NGC 1275

NGC 1275 (also known as Perseus A or Caldwell 24) is a type 1.5 Seyfert galaxy<ref name="hoetal1997" /> located around 225 million light-years away from Earth<ref name="ned-dist" /> in the direction of the constellation of Perseus. NGC 1275 is a member of the large Perseus Cluster of galaxies. It was discovered by German-British astronomer William Herschel on 17 October 1786.<ref name="selig" />

Properties

{{safesubst:#invoke:Unsubst||date=__DATE__|$B= Template:Ambox }} NGC 1275 consists of two galaxies, a central type-cD galaxy in the Perseus Cluster, and a so-called high velocity system (HVS) which lies in front of it. The HVS is moving at 3000 km/s<ref name="mink" /> towards the dominant system, and is believed to be merging with the Perseus Cluster. The HVS is not affecting the cD galaxy as it lies at least 200 thousand light years from it.<ref name="gill" /> However tidal interactions are disrupting it and the ram pressure produced by its interaction with the intracluster medium of Perseus is stripping its gas as well as producing large amounts of star formation within it.<ref name=Gallagher2010/>

File:Dazzling Galaxy.jpg

Wide multi-wavelength composite view of NGC 1275. An active supermassive black hole in the galaxy powers strong jets of particles into the Perseus Cluster, causing the gas present to reach 60 million degrees Celsius and emit X-ray light (in blue).

The central cluster galaxy contains a massive network of spectral line emitting filaments,<ref>Template:Cite journal</ref> which apparently are being dragged out by rising bubbles of relativistic plasma generated by the central active galactic nucleus.<ref name="hatch" /> Long gaseous filaments made up of threads of gas stretch out beyond the galaxy, into the multimillion-degree, X-ray–emitting gas that fills the cluster. The amount of gas contained in a typical thread is approximately one million times the mass of the Sun. They are only 200 light-years wide, are often very straight, and extend for up to 20,000 light-years.<ref name="newswise" />

The existence of the filaments poses a problem. As they are much cooler than the surrounding intergalactic cloud, it is unclear how they have existed for such a long time, or why they have not warmed, dissipated or collapsed to form stars.<ref name="nature20080821" /><ref name="nytimes20080821">Template:Cite news</ref> One possibility is that weak magnetic fields (about one-ten-thousandth the strength of Earth's field) exert enough force on the ions within the threads to keep them together.<ref name="nature20080821" /><ref name="nytimes20080821" />

NGC 1275 contains 13 billion solar masses of molecular hydrogen that seems to be infalling from Perseus' intracluster medium in a cooling flow, both feeding its active nucleus<ref name=Lim2008/> and fueling significant amounts of star formation<ref name="O'Connell2008" />

The presence of an active nucleus demonstrates that a supermassive black hole is present in NGC 1275's center. The black hole is surrounded by a rotating disk of molecular gas.<ref name=Wilman2005/> High-resolution observations of the rotation of this disk obtained using adaptive optics at the Gemini North telescope indicate a central mass of approximately 800 million solar masses, including both the mass of the black hole and of the inner core of the gas disk.<ref name="Scharwachter2013" />

Supernovae

Three supernovae have so far been observed in NGC 1275:

• SN 1968A (type unknown, mag. 15.5) was discovered by Miklos Lovas on 25 January 1968.<ref>{{#invoke:citation/CS1|citation

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• SN 2005mz (Type Ia, mag. 18.2) was discovered by Jack Newton, M. Peoples, and Tim Puckett on 31 December 2005.<ref>Template:Cite journal</ref><ref>{{#invoke:citation/CS1|citation

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• SN 2024xav ([[Type_II_supernova|TypeTemplate:NbspII-P]], mag. 18.63) was discovered by GOTO on 2 October 2024.<ref>{{#invoke:citation/CS1|citation

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See also

• List of NGC objects (1001–2000)

References

File:NGC1275Location.png

The location of NGC 1275 (circled in red)

External links

• Template:WikiSky
• APOD (2003-05-05) – NASA image & description
• APOD (2005-07-25) – NASA image showing unusual gas filaments
• Fabian, A.C., et al. "A deep Chandra observation of the Perseus cluster: shocks and ripples". Monthly Notices of the Royal Astronomical Society. Vol. 344 (2003): L43 (arXiv:astro-ph/0306036v2).
• Fabian, A.C. Nature 454, 968–970.
• Gabany, R. Jay. cosmotography.com – An image made with a 20" telescope, which displays the unusual gas filaments