IdeaWazaWiki - User contributions [en]

Gliese 581 d

2009-04-21T21:19:34Z

66.93.12.103:

{{Planetbox begin
| name = Gliese 581 d
}}
{{Planetbox image
| image = Gliese 581 d-v1.jpg
| caption = An artist's impression of Gliese 581 d and speculative moons.
}}
{{Planetbox star
| star = [[Gliese 581]]
| constell = [[Libra (constellation)|Libra]]
| RA = {{RA|15|19|26}}
| DEC = {{DEC|−07|43|20}}
| app_mag = 10.55
| dist_ly = 20.3 ± 0.3
| dist_pc = 6.2 ± 0.1
| class = M3V
}}
{{Planetbox orbit
| period = 83.6 ± 0.7<ref name="udry">{{cite journal|url=http://cdsads.u-strasbg.fr/cgi-bin/nph-bib_query?2007A%26A...469L..43U&db_key=AST&nosetcookie=1|title=The HARPS search for southern extra-solar planets. XI. Super-Earths (5 and 8 M<sub>⊕</sub>) in a 3-planet system|author=Udry, S.; Bonfils, X.; Delfosse, X.; Forveille, T.; Mayor, M.; Perrier, C.; Bouchy, F.; Lovis, C.; Pepe, F.; Queloz, D.; Bertaux, J.-L.|journal=[[Astronomy and Astrophysics]]|volume=469|issue=3|year=2007|pages=L43 – L47|doi=10.1051/0004-6361:20077612|accessdate=2008-08-18}}</ref>
| semimajor = 0.25<ref name="udry" />
| eccentricity = 0.20 ± 0.10<ref name="udry" />
| arg_peri = 295 ± 28<ref name="udry" />
| semi_amp = 2.52 ± 0.17<ref name="udry" />
| t_peri = 2,452,936.9 ± 9.2<ref name="udry" />
}}
{{Planetbox character
| minimum_mass_earth = 7.7<ref name="udry" />
}}
{{Planetbox discovery
| discovery_date = [[24 April]] [[2007]]
| discoverers = [[Stéphane Udry|Udry]] et al.
| discovery_method = [[Radial velocity]]
| discovery_site = {{flag|Chile}}
| discovery_status = Published<ref name=udry />
}}
{{Planetbox reference
| star=Gliese+581
| planet=d
}}
{{Planetbox end}}

'''Gliese 581 d''' ({{pron-en|ˈɡliːzə}}) is an [[extrasolar planet]] approximately 20 [[light-year]]s away in the [[constellation]] of [[Libra (constellation)|Libra]]. Because of its mass, the planet is classified as a [[super-Earth]] planet. In late April
2009 new observations by the original discovery team concluded that the planet is within the habitable zone where liquid water could exist.
== Discovery ==

The planet was discovered by the team of [[Stéphane Udry]] of the [[Geneva Observatory]] in [[Switzerland]] using the [[HARPS]] instrument on the [[European Southern Observatory]] 3.6 meter [[telescope]] in [[La Silla]], [[Chile]] on [[24 April]] [[2007]]. Udry's team employed the [[radial velocity]] technique, in which the size and [[mass]] of a [[planet]] are determined based on the small perturbations it induces in its parent star’s [[orbit]] via [[gravity]].<ref name=udry/>

The team is confident that the planet exists but recognizes that unlikely events could mimic its existence. They believe the issue will be settled by upcoming studies.

Dynamical simulations of the Gliese 581 system assuming that the orbits of the three planets are [[coplanarity|coplanar]] show that the system becomes unstable if its component masses are so high as to correspond to an overall inclination angle of 10° or less.<ref>{{cite journal|url=http://cdsads.u-strasbg.fr/cgi-bin/nph-bib_query?2008A%26A...479..277B&db_key=AST&nosetcookie=1|author=Beust, H. et al.|title=Dynamical evolution of the Gliese 581 planetary system|journal=[[Astronomy and Astrophysics]]|volume=479|issue=1|year=2008|pages=277–282|doi=10.1051/0004-6361:20078794|accessdate=2008-08-20}}</ref> For Gliese 581 d, the upper bound of its mass must be half that of 581 b; that is, 581 d's maximum is 44 Earth masses.<ref>Dividing the m sin i by "Sin(10/180 * PI)" on a radian-configured processor.</ref> At this mass it must be held together with a central heavy-element core like [[Saturn]] and maybe even [[HD 149026 b]].

