Daily Archives: March 23, 2014

The View Near a Black Hole

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Illustration Credit: April Hobart, CXC

In the center of a swirling whirlpool of hot gas is likely a beast that has never been seen directly: a black hole. Studies of the bright light emitted by the swirling gas frequently indicate not only that a black hole is present, but also likely attributes. The gas surrounding GRO J1655-40, for example, has been found to display an unusual flickering at a rate of 450 times a second. Given a previous mass estimate for the central object of seven times the mass of our Sun, the rate of the fast flickering can be explained by a black hole that is rotating very rapidly. What physical mechanisms actually cause the flickering — and a slower quasi-periodic oscillation(QPO) – in accretion disks surrounding black holes and neutron stars remains a topic of much research.

NASA APOD 23-Mar-2014

Related posts:

  1. The Cloudy Cores of Active Galaxies
  2. A Hole in Mars
  3. The Quiet Sagittarius A*
  4. NGC 4395 in Canes Venatici

Omega nebula in Sagittarius

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The Omega Nebula, also known as the Swan Nebula, Checkmark Nebula, Lobster Nebula, and the Horseshoe Nebula (catalogued asMessier 17 or M17 and as NGC 6618) is an H II region in the constellation Sagittarius. It was discovered by Philippe Loys de Chéseaux in 1745.Charles Messier catalogued it in 1764. It is located in the rich starfields of the Sagittarius area of the Milky Way.

Imaging telescopes or lenses: Astro-Physics AP155 155TCC F5.3
Imaging cameras: FLI ProLine Proline 16803
Mounts: Software Bisque Paramount MX
Guiding telescopes or lenses: Takahashi FS-60C
Guiding cameras: Starlight Xpress Superstar
Focal reducers: Astro-Physics 155TCC
Software: PixInsight 1.8, Software Bisque TheSky6 Professional, FocusMax, Cyanogen Maxim DL Pro 5, Photoshop CS Photo Shop CS5, CCD Autopilot 5
Filters: Astrodon E-series LRGB Ha 5nm
Dates: Aug. 11, 2013
Frames: 50×1200″
Integration: 16.7 hours

Author: David Nguyen

AstroPhotography of the day by SPONLI

23 March 2014

Related posts:

  1. The Cat’s Paw Nebula in Scorpius
  2. Seagull Nebula
  3. Fox Fur Nebula in Monoceros
  4. NGC 6231: Northern Jewel Box