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Our neckerchief is green and black

Putting a
Cub in Space!

To celebrate the 50th anniversary of two adventurous scouts, Neil Armstrong and Buzz Aldrin, walking on the Moon on July the 20th 1969, we arranged to launch one of our Cub Scouts into space!

We planned to put the smallest cub we had into a basket below a large helium balloon. We attached a couple of cameras to record both the cub as they travelled into space, and the view down from below the basket.

We sought and were given approval from the CAA and Cambridge Airports' Air Traffic Control issued a NOTAM for a clearly defined launch window in July.

We built the craft and equipped it and, of course, we have provided all of our cubs with suitable training.

After starting the cameras rolling, and within our approved launch window from Cambridge Air Traffic Control, surrounded by most of the group from Beavers to Explorers, plus parents, we launched the cub from our impromptu facilities at the back of our hut on Flamsteed Road.

After a couple of hours flight the balloon was supposed to burst and the parachute deployed, slowing the descent to a survivable, if a tad hairy, speed. We had planned to use tracking signals to locate the remains of our cub's basket, our cub, the space souvenirs and the cameras. However, as with many projects, things didn't go exactly according to plan and our lift-off speed was lower than expected. This extended the flight time, and distance travelled considerably, which meant that the tracker's battery expired before we could make use of it and instead of landing somewhere in Essex as planned, headed off towards the Continent across the English Channel.

After travelling into space, here is where our cub landed, 350 miles away at Grange-le-Bocage in France:

There are more details on the lovely people who helped return our Space Cub further down the page


We did some astronaut training, courtesy of the Nasa Train Like an Astronaut series of training materials



We visited the Astronomy Department of the University to hear about how our solar system and galaxy are made up and to hold some actual meteorites. By completing a poster on the Solar System we were able to complete the Astronomers Badge

We made a trip on the train up to Ely to their Science Festival in Ely Cathedral to see their The Sky's the Limit exhibition with lots of space and science things going on. As well as all the space things, there was also 3D printed radio control cars, the Sanger Institute were extracting and refining DNA and someone was burning gun cotton on volunteer's hands.

Our cubs assembled under the 7m Moon floating in the nave

Saying hello to an extraterrestrial life form

Our cub's space suit dwarfed by Neil Armstrong's


For any launch from near or within controlled airspace the Civil Aviation Authority needs to be informed on form DAP1918. The CAA have brought in some rules on the sizes of payloads to avoid heavy payloads causing a risk to aircraft, but ours is well within the allowed light category. We found that permission needs to be gathered from the relevant control authority in the area which for our launch was Marshalls Airport in Cambridge, who were very happy to help us and provided us with a one hour launch window. We chose one of our typical meeting evenings, Tuesday July the 9th, 2019, about two weeks before the half centenary of when a pair of scouts named Neil and Buzz walked on the Moon. We even sought and were given approval from Scout HQ at Gilwell, which had the added advantage that the trip was therefore covered under scouting insurance.

Payload Preparation

Our payload vehicle was made using a recycled polystyrene box liner and some paracord. This provides some insulation to the batteries and most of the electronics to keep them warm in space. The side view camera is a GoClone which is cheap but needs a battery backup so that it lasts for the whole flight and is held out by some bent coat hangers. The down view camera and the 'find my landing site' solution is an old smartphone with some altitude logging and find-my-phone software and a version of the camera software that doesn't show the video on the screen so as to save battery. It too needs battery backup to be able to survive the whole trip - if the battery goes flat there is much less chance of finding the craft afterwards and recovering the camera footage.

Our payload was one of our cubs, called Douglas, with a space helmet and a 28th Cambridge green-and-black necker, and some Shrinkles that the cubs each coloured in and shrank down for the trip into space. Each one was then returned to its creator with a certificate to show it had been into space.

Total payload was then weighed. With a smartphone, a GoPro clone, backup batteries, the collection of Shrinkles cub personalised payloads and the all important cub passenger comes in at 600g

Testing the launch vehicle in the conservatory
Chosen designs were coloured in and then shrunk to 1/5th of its size for launch

Launch Vehicle

The lift for the launch vehicle was provided by a helium filled latex weather balloon, so called because they are used by meteorologists to lift weather experiments high up into the upper atmosphere.

