Editing 1992: SafetySat

{{comic
| number    = 1992
| date      = May 11, 2018
| title     = SafetySat
| image     = safetysat.png
| titletext = 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.
}}

==Explanation==
{{w|CubeSat}} is a standard format for small satellites that can fit in a 10&times;10&times;10&nbsp;cm format with a mass of less than 1.3&nbsp;kg. They have been widely used by academics for research satellites, and by both small and large companies. CubeSats have been discussed both before and after this comic, in [[1866: Russell's Teapot]] and [[2148: Cubesat Launch]].

CubeSats are often launched as an additional payload on commercial launches but also deployed from the {{w|International Space Station}} at the {{w|Kibo (ISS module)|Kibo-Module}} or other airlocks. All these satellites are orbiting the Earth in a low orbit and since they have no propulsion system they also become a part of {{w|space debris}} when they are out of control; eventually they will reenter earth's atmosphere without any further hazard.

Only a few days before this comic was released the first interplanetary CubeSats called {{w|Mars Cube One}} was launched together with NASA's probe {{w|InSight}} (now offline) aiming to the planet {{w|Mars}}.

One of Randall's influences in creating this comic may have been [https://spectrum.ieee.org/tech-talk/aerospace/satellites/fcc-accuses-stealthy-startup-of-launching-rogue-satellites controversy surrounding a commercial launch of a sub-CubeSat sized pico-satellite] from a launch site in India, after the company had previously been denied launch permission within the US, due to safety concerns.

There are multiple safety rules to ensure that the CubeSat cannot damage the primary payload. However, the joke in this comic is that [[Randall]]'s design seeks to break as many rules as possible.

Items clockwise from top left:

;Rare-Earth Magnets
:Violates CubeSat Design Specification Rev. 13 § 3.1.10.
:{{w|Rare-earth magnets}} are very powerful magnets that have a high likelihood of messing up the functioning of nearby electronics, like other CubeSats.  It might also cause the CubeSat to stick to other satellites, as the {{w|M-Cubed}} and {{w|Explorer-1 Prime}} CubeSats did.

;BIC Mini-Lighter
: Does not conform to AFSPCMAN 91-710, Volume 3 § 10.1.3, in turn violates CubeSat Design Specification Rev. 13 § 3.1.7
:Fire source, resting on the can of crude oil. The pressurized butane could also make the lighter burst, but in space without oxygen the lighter never would ignite. And even if the inside of the CubeSat contains some oxygen in weightlessness a flame would go out very soon, of course if it set off the crude oil or the guncotton then it would not matter, as the CubeSat would be destroyed.

;SDR/{{w|Software-Defined Radio}} (Code Editable via Public Wiki)
:Violates Title 47 CFR Part 97 § 97.207(b), in turn violates CubeSat Design Specification Rev. 13 § 3.4.3.2.1
:A radio which can be programmed to broadcast and receive in a range of frequencies, and formats. Software-Defined Radios are useful for development of new or modified wireless protocols, as well as for monitoring the raw waveform data of a transmission regardless of the protocols used. The radio in this comic is stated to run firmware which can be modified from a publicly editable Wikipedia-style webpage. Since anyone could change the radio's instructions, the radio could interfere with other satellites, or with the launch vehicle. This counts as a huge security risk, as ''anyone'' could edit it.

;Laser Pointers (Fixed)
: Does not conform to AFSPCMAN 91-710, Volume 3 § 8.2.2, in turn violates CubeSat Design Specification Rev. 13 § 3.1.7
:These three laser points will effectively point in 3 different random directions, which is not safe for other objects around this Cubesat.  It depends on the power of the laser pointers but, in general a laser over 5 mW can heat up and damage things given enough time{{Actual citation needed|reason=Why is a laser pointer dangerous?|date=May 2018}}. Of course, with the satellite being in orbit it could potentially mess up the optical sensors of other satellites, but it would be a matter of chance. This could also be a reference to the book ''What If?'', specifically the chapter ''Laser Pointer''.

;Laser Pointer (Hubble-Seeking)
: Does not conform to AFSPCMAN 91-710, Volume 3 § 8.2.2, in turn violates CubeSat Design Specification Rev. 13 § 3.1.7
:Aiming a laser at a visible light telescope is potentially destructive to the telescope in question by damaging its optical sensors. This is because CCD & CMOS image sensors are designed to detect finite light sources, concentrated & focused by an optical lens. Lasers produce high light levels well beyond the (comparatively) very low intensity light which astronomical image sensors are designed to detect; The energy of these excess photons can heat up the circuits between rows of photosensitive cells to the point where they overheat and fuse. For much the same reason, originates the phrase "do not stare into laser with remaining eye". Unlike the fixed laser pointers above, this one would track and aim a laser at the Hubble, with potentially disastrous results.

;CFCs/Ozone-depleting CFC Spritzer
: Does not conform to AFSPCMAN 91-710, Volume 3 § 10.3, in turn violates CubeSat Design Specification Rev. 13 § 3.1.7
:{{w|Chlorofluorocarbons}} (CFCs) are fully halogenated paraffin hydrocarbons that contain only carbon, chlorine, and fluorine, produced as volatile derivative of methane, ethane, and propane. {{w|Freon}} is a common example of a CFC, and the use of CFCs has been linked to a depletion of the Earth's {{w|ozone layer}} leading many countries to ban their use. Thus spritzing CFCs in an area relatively close to the Ozone layer may be a bad idea.

