How to send your teddy bear to near-space… and get it back unhurt

A view of the Earth's curvature from our high-altitude balloon

A view of the curvature of the earth from our most recent high-altitude balloon mission.


Things have changed since the glory days of Yuri Gagarin when we first reached for the stars. Now, it is easier than ever to get involved in a space mission.

The High-Altitude Ballooning project at BLUEsat UNSW brings together passionate students from a wide range of degrees to build, test and launch equipment to altitudes over 30km.

Our most recent mission was on the 5th of August, where we sent our custom-built scientific research payload up 33km to gather data on the atmosphere and capture video of the ascent.

So, you’re probably thinking to yourself, how can I do this from home?


Do you want to take stunning pictures of the curvature of the earth? Perhaps take a photo of your teddy bear against the backdrop of space?

Our main objective was to study the atmosphere to gain knowledge for future missions. This involved sensors, an onboard computer, and code to log data. We used a Raspberry Pi for computing, with an accelerometer, gyroscope, magnetometer, barometer, temperature probes and humidity sensor recording data to an SD card.

We also captured video and photos with two cameras mounted on our payload.


Without knowing where your payload is during flight, you have just launched a glorified party balloon. We used 3 discrete self-contained systems to track our flight, pictured below.

The SPOT GPS Tracker simply transmits and uploads coordinates to a website, where we can view location updates on a map. An APRS radio device, the yellow box, transmits GPS coordinates over amateur radio bands which are uploaded to an online network. The third device is a short-range radio beacon which plays a continuous tune over radio frequencies, allowing us to pinpoint the landing area.

Balloon Tacking Equipment. Left to Right: SPOT Tracker, ARPS, Radio Beacon
Tracking equipment


Typically, a mission is ended when the balloon bursts, but if you are feeling fancy, you can build a device that can remotely cut down your payload. We have developed a mechanism that runs a current through a piece of nichrome wire, which is wrapped around the rope connecting the balloon to the payload. An on-board radio receiver decodes a termination signal which we can send from the ground, causing the nichrome to heat up and sever the rope.


Before you can send anything into the air, you must seek approval from CASA, the Civil Aviation Safety Authority. You will also need to perform predictions of your flight using online prediction software, such as that found at HabHub, which will allow you to visualise the estimated flight path and burst altitude based on weather forecasts. The figure below shows a predicted trajectory for our launch.

Prediction of the stratospheric balloon's flight trajectory from Muswellbrook, NSW using HabHub.
Prediction of flight trajectory from Muswellbrook, NSW


You now need to hire a tank of helium and drive all your equipment out to your launch site. Make sure you take a toolbox and spare parts with you for any last minute adjustments.

BLUEsat's high-altitude balloon team preparing for the launch.
Final preparations

The Launch

Once you have inflated the balloon with enough helium to attain the desired lift and attached your payload, you are ready for launch. Perform a final flight prediction, check your on-board systems, turn on your cameras and cross your fingers!

The stratospheric balloon being launched by the BLUEsat team from an oval in Muswellbrook, NSW
It’s time to let go…


Watch the promotional video of our launch below:




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(2) Comments

  1. Hi There,

    I was wondering if you could help a primary school in Melbourne launch a teddy bear into Space. Other schools in the UK and NZ have done this – they have attached a GO Pro camera and a parachute to the Teddy Bear and have monitored its journey and return.

    I would be so grateful if you could please let me know if you could help us in any way.

    Thank you so much

    Shireen Armstrong.

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