1308: Christmas Lights

2013-12-26T00:59:13Z

HappMacDonald: /* Explanation */ changed LED to "light source" for the smaller red and green spectra, and changed irrelevant mention of "colored balls" to christmas lights, since every other spectra represents light emission instead of reflection.

{{comic
| number = 1308
| date = December 25, 2013
| title = Christmas Lights
| image = christmas_lights.png
| titletext = Merry Christmas from xkcd!
}}

==Explanation==
{{incomplete|Check grammar, check spectra and reference good fits to what is here}}
Each light in this Christmas scene is represented by its {{w|electromagnetic spectrum}}, which shows in a graphical form how much energy is radiated by each wavelength of light.

These graphs cover only the visible radiation plus some infrared and some ultraviolet. There are 4 distinct spectra in this comic:

In the center of the image, between Beret Guy and the couple Cueball and Megan appears a light spectrum of a fire, notable because it emits a lot of energy in the infrared band (The left zone of the spectrum), emitted typically from hot sources, and in the red and orange zone (typical colors of a fire). The spike toward the left hand side of the spectrum is probably the 4.3 µm resonance frequency of hot CO2 characteristic of burning hydrocarbons (see [http://en.wikipedia.org/wiki/Flame_detection#Emission_of_radiation here)].

In the right of the comic appear some spectra arranged in the form of a Christmas tree. There are 3 different spectra in this "Christmas tree":

At the top appears a complex spectrum, possibly that of a white LED (see [http://led-brdf.wikispaces.com/Introduction+to+LEDs here]), representing the tradition in some cultures of putting a star at the top of the Christmas tree.

In the branches there are two simpler spectra, one with a peak in the green zone, representing a green light source, and other with a peak in the red zone, representing a red light source. Both of these represent the tradition of putting colorful decoration in the tree, in this case apparently red and green colored Christmas lights.

==Transcript==
Merry Christmas from xkcd!

{{comic discussion}}
[[Category:Comics featuring Megan]]
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Beret Guy]]
[[Category:Comics with color]]

1253: Exoplanet Names

2013-08-19T23:10:06Z

HappMacDonald: Explanation for "Neil Tyson's Mustache"

{{comic
| number = 1253
| date = August 19, 2013
| title = Exoplanet Names
| image = exoplanet names.png
| titletext = If you have any ideas, I hear you can send them to <nowiki>iaupublic@iap.fr</nowiki>.
}}
==Explanation==
{{incomplete|1253: Exoplanet Names}}

On the 14th of August, the {{w|International Astronomical Union}} (IAU) [http://www.iau.org/science/news/179/ issued a document] about public naming of astronomical objects. It stated, "IAU fully supports the involvement of the general public, whether directly or through an independent organised vote, in the naming of planetary satellites, newly discovered planets, and their host stars.". It also contained, amongst other things, guidelines that suggested names should meet. These include stipulations such as "16 characters or less", "preferably one word", being "pronounceable (in as many languages as possible)", "not too similar to an existing name of an astronomical object", avoiding commercial names, and being "respectful of intellectual property". If we go down the list, we can see that many of Randall's suggestions do indeed violate the guidelines. Which is probably part of the joke.

The document also states that suggestions may be sent to the email mentioned in the title text.

