Daily Archives: July 23, 2014

IC 4603: Reflection Nebula in Ophiuchius 

Image Credit & Copyright: Rolf Olsen

 Why does this starfield photograph resemble an impressionistic painting? The effect is created not by digital trickery but by large amounts of interstellar dust. Dust, minute globs rich in carbon and similar in size to cigarette smoke, frequently starts in the outer atmospheres of large, cool, young stars. The dust is dispersed as the star dies and grows as things stick to it in the interstellar medium. Dense dust clouds are opaque to visible light and can completely hide background stars. For less dense clouds, the capacity of dust to preferentially reflect blue starlight becomes important, effectively blooming the stars blue light out and marking the surrounding dust. Nebular gas emissions, typically brightest in red light, can combine to form areas seemingly created on an artist’s canvas. Photographed above is the central part of the nebula IC 4603 surrounding the bright star SAO 184376 (actually 8th magnitude) which mostly illuminates the blue reflection nebula. IC 4603 can be seen near the very bright star Antares (1st magnitude) toward the constellation of Ophiuchus.

APOD NASA 23-Jul-2014

M 109 in Ursa Major

4aff0deca4db64dc4f6dd476fc78177c.1824x0_q100_watermark_watermark_opacity-15_watermark_position-1_watermark_text-Copyright Michael Miller
Messier 109 (also known as NGC 3992) is a barred spiral galaxy approximately 83.5 ± 24 million light-years away in the constellation Ursa Major. M109 can be seen southeast of the star Phecda (γ UMa).
In March 1956, supernova 1956A was observed in M109. SN 1956A was a type Ia supernova in the southeast part of the galaxy, glowing at magnitude 12.8 to 12.3 at its maximum. SN 1956A has been the only supernova observed in M109 since its discovery. It is also by far the most distant object in the Messier Catalog, followed by M91. M109 has three satellite galaxies and possibly might have more.

Imaging telescopes or lenses: AG Optical 12.5 IDK
Mounts: Paramount MX
Software: photoshop, DC-3 Dreams ACP, PixInsight PixInsinght 1.8 RC7, Maxim DL
Filters: Astrodon E-series LRGB
Dates: June 1, 2014
Locations: New Mexico Skies
Frames: 75×900″
Integration: 18.8 hours

Author: Mike Miller
AstroPhotography of the day by SPONLI 23 July 2014