Em nossa Postagem de hoje,
Mario Jaci Monteiro - As Constelações, Cartas Celestes
- excerto apresentando ALFABETO GREGO, CONVENÇÕES E USO DA CARTA CELESTE
E A CABEÇA DO LEÃO:
Mario Jaci Monteiro - Cartas Celestes, As Constelações - CARJ
|Adhafera, 36 Leonis, HR 4031, BD +24°2209,HD 89025, FK5 384, HIP 50335, SAO 81265,GC 14107, NSV 4804, WDS 10167+2325A.1|
|Algeiba, 41 Leo, BD +20°2467, HIP 50583,LTT 12764/12765, WDS 10200+1950.1|
γ Leo A: HD 89484, HR 4057, SAO 81298.
γ Leo B: HD 89485, HR 4058, SAO 81299.
AO ASTERISMO DA FOICE:
"NGC3041-hst-R814G606B450" por Fabian RRRR - Obra do próprio. Licenciado sob CC BY-SA 3.0, via Wikimedia Commons - https://commons.wikimedia.org/wiki/File:NGC3041-hst-R814G606B450.jpg#/media/File:NGC3041-hst-R814G606B450.jpg
"Phot-17-06-w1" by ESO, Henri Boffin - OLD: http://www.eso.org/gallery/v/ESOPIA/Galaxies/phot-17-06-w1.jpg.htmlhttp://www.eso.org/public/news/eso0617/http://www.eso.org/public/images/eso0617a/Page about Supernova SN 2002bo in NGC 3190. Licensed under CC BY 4.0 via Wikimedia Commons - https://commons.wikimedia.org/wiki/File:Phot-17-06-w1.jpg#/media/File:Phot-17-06-w1.jpg
Image Credit & Copyright: Ken Crawford (Rancho Del Sol Obs.)
Collaboration: David Martinez-Delgado (MPIA, IAC), et al.
"NGC 3227 NGC 3226 Hubble WikiSky" por en:NASA, en:STScI, en:WikiSky - en:WikiSky's snapshot tool - . Licenciado sob Domínio público, via Wikimedia Commons - https://commons.wikimedia.org/wiki/File:NGC_3227_NGC_3226_Hubble_WikiSky.jpg#/media/File:NGC_3227_NGC_3226_Hubble_WikiSky.jpg
NucleusNGC 3226 contains a low-ionization nuclear emission-line region (LINER), a type of region that is characterized by spectral line emission from weakly ionized atoms. In general, the energy source for LINER emission has been a subject of debate among astronomers. Some astronomers have asserted that LINERs are powered by star formation regions, while other have asserted that LINERs are powered by active galactic nuclei (AGN) which contain supermassive black holes.
AGNThe nucleus of NGC 3226 appears to contain an AGN. The nucleus is a strong source of both radio and X-ray emission that appears to be synchrotron emission, which is generated when electrons moving at high speeds oscillate within magnetic fields. Such synchrotron emission is expected from the environment around a supermassive black hole. The X-ray emission may also be variable, which is also expected in the environment of a supermassive black hole.
Interstellar mediumIt is possible that NGC 3226 may be acquiring gas from NGC 3227 during the interaction process, which would enhance star formation within NGC 3226. However, millimeter observations of NGC 3226 failed to detect any molecular gas within the galaxy. These results not only demonstrate that NGC 3226 contains little molecular gas but also demonstrate that the galaxy has acquired no gas from NGC 3227.
Sir William Herschel already recognised them as a 'double nebula' and they were jointly listed as Holm 187 in the Catalogue of Double and Multiple Galaxies and as Arp 94 in the Atlas of Peculiar Galaxies. Amateur telescopes can discern them but require magnification of about 100 times. They are situated 50′ east of the well-known double star system Gamma Leonis (i.e. Algieba).
NucleusNGC 3227 contains a Seyfert nucleus, a type of active galactic nucleus (AGN). Such Seyfert nuclei typically contain supermassive black holes.
As is typical of many AGN, the nucleus of NGC 3227 has been identified as a source of variable X-ray emission. This variability occurs on time scales ranging from a few hours to a few months. The variability may be caused by variations in the density or ionization of gas and dust near the AGN that absorb the X-ray emission. A substantial amount of the X-ray-absorbing gas may lie within 0.4 parsec (1.3 light-years) of the nucleus. An observed change in the shape of the X-ray spectrum in 2000 and 2001 suggests that some of the X-ray absorbing gas is located within 10–100 light-days of the nucleus.
The luminosity of the nucleus reached a maximum in 1977 when evidence suggesting long-lived one-sided or two-sided gas streams was obtained. X-ray radiation of the central accretion disc is reprocessed in one to two days to be re-emitted in the optical spectrum. Infra-red light emission from the hot dust torus lags optical light emission from the nucleus by about 20 days in NGC 3227. The temperature of the dust torus is estimated at 1500 K to 1800 K in NGC 3227 and similar galaxies.
This galaxy was studied by the Multicolor Active Galactic Nuclei Monitoring 2m telescope.
"NGC 3227 NGC 3226 Hubble WikiSky" by en:NASA, en:STScI, en:WikiSky - en:WikiSky's snapshot tool - . Licensed under Public Domain via Wikimedia Commons - https://commons.wikimedia.org/wiki/File:NGC_3227_NGC_3226_Hubble_WikiSky.jpg#/media/File:NGC_3227_NGC_3226_Hubble_WikiSky.jpg