{| class="wikitable"
|-
! Star !! Planet !! Suggested Name !! Explanation
|-
| rowspan=7 | {{w|Gliese 667 C}} || {{w|Gliese 667 Cb|b}} || Space Planet || A very unoriginal name: Every planet is in space.
|-
|{{w|Gliese 667 Cc|c}} || PILF || Pun of {{w|MILF pornography|MILF}}, i.e. ''Planet I'd Like to Fuck''. Planet c is a relatively hot planet, within the habitable zone.
|-
|{{w|Gliese 667 Cd|d}} || A Star || "A Star" is obviously a bad name for a planet; "A Star" is also the name for the character {{w|asterisk}}.
|-
|{{w|Gliese 667 Ce|e}} || e'); DROP TABLE PLANETS;-- || A reference to {{w|SQL injection}}, riffing off of [[327|comic 327]], which featured a boy named <code>[[Robert'); DROP TABLE students;--]]</code>. The idea here is that the IAU would enter the name into their system and promptly lose all of their data pertaining to planets. Note that Planet e is located in the habitable zone of the star system.
|-
|{{w|Gliese 667 Cf|f}} || Blogosphere || rowspan = 2 | Weird ''{{w|blog}}''-related terms are a recurring theme in xkcd. See, for instance, [[181|comic 181]].
|-
|{{w|Gliese 667 Cg|g}} || Blogodrome
|-
|[http://exoplanet.eu/catalog/gj_667c_h/ h] || Earth || Astronomers recently found a second Earth ([[1231: Habitable Zone]]). But maybe they just have to adjust their telescopes.
|-
| rowspan=5 | {{w|Tau Ceti}} || [http://exoplanet.eu/catalog/tau_cet_b/ b] || Sid Meier's Tau Ceti B || This refers to the game {{w|Sid Meier's Alpha Centauri}}.
|-
|[http://exoplanet.eu/catalog/tau_cet_c/ c] || Giant Dog Planet || {{w|Canis Major}}, Latin for "greater dog". This constellation contains {{w|Sirius}}, the brightest Star in the night sky, it's also known as "Dog Star".
|-
|[http://exoplanet.eu/catalog/tau_cet_d/ d] || Tiny Dog Planet || {{w|Canis Minor}}, Latin for "lesser dog", just another star constellation.
|-
|{{w|Tau Ceti e|e}} || Phil Plainet || {{w|Phil Plait}}, a.k.a. The Bad Astronomer.
|-
|{{w|Tau Ceti f|f}} || Unicode Snowman || The Unicode character [http://www.fileformat.info/info/unicode/char/2603/index.htm ☃] is a reference to the planet's estimated surface temperature of -40°C. But this name would be pronounced differently in different languages.
|-
| {{w|Gliese 832}} || {{w|Gliese 832 b|b}} || Asshole Jupiter || This massive planet orbits a {{w|red dwarf}} star at the longest known period of 3416 days at this category.
|-
| rowspan=6 | {{w|Gliese 581}} || {{w|Gliese 581 b|b}} || Waist-deep Cats || {{w|Waist Deep}} is an action film from 2006, the {{w|Lolcat}} meme does not need any further explain.
|-
|{{w|Gliese 581 c|c}} || Planet #14 || One of the earlier discoveries. Reported to be the first potentially Earth-like planet in the habitable zone of its star, though that is in doubt now.
At our {{w|Solar System}} the number of planets did increase to 15 in 1851, at that time astronomers count larger asteroids also as planets ({{w|Definition_of_planet#Minor_planets|Minor planets}}). Maybe Randall did use other sources, but he jokes about the status of {{w|Pluto}} not known in 1851.
|-
|{{w|Gliese 581 d|d}} || Ballderaan || A {{w|wikt:balls|crude pun}} on the planet {{w|Alderaan}} from the ''{{w|Star Wars}}'' universe.
|-
|{{w|Gliese 581 e|e}} || {{w|Eternia}} Prime || A reference to the main planet of ''{{w|Masters of the Universe}}''.
|-
|{{w|Gliese 581 f|f}} || Taupe Mars || {{w|Kim Stanley Robinson|Kim Stanley Robinson's}} wrote the award-winning {{w|Mars trilogy}} (Red Mars, Green Mars, Blue Mars).
|-
|{{w|Gliese 581 g|g}} || Jelly Filled Planet || Possibly a reference to the conjecture that this tidally locked planet has an isolated habitable zone under the substellar point, akin to the pocket of jelly in a jelly doughnut.
|-
| rowspan=2 | {{w|Epsilon Eridani}} || {{w|Epsilon Eridani b|b}} || Skydot || {{w|Skynet_(Terminator)|Skynet}}, a computer system developed for the U.S. military, getting into service on August 4, 1997.
|-
|{{w|Epsilon Eridani c#Planet_c|c}} || Laser Noises || A {{w|Laser}} does not produce {{wNoise (electronics)|noises}}, it only works at a well defined frequency.
|-
| rowspan=2 | {{w|Gliese 176}} || {{w|Gliese 176 b|b}} || {{w|Fictional universe of Avatar|Pandora}} || The fictional moon in James Cameron's ''{{w|Avatar (film)|Avatar}}''. Also the Planet used in {{w|Borderlands (video game)| Borderlands Games}}.