== Climate and habitability ==

It was originally thought that Gliese 581 d orbits outside the theoretical [[habitable zone]] of its star. However, further studies released in April of 2009 confirmed that the planet is within the zone where liquid water could exist. According to Stephan Udry " d could be covered by a deep ocean, it is the first serious waterworld candidate."“Gliese 581 d is probably too massive to be made only of rocky material, but we can speculate that it is an icy planet that has migrated closer to the star,” .<ref>[http://www.space.com/scienceastronomy/070618_mm_gliese_581d.html SPACE.com - Hopes Dashed for Life on Distant Planet]</ref><ref>{{cite journal|url=http://cdsads.u-strasbg.fr/cgi-bin/nph-bib_query?2007A%26A...476.1365V&db_key=AST&nosetcookie=1|title=The Habitability of Super-Earths in Gliese 581|author=von Bloh, W.; Bounama, C.; Cuntz, M.; Franck, S.|journal=[[Astronomy & Astrophysics]]|volume=476|pages=1365 – 1371|doi=10.1051/0004-6361:20077939|accessdate=2008-08-18|year=2007}}</ref> Scientists originally believed that Gliese 581 d would be too cold for [[liquid]] [[water]] to exist, and therefore could not support [[life]] in forms as existing on Earth. However, since Earth's temperature would be about -18°C<ref>{{cite web|url=http://lwf.ncdc.noaa.gov/oa/climate/globalwarming.html#q1 |title=Global Warming Frequently Asked Questions |publisher=Lwf.ncdc.noaa.gov |date=2008-05-08 |accessdate=2009-01-18}}</ref> without any greenhouse gases, and due to a theorized [[greenhouse effect]] of Gliese 581 d, research now suggests that [[atmospheric]] conditions on the planet could create [[temperature]]s at which liquid water can exist, and therefore the planet may be capable of supporting life.<ref>http://arxiv.org/abs/0712.3219v4</ref><ref>{{cite web|url=http://www.centauri-dreams.org/?p=1625 |title=Centauri Dreams » Blog Archive » Gliese 581d: A Habitable World After All? |publisher=Centauri-dreams.org |date=2007-12-13 |accessdate=2009-01-18}}</ref><ref>{{cite web|author=Posted at 12:06 AM in Space Exploration |url=http://www.dailygalaxy.com/my_weblog/2007/06/another_super_e.html |title=New 'Super Earth 2' Discovered in Constellation Libra |publisher=Dailygalaxy.com |date=2007-06-15 |accessdate=2009-01-18}}</ref>

On 21 April 2009, [[European Organisation for Astronomical Research in the Southern Hemisphere|ESO]] announced, together with the discovery of [[Gliese 581 e]], that they had refined the models of Gliese 581 d's orbit, discovering it lay well within the habitable zone.<ref>{{cite web|url=http://www.eso.org/public/outreach/press-rel/pr-2009/pr-15-09.html|title=Lightest exoplanet yet discovered|publisher=eso.org|date=2009-04-21|accessdate=2009-04-21}}</ref>

== References ==
{{reflist|2}}

== External links ==

{{commonscat|Gliese 581}}

{{Gliese 581}}
{{Sky|15|19|26|-|07|43|20|20.3}}

[[Category:Extrasolar planets]]
[[Category:Libra constellation]]
[[Category:Super-Earths]]
[[Category:Terrestrial planets]]
[[Category:Exoplanets discovered in 2007]]

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Archive:Fanboy

2008-08-03T22:43:59Z

66.93.250.202:

{{Otheruses4}}

'''Fanboy''' (sometimes spelled '''fanboi''') is a term used to describe an individual who is devoted to a single subject in an emotional or fanatical manner, or to a single point of view within that subject, often to the point where it is considered an obsession.

The term is most commonly associated with adolescent and teenage males but can be applicable to any age or sex, and is mostly applied by others as a derogatory label.

==History==

According to the [[Merriam-Webster]] Collegiate Dictionary, the earliest known use of the term "fanboy" in an English-language publication dates to 1919.<ref name="mw">[http://www.merriam-webster.com/dictionary/fanboy fanboy. (2008)]. In Merriam-Webster Online Dictionary. Retrieved July 7, 2008.</ref>

In [[comic book]] culture, a 1982 reference is to the cover of the "Official Underground and Newave Comix Price Guide". On this cover page are sketched overweight, overzealous comic book collectors wearing T-shirts that state "Fanboys of America," who are describing the extreme measures they would go to, including moving to San Francisco, to preserve their comics.

