View source for Mz 3

{{Short description|Planetary nebula in the constellation Norma}}
{{ Planetary nebula |
| image = [[Image:Ant Nebula.jpg|250px]]
|caption=The Ant Nebula taken by [[Hubble Space Telescope]] in 2008
| name = Ant Nebula
| type = Planetary
| epoch = [[J2000]]
| ra = {{RA|16|17|13.392}}<ref name="simbad">{{Harvnb|SIMBAD|2006}}</ref>
| dec = {{DEC|-51|59|10.31}}<ref name="simbad" />
| dist_ly = [[1 E19 m|~8,000]] [[light-year|ly]] (~2,500 [[parsec|pc]])<ref name="Smith2003" />
| appmag_v = 13.8<ref name="pn" />
| size_v = >50{{pprime}} × 12{{pprime}}<ref name="Smith2003" />
| constellation = [[Norma (constellation)|Norma]]
| radius_ly = 1.0 ly{{Ref_label|A|a|none}}
| absmag_v = 1.8{{Ref_label|B|b|none}}
| notes = Three nested pairs of bipolar lobes
| names = ESO 225-9,<ref name="simbad" /> Ant Nebula,<ref name="simbad" /><br/>
Chamber of Horrors{{Ref_label|C|c|none}}
}}

'''Mz 3''' ('''Menzel 3''') is a young [[bipolar nebula|bipolar]] [[planetary nebula]] (PN) in the constellation [[Norma (constellation)|Norma]] that is composed of a bright core and four distinct high-velocity outflows that have been named lobes, columns, rays, and [[chakram]].  These nebulosities are described as: two spherical bipolar lobes, two outer large filamentary [[hour-glass]] shaped columns, two cone shaped rays, and a planar radially expanding, elliptically shaped chakram.<ref name="Santanderetal2004">{{Harvnb|Santander-García|Corradi|Balick|Mampaso|2004}}</ref><ref name="Zhangeta2006">{{Harvnb|Zhang|Liu|2006}}</ref>
Mz 3 is a complex system composed of three nested pairs of bipolar lobes and an equatorial ellipse.<ref name="Guerreroeta2004">{{Harvnb|Guerrero|Chu|Miranda|2004}}</ref>
Its lobes all share the same axis of symmetry but each have very different morphologies and opening angles.<ref name="Guerreroeta2004" />
It is an unusual [[Planetary nebula|PN]] in that it is believed, by some researchers, to contain a symbiotic binary at its center.<ref name="Zhangeta2006" />
One study suggests that the dense nebular gas at its center may have originated from a source different from that of its extended lobes.<ref name="Zhangeta2006" />   The working model to explain this hypothesizes that this PN is composed of a giant companion that caused a central dense gas region to form, and a [[white dwarf]] that provides ionizing photons for the PN.<ref name="Zhangeta2006" />

Mz 3 is often referred to as the '''Ant Nebula''' because it resembles the head and [[thorax]] of a garden-variety [[ant]].

==Characteristics==
Mz 3 is radially expanding at a rate of about 50&nbsp;km/s and has its polar axis oriented at an angle of around 30° from the plane of the sky (Lopez & Meaburn 1983; Meaburn & Walsh 1985).  It is sometimes compared to the more extensively studied [[Planetary Nebula M2-9|Butterfly Nebula]] (M 2-9), and it is quite likely that both have a similar evolutionary history.  They both have point-like bright nuclei, are narrow-waisted bipolar nebulae, and share surprisingly similar spatially dependent spectra. Because of their similarity, their differences are noteworthy.  Their greatest difference is probably in their [[near infrared]] emissions.  Mz 3 has no trace of molecular hydrogen emission, whereas the M 2-9 has prominent H<sub>2</sub> emission lines in the near-IR.  The lack of H<sub>2</sub> emissions from Mz 3 is unusual given the strong correlation between such emissions and bipolar structures of PN.  Additionally, the polar lobes of Mz 3 are more mottled and rounded as compared to M 2-9. Finally, Mz 3 is not known to evidence temporal variability in its polar lobes as is found in M 2-9 (Doyle et al. 2000). {{Harv|Smith|2003}}

The [[Herschel Space Observatory]] has detected [[laser]] light emissions from the nebula -- specifically, hydrogen recombination line laser emissions.  This confirms the presence of a [[white dwarf]] with a binary companion at the heart of the nebula.<ref>{{cite web|url=http://www.esa.int/Our_Activities/Space_Science/Herschel/A_space_ant_fires_its_lasers|title=A space ant fires its lasers|last=esa|website=European Space Agency}}</ref>

===Chakram===
Of the morphological features of Mz 3, one of the most unusual and odd is the chakram (first noticed in 2004), a faint, large, limb brightened ellipse that appears to have its center on the PN's nucleus.  While the plane of the ellipse is near the other feature's shared reflection symmetry plane, it is definitely offset.  This structure's kinematics are the only such ones known among studied PN.  Unlike all the other Mz 3 structures, there is no increase of velocity as the radial offset from the nucleus increases.  Consequently, this must not be a simple equatorial flow despite the fact that its motion appears to be strictly radial (that is, there is no indication of rotation which would suggest that this feature is dynamically stable).  All the kinematic properties of the ellipse are symmetric and very ordered relative to the nucleus, consistent with all the other Mz 3 features.  Therefore, the ellipse must be historically linked to the evolution of the central star. {{Harv|Santander-García|Corradi|Balick|Mampaso|2004}}

The Ant Nebula is 8,000 light years away from Earth and it has a magnitude of 13.8.

