Mz3
Encyclopedia
Mz 3 is a young bipolar
planetary nebula
in the 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.
Mz 3 is a complex system composed of three nested pairs of bipolar lobes and an equatorial ellipse.
Its lobes all share the same axis of symmetry but each have very different morphologies and opening angles.
It is an unusual PN in that it is believed, by some researchers, to contain a symbiotic binary at its center.
Study suggests that the dense nebular gas at its center may have originated from a source different than that of its extended lobes. 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.
Mz 3 is often referred to as the Ant Nebula because it resembles the head and thorax
of a garden-variety ant
.
(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 H2 emission lines in the near-IR. The lack of H2 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).
The Ant Nebula is 8,000 light years away from Earth and it has a magnitude of 13.8
in 1922.
It was studied on July 20, 1997 by astronomer
s Bruce Balick (University of Washington
) and Vincent Icke (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.
Bipolar nebula
A bipolar nebula is a distinctive nebular formation characterized by an axially symmetric bi-lobed appearance.Many, but not all, planetary nebulae exhibit an observed bipolar structure...
planetary nebula
Planetary nebula
A planetary nebula is an emission nebula consisting of an expanding glowing shell of ionized gas ejected during the asymptotic giant branch phase of certain types of stars late in their life...
in the constellation Norma
Norma (constellation)
Norma is a small and inconspicuous constellation in the southern hemisphere between Scorpius and Centaurus. Its name is Latin for normal, referring to a right angle, and is variously considered to represent a rule, a carpenter's square, a set square or a level....
that is composed of a bright core and four distinct high-velocity outflows that have been named lobes, columns, rays, and chakram
Chakram
The chakram , sometimes called a war quoit, is a throwing weapon from India. Its shape is of a flat metal hoop with a sharp outer edge from in diameter...
. 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.
Mz 3 is a complex system composed of three nested pairs of bipolar lobes and an equatorial ellipse.
Its lobes all share the same axis of symmetry but each have very different morphologies and opening angles.
It is an unusual PN in that it is believed, by some researchers, to contain a symbiotic binary at its center.
Study suggests that the dense nebular gas at its center may have originated from a source different than that of its extended lobes. 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
White dwarf
A white dwarf, also called a degenerate dwarf, is a small star composed mostly of electron-degenerate matter. They are very dense; a white dwarf's mass is comparable to that of the Sun and its volume is comparable to that of the Earth. Its faint luminosity comes from the emission of stored...
that provides ionizing photons for the PN.
Mz 3 is often referred to as the Ant Nebula because it resembles the head and thorax
Thorax
The thorax is a division of an animal's body that lies between the head and the abdomen.-In tetrapods:...
of a garden-variety ant
Ant
Ants are social insects of the family Formicidae and, along with the related wasps and bees, belong to the order Hymenoptera. Ants evolved from wasp-like ancestors in the mid-Cretaceous period between 110 and 130 million years ago and diversified after the rise of flowering plants. More than...
.
Characteristics
Mz 3 is radially expanding at a rate of about 50 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 Butterfly NebulaPlanetary Nebula M2-9
Minkowski 2-9, abbreviated M2-9, is a planetary nebula that was discovered by Rudolph Minkowski in 1947. It is located about 2,100 light-years away from Earth in the direction of the constellation Ophiuchus...
(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 H2 emission lines in the near-IR. The lack of H2 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).
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.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 MenzelDonald Howard Menzel
Donald Howard Menzel was one of the first theoretical astronomers and astrophysicists in the US. He discovered the physical properties of the solar chromosphere, the chemistry of stars, the atmosphere of Mars, and the nature of gaseous neblulae.-Biography:Born in Florence, Colorado in 1901 and...
in 1922.
It was studied on July 20, 1997 by astronomer
Astronomer
An astronomer is a scientist who studies celestial bodies such as planets, stars and galaxies.Historically, astronomy was more concerned with the classification and description of phenomena in the sky, while astrophysics attempted to explain these phenomena and the differences between them using...
s Bruce Balick (University of Washington
University of Washington
University of Washington is a public research university, founded in 1861 in Seattle, Washington, United States. The UW is the largest university in the Northwest and the oldest public university on the West Coast. The university has three campuses, with its largest campus in the University...
) and Vincent Icke (Leiden University
Leiden University
Leiden University , located in the city of Leiden, is the oldest university in the Netherlands. The university was founded in 1575 by William, Prince of Orange, leader of the Dutch Revolt in the Eighty Years' War. The royal Dutch House of Orange-Nassau and Leiden University still have a close...
) on observations done with the Hubble Space Telescope
Hubble Space Telescope
The Hubble Space Telescope is a space telescope that was carried into orbit by a Space Shuttle in 1990 and remains in operation. A 2.4 meter aperture telescope in low Earth orbit, Hubble's four main instruments observe in the near ultraviolet, visible, and near infrared...
. The telescope was later used on June 30, 1998 by Raghvendra Sahai and John Trauger of the Jet Propulsion Laboratory
Jet Propulsion Laboratory
Jet Propulsion Laboratory is a federally funded research and development center and NASA field center located in the San Gabriel Valley area of Los Angeles County, California, United States. The facility is headquartered in the city of Pasadena on the border of La Cañada Flintridge and Pasadena...
to picture the PN.
External links
- NASA APOD - Planetary Nebula Mz 3: The Ant Nebula
- STScI. Astro-Entomology? Ant-like Space Structure Previews Death of Our Sun. Press release: Space Telescope Science Institute. February 1, 2001.