You were shown a dial and heard static. When you turned the dial and went to frequency 145.54000, you heard a message with the following URL in it:
The audio you heard was an SSTV file. When you converted it to a human-readable format, you were shown an image with the next step.
It's important to keep your password and username secret. Therefore, don't leave a post-it with a hint on your screen. Unfortunately, we did this now, and if you followed the instructions, you could log in with the username "jotajoti" and the password "frequentlygreen."
Once logged in, you could view various messages in PGP format. You could also retrieve an API key here, which you'll need later. When you decrypted the messages, the following URL emerged:
You were shown an image. If you opened it with a text editor, you'll see a URL somewhere in the file.
The login screen itself didn't reveal much, except that you could see that anything you entered was encrypted with MD5 and what the encrypted answer was. You could use a Rainbow table, for example, or simply brute-force the correct answer by trying.
You've now arrived at an API page. You'll see some documentation and the header you need to add to your requests to authenticate yourself (you got the API key itself from the previous step). By digging around in the data, you "accidentally" discovered what the next step's task was.
Now that you have access to the API and know what to do, it's still "pretty simple": You had to inject your own group into the Hall of Fame. You might even have seen a hint about next year's theme! Once you'd "injected" your group, you'd receive the URL to the final real challenge.
We need to solve this formula: ((XXX * YY) ^ 2) || ZZZZZZZ
Where XXX = the first three digits after the decimal point of the longitude at which the balloon was launched
YY = the height of the balloon in kilometers
ZZZZZZZ = the balloon's identification number
The balloon was launched at 52.099978, 5.177460. It reached an altitude of 34 kilometers, and its identification number was W2410847