by neufer » Fri Oct 15, 2021 3:08 pm
https://en.wikipedia.org/wiki/NGC_289 wrote:
<<NGC 289 is a spiral galaxy in the southern constellation of Sculptor, located at a distance of 76 megalight-years from the Milky Way. It was discovered on September 27, 1834 by John Herschel. The compiler of the New General Catalogue, John Louis Emil Dreyer noted that NGC 289 was "pretty bright, large, extended, between 2 considerably bright stars". The plane of the galaxy is inclined by an angle of 45° to the line of sight from the Earth.
This is a
Type II Seyfert galaxy with an active galactic nucleus. A dust lane is seen crossing the nucleus, and there are indications of recent starburst activity nearby. NGC 289 is a giant, gas-rich, low surface brightness galaxy with a small bulge at the nucleus, a small central bar, and two inner spiral arms. These arms split into multiple parts as they extend into the outer disk. The galaxy has a dark matter halo that has an estimated 3.5 times the mass of the gaseous and stellar components. There is a dwarf elliptical companion to the north of the galaxy, designated Arp 1981, that may be having a perturbing influence.>>
https://en.wikipedia.org/wiki/289_Nenetta wrote:
<<289 Nenetta is a typical A-type asteroid. It was discovered by Auguste Charlois on 10 March 1890 in Nice, France. The spectrum of 289 Nenetta reveals the strong presence of the mineral Olivine, a relative rarity in the asteroid belt. The mineral olivine is a magnesium iron silicate with the chemical formula (Mg
2+, Fe
2+)
2SiO
4. The primary component of the Earth's upper mantle, it is a common mineral in Earth's subsurface, but weathers quickly on the surface. For this reason, olivine has been proposed as a good candidate for accelerated weathering to sequester carbon dioxide from the Earth's oceans and atmosphere, as part of climate change mitigation.
Mg-rich olivine has also been discovered in meteorites, on the Moon and Mars, falling into infant stars, as well as on asteroid
25143 Itokawa. Such meteorites include chondrites, collections of debris from the early Solar System; and pallasites, mixes of iron-nickel and olivine. The rare A-type asteroids are suspected to have a surface dominated by olivine. The spectral signature of olivine has been seen in the dust disks around young stars. The tails of comets (which formed from the dust disk around the young Sun) often have the spectral signature of olivine, and the presence of olivine was verified in samples of a comet from the Stardust spacecraft in 2006. Comet-like (magnesium-rich) olivine has also been detected in the planetesimal belt around the star Beta Pictoris.>>
[quote=https://en.wikipedia.org/wiki/NGC_289]
[float=left][img3=Hubble Space Telescope image of NGC 289]https://upload.wikimedia.org/wikipedia/commons/e/e8/Ngc289hst.jpg[/img3][/float]
<<NGC 289 is a spiral galaxy in the southern constellation of Sculptor, located at a distance of 76 megalight-years from the Milky Way. It was discovered on September 27, 1834 by John Herschel. The compiler of the New General Catalogue, John Louis Emil Dreyer noted that NGC 289 was "pretty bright, large, extended, between 2 considerably bright stars". The plane of the galaxy is inclined by an angle of 45° to the line of sight from the Earth.
This is a [url=https://en.wikipedia.org/wiki/Seyfert_galaxy#Type_II_Seyfert_galaxies]Type II Seyfert galaxy[/url] with an active galactic nucleus. A dust lane is seen crossing the nucleus, and there are indications of recent starburst activity nearby. NGC 289 is a giant, gas-rich, low surface brightness galaxy with a small bulge at the nucleus, a small central bar, and two inner spiral arms. These arms split into multiple parts as they extend into the outer disk. The galaxy has a dark matter halo that has an estimated 3.5 times the mass of the gaseous and stellar components. There is a dwarf elliptical companion to the north of the galaxy, designated Arp 1981, that may be having a perturbing influence.>>[/quote][quote=https://en.wikipedia.org/wiki/289_Nenetta]
[float=left][img3=Olivine basalt from the Moon, collected in 1971 by the crew of Apollo 15]https://upload.wikimedia.org/wikipedia/commons/thumb/2/29/Lunar_Olivine_Basalt_15555_from_Apollo_15_in_National_Museum_of_Natural_History.jpg/1104px-Lunar_Olivine_Basalt_15555_from_Apollo_15_in_National_Museum_of_Natural_History.jpg[/img3][/float]
<<289 Nenetta is a typical A-type asteroid. It was discovered by Auguste Charlois on 10 March 1890 in Nice, France. The spectrum of 289 Nenetta reveals the strong presence of the mineral Olivine, a relative rarity in the asteroid belt. The mineral olivine is a magnesium iron silicate with the chemical formula (Mg[sup]2+[/sup], Fe[sup]2+[/sup])[sub]2[/sub]SiO[sub]4[/sub]. The primary component of the Earth's upper mantle, it is a common mineral in Earth's subsurface, but weathers quickly on the surface. For this reason, olivine has been proposed as a good candidate for accelerated weathering to sequester carbon dioxide from the Earth's oceans and atmosphere, as part of climate change mitigation.
Mg-rich olivine has also been discovered in meteorites, on the Moon and Mars, falling into infant stars, as well as on asteroid [url=https://en.wikipedia.org/wiki/25143_Itokawa]25143 Itokawa[/url]. Such meteorites include chondrites, collections of debris from the early Solar System; and pallasites, mixes of iron-nickel and olivine. The rare A-type asteroids are suspected to have a surface dominated by olivine. The spectral signature of olivine has been seen in the dust disks around young stars. The tails of comets (which formed from the dust disk around the young Sun) often have the spectral signature of olivine, and the presence of olivine was verified in samples of a comet from the Stardust spacecraft in 2006. Comet-like (magnesium-rich) olivine has also been detected in the planetesimal belt around the star Beta Pictoris.>>[/quote]