1992: SafetySat

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During launch, in the event of an unexpected sensor reading, SafetySat will extend prongs in all directions to secure itself and any other cubesats safely in the launch vehicle until the source of the problem can be determined.
Title text: During launch, in the event of an unexpected sensor reading, SafetySat will extend prongs in all directions to secure itself and any other cubesats safely in the launch vehicle until the source of the problem can be determined.


Ambox notice.png This explanation may be incomplete or incorrect: Created by a CubeSat so dangerous, I corrupted the image file and crashed the server (the first image upload was corrupt)- Please change this comment when editing this page. Do NOT delete this tag too soon.
If you can address this issue, please edit the page! Thanks.
Cubesat is a standard format for small satellites that can fit in a 10×10×10 cm format with a mass of less than 1.3 kg. They have been widely use by academics for research satellites, and by both small and large companies.

Cubesats are normally launched as a secondary payload often beside a deployment to the international space station. There are multiple safety rules to ensure that the cubesat cannot damage the primary payload. This design seeks to break as many rules as possible.

(from bottom left)

Americium corners
Americium is a very dense, highly radioactive substance. Depending on the amount of Americium involved, this alone could shoot the mass over the 1.3 kg mass limit.
Gun cotton
A form of nitrocellulose; it is explosive.
Crude Oil
Exxon Valdez oil spill, Deepwater Horizon explosion... need we say more? Of course the leakable volume would not be near those levels, but plenty dangerous nonetheless if it were to leak though a faulty seal...
Volatile Epoxy Seal
When this goes, everything gets coated in flammable crude oil.
Celebratory Firework
Explosive Fire Source
CFCs/Ozone-depleting CFC Spritzer
Chlorofluorocarbons (CFCs) are fully halogenated paraffin hydrocarbons that contain only carbon, chlorine, and fluorine, produced as volatile derivative of methane, ethane, and propane. Freon is a common example of a CFC, and the use of CFCs has been linked to a depletion of the Earth's ozone layer leading many countries to ban their use. So spritzing CFCs in an area closer to the Ozone layer sounds like a good idea?
Laser Pointer (Hubble-Seeking)
Aiming a red laser at a visible light telescope is really bad for the telescope in question and its optics.
Laser Pointers (Fixed)
Theses three laser points will effectively point in 3 different random directions, which is not safe for other around this Cubesat.
SDR/Software-Defined Radio (Code Editable via Public Wiki)
This counts as a huge security risk.
BIC Mini-Lighter
Fire source, resting on the can of crude oil.
Rare Earth Magnets
Very powerful magnets that have a high likelihood of messing up the electronics on nearby electronics, like other Cubesats.
Wet Sand Dispenser
Batteries (EBay)
The quality of batteries bought on the auction site can vary widely.
Solar Panel (Found)
The quality of the solar panel and the power it produces would have to be investigated thoroughly before being cleared for space flight.
Spark Plug
Fire Source, if it was plugged in to electricity. Excess mass if not.


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I was excited that I might be the first to give an explanation (because the comic was so late in being posted), but when it finally arrived, I had no way to interpret it. It was just a gigantic Γ shape (though with a rounded corner). Now that the real comic[citation needed] has been posted, I find that I'm still not very qualified to explain it. (I can guess at some of the references, but not the important ones.) I guess my only constructive comment here is encouragement to have a section (trivia?) talking about the initial failed comic image. 19:38, 11 May 2018 (UTC)

There was a broken image a xkcd and uploaded by the BOT. It's now fixed at xkcd and here too. --Dgbrt (talk) 19:48, 11 May 2018 (UTC)

Someone should point out how much damage the "extends spikes in all directions" safety measure could do. And I note SpaceX scrubbed a satellite launch with 1 minute to go yesterday because of some anomaly. Maybe the impetus for this cartoon? Yngvadottir (talk) 20:23, 11 May 2018 (UTC)