|-
|[http://exoplanet.eu/catalog/gj_176_c/ c] || Pantera || Named for the {{w|Pantera|heavy metal band}}.
|-
| Kepler-61 || {{w|Kepler-61b|b}} || Goldenpalace.com || A Gambling Site.
|-
! colspan=4 | ...
|-
| style="white-space:nowrap;" rowspan=3 | {{w|Upsilon Andromedae}} || {{w|Upsilon Andromedae c|c}} || Stampy || The name of the elephant from the {{w|Simpsons}} episode, "Bart Gets an Elephant".
|-
|{{w|Upsilon Andromedae d|d}} || Moonchild || The name Bastian gives the Childlike Empress in {{w|The Neverending Story}}.
|-
|{{w|Upsilon Andromedae e|e}} || Ham Sphere || [http://www.hamsphere.com/ HamSphere] is a {{w|Amateur radio|Ham Radio}} simulator program. Ham radio uses designated radio frequencies for non-commercial exchange of messages and more.
|-
| rowspan=3 | {{w|82 G. Eridani|HD 20794}} || [http://exoplanet.eu/catalog/hd_20794_b/ b] || Cosmic Sands || style="font-family:'Comic Sans MS', 'Comic Sans';" | A {{w|pun}} on the name of the font {{w|Comic Sans}}. (See also: [[590|590: Papyrus]].)
|-
|[http://exoplanet.eu/catalog/hd_20794_c/ c] || Legoland || {{w|Legoland}} is a chain of {{w|Theme_park|Theme Parks}} owned by the {{w|Lego Group}} and run by British company {{w|Merlin Entertainments}}.
|-
|[http://exoplanet.eu/catalog/hd_20794_d/ d] || Planet with Arms || A reference to the early [http://www.thecolorsofmysoul.com/wp-content/uploads/2012/12/The-Hitchhikers-Guide-to-the-Galaxy.jpg covers] of {{w|Hitchhiker's Guide to the Galaxy}}?
|-
| {{w|HD 85512}} || {{w|HD 85512 b|b}} || Lax Morality ||
|-
| rowspan=6 | {{w|HD 40307}} || {{w|HD 40307 b|b}} || Good Planet ||
|-
|{{w|HD 40307 c|c}} || ProblemLand ||
|-
|{{w|HD 40307 d|d}} || Slickle ||
|-
|{{w|HD 40307 e|e}} || Spare Parts ||
|-
|{{w|HD 40307 f|f}} || New Jersey VI ||
|-
|{{w|HD 40307 g|g}} || How Do I Join the IAU || This implies that the user "got lost" on the IAU website and thought that the "planet name suggestion" input was for general queries.
|-
| rowspan=3 | {{w|Gliese 163}} || [http://exoplanet.eu/catalog/gj_163_b/ b] || Neil Tyson's Mustache || [http://en.wikipedia.org/wiki/Neil_deGrasse_Tyson Neil deGrasse Tyson] is a famous American astrophysicist and science communicator who does maintain a distinguished mustache.
|-
|{{w|Gliese 163 c|c}} || help@gmail.com ||
|-
|[http://exoplanet.eu/catalog/gj_163_d/ d] || Hair-Covered Planet || {{w|Hairy ball theorem}}, a well-known theorem of topology.
|-
| {{w|Pi Mensae}} || {{w|Pi Mensae b|b}} || Moon Holder ||
|-
| {{w|HD 189733}} || {{w|HD 189733 b|b}} || Permadeath || A well-characterized "{{w|Hot Jupiter}}" at a temperature range of 973 ± 33 K to 1,212 ± 11 K. A reference to the identical named situation especially occurring in RPGs and MMORPGs ({{w|Permanent death}}).
|-
| {{w|Kepler-22}} || {{w|Kepler-22 b|b}} || Blue Ivy || Blue Ivy Carter, daughter of musicians {{w|Beyoncé}} and {{w|Jay-Z}}.
|-
| Kepler-3284 || b || Blainsley ||
|-
| Kepler-3255 || b || Unicorn Thresher ||
|-
| Kepler-2418 || b || Spherical {{w|Discworld}} || A creation of British author {{w|Terry Pratchett|Sir Terry Pratchett}}, {{w|The Discworld}} is the fictional setting for his {{w|Discworld}} series of books and comprises of a large disc supported by four elephants themselves standing on top of a turtle flying through space.
|-
| Kepler-1686 || {{w|KOI-1686.01|b}} || style="white-space:nowrap;" | Emergency Backup Earth || This candidate planet has an {{w|Earth Similarity Index}} of 0.89, making it to one of the most habitable {{w|Kepler Object of Interest}} (KOI).
|-
| Kepler-3010 || b || Feeeoooooooop ||
|-
| Kepler-4742 || b || Liz ||
|}

==Transcript==
:August 2013:
:The International Astronomical Union decides to start naming exoplanets, and—for the first time ever—asks for suggestions from the general public.
:They immediately regret this decision.
:Cueball‏‎: Can't you filter out the worst ones?
:''The rightmost person'': This is '''''after''''' the filter!

{{comic discussion}}

[[Category:Comics featuring Cueball‏‎]]
[[Category:Comics featuring Megan]]
[[Category:Comics featuring Ponytail]]
[[Category:Astronomy]]
[[Category:Sex]]

explain xkcd - User contributions [en]

1308: Christmas Lights

1253: Exoplanet Names