View source for IC 418

{{Short description|Planetary nebula in the constellation Lepus}}
{{Infobox planetary nebula
| image = [[Image:Spirograph Nebula - Hubble 1999.jpg|250px]]
| name = [[Index Catalogue|IC]] 418
| type = Planetary
| epoch = [[J2000]]
| ra = {{RA|05|27|28.2037}}<ref name="simbad">{{cite simbad
  | title=IC 418
  | access-date=2006-12-22}}</ref>
| dec = {{DEC|-12|41|50.265}}<ref name="simbad" />
| dist_ly = 3.6 ± 1.0 [[light year|kly]] (1100 ± 300 [[parsec|pc]])<ref name="ads">{{cite journal
  | title=Expansion Parallax of the Planetary Nebula IC 418
  | volume=138
 | pages=46–49
 | journal=The Astronomical Journal
  | bibcode=2009AJ....138...46G
  | arxiv=0905.0021
  | doi=10.1088/0004-6256/138/1/46
  | year=2009
 | last1=Guzmán
 | first1=Lizette
 | last2=Loinard
 | first2=Laurent
 | last3=Gómez
 | first3=Yolanda
 | last4=Morisset
 | first4=Christophe
 | issue=1
 | s2cid=17714722
 }}</ref>
| appmag_v = 9.6<ref name="simbad" />
| size_v = 3.5″x5.5"/11"x14"/150"/220"x250"<ref>{{cite journal
 | first=G. | last=Ramos-Larios
 |display-authors=etal
 | title=Discovery of multiple shells around the planetary nebula IC 418
 | journal=[[Monthly Notices of the Royal Astronomical Society]]
 | date=2012 | volume=423
 | issue=4 | pages=3753–3760
 | bibcode=2012MNRAS.423.3753R
 | doi=10.1111/j.1365-2966.2012.21165.x | doi-access=free
 |arxiv = 1204.5816| s2cid=118442646
 }}</ref>
| constellation = [[Lepus (constellation)|Lepus]]
| radius_ly = 0.15
| absmag_v = -
| notes = -
| names = Spirograph Nebula
|caption=A false color image of IC 418 (the spirograph nebula).}}
'''IC 418''', also known as the '''Spirograph Nebula''', is a [[planetary nebula]] located in the [[constellation]] of [[Lepus (constellation)|Lepus]] about 3,600 [[Light-year|ly]] away from [[Earth]]. It spans 0.3 [[light-years]] across. The central [[star]] of the planetary nebula, '''HD 35914''', is an [[O-type star]] with a [[Stellar classification|spectral type]] of O7fp.<ref>{{cite journal |last1=González-Santamaría |first1=I. |last2=Manteiga |first2=M. |last3=Manchado |first3=A. |last4=Ulla |first4=A. |last5=Dafonte |first5=C. |last6=López Varela |first6=P. |year=2021 |title=Planetary nebulae in Gaia EDR3: Central star identification, properties, and binarity |journal=Astronomy & Astrophysics |volume=656 |pages=A51 |arxiv=2109.12114 |bibcode=2021A&A...656A..51G |doi=10.1051/0004-6361/202141916 |s2cid=237940344}}</ref> The [[nebula]] formed a few thousand years ago during the star's last stages of its [[red giant]] phase. Material from the star's outer layers was ejected from the star into the surrounding space. The nebula's glow is caused by the central star's [[Ultraviolet|ultraviolet radiation]] interacting with the gas.<ref>{{Cite web |title=Spirograph Nebula (IC 418) |url=https://www.esa.int/Science_Exploration/Space_Science/Extreme_space/Spirograph_Nebula_IC_418 |access-date=2023-11-26 |website=www.esa.int |language=en}}</ref>

The nebula gets its colors from the different [[Chemical element|chemical elements]] inside the nebula. The red color is [[nitrogen]] (the coldest gas in the nebula), the green is [[hydrogen]] and the traces of blue are the ionized [[oxygen]] gas (the hottest gas in the [[nebula]] due to its proximity to the central star).<ref>{{Cite web |title=Hubble's Spirograph - NASA Science |url=https://science.nasa.gov/missions/hubble/hubbles-spirograph/ |access-date=2023-11-26 |website=science.nasa.gov |language=en}}</ref>

==Naming==
The name derives from the intricate pattern of the [[nebula]], which resembles a pattern which can be created using the [[Spirograph]], a toy that produces [[geometric pattern]]s (specifically, [[hypotrochoid]]s and [[epitrochoid]]s) on paper. The origin of the Spirograph pattern is unknown.<ref>{{Cite web |last=information@eso.org |title=The Spirograph Nebula |url=https://www.spacetelescope.org/images/opo0028a/ |access-date=2023-11-26 |website=www.spacetelescope.org |language=en}}</ref>

==References==
{{Reflist}}

==External links==
*{{commonscat-inline}}
*[http://hubblesite.org/newscenter/newsdesk/archive/releases/2000/28/image/a The Spirograph Nebula (IC 418) - STScI Press Release]
*[[Astronomy Picture of the Day]] - [http://apod.nasa.gov/apod/ap100411.html IC 418: The Spirograph Nebula] - 2010 April 11
{{Lepus (constellation)}}
{{DEFAULTSORT:Ic 418}}
[[Category:Planetary nebulae|IC 0418]]
[[Category:Lepus (constellation)|IC 0418]]
[[Category:IC objects|0418]]
[[Category:O-type stars]]

{{nebula-stub}}