Title text:
I need to push some updates to the remote sensing instruments, which are there to measure the surface and definitely not do anything else.
Transcript:
Transcript will show once it’s been added to explainxkcd.com
Source: https://xkcd.com/3308/
Yes, but they are refering to the title text, which is a "secret" message when you mouseover the image on xkcd's website.
The "juice" bit? You say something has more "juice" if it's more volatile, e.g., explodes.
In case you aren't joking, it's written in the post here :