We went for a 600g balloon to lift the 600g payload from Jezsensible on eBay. It is made from latex rubber and comes sealed in a foil wrapper to ensure as little damage to it as possible to keep the helium in as long as possible. Jez even included some gloves to keep the grease and sweat from our hands transferring onto the balloon and freezing, which would cause it to fail prematurely. It was about 4-5ft in diameter when inflated so we had to do that outdoors on a tarpaulin to prevent it from being burst by anything sharp.

The day of the launch we confirmed with Air Traffic Control that we still intended to launch as planned and they confirmed that there were no planes in our vicinity. The CAA issued a NOTAM, a Notice to Airmen which warned all airspace users of our balloon.

We filled the balloon with 10 litres of helium at 200bar, so that is 2000 litres at ground level, which is 2m3, 70cu.ft or about 1.5m or 5ft across. Eventually this balloon bursts, releasing the helium to outer space, which is a waste of a finite resource and thought needs to be given to whether this waste is justified. However, it is a tiny amount comapred to the party balloon wastage, all of which eventually reaches outer space; our balloon is equivalent to around 250 small happy birthday balloons filled with helium. With 2000 litres, our 600g payload and 600g balloon was intended to reach around 5ms-1 on the ascent, which is what we were after for a 2.5hour total flight time, ground to ground.

Included with the balloon was a suitable Tyvek parachute that goes between the balloon and the payload for the descent. The top of the parachute is attached to the balloon so the parachute is folded on the way up. After the balloon bursts, the parachute is released and the bottom has a small disc which spreads the neck of the parachute out so that it catches the air and slows the descent to around 5ms-1, much like the ascent.

Prediction at T minus 7 days
There are websites that help predict where the balloon will land. These use the predicted airspeed and direction of the wind at the variuous altitudes that the balloon will travel through to try to work out, as accurately as can be done, where the balloon may come down. However, without a tracking device (we're planning on using a smartphone with find-my-phone), getting the payload back has to rely on it being found by someone with a kind heart ...

Our payload has our Cub with his space helmet, the cub souvenirs, the cameras and batteries, all wrapped up in polystyrene both to keep the electronics warm in space and to make for a soft landing on whoever this touches down upon.

Our space capsule with the balloon being filled with helium in the background

The Launch

The launch was from the back of our scout hut on Flamsteed Road in Cambridge on Tuesday the 9th of July 2019 at around 7:15pm in the end. The whole group was assembled for the launch including Beavers, Cubs, Scouts, Explorers, Young Leaders, Leaders and parents. The downward facing camera started from a leader's hand, to a handful of cub faces, to all the cubs, beavers, scouts and leaders and well wishers and then the roof of the scout hut. Then the Railway Station and Morley Memorial School and then hopefully much of Cambridge. The cloud was at about four or five thousand feet so we probably won't get a view of the whole of East Anglia or even most of the UK as they won't be able to be seen through the cloud. We all took photos of the launch.

The cubs said goodbye to our plucky space volunteer!

Not everything goes to plan, even on painstakingly planned operations like this. In the end, when the helium was in and the payload was assembled, the spacecraft just sat there, not going up and not going down. Perhaps our helium supply had been 'cut' with nitrogen or normal air or perhaps some weight calculation had gone horribly worng but there was not enough lift.

Our space capsule didn't rise quickly enough at launch!

We had to do something! One of the battery packs was jettisonned, the one backing up the external camera. We left the one backing up the phone as we needed tracking, altitude logging and time lapse photography to survive the whole trip if we were to be able to find it again when it landed.

Even with this emergency weight jetisonning, launch velocity was only somewhere between 1ms-1 and 2ms-1 rather than the 5ms-1 we had planned for. It was slow enough for our panorama photograph, shown on the right, to capture the balloon twice (actually 2.5 times), which was pretty cool. The slower climb speed meant that the flight time was much extended, resulting in a much much further sideways travel due to the winds than we had planned for. Rough calculations at this point suggest a landing somewhere in Northern France!

The Recovery Plan

Our leaders' plan was to wait for the smartphone to get back down close enough to the ground for it to get a mobile reception and then use Google's find-my-phone to see where it has landed. We were then going to drive off and recover the payload and those all important memory cards.

However, as the flight exceeed the available battery life of the tracking device, we were very muchin the lap of the kindness of whoever found the capsule, and the weather gods if we were to avoid splashing down in the English Channel to a watery grave, never to be seen again.