I figured today's comic was in reference to this picosat launch from India, which was denied launch in the US for being below minimum size ("too hard to track if they go offline") & thus in violation of the requisite cubesat specs: https://spectrum.ieee.org/tech-talk/aerospace/satellites/fcc-accuses-stealthy-startup-of-launching-rogue-satellites Personally I'm in favor of these sub-cubesat launches; My concern is with liability, not safety, per-se. ProphetZarquon (talk) 20:47, 11 May 2018 (UTC)

I would be concerned with safety as well, if not for the radar reflector ... seriously, this looks more like FCC wanting to destroy the company for being innovative than trying to ensure the visibility. -- Hkmaly (talk) 23:01, 11 May 2018 (UTC)
Agreed, I feel like it's less about the satellites themselves & more about vilifying anyone who doesn't adhere to an industry specification that is being given the weight of law. ProphetZarquon (talk) 08:06, 14 May 2018 (UTC)

Considering that it says the solar panel was "found", I think that implies that perhaps it was stolen? Or just literally found on the side of the road. Either way, it seems kinda shady. Carrera (talk) 22:20, 11 May 2018 (UTC)

"shady"! I see what you did there... ProphetZarquon (talk) 08:05, 14 May 2018 (UTC)

Are there any rules regarding solar panels on spacecraft? Seeing that Randall "found" it, I'm wondering if this would be a violation of any rules. Herobrine (talk) 23:41, 11 May 2018 (UTC)

What would happen to wet sand if put in a cubesat and then released? Water released into space boils and then desublimates into a cloud of ice crystals. But what would the temperature and pressure be as the cubesat was launched? Starting from wet sand at one atmosphere and whatever ambient temperature, would it cool down fast enough for the water to freeze before it was dispensed? (Release a gritty snowball.) If the dispenser is not kept at atmospheric pressure, would the water boil as the satellite was ascending to orbit? I wish Randall was still doing what-if. 01:22, 12 May 2018 (UTC)

I have no idea, but would imagine that water in sand would freeze the sand together into small clumps that could penetrate other satellites, rather than just evaporate. We must try this soon... (Kessler...) ;) --Kynde (talk) 20:40, 13 May 2018 (UTC)
In our solar system the ice line is inside the asteroid belt beyond Mars. This means water in Earths orbit exposed to the vacuum and the sun will evaporate. And the heat from the Sun is even high enough to trigger this very fast. More far away - e.g. at Jupiter - that wet sand would freeze to a dirty snowball. --Dgbrt (talk) 21:32, 13 May 2018 (UTC)

> quality of the solar panel and the power it produces
Quality of the power ? Isn't all solar power clean and green quality ? Spongebob (talk) 04:28, 12 May 2018 (UTC)

Well a solar panel's efficiency depends on how well it's made, and what materials have been used to make it. Considering that it was just "found", it may not be efficient enough to actually run the satellite, or even work in a vacuum. Then again, it's not like the satellite does much other than point lasers and explode. Carrera (talk) 05:21, 12 May 2018 (UTC)

I am totally surprised that nobody either commented on or included a mention in the explanation of the obvious misnomer of the title of the comic! Doesn't anyone else think this cubesat is the opposite of a SafetySat in every way possible, which I think is the main joke of the comic? I would update the explanation accordingly, but I'm not sure where exactly this point should be made. Anyone else want to take a crack at it? Ianrbibtitlht (talk) 21:59, 13 May 2018 (UTC)

Well, it could be very useful in satellite design classes. "Here is how *NOT* to do it." Gene Wirchenko [email protected] 04:08, 14 May 2018 (UTC)

Shouldn't a link be made to comic http://www.explainxkcd.com/wiki/index.php/1337:_Hack, about hacking satellites? 11:38, 25 May 2018 (UTC)

At the comic page scroll to the bottom and you will find this: Category:Space probes. Shall we mention them all? --Dgbrt (talk) 18:03, 25 May 2018 (UTC)

Oh, again the good old americium. 08:30, 28 May 2018 (UTC)

This cubesat made its way to Space Exploration Stackexchange: https://space.stackexchange.com/questions/28345/cubesat-design-requirements-and-safety-restrictions I leave the link here just in case we could add something from it to the explanation.--Pere prlpz (talk) 19:36, 11 July 2018 (UTC)