NGC 3507 is abarred spiral galaxy in the constellationLeo. The galaxy lies about 50 millionlight years away from Earth, which means, given its apparent dimensions, that NGC 3507 is approximately 45,000 light years across.[1] It was discovered byWilliam Herschel on March 14, 1784.[3]
The galaxy features a prominent bar and twospiral arms emerge from the end of the bar at a right angle. It is considered to be agrand design galaxy, as the two arms are well defined. The arms are bright for about half a revolution and can be traced for nearly a full revolution before fading. The Southeast arm wraps more tightly than the northwest one.[4] The inner regions feature knots, which have been identified as young star groupings. About 90 have been detected, with a mean diameter of 121 pc. The galaxy lackshigh-velocity clouds, indicating lowstar formation rate.[5] The star formation rate is estimated to be2.0±0.4 M☉. The hydrogen distribution is clumpy and there is a lowHI signal from the central region of the galaxy.[6]
The nucleus of the galaxy has been found to beactive and has been categorised as aLINER. However its active nucleus status has been questioned, as the ultraviolet radiation and optical spectrum are consistent with the presence of a compact youngstar cluster in the nucleus[7] and the X-ray emission doesn't follow thepower law indicating it could be the result of manysupernova remnants creating asuperbubble.[8][9] On the other hand, OIII/ Hα and NII/ Hα ratios are in line with other active galaxies.[8] A radio counterpart of the core which extends slightly to the south has been observed, indicating the galaxy may have ajet.[8]
The galaxy is seen nearly face-on, at an inclination of 17°.[6]
^Eskridge, Paul B.; Frogel, Jay A.; Pogge, Richard W.; Quillen, Alice C.; Berlind, Andreas A.; Davies, Roger L.; DePoy, D. L.; Gilbert, Karoline M.; Houdashelt, Mark L.; Kuchinski, Leslie E.; Ramirez, Solange V.; Sellgren, K.; Stutz, Amelia; Terndrup, Donald M.; Tiede, Glenn P. (November 2002). "Near-Infrared and Optical Morphology of Spiral Galaxies".The Astrophysical Journal Supplement Series.143 (1):73–111.arXiv:astro-ph/0206320.Bibcode:2002ApJS..143...73E.doi:10.1086/342340.
^Delgado, Rosa M. Gonzalez; Fernandes, Roberto Cid; Perez, Enrique; Martins, Lucimara P.; Storchi-Bergmann, Thaisa; Schmitt, Henrique; Heckman, Timothy; Leitherer, Claus (10 April 2004). "The Stellar Populations of Low-Luminosity Active Galactic Nuclei. II. Space Telescope Imaging Spectrograph Observations".The Astrophysical Journal.605 (1):127–143.arXiv:astro-ph/0401414.Bibcode:2004ApJ...605..127G.doi:10.1086/382216.
^abcKoliopanos, Filippos; Ciambur, Bogdan C.; Graham, Alister W.; Webb, Natalie A.; Coriat, Mickael; Mutlu-Pakdil, Burçin; Davis, Benjamin L.; Godet, Olivier; Barret, Didier; Seigar, Marc S. (May 2017). "Searching for intermediate-mass black holes in galaxies with low-luminosity AGN: a multiple-method approach".Astronomy & Astrophysics.601: A20.arXiv:1612.06794.Bibcode:2017A&A...601A..20K.doi:10.1051/0004-6361/201630061.
^Flohic, Helene M. L. G.; Eracleous, Michael; Chartas, George; Shields, Joseph C.; Moran, Edward C. (10 August 2006). "The Central Engines of 19 LINERs as Viewed by Chandra".The Astrophysical Journal.647 (1):140–160.arXiv:astro-ph/0604487.Bibcode:2006ApJ...647..140F.doi:10.1086/505296.
^Nilson, P. (1973) Uppsala General Catalogue of Galaxies, Acta Universitatis Upsalienis, Nova Regiae Societatis Upsaliensis, Series V: A Vol. 1