==History==
Mz 3 was discovered by [[Donald Howard Menzel]] in 1922.<ref name="Smith2003">{{Harvnb|Smith|2003}}</ref> {{Harvnb|Menzel|1922}}

It was studied on July 20, 1997 by [[astronomer]]s {{ill|Bruce Balick|de}} ([[University of Washington]]) and {{ill|Vincent Icke|nl}} ([[Leiden University]]) on observations done with the [[Hubble Space Telescope]].  The telescope was later used on June 30, 1998 by [[Raghvendra Sahai]] and [[John Trauger]] of the [[Jet Propulsion Laboratory]] to picture the PN.

== Notes ==
{{refbegin}}

<ol type="a">
<li>{{Note_label|A|a|none}}8,000 ly distance × sin( >50{{pprime}} diameter_angle / 2 ) = 1.0 ly. radius</li>
<li>{{Note_label|B|b|none}}13.8<ref name="pn">{{Harvnb|Gottlieb|Wallace|2005}}</ref> apparent magnitude – 5 * (log<sub>10</sub>(2,500 pc distance) – 1) = 1.8 absolute magnitude</li>
<li>{{Note_label|C|c|none}}Mz 3 has several components with varying degrees of collimation.  It also has an unusual spectrum.  Together, these entitle it to the nickname of "The Chamber of Horrors" of planetary nebulae as given by Evans in 1959.<ref name="Smith2003" /><ref name="Santanderetal2004" /></li>
</ol>
{{refend}}
{{reflist}}

==References==
{{refbegin}}
* {{citation
 | last1 = Gottlieb
 | first1 = Steve
 | last2 = Wallace
 | first2 = Kent
 | title = Results for Mz 3
 | journal = Doug Snyder's Planetary Nebulae Web Site
 | date = July 15, 2005
 | publisher = Doug Snyder
 | url = http://www.blackskies.org/reports05.htm#Mz3
 | access-date = January 10, 2007
 | archive-date = February 6, 2012
 | archive-url = https://web.archive.org/web/20120206042522/http://www.blackskies.org/reports05.htm#Mz3
 | url-status = dead
 }}
* {{citation
 | last1 = Guerrero
 | first1 = Martín A.
 | last2 = Chu
 | first2 = You-Hua
 | last3 = Miranda
 | first3 = Luis F.
 | title = Menzel 3: a Multipolar Nebula in the Making
 | journal = The Astronomical Journal
 | date = 2004
 | volume = 128
 | issue = 4
 | pages = 1694–1704
 | bibcode = 2004AJ....128.1694G
 | doi = 10.1086/423909
|arxiv = astro-ph/0407030 | s2cid = 17243082
 }}
* {{citation
 | last1 = Menzel
 | first1 = D. N.
 | author1-link = Donald Howard Menzel
 | title = Five new planetary nebulae
 | journal = Harvard Bull.
 | date = 1922
 | volume = 177
 | bibcode = 1922BHarO.777....0M
 | pages = 0
}}
* {{citation
 | last1 = Santander-García
 | first1 = M.
 | last2 = Corradi
 | first2 = R. L. M.
 | last3 = Balick
 | first3 = B.
 | last4 = Mampaso
 | first4 = A.
 | title = Menzel 3: Dissecting the ant
 | journal = Astronomy and Astrophysics
 | date = 2004
 | volume = 426
 | issue = 1
 | pages = 185–194
 | bibcode = 2004A&A...426..185S
 | doi = 10.1051/0004-6361:20041147
|arxiv = astro-ph/0406551 | s2cid = 2203000
 }}
* {{citation
 | last1 = SIMBAD
 | title = Results for PN Mz 3
 | author1-link = SIMBAD
 | date = December 22, 2006
 | publisher = SIMBAD, Centre de Données Astronomiques de Strasbourg
 | url = http://simbad.u-strasbg.fr/simbad/sim-id?protocol=html&Ident=PN+Mz+3
 }}
* {{citation
 | last1 = Smith
 | first1 = Nathan
 | title = Spatial distribution of near-infrared and optical emission properties in the bipolar nebula Menzel 3
 | journal = Monthly Notices of the Royal Astronomical Society
 | date = 2003
 | volume = 342
 | issue = 2
 | pages = 383–398
 | bibcode = 2003MNRAS.342..383S
 | doi = 10.1046/j.1365-8711.2003.06557.x
| doi-access = free
 }}
* {{citation
 | last1 = Zhang
 | first1 = Y.
 | last2 = Liu
 | first2 = X.-W.
 | title = The Fe/Ni ratio in the Ant Nebula Mz 3
 | series= Planetary Nebulae in our Galaxy and Beyond, Proceedings of the International Astronomical Union, Symposium #234
 | editor=Ian F. Corbett.
 | location= Cambridge, MA
 | publisher=Cambridge University Press
 | date = 2006
 | pages = 547–548
 | bibcode = 2006IAUS..234..547Z
 | issue = S234
 | doi = 10.1017/S1743921306004170
 | journal = Proceedings of the International Astronomical Union
 | volume = 2
 |arxiv = astro-ph/0605180 | s2cid = 119517482
 }}
{{refend}}

==External links==
* {{commonscat-inline}}
* {{APOD |date=5 February 2001 |title=Planetary Nebula Mz 3: The Ant Nebula}}
* STScI. [http://hubblesite.org/newscenter/newsdesk/archive/releases/2001/05/ Astro-Entomology? Ant-like Space Structure Previews Death of Our Sun]. Press release: ''Space Telescope Science Institute''. February 1, 2001.


{{sky|16|17|13.35|-|51|59|10.4|8000}}
{{Norma (constellation)|state=collapsed}}


{{DEFAULTSORT:Mz 3}}
[[Category:Planetary nebulae]]
[[Category:Norma (constellation)]]
[[Category:Astronomical objects discovered in 1922|?]]