1189: Voyager 1

2013-03-22T15:28:00Z

GrizzB Bacn: /* Explanation */ Cats

{{comic
| number = 1189
| date = March 22, 2013
| title = Voyager 1
| image = voyager_1.png
| titletext = So far Voyager 1 has 'left the Solar System' by passing through the termination shock three times, the heliopause twice, and once each through the heliosheath, heliosphere, heliodrome, auroral discontinuity, Heaviside layer, trans-Neptunian panic zone, magnetogap, US Census Bureau Solar System statistical boundary, Kuiper gauntlet, Oort void, and crystal sphere holding the fixed stars.
}}

==Explanation==
''{{w|Voyager 1}}'' is a U.S. space probe launched in 1977 to study the outer reaches of the Solar System and beyond. Popular press has on several occasions announced that it “has left the solar system” – at each point when a boundary has been confirmed or a major event has taken place – the fact is that there is no strictly defined and recognizable boundary of the solar system.

The alt-text lists several such possible boundaries, together with fictive humorous ones:

*The {{w|termination shock}} – the point in the heliosphere where the solar wind slows down to subsonic speed (relative to the star) because of interactions with the local interstellar medium.
*The {{w|heliopause}} – the theoretical boundary where the Sun’s solar wind is stopped by the interstellar medium.
*The {{w|heliosheath}} – the region of the heliosphere beyond the termination shock.
*{{w|Heliosphere}} – a region of space dominated by Earth’s Sun, a sort of bubble of charged particles in the space surrounding the Solar System.
*Heliodrome – yet another composition of ''helios'' "sun", here together with ''dromos'' "course". There is no astronomical object with this name, but it has been used variously in other contexts. One that became famous is a sports hall which was used as a concentration camp in the Bosnian war, see {{w|Heliodrom camp}}.
*Auroral discontinuity - another fictitious astronomic object, for ''auroral'' see {{w|Aurora (astronomy)}}.
*{{w|Heaviside layer}} – a layer of ionized gas occurring between roughly 90–150 km (56–93 mi) above the ground in the Earth's atmosphere. Popularly recognized for its use as a reference to Heaven in the writings of {{w|T. S. Eliot}} adapted into {{w|Andrew Lloyd Webber}}'s musical ''{{w|Cats (musical)|Cats}}''.
*Trans-Neptunian panic zone – this fictional zone combines the word from two subject: “Trans–Neptunian” is used in astronomy to describe stuff that occurs beyond the planet Neptune. In {{w|Outdoor education}} the “panic zone” is the opposite of the {{w|comfort zone}} when trying to learn new stuff.
*{{w|Ignition magneto|Magnetogap}} – part of an {{w|ignition system}}.
*US Census Bureau Solar System statistical boundary – a fictive boundary defined by the {{w|United States Census Bureau}}, similarly to how it defines {{w|Census tract|census areas}} for the purpose of processing statistical data about regions in the United States.
*Kuiper gauntlet – this is a play on the {{w|Kuiper belt}}, which is region of the Solar System beyond the planets, extending from the orbit of Neptune (at 30 AU) to approximately 50 AU from the Sun, notable for being full of asteroids; replacing the word “belt” with “{{w|gauntlet (glove)}}” (often spelled 'gantlet') which is a protective glove as well as “{{w|gauntlet (punishment)}}” which is a medieval punishment where one would be forced to run through two lines of men who would hit the punishee.
*Oort void – refers to the {{w|Oort cloud}}, a gigantic “cloud” of materials (mainly composed of ice) which ends around a light-year from The Sun and is deemed the (current) “edge” of the solar system.
*Crystal sphere holding the fixed stars – this refers to historical ideas about the universe, in which the stars were supposed to be fixed on a {{w|Celestial spheres|large crystal sphere}} around the Earth.

==Transcript==
:Number of times ''Voyager 1'' has left the Solar System
:[22 tally marks.]

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1189: Voyager 1