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Amateur rocket launch reaches 121,000 feet

ddeville.com

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Re: Amateur rocket launch reaches 121,000 feet

#41

Post by mjbellantoni »

mekoka wrote: post #3

Sending your own widget up and having it bring back snapshots of other continents and a round Earth, only seconds later. What an amazing feeling it must be. Makes me wanna go dig up my old mechanics book. Can someone give a ballpark figure of how much it would cost to build something like this and how long it took them?

What a feeling indeed. The photo with the black sky and the Earth's curvature made me, inexplicably, pump my fist in the air and say "Yeah!"

This is pretty awesome.

Re: Amateur rocket launch reaches 121,000 feet

#42

Post by ryandvm »

artursapek wrote: post #38
alphadog wrote: post #24

121,000 feet = 36.88 km From Wikipedia: The Kármán line lies at an altitude of 100 kilometres (62 mi) above the Earth's sea level, and is commonly used to define the boundary between the Earth's atmosphere and outer space. That's not space. Though it's an amazing feat nonetheless.

I was waiting for the camera to stop picking up sound the whole time. It got really squeaky and full of static towards the peak but it never seemed to happen.

Being attached to the rig it could never go dead silent.

Re: Amateur rocket launch reaches 121,000 feet

#43

Post by patrickyeon »

artursapek wrote: post #38
alphadog wrote: post #24

121,000 feet = 36.88 km From Wikipedia: The Kármán line lies at an altitude of 100 kilometres (62 mi) above the Earth's sea level, and is commonly used to define the boundary between the Earth's atmosphere and outer space. That's not space. Though it's an amazing feat nonetheless.

I was waiting for the camera to stop picking up sound the whole time. It got really squeaky and full of static towards the peak but it never seemed to happen.

Sound vibrations will still be picked up in a vacuum in this case. Vibrations through the rocket body will be transmitted to the camera body (direct contact) which will then be transmitted to the microphone (again, direct contact). According to Wikipedia[1], 90% of the Earth's atmosphere, by mass, is at an altitude of 52,000 ft or lower.

[1] http://en.wikipedia.org/wiki/Atmosphere_of_Earth#Pressure_an...

Re: Amateur rocket launch reaches 121,000 feet

#44

Post by coob »

qntm wrote: post #23
jmaygarden wrote: post #16

Earlier quoted context omitted.

I thought commercial GPS was disabled above 60,000 ft.

It says here[1] "All GPS receivers capable of functioning above 18 kilometres (11 mi) altitude and 515 metres per second (1,001 kn)[56] are classified as munitions (weapons) for which U.S. State Department export licenses are required. These limits attempt to prevent use of a receiver in a ballistic missile." News to me! http://en.wikipedia.org/wiki/Global_Positioning_System#Restr...

Does that law apply GLONASS as well?

Re: Amateur rocket launch reaches 121,000 feet

#45

Post by alphadog »

user24 wrote: post #34
alphadog wrote: post #24

121,000 feet = 36.88 km From Wikipedia: The Kármán line lies at an altitude of 100 kilometres (62 mi) above the Earth's sea level, and is commonly used to define the boundary between the Earth's atmosphere and outer space. That's not space. Though it's an amazing feat nonetheless.

*feat. But I'd say that 121,000 is pretty amazing feet too...

:-) Thanks!

Corrected.

Re: Amateur rocket launch reaches 121,000 feet

#46

Post by thwest »

mhb wrote: post #32
jgrahamc wrote: post #28

Earlier quoted context omitted.

They would have to compensate for artificial curvature introduced by the cameras they are using. If you look at the images you can clearly see that effect.

They should be able to do that. No?

Yes camera calibration is a well known problem. You have some nice straight lines from the launch pad structure you should be able to do it with.

Re: Amateur rocket launch reaches 121,000 feet

#47

Post by Pyrodogg »

jgrahamc wrote: post #15
iamdave wrote: post #12

I don't have anywhere near the smarts to pull something like this off (maybe one day, one day), but I'm always so excited when people try these and they work. Awesome job

Build something else. Whatever it is that you build you end up with that awesome "I built that" feeling. Last night I hacked to 0230 on turning a set of 50 GE Color Effects Christmas lights into a 7x7 color display. No one around me really understands why this was worth staying up half the night for, but when I finally got control of the serial bus protocol for programming the lights and saw my display work under my…

At Twin Cities Maker a few of our members are undergoing a project to turn these into a large color changing glass block wall. It's been a pretty cool project to watch.

http://www.tcmaker.org/wiki/doku.php?id=projects:led_signboa...

http://www.flickr.com/photos/eagletusk/6259626384/

Re: Amateur rocket launch reaches 121,000 feet

#48

Post by nknight »

jgrahamc wrote: post #9
jcapote wrote: post #4

"As the GPS devices on Qu8k failed to log readings above 100,000 feet, the attempt is likely disqualified." would love to know what happened

Well, it could easily be that they hit the CoCom limit on the GPS units they were using: http://blog.jgc.org/2010/11/gaga-1-cocom-limit-for-gps.html Perhaps the GPS devices were disabled by speed, or altitude, and didn't have time to reset while at apogee to get the reading.

I'm surprised they didn't specifically seek out a receiver that implemented the rule correctly. Since it's an "and", not an "or", a proper receiver should have kicked back in by the time it reached apogee.

Re: Amateur rocket launch reaches 121,000 feet

#50

Post by tzs »

JabavuAdams wrote: post #35
alphadog wrote: post #24

121,000 feet = 36.88 km From Wikipedia: The Kármán line lies at an altitude of 100 kilometres (62 mi) above the Earth's sea level, and is commonly used to define the boundary between the Earth's atmosphere and outer space. That's not space. Though it's an amazing feat nonetheless.

It all depends whether you're using that metric, though -- it's all fairly arbitrary. X15 pilots were considered astronauts for exceeding 100k ft.

The threshold was 50 miles for X-15 pilots to be considered astronauts, which is 264k feet.
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