3234: Europa Missions

2026-04-22T14:00:35Z

104.28.159.187: /* Explanation */

{{comic
| number = 3234
| date = April 17, 2026
| title = Europa Missions
| image = europa_missions_2x.png
| imagesize = 515x274px
| noexpand = true
| titletext = Before resurfacing, they promise to inspect the ice for any evidence of hockey-playing life.
}}

==Explanation==
In recent years, multiple space agencies have sent spacecraft to observe Jupiter’s moon {{w|Europa (moon)|Europa}}. In part, this is because, according to {{w|NASA}}, the moon could be a candidate for life due to the presence of a subsurface ocean and (possibly) {{w|hydrothermal vents}}. The first two craft — the {{w|Europa Clipper}} and {{w|Jupiter Icy Moons Explorer}} (Juice), respectively — will investigate the ocean, topography and chemistry of the moon, to help in searching for signs of life. Europa's ocean is frozen on top — the whole surface being solid ice with no exposed liquid, except perhaps at the bottom of any transient deep crevasses — which is why it described as a "subsurface ocean".

A {{w|Zamboni}} is a vehicle that is meant to quickly resurface ice rinks that have been worn down — not a scientific mission or a transport for other scientific missions. The comic describes a non-existent spacecraft known as the ''Zamboni Voyager'', operated by the {{w|National Hockey League}} (NHL). The spacecraft is carrying a Zamboni because the NHL is trying to 'expand the league'. Normally, expanding a sports league would involve, at the very least, forming a new team in a city which did not have one. In this scenario, they appear to be more literally trying to expand the available space for play, by resurfacing Europa to make it viable for hockey-playing. (Although Europa is the {{w|Europa (moon)#Surface environment|smoothest known body}} in the solar system, it's probably not smooth enough for playing hockey{{Citation needed}}.) Hockey in reduced gravity — Europa's gravity is less than 1/7 that of Earth — would be {{What If|124|an interesting idea}}.

The title text talks about finding hockey-playing life on Europa, which would be unlikely, as any life on Europa would exist underwater, where it's difficult to play hockey.{{cn}} In addition, any conceivable culture(s) there would almost certainly be extremely different from Earth's, so even if the lifeforms on Europa do have entertainment similar to sports, it's unlikely that they have even {{w|Convergent evolution|remotely similar}} rules or equipment. If, though, there were intelligent non-hockey-playing life on Europa, the NHL may consider them fair game as a virgin market for their product.

On top of that, making a spacecraft to send a Zamboni to Europa would be very difficult, as 14,000 m/s of delta-v (a measure of the total change in velocity required to transfer between orbital or 'ground' locations) is needed. With a typical Zamboni weighing five tons, a very heavy rocket would be needed. Europa clipper weighs about six tons, which is comparable to a heavy Zamboni. That particular spacecraft will not perform an orbital insertion or a landing, but only a fly-by to save fuel. Even then, it needs a fully expendable Falcon Heavy, the largest commercially available rocket (as of the comic being published), to achieve the fly-by. A landing would need much more available delta-v for the final approach.

If whoever was talking (e.g. NASA) tried to stop them, something like an SLS launch with more payload capacity may not even be possible. Even with an SLS, successfully achieving a propulsive landing would be very difficult, as demonstrated by {{w|IM-1}} and {{w|IM-2}}, which both failed to land on our own Moon. A normal Zamboni is probably not hardened against Jupiter’s intense radiation environment and, unless adapted for robotic remote control, the life support system for the operator would greatly increase the total weight of the mission. Also, the water in a Zamboni would freeze.

==Transcript==
:[Cueball's upper body is shown; he is in front of an image of a spacecraft.]
:Cueball: There are now three spacecraft headed to Europa:
:Cueball: NASA's ''Europa Clipper'', which investigate Europa's subsurface ocean,

:[In a longer shot, Cueball, Ponytail, and Hairy are all shown standing in front of another spacecraft image, with Cueball gesturing at it.]
:Cueball: ESA's ''Jupiter Icy Moons Explorer'', which will study the topography and chemistry of Europa and the other moons,

:[Another closeup on Cueball, who is in front of an image of a Zamboni with a firing rocket nozzle on its bottom.]
:Cueball: And the NHL's ''Zamboni Voyager'', which plans to resurface Europa.
:Voice out of frame: Oh no.
:Cueball: We tried to stop them, but the league is set on an expansion.

==Trivia==
* The [https://www.explainxkcd.com/wiki/images/archive/f/fd/20260418170145%21europa_missions_2x.png original version of the comic] incorrectly referred to the "Jupiter Icy Moons ''Orbiter''" rather than "Jupiter Icy Moons ''Explorer''."

* This comic was created at around the time of the start of the season's NHL playoffs.

* This comic was posted 10 days after April 7, 2026, a pivotal date in ''{{w|17776}}'' — a space-probe related and sports-related webcomic which features Jupiter Icy Moons Explorer ("Juice"), the space probe mentioned in this comic, as a main character. (While the webcomic began in 2017, it received another wave of popularity in the lead-up to April 7, 2026, the date on which humans stopped being born (and essentially stopped dying and aging) within the story's fiction.)

* Kerbal Space Program is a great way to learn the basics of orbital mechanics.

{{comic discussion}}<noinclude>

[[Category:Comics edited after their publication]]
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Ponytail]]
[[Category:Comics featuring Hairy]]
[[Category:Space probes]]
[[Category:Sport]]

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3234: Europa Missions