Spiral galaxy NGC 1097

c4ab3333271e1c29779cebb6d8be6161.1824x0_q100_watermark_watermark_opacity-10_watermark_position-4_watermark_text-Copyright Rick Stevenson, 2013

NGC 1097 is a barred spiral galaxy about 45 million light-years away in the constellation Fornax. It was discovered by William Herschel on 9 October 1790. Three supernovae (SN 1992bd, SN 1999eu, and SN 2003B) have been observed in NGC 1097.

NGC 1097 is also a Seyfert galaxy. Deep photographs revealed four narrow optical jets that appear to emanate from the nucleus. These have been interpreted as manifestations of the (currently weak) active nucleus. Subsequent analysis of the brightest jet’s radio-to-X-ray spectral energy distribution were able to rule out synchrotron and thermal free-free emission. The optical jets are in fact composed of stars. The failure to detect atomic hydrogen gas in the jets (under the assumption that they were an example of tidal tails) using deep 21 cm HI imaging with the Very Large Array radio telescope and numerical simulations led to the current interpretation that the jets are actually the shattered remains of a cannibalized dwarf galaxy.

Like most massive galaxies, NGC 1097 has a supermassive black hole at its center. Around the central black hole is a ring ofstar-forming regions with a network of gas and dust that spirals from the ring to the black hole.

NGC 1097 has two satellite galaxies. Dwarf elliptical galaxy NGC 1097A is the larger of the two. It is a peculiar elliptical galaxy that orbits 42,000 light-years from the center of NGC 1097. Dwarf galaxy NGC 1097B (5 x 106 solar masses), the outermost one, was discovered by its HI emission, and appears to be a typical dwarf irregular. Little else is known about it.

Imaging telescopes or lenses: Ceravolo 300 Astrograph (f/9)
Imaging cameras: Apogee Alta U16M
Mounts: Astro-Physics AP900
Guiding telescopes or lenses: Ceravolo 300 Astrograph (f/9)
Guiding cameras: Starlight Xpress Lodestar
Software: DC-3 Dreams ACP, Pleaides Astrophoto PixInsight 1.8, Maxim DL
Filters: Astrodon E-series 2 LRGB
Accessories: FLI Atlas focuser
Dates: Nov. 4, 2013
Frames: 88×900″
Integration: 22.0 hours

Author: Rick Stevenson
AstroPhotography of the day by SPONLI 28 May 2014