The Idea
We want to send a camera up on a weather balloon to the edge of space (roughly 90,000 ft) in order to get some high altitude pictures of the earth.
This is not the first time this project has been done. We first saw it done by a group of students from MIT. The idea was intriguing not only to us, but apparently to many others as well. In the past couple of years there have been many people to attempt to do it. Many of the projects have failed.
The basic concept is to fill a weather balloon with gas (typically helium, but it looks like sometimes hydrogen or natural gas are used). You then attach a camera for the pictures and some kind of tracking device.
The Camera
A camera normally needs to have a custom firmware installed on it and runs a script from it's memory card. The script controls when the camera takes pictures. It looks like most people simply have the camera snap pictures every five seconds or so. We plan to use an old Canon PowerShot with CHDK on it.
Tracking
GPS is usually used to track and attempt to recover the balloon. Some projects use a cell phone, arduino or the like. We have chosen to keep things as simple and "off the shelf" as possible, so we will be using a spot tracking device.
Batteries
In the stratosphere temperatures can be around fifty degrees below zero (Celsius). This causes issues with most batteries, as it slows their chemical reaction which produces electricity. Some groups will substitute lithium battery packs for the typical lithium ion ones that come with most devices. The lithium variety are much more resilient to the low temperatures. What we are going to do is use chemical hand warmers next to the camera and GPS unit.
The Container
Some sort of container is commonly used to hold your gear suspended from the balloon. You can use some kind of box, an ice chest or fabricate something of your own. The container shields your electronics from the elements and insulates them. We have chosen to make ours from layers of rigid insulation board with hollowed out areas for the payload.
I am excited to see how your project turns out and if you can see the earth's curve in your photos. Having been raised by a scientist father, I was continually surrounded by half baked experiments and my father patiently waiting for results, scratching notes regarding his hypothesis, documenting every step and attempting to convince me to follow in his footsteps! As I didn't absorb the family "science genes", I have no more than surface understanding. I will,however, be checking for progress updates, rooting for success and my adventuresome spirit would like to be riding in the back seat as you search for your "downed container"... (NOT DROWNED container!) Happy Trails! :)
ReplyDelete