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| Slingshots |
 Title text: In my reboot, Dennis the Menace was just trying to send Mr. Wilson a nice comet, but accidentally wiped out his dinosaur garden. |
Explanation
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This explanation may be incomplete or incorrect: Created by a WRIST ROCKET SMUGGLED INTO MASSACHUSETTS - Please change this comment when editing this page. Do NOT delete this tag too soon. |
The slingshot (in this comic, styled "Regular Slingshot") is a hand-held device used for accelerating small projectiles, such as stones or steel balls. In an earlier form, the concept had existed since ancient times, and has been used for personal defense and for hunting game such as squirrels, birds and Philistines through skillful use of its mechanical advantage and rotation. The more modern "forked stick and elastic" version (known as a catapult, in the UK) acts by a pull-back-and-release action, and has become associated with youthful recklessness (or an outright tendency towards vandalism), but is also the basis of manufactured sport/hunting devices as well as the more organic child-made contraptions.
The gravitational slingshot, or gravity assist, is not a device but a term used to describe how gravity may alter the path of an object in space, such as a spacecraft or an asteroid. A gravitational slingshot generally involves a small object passing by a much more massive object, which turns the smaller object's trajectory, trading momentum and kinetic energy between the two bodies. The smaller object can undergo a large change in velocity, "paid for" (in the sense of conserving the momentum and energy of the system) with a negligible change in the velocity of the more massive body.
This comic humorously compares the two, in tabular format.
| Regular slingshot | Gravitational slingshot | |
|---|---|---|
| Used for hunting | ✓ | X |
| Used for sport shooting | ✓ | X |
| Used for spacecraft propulsion | X | ✓ |
| Large online enthusiast community | ✓ | ✓ |
| May have caused dinosaur extinction | Probably not | Maybe |
| Used by Dennis the Menace to terrorize Mr. Wilson | ✓ | Not yet, but I'm pitching a reboot |
The first four categories accurately reflect reality. As a hunting tool (and as an offensive weapon), recent designs have been claimed to propel a projectile with more force than .22 and .38 caliber pistols. Consequently, several communities have prohibited the possession of such slingshots, which may be called "wrist rockets". The state of Massachusetts, where cartoonist Randall resides, is one of those communities. Gravitational slingshots would be inefficient and overkill for such purposes, as well as being difficult to achieve sufficient accuracy and specificity.
Conversely, gravitational slingshots are a useful way to change the velocity of a spacecraft without having to use large amounts of fuel, whereas building a regular slingshot capable of propelling a spacecraft is likely to be impractical - not to mention the destructive/fatal consequences, to vehicle and cargo, of near-instantaneous acceleration to useful speeds, such as the Mach33 required for an object at sea level to escape Earth's gravity, especially when there's an atmosphere present.
Both types of slingshot excite interest among many people who may form online communities to discuss them, but for quite different reasons, and the size of overlap between these communities is uncertain.
The fifth category ventures into the absurd, at least with respect to "regular" slingshots, which did not exist (so far as we know) at the time of the Cretaceous-Tertiary extinction event. (Humans, which invented them, did not exist at that time. Use of slingshots would therefore require some other contemporaneous intelligent species to have invented them, or some kind of time travel.) However, it is likely that the event resulted from the impact of a space-rock that was perturbed into an Earth-crossing orbit by a planet such as Jupiter, given at least a minor gravitational slingshot on its way to eventually crashing into the Earth.
The sixth category references the long-running comic and cartoon character Dennis the Menace (USA), in which the titular character unintentionally harasses neighbor Mr. Wilson with (regular) slingshots and other devices and behaviors. In Randall's projected reboot of the franchise, which is elaborated on in the title text, Dennis trades his regular slingshot for a gravitational slingshot. By miscalibrating his ammunition, or the force of his slingshot, he turns a demonstration ("a nice comet") into a destructive event (the loss of Wilson's dinosaur garden). The reference is to the relative size and velocity of the space objects responsible for, respectively, comets and "meteors" versus asteroid impacts.
Transcript
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This transcript is incomplete. Please help editing it! Thanks. |
- [A table grid with two columns and six rows.]
- [Two column labels placed above the respective columns, six row labels to the left of the respective rows.]
- [Column 1:] Regular slingshot
- [Column 2:] Gravitational slingshot
- [Row 1:] Used for hunting
- [Tick]
- [Cross]
- [Row 2:] Used for sport shooting
- [Tick]
- [Cross]
- [Row 3:] Used for spacecraft propulsion
- [Cross]
- [Tick]
- [Row 4:] Large online enthusiast community
- [Tick]
- [Tick]
- [Row 5:] May have caused dinosaur extinction
- Probably not
- Maybe
- [Row 6:] Used by Dennis the Menace to terrorize Mr. Wilson
- [Tick]
- Not yet, but I'm pitching a reboot
Trivia
The "Dennis the Menace" that the Randall refers to, familiar to those in the US, is not to be confused with the other long-running comic and cartoon character from the UK, also called Dennis the Menace, who has a surprisingly similar premise and identical date of creation but is more wilfully disruptive and capable of far more 'cartoonish' behaviour (which might well include planetary-scale fork-stick slingshots/catapults). Mark Hamill is a fan of the British character (possibly from his time filming the original Star Wars films in the local studios), and also has some experience with (fictional) disruption of planets by constructed weapons.
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