;Celebratory Firework
: Violates CubeSat Design Specification Rev. 13 § 3.1.3.
: Does not conform to AFSPCMAN 91-710, Volume 3 § 13.2, in turn violates CubeSat Design Specification Rev. 13 § 3.1.7
:Explosive fire source that could hit other satellites in the vicinity; Also potentially breaking the adjacent seal & igniting the crude oil behind it, turning it into crude oil that is also on fire. Could also set off the guncotton and result in an explosion that destroys the satellite. At the very least, the off-axis position of the firework within the CubeSat would most likely send the satellite into an uncontrolled spin, upon celebratory launch. 

;{{w|Crude Oil}}
: Violates CubeSat Design Specification Rev. 13 § 3.1.6
: Does not conform to AFSPCMAN 91-710, Volume 3 § 10.1.3, in turn violates CubeSat Design Specification Rev. 13 § 3.1.7
: § 3.1.6 permits 100 Wh of stored chemical energy, or about 9.8ml of crude oil. There appears to be more than that.

;Volatile Epoxy Seal
: Does not conform to AFSPCMAN 91-710, Volume 3 § 10.1.3, 12.1, in turn violates CubeSat Design Specification Rev. 13 § 3.1.7
:Epoxy is a substance composed of long-chain molecules which exhibit very strong adhesive bonds. Many mixtures of epoxy are flammable & produce hazardous fumes when burned. If this particular epoxy seal fails, everything within splatter range gets coated in flammable crude oil.

;Guncotton
: Does not conform to AFSPCMAN 91-710, Volume 3 § 10.1.3, in turn violates CubeSat Design Specification Rev. 13 § 3.1.7
:A form of {{w|nitrocellulose}}; an explosive. Could be set off by the firework, the crude oil, or the spark plug. Nitrocellulose {{w|Philae_(spacecraft)#Landing_events|does not work reliably in vacuum and possibly caused a failure of Philae space probe}}.

;Americium corners
: Does not conform to AFSPCMAN 91-710, Volume 3 § 9.1.1, in turn violates CubeSat Design Specification Rev. 13 § 3.1.7
:{{w|Americium}} is a very dense and radioactive substance. Depending on the amount of americium involved, this alone could shoot the mass over the 1.3 kg mass limit. The isotope <sup>241</sup>Am is used in smoke detectors but also proposed for use in {{w|Radioisotope thermoelectric generator|radioisotope thermoelectric generators}} in spaceflight.

;Spark Plug
: Does not conform to AFSPCMAN 91-710, Volume 3 § 10.1.3, 10.1.4, in turn violates CubeSat Design Specification Rev. 13 § 3.1.7
:Fire ignition source, if connected to electricity; excess mass if not. The electrodes on the spark plug are next to the guncotton which could ignite if the spark plug fires.  Additionally, sparks cause electromagnetic interference and electrical shorts.

;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. Also, it isn't clear on the design exactly what, if anything, it is supposed to power, or if it is just excess mass.

;Batteries (eBay)
:The quality of batteries bought on auction sites can vary widely, and certain batteries exposed to conditions outside their design specifications can {{w|Battery_(electricity)#Explosion|explode or leak corrosive chemicals}}. These batteries might also be connected to the adjacent spark plug. Non-rechargable commercial batteries may leak or explode if a recharge is attempted, so if this is the intention of the Solar Panel, these would escalate into an even greater risk.

;Wet Sand Dispenser
:Violates CubeSat Design Specification Rev. 13 § 3.1.2, 3.4.3
:Possible reference to the {{w|Kessler syndrome}}, which refers to a hypothetical situation wherein there are enough objects floating around in low earth orbit that collisions between objects might result in a "domino effect," each collision causing more collisions and breaking objects into smaller pieces of space debris, which increase the likelihood of further collisions. Wet sand exhibits a high grip:slip ratio, where the surface tension of the water tends to make particulates clingy. Sand (silica granules) can be very harmful to a wide variety of systems, due to its hardness & abrasive qualities. Depending upon the pattern of water sublimation in either shaded or sunlit zones, the exact behavior of various quantities of "wet sand" in low Earth-orbital space might be of interest to the designers of this and of other spacecraft.

;Title text
:Violates CubeSat Design Specification Rev. 13 § 3.4.4
:{{Wiktionary|prong|Prong}}s that extend in the event of an unexpected sensor reading at launch could damage the rocket and/or nearby CubeSats/payloads. That the CubeSat reacts to an "unexpected" sensor reading - which could include any number of readings that aren't actually a problem - is also funny, as is the fact that this is described as "safely" securing the CubeSat and any surrounding CubeSats. Along with this, it is not unlikely that this CubeSat might be the source of any internal problem that might arise; in such a situation, having such a dangerous CubeSat further secure itself would be counterproductive, if spitefully entertaining.

==Transcript==
:[A prototype for a small cube-shaped "CubeSat" satellite, with labels on various components.]

:[Labeled on top:]
:Rare-Earth Magnets
:Bic Mini Lighter
:Software-Defined Radio (code editable via a public wiki)

:[Labeled on right:]
:Laser Pointers (fixed)
:Laser Pointer (Hubble-seeking)
:Ozone-Depleting CFC Spritzer

:[Labeled on bottom:]
:Celebratory Firework
:Volatile Epoxy Seal
:Filler (Guncotton)

:[Labeled on left:]
:Americium Corners
:Spark Plug
:Solar Panel (found)
:Batteries (eBay)
:Wet Sand Dispenser

:[Labeled from within drawing in white text on top of a black rectangle:] 
:Crude Oil

:[Caption below the panel:]
:My CubeSat proposal was the first to be rejected for violating every design and safety requirement simultaneously.

== Trivia ==
*The normal sized image was originally broken at [[xkcd]] and the BOT uploaded that image here. It was just a gigantic Γ shape at first (though with a rounded corner). The problem was fixed soon, but it happened later again at comic [[1994: Repairs]].

{{comic discussion}}

[[Category:Space probes]]