We kept our fingers crossed! ....

The Discovery

In a fantastic set of text messages from the people who found our Space Cub, using the Space Cub's mobile phone, we were told that he had made it to Grange-le-Bocage southeast of Paris, some 350 miles away!

The kind people found it on a farm outside the village and went to the trouble of charging up the phone, checking out this webpage and replying to us to let us know of his safe arrival and that he hadn't landed in the Channel.

They then arranged for the capsule to be returned to us by post, which was very kind of them. Before all of this, however, he was given a Hero's Welcome tour of their village (see the video below).

Unpacking the data

The three heroines in France who found and returned our Space Cub to us packaged him up carefully with everything that survived and sent him back to us. It turned out that we had lost the sideways GoPro camera somewhere along the way but the altitude tracking still logged the route. At least until it went so high that the -60°C temperatures of Space made the phone power down.

In total our Space Cub travelled around 350 miles from the launch site at our hut in Cambridge. After release the capsule climbed steadily, albeit rather slowly. After crossing Braintree, when we lost contact with it directly, and passing through some warmer and colder air which affected the altimeter sensor, it continued in a southeasterly direction, leaving the Essex coast over Foulness Island and then briefly crossing Kent at Ramsgate to reach a maximum height at this point of 7112m, 23,300ft or about 4.5miles up. However, as this was by now after 10pm the sun set on our intrepid Space Cub.

Nightfall had the unfortunate effect of causing the balloon to deflate a little, reducing the lift it produced until it was no longer enough to raise the balloon. The capsule therefore slowly descended as it continued southeast, crossing the channel at a respectable 5000m, 16,500ft or about 3 miles up directly over Calais. Slowly the capsule descended, lower and lower until, around 4am it touched down lightly just south of Amiens near a village called Epagny. The balloon was still aloft but there wasn't enough lift to get it off the ground. Perhaps at this point the sideways GoPro camera became stuck on a tree, a fence, a bush or a wire.

At 06:52am the sun came up and the gas in the balloon started to warm up. If it had been caught by the GoPro camera catching on something then the capsule must have eventually have torn itself free, possibly leaving the GoPro behind. This looks likely because after lift-off it rose quickly into the air as if it had been held down for a bit. Climbing all the time, this time in the full sun, the capsule went up and up.

At 18,000m, about 60,000ft, the temperature of space reaches about -60° Centigrade as the capsule entered the Tropopause at the top of the Troposphere at a little after 11am on the second day of the flight. Here the batteries in the phone and even the special backup battery pack could not continue to generate enough current in the extreme cold to keep the altimeter running and the phone powered down. The maximum recorded (but unlikely to be the maximum it reached) was 18,116m, around 60,000 feet and marks the point where the capsule entered the Stratosphere. Following the trajectory and given the specs of the latex balloon we used we estimate that the burst was another 10km, 6 miles, higher at just over 28,000m, about 92,000ft or about 17.5 miles up, somewhere over the town of Troyes. Interestingly, given the curvature of the Earth, you can just about see Cambridge from 28,000m above Troyes.

Around a quarter to one, BST, we calculate, on Wednesday the 10th, 15½ hours after launch, the helium filled latex balloon burst at just over 28,000m and the descent was rapid under the small but functional parachute. Down came the capsule, probably in only around 1¼ hours so about 2pm, and landed in a field on the south eastern outskirts of the village of Grange le Bocage.

It would appear that the capsule landed in some ripening wheat and was therefore not discovered until the Sunday the 3rd of August, some four and a half weeks later when the combine harvester came out for the harvest. His plucky spirit must have kept him going during his isolation. Luckily the eagle-eyed farmer spotted him before he was eaten by the enormous cutting blades that reap the corn and handed to the three French heroines who returned him to us.

Hero's welcome

The three who found the Space Cub gave him a hero's welcome and a tour of their village. He visited their school and looked around their beautiful church before wrapping up tight for the journey back to Cambridge in the post.

Not easy to spot in a corn field

He looks a little frightened

All of the shrinkles survived the trip!

Our three French heroines!

A video from the footage shot by our Cub in Space's french recovery team, Les Trois Héroïnes

It turns out that the finder had been a scout when she was younger; a great Scout carries on doing good deeds for others their whole life!