NGC 3079

NGC 3079 is a barred spiral galaxy about 50 million light-years away, and located in the constellation Ursa Major. A prominent feature of this galaxy is the "bubble" forming in the very center (see picture below). The Supermassive black hole at the core has a mass of 2.4+2.4
−1.2
×106 M
.[3]

NGC 3079
NGC 3079
A Hubble Space Telescope (HST) image of NGC 3079.
Observation data (J2000 epoch)
ConstellationUrsa Major
Right ascension 10h 01m 57.8s[1]
Declination+55° 40′ 47″[1]
Redshift1116 ± 1 km/s[1]
Distance50 Mly[2]
Apparent magnitude (V)11.5[1]
Characteristics
TypeSB(s)c[1]
Apparent size (V)7′.9 × 1′.4[1]
Other designations
UGC 5387,[1] PGC 29050[1]

Center Bubble

The bubble forming in the center of NGC 3079 is believed to be about 3000 light-years wide and to rise more than 3500 light-years above the disc of the galaxy. It is speculated that the bubble is being formed by particles streaming at high speeds, which were in turn caused by a large burst of star formation. This current bubble is thought to have been created about one million years ago, and computer modeling suggests that there is an ongoing cycle of forming bubbles, with a new bubble forming approximately every 10 million years. Galaxies that contain an active Supermassive black hole are known as Seyfert galaxies.

NGC 3079 (captured by the Hubble Space Telescope)
Hubble space telescope, (visible light) Seyfert galaxy NGC 3079. This image shows the lumpy bubble of hot gas located at the center of the NGC 3079 galaxy's disk

See also

External links

References

  1. ^ a b c d e f g h "NASA/IPAC Extragalactic Database". Results for NGC 3079. Retrieved 2006-11-25.
  2. ^ "Burst of Star Formation Drives Bubble in Galaxy's Core - Fast Facts". Retrieved 2007-10-06.
  3. ^ Graham, Alister W. (November 2008), "Populating the Galaxy Velocity Dispersion - Supermassive Black Hole Mass Diagram: A Catalogue of (Mbh, σ) Values", Publications of the Astronomical Society of Australia, 25 (4): 167–175, arXiv:0807.2549, Bibcode:2008PASA...25..167G, doi:10.1071/AS08013.
Black Eye Galaxy

The Black Eye Galaxy (also called Evil Eye Galaxy and designated Messier 64, M64, or NGC 4826) is a relatively isolated spiral galaxy located 17 million light years away in the northern constellation of Coma Berenices. It was discovered by Edward Pigott in March 1779, and independently by Johann Elert Bode in April of the same year, as well as by Charles Messier in 1780. A dark band of absorbing dust in front of the galaxy's bright nucleus gave rise to its nicknames of the "Black Eye" or "Evil Eye" galaxy. M64 is well known among amateur astronomers because of its appearance in small telescopes.

This galaxy is inclined 60° to the line-of-sight and has a position angle of 112°. At the distance of this galaxy, it has a linear scale of 65 ly (20 pc) per arcsecond. The morphological classification of NGC 4826 in the De Vaucouleurs system is (R)SA(rs)ab, where the '(R)' indicates an outer ring-like structure, 'SA' denotes a non-barred spiral, '(rs)' means a transitional inner ring/spiral structure, and 'ab' says the spiral arms are fairly tightly wound. Ann et al. (2015) gave it a class of SABa, suggesting a weakly-barred spiral galaxy with tightly wound arms.

M64 is a type 2 Seyfert galaxy with an HII/LINER nucleus. The central region is a weak source of radio emission. A soft X-ray source has been detected at the nucleus, which is most likely coming from the circumnuclear region rather than directly from an active galactic nucleus. There is an inner disk of molecular gas that is truncated at a radius of 2,300 ly (700 pc). At present, the non-rotational motions of this disk do not significantly feed the core, but the disk does produce a vigorous rate of star formation. There is also evidence of a recent large inflow of mass.The interstellar medium of Messier 64 consists of two counter-rotating disks that are approximately equal in mass. The inner disk contains the prominent dust lanes of the galaxy. The stellar population of the galaxy exhibits no measurable counter-rotation. Possible formation scenarios include a merger with a gas-rich satellite galaxy in a retrograde orbit, or the continued accretion of gas clouds from the intergalactic medium. It has a diameter of 54,000 light-years (17 kpc).

