizard Jorge who had been working on ISAAC since the very beginning!

However, we can now also count on our new fellows from the SCRAP team, the next KTH Rexus team. And we don’t refuse any extra-help, we are now on the home stretch: delivery of the experiment is in 13 days! (which is getting our team leader a little bit more nervous everyday). We are waiting for the delivery of parts, manufacturing  everyday to be on time. After the delivery, Georg, Ruslan and I will be heading to Bremen for the Integration Week.

It’s quite rewarding to finally see the experiment “grow” a little bit more everyday, I can’t wait to test the ejection system! So far, all the parts are fitting well together (the hours spent on CADing were not useless). Here are some pictures of the latest parts:


Hooks of the retention system


Hatch and pusher plates – the red parts are the hatch stop for the hook and the ejection spring connection, these were 3D-printed, but I started to manufacture them this morning with Lucas (SCRAP team)


D-sub bracket sent by Moraba – this is also custom made for our module, usually there is space for 3 connectors




We’ve got a rocket module!

After months of waiting and countless back and forward emails with technical drawings and specifications our rocket module has finally arrived on Swedish soil. The module is our ride ticket in the REXUS rocket and it will carry our experiment to the edge of space. You can catch a glimpse of the funky fellow below.

And they also had it in our favorite color - KTH blue!

And they also had it in our favorite color – KTH blue!

The grids supporting our experiment units inside the module also arrived the week before Christmas. Talk about timing…

Here you can see a picture of how the experiment will look inside the rocket module.

RxSU standing proud of it's aperture hole!

RxSU standing proud of its aperture hole!

TxSU showing off it's IR lamp and a couple of LEDs.

TxSU showing off its IR lamp and a couple of LEDs

As everything fits just like in the CAD all that is needed for the ejection tests are a few parts which we are to manufacture ourselves. Unfortunately for our beloved experiment people tend not to work too much during holidays 😀 but alas, we are almost done partying and we shall return with high hopes and rejuvenated spirits.

Interesting times ahead my fellow ISAAC-ers as we approach the finish line in May. I’ll be waiting for you all to return safely to Stockholm, to share stories, joy and, of course, some of that well renowned French/Swiss cheese 🙂

Happy holidays and a Happy New Year to all,


Hello everyone,

Experiment Acceptance Review (EAR) is coming up soon, more specifically, it is on this Thursday. The preparation about the project is ongoing. I wish I could show you some development on the flight dynamics. Unfortunately, I am in a trouble adding the drag torque into the dynamic model of 6 degree of freedom. Sorry for this. The look angle and the azimuth angle looked strange, very different from the previous one when the drag torque was not considered. There were so many parameters that I had no idea what lead to this strange result. According to our supervisors, in order to check all the parameters, we should start with a simple case. Therefore, I started with a very simple case,  the FFU falls down, only drag in vertical direction, no wind,  which is helpful to figure out  this problem. I feel this is not an easy task, which will take some time. I hope I can get a reasonable result soon.

Our workshop and IKEA have something in common…

…they both lack windows. No windows – no sunlight, no sunlight – no track of time. At IKEA you buy spoons, as Bill Bailey so intuitively pointed out on QI (a show which I highly recommend), but in our workshop you clamp, you mill, you lathe, you file…

With the EAR (Experiment Acceptance Review) around the corner — most likely next week on the 19th — all of ISAAC is working double shifts (except french people who, as always, chose to party instead…) in order to be as prepared as possible and of course show off. As you have seen in the previous post the electronics guys are working around the clock soldering and testing the little flat, green slices of magic that are the PCBs. We (the mechanical team), on the other hand, spend our days with oily hands and rolled up sleeves tinkering with milling and lathing machines. In just about 2 weeks we’ve gotten very far in terms of “what does this button/lever do” and now we have the confidence to tackle manufacturing issues just like …ah, I’ll let the .gif do the talking. 

So we started up easy, focusing on the Aluminium parts, while we got accustomed to the machines (see previous post by Audrey), but now we’ve moved on to “reshaping” steel into trickier parts. Just today we fiddled around with this:


A part which its designer so originally named “14.008 Corner Rounding”

Doesn’t it look cute and cuddly in the CAD ? Well, in reality it’s a nasty beast. It took us about a day to lathe the groove and cut it to its specified dimensions, losing 2 or 3 pointy, sharpy, golden tools in the process (weep not for I am sure they are in Tool-Valhalla with all their relatives and brave ancestors). Then again today, we battled for about 5 hours to cut it in half. And millimeter by millimeter we conquered it! But we’re only half the way through, with it needing to be a quarter of a cylinder and all…


Half clamped, half flying off!


Do I look content or what ?

Tomorrow we start before sunrise! And by Odin we shall slice it again!