Also published in 1982, a comic strip appeared in Jim Engel and Chuck Fiala's "Fandom Confidential" comic. In the strip, Jim and Chuck met comic artist/writer [[John Byrne]] and collapsed into "mindless paroxysms of adoration." The John Byrne character responded that they were "a couple of fanboys in bondage" (a play on words referring to a [[List of Monty Python's Flying Circus episodes#10. E. Henry Thripshaw.27s Disease|Monty Python sketch]] in which an Elizabethan era character reads what she claims to be a new Shakespeare work called "Gay Boys in Bondage". <ref>[http://www.byrnerobotics.com/FAQ/listing.asp?ID=7&T1=Miscellaneous+Questions#154 Byrne Robotics: FAQ]</ref> Another early use is in a smart-alec editorial reply by "[[Ambush Bug]]" to a letter in his comic in [[1985]].

By 1990 the term was being used in [[popular music]] and [[science fiction]] circles<ref>
[http://groups.google.com/groups/search?lr=&safe=off&num=10&q=fanboy&safe=off&qt_s=Search&as_drrb=b&as_mind=1&as_minm=1&as_miny=1981&as_maxd=1&as_maxm=1&as_maxy=1990 USENET use before 1990]
</ref>, and as electronic entertainment gained popularity, the term became increasingly applied to [[computer]]s and [[video game consoles]] - with people often developing an obsessive loyalty towards one platform or brand.

Current subjects of such obsessive loyalty include areas of: [[TV show]]s; [[film|movie]]s; [[music]]; [[anime]]; [[comic book]]s; [[car]]s; [[video game console]]s, [[video games]] and [[MMORPG]]s; and [[computer]] [[operating system]]s, [[computer Hardware|hardware]] and [[software]]—and more recently politics.
<ref>
[http://blog.wired.com/27bstroke6/2007/11/whos-nuttier-ap.html "Who's Nuttier, Apple Fanatics or Ron Paul Enthusiasts?", Wired Magazine]
</ref>
<ref>
[http://www.blogmaverick.com/2007/02/03/the-fanboy-culture/ "The Fanboy Culture", Mark Cuban, blogpost]
</ref>

"Fanboy" was added to the [[Merriam-Webster]] Collegiate Dictionary in 2008.<ref>[http://www.welt.de/english-news/article2186069/New_words_in_the_Merriam-Webster_dictionary_.html New words in the Merriam-Webster dictionary] [[Die Welt]] online, 7 July 2008</ref>

==Fangirl==
The term fangirl, while similar, often carries slightly different connotations - often applied to any enthusiastic female fan regardless of obsessive qualities or not, and is often used with overtones of "[[teenybopper]]". Depending on context, "fangirl" may be used or perceived as a derogatory label.

==Media==

Popular depictions of Fanboy stereotypes include the [[Comic Book Guy]] on ''[[The Simpsons]]'' and columnist [[Larry Groznic]] from the satirical newspaper ''[[The Onion]]''. In the songs of the fannish [[parody]] [[musician]] [[Luke Ski]], many characters proudly consider themselves ''fanboys.''

===Comic books===
*[[Sergio Aragonés]]' ''Fanboy''
*[[Galactic Storm]]'s ''Fanboy''

===Television===
*''[[The Simpsons]]''' [[Comic Book Guy]] refers to himself as a fanboy.
*''[[Freakazoid!|Freakazoid]]'''s [[freakazoid!#Other characters|Fan Boy]]

===Radio/podcasts===
*[[Fanboy Radio]]
*Fanboy Planet.com[http://www.fanboyplanet.com]

===Movies===
* [[Fanboys (2003 film)|''Fanboys'' (2003 film)]], a New Zealand short film
* [[Fanboys (2008 film)|''Fanboys'' (2008 film)]], an American comedy film

==See also==
* [[Addiction]]
* [[Cyberstalking]]
* [[Editor war]]
* [[Anorak (slang)|Anorak]]
* [[Astroturfing]]
* [[Otaku]]
* [[Obsession]]

==References==
{{reflist}}

==External links==
* [http://www.bruceongames.com/2008/02/17/fanboys/ A look at fanboys from the game industry perspective]
* [http://www.merriam-webster.com/dictionary/fanboy Fanboy at Merriam-Webster]
* [http://www.netjak.com/review.php/1013 Dissecting the Fanboy Mind] - A discussion of the fanboy behavior in regard to video games.
* [http://palgn.com.au/article.php?id=6463 The trial of the Fanboy] - A criticism of the fanboy concept and overusage of the term.

[[Category:Fandom]]
[[Category:Anime and manga terminology]]

[[de:Fan#Konsum]]
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