Herschel 400 Catalogue

The Herschel 400 catalogue is a subset of William Herschel's original Catalogue of Nebulae and Clusters of Stars, selected by Brenda F. Guzman (Branchett), Lydel Guzman, Paul Jones, James Morrison, Peggy Taylor and Sara Saey of the Ancient City Astronomy Club in St. Augustine, Florida, United States c. 1980. They decided to generate the list after reading a letter published in Sky & Telescope by James Mullaney of Pittsburgh, Pennsylvania, USA.In this letter Mr. Mullaney suggested that William Herschel's original catalogue of 2,500 objects would be an excellent basis for deep sky object selection for amateur astronomers looking for a challenge after completing the Messier Catalogue.

The Herschel 400 is a subset of John Herschel's General Catalogue of Nebulae and Clusters published in 1864 of 5,000 objects, and hence also of the New General Catalogue.

The catalogue forms the basis of the Astronomical League's Herschel 400 club. In 1997, another subset of 400 Herschel objects was selected by the Rose City Astronomers of Portland, Oregon as the Herschel II list, which forms the basis of the Astronomical League's Herschel II Program.

Interstellar formaldehyde

Interstellar formaldehyde (a topic relevant to astrochemistry) was first discovered in 1969 by L. Snyder et al. using the National Radio Astronomy Observatory. Formaldehyde (H2CO) was detected by means of the 111 - 110 ground state rotational transition at 4830 MHz. On 11 August 2014, astronomers released studies, using the Atacama Large Millimeter/Submillimeter Array (ALMA) for the first time, that detailed the distribution of HCN, HNC, H2CO, and dust inside the comae of comets C/2012 F6 (Lemmon) and C/2012 S1 (ISON).

List of black holes

This is a list of black holes (and stars considered probable candidates) organized by size (including black holes of undetermined mass); some items in this list are galaxies or star clusters that are believed to be organized around a black hole. Messier and New General Catalogue designations are given where possible.

List of spiral galaxies

A spiral galaxy is a type of galaxy characterized by a central bulge of old Population II stars surrounded by a rotating disc of younger Population I stars. A spiral galaxy maintains its spirals arms due to density wave theory.

NGC 3859

NGC 3859 is a spiral galaxy located about 295 million light-years away in the constellation Leo. It was discovered by astronomer Édouard Stephan on March 23, 1884. The galaxy is a member of the Leo Cluster.

Seyfert galaxy

Seyfert galaxies are one of the two largest groups of active galaxies, along with quasars. They have quasar-like nuclei (very luminous, distant and bright sources of electromagnetic radiation) with very high surface brightnesses whose spectra reveal strong, high-ionisation emission lines, but unlike quasars, their host galaxies are clearly detectable.Seyfert galaxies account for about 10% of all galaxies and are some of the most intensely studied objects in astronomy, as they are thought to be powered by the same phenomena that occur in quasars, although they are closer and less luminous than quasars. These galaxies have supermassive black holes at their centers which are surrounded by accretion discs of in-falling material. The accretion discs are believed to be the source of the observed ultraviolet radiation. Ultraviolet emission and absorption lines provide the best diagnostics for the composition of the surrounding material.Seen in visible light, most Seyfert galaxies look like normal spiral galaxies, but when studied under other wavelengths, it becomes clear that the luminosity of their cores is of comparable intensity to the luminosity of whole galaxies the size of the Milky Way.Seyfert galaxies are named after Carl Seyfert, who first described this class in 1943.

Twin Quasar

The Twin Quasar (also known as Twin QSO, Double Quasar, SBS 0957+561, TXS 0957+561, Q0957+561 or QSO 0957+561 A/B), was discovered in 1979 and was the first identified gravitationally lensed object. It is a quasar that appears as two images, a result from gravitational lensing caused by the galaxy YGKOW G1 that is located in the line of sight between Earth and the quasar.

Ursa Major

Ursa Major (; also known as the Great Bear) is a constellation in the northern sky, whose associated mythology likely dates back into prehistory. Its Latin name means "greater (or larger) she-bear", standing as a reference to and in direct contrast with nearby Ursa Minor, the lesser bear. In antiquity, it was one of the original 48 constellations listed by Ptolemy (2nd century AD), and is now the third largest constellation of the 88 modern constellations.

Ursa Major is primarily known from the asterism of its main seven relatively bright stars comprising the "Big Dipper", "the Wagon", "Charles's Wain" or "the Plough" (among others), with its stellar configuration mimicking the shape of the "Little Dipper".

The general constellation outline often significantly features in numerous world cultures, and frequently is used as a symbol of the north. e.g. as the flag of Alaska. Also the asterism's two brightest stars, named Dubhe and Merak (α Ursae Majoris and β Ursae Majoris), can be used as the navigational pointer towards the place of the current northern pole star, Polaris in Ursa Minor.

Ursa Major is visible throughout the year from most of the northern hemisphere, and appears circumpolar above the mid-northern latitudes. From southern temperate latitudes, the main asterism is invisible, but the southern parts of the constellation can still be viewed.

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