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Explain xkcd: It's 'cause you're dumb.
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We have an explanation for all 2 xkcd comics, and only 36 (2%) are incomplete. Help us finish them!

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Airplanes and Spaceships
Despite having now taken three months longer than the airplane people, we're making disappointingly little progress toward the obvious next stage of vehicle: The Unobtanium-hulled tunneling ship from the 2003 film 'The Core.'
Title text: Despite having now taken three months longer than the airplane people, we're making disappointingly little progress toward the obvious next stage of vehicle: The Unobtanium-hulled tunneling ship from the 2003 film 'The Core.'


Ambox notice.png This explanation may be incomplete or incorrect: Created by a TUNNELING AIRPLANE-SPACESHIP. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.

This comic is pointing out that more time has elapsed since the first spaceship flight, than previously elapsed between the first airplane flight and the first spaceship flight.

Airplanes and spaceships are often considered to be related vehicles, under the term aerospace, with degrees in aerospace fields often having aeronautics (airplanes) or astronautics (spaceships) tracks. The jump in technology and performance between the first airplane and the first spaceship was enormous: the Wright Flyer had a max speed of 30 mph (48 km/h), and the first flights reached only about 30 feet (9 m) above ground, with distances of only 120 to 850 feet (260 m). In comparison the Vostok 1 mission of Yuri Gagarin reached orbital velocity of 17,500 mph (28,000 km/h), a minimum altitude of 91 miles (480,480 ft; 146 km), and traveled once around the earth (about 25,000 miles or 40,000 km). This represents an increase in performance of between about 600 and 150,000 times.

By contrast, an equal amount of time has passed between the first spaceflight and the publish date of this comic, but aeronautical performance has not improved much at all. Although the Apollo mission broke speed and altitude records, and later space missions extended the distance traveled in a single flight by sustaining Earth orbit for longer, the overall technology and performance is not much different than that used during the first space mission.

It is one of the typical takes by Randall to try to make people feel old. Flight seemed old news when the Apollo mission started, so people who lived through the space race, will now feel very old since there where alive back when the space race is new, and that is now old news. This take is also used in the title text.

The title text refers to the 2003 film The Core. In this film, there is an instability in the Earth's magnetic field, so a team of scientists attempt to drill to the center of the Earth and set off nuclear explosions to restart the rotation of the Earth's core. To do this, they travel in a vehicle made of "Unobtainium" that can withstand the heat and pressure within the Earth's crust. Randall is sad to report that there is little progress being made on creating this vehicle. Incidentally, The Core is a film which represents science and engineering wrong in many, many aspects. There is a long list of flaws.[1][2] [3] For instance, if a material is resistant to the extreme heat and pressure of the Earth's core, then the significantly cooler and less forceful techniques of human metallurgy would certainly not be able to work that material at all, let alone craft it into a functional hull for a vehicle.

Randall makes sure to mention that the movie is from 2003, so 15 years old. Many people are surprised when realizing that an movie they saw "recently" is now so old that children born that year no longer need their parents guidance when watching it.


[A timeline is shown with three dots on it. Each dot has a label beneath the dot, and the two intervals between the dots are also labeled, with lines indicating which dots are belonging to that label.]
Dot 1
December 17, 1903
First human airplane flight
Dot 2
April 12, 1961
First human spaceflight
Dot 3
Interval 1-2
57 years 4 months
Interval 2-3
57 years 7 months
[Caption beneath the frame:]
Spaceships are now older than airplanes were when we flew our first spaceships.

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