In 2012 I created a successfully funded crowdfunding campaign. This project, "Little Astronaut", was about to launch a weather balloon and make automated pictures and videos from an altitude of 30000 meters, which is the earths stratosphere.
I was able to launch this mission twice, so I had enough video material to let my cousin, Michael Neumann, make this video:
I'm really fascinated by this view and I guess so are many others. So you might have the question: how can I do this?
In this tutorial I'll try to give you all the informations you need to make your own near space mission.
1. How It Works
The basic behind those missions is to put a payload, like a little polystyrene box, on a weather balloon, the balloon will, filled with helium, ascend to an altitude of about 25000 to 35000 meters. Because of low air pressure on that altitude the balloon will expand, eventually burst and fall down to earth again.
But how can I find it when it lands hundreds of kilometers away from it's starting point?
You put a GPS sender in the payload, simple as that! And here is the risky part. There is a chance that you can't find your payload anymore because of various reasons. You should always have that in mind!
2. What Do You Want To Do?
There are several things you can do with a weather balloon in the stratosphere. You can make pictures, videos, you can analyze data, there are even lots of projects were a company or group just clips a thing right before the camera to say "this is the first [whatever] in the stratosphere.
On my first mission I tried to pack my payload with two GoPro and two normal digital cameras. It wasn't even able to fly away.
The common weather balloon can hoist a payload with a weight of about one kilogram, so you should be aware of what you want to do with that project because you are limited.
3.1 The Balloon
Well, you obviously need a weather balloon for every flight, ... you know, because it bursts.
I think eBay is a good place to get them, and the usual one you will find will be an 800 to 1000 gram latex rubber balloon from the producer "Totex". Don't be afraid of how the balloon or the carton of the balloon will look like. Most of them are very very old, but they're covered with talk powder and they never saw the sunlight.
When you fill it with helium, try to use sterile gloves and a plastic plane.
But which balloon can hoist how many grams of payload? And how many cubic meter of helium do I need?
You have to do much research and search on google for other guys who might wrote down those informations and hope that everything will go as planned... IF you would be me in 2012.
But if you are you and now is now, then you will find some technical details you can orient on here:
- 800g Balloon · 2.5m³ Helium · 800g Payload · ca. 30km
- 1000g Balloon · 3.0m³ Helium · 1000g Payload · ca. 32km
- 1200g Balloon · 3.3m³ Helium · 1200g Payload · ca. 33km
- 1500g Balloon · 4.2m³ Helium · 1500g Payload · ca. 35km
And this is how your balloon might bursts:
3.2 The Payload
The payload is the box or container you stick to the balloon. Which one you need depends on what you want to carry. A camera, Raspberry Pi computer or whatever you want to hoist to the stratosphere.
Since I used at least two GoPros and a normal digital camera, I had to cut holes in the box like the one you can see on the picture.
Quick side note to the usage of a GoPro. You have to use anti fog insets or your video will be blurred from about 3000 meters.
I used a kitchen gram weighing machine to have a good overview about the whole weight of my payload.
Wait, you used a normal digital camera? But how did you made the photos up there?
I used a Canon digital camera which was "Canon Hack Development Kit" ready. CHDK enables hidden features to the camera in which you can program things like "make a photo every 10 seconds", and that's the trick.
You should maybe put a pocket warmer into the payload because it's really cold some kilometers above the earth.
Okay okay, and the GPS sender?
Yes, of course. You need a GPS sender which can send SMS. I used the "Simvalley GT 170". Configuration was a bit tricky and not that easy because it's a relatively cheap product, but it worked well at the end. You should test it before you start the mission. Take it with you to work and double check with Google Maps if it's precise enough. You obviously also need a prepaid SIM card.
3.3 The Framework
You remember? At some point I said something about "the balloon will fall down to earth again". You can reduce the speed of falling with a mini parachute for mini rockets.
Also the balloon will shake the payload, but you can contain the shaking with a good framework. We didn't had a good one, so I have no images of it. But here is a sketch you can take a look at:
4. The Law
I launched my missions in Germany, so if you live in another country you have to check it by yourself.
In Germany you only have to contact the German Air Navigation Services. Send them an email with all the informations about when, where and what do you want to launch the mission and after a couple of days you'll get your permission via email. It's for free! Yep, no kidding, it's really for free and super easy to get!
5. Useful Informations And Resources
On both of my flights I had to drive more than 300 kilometers far to pick up the fallen payloads, so you should have a car available.
I had to pick the first missions payload from a tall conifer in a forest, so you should have a plan how to do this if your payload also lands on a tree.
Put a letter with some contact informations and what this is about directly on your payload. If a fellow citizen will find it, she or he will maybe not call the cops. In my case I had to talk to a nice police officer after my second flight because the farmer who found my unidentified flying object was a bit scared. Of course there were no consequences since I had a permission, but the farmer had a really exciting day.
Here you can find a really cool global map of wind and weather:
I had fun to launch this balloons and the videos and photos I got from it were stunning awesome! There were hundreds of other people which had realized such a project and there were tons of ideas about what to bring up into the stratosphere. But at the end there is this feeling which you will get when you look at your visual material and think "Woooow! I made pictures from above the earth!".
I hope this answers all the important questions about how to launch a weather balloon to stratosphere.
Leave me a comment on twitter if you think this article is good, or if you find some grammar mistakes :)