The GPS cell phone we used to track the location of our vehicle lost reception soon after launch (at an elevation of ~2500 feet). Although we had expected to lose contact with the balloon, the altitude of “last-report” was much lower than expected.
After loss of electronic contact, we could continued to track the capsule visually for about half an hour until the glare of the sun prevented further viewing.
GPS information recorded in the flight logs reported a maximum altitude of 19,853 feet due to software limitations. With some simple approximations (linear extrapolation of velocity – a fair assumption justified after looking through flight trajectories of similar balloons), we estimated that our balloon achieved an altitude of about 93000 feet before returning to the earth. The balloon’s ascent took about 4 hours, and its descent took 40 minutes.
 Earth from 93000 feet. Long Island in the background.
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 Glowing from the sun
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 Our balloon popped at around 93000 feet, beginning its 40 minute descent
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 The falling balloon
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人只有看到宇宙的广阔后才知道自身的渺小，想起那句富贵如浮云，钱财如粪土。在仰望星空的时候，心胸也变得宽广了
我也来了 朋友 咱们 是咱们中国的吧
You guys given us hope, $150 can do what NASA did. Thanks~!!
You had a great ideea, good luck in future projects!
Nice photos
牛X
感谢你们为民用航天做出的贡献！
u guys remind us that innovations start from simple experiments
Brilliant Guys!!
I’ve heard your interesting job from a Chinese SF magazine. Wish you guys can go further…
你们怎么那么性感呢，佩服ing
Thanks for the inspiration. I’m doing this! It is a great fun, experiment. Retrieval should a little trickier here in Louisiana with so much swampland and marshland, not to mention the Gulf of Mexico to the south. I’ll pick a day with the right projected path.
I have a question: You say software limitations prevented you from reading Altitude from the GPS phone after 19,000 feet. Is this an avoidable issue? Is it buffer size issue? Or some numerical overflow in the phone’s data structure? Is there something I can do to get altitude from the same Motorola phone all the way up (and down).
Bill Wimley
@ bill Wimley
well the cell phone needs to connect to the internet to give its position. at about 17,000 – 20,000 you loose cell tower reception. the phone still gets a gps signal but it cant update its position on the internet untill it falls again. I was thinking about ways to solve this proplem and the only thing I came up with is to have 2 cameras. one to take outside pictures and one to take pictures of the phones’s display to read its position ( just to see its max altitude).
That’s some real exciting science your guys are into! I’m thinking that you should be able to take all the pictures and make a movie using Windows Moviemaker. You might have to cut out some of the boring stuff (4 hour accent), but it would be a blast to see the launch, the balloon pop and the decent along with the landing. You might consider using multiple cell phones to get multiple angles. One down, one up (to show the balloon status) and one looking out the side (catch the curvature of the earth better maybe?). You might even consider using a cheap HD SD flash card video camera as your video recorder rather than a cell phone (keep the cell phone for the GPS of course). You can probably get the video camera for less than $200.00. Just a suggestion.
But…WAY COOL science! Keep up the good work!
HJ :O)
That’s great！
棒极了！
Awesome idea!!
congrats!!
Awesome, guys! We all witness here what passion, creativity and perseverance can establish! A great project which gives people a big smile and a good feeling in strange and sometimes hard times. Thanks!
Greetings from The Netherlands, Anthony.
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Moury Roberts
“dofollow”>flights to Melbourne
good job guys
good job.
it think that it id so cool that you are doing these projects
The responses to your success is good example of the power of networks and collaboration. Already, others have suggested improvements that can be used to improve the design. This is a great example of open-source device development.
See Democratizing Innovation (http://www.mit.edu/people/evhippel/democ1.htm) by Eric Von Hippel, MIT Press.
Its awe inspiring. Great going guys!
Hi Justin,
I saw this on CNN news.
It was amazing. kkk
Anyway, Happy new year 2010!!