NGC 891. The Silver Sliver Galaxy
NGC 891, also known as the Silver Sliver Galaxy or the Outer Limits Galaxy, is an edge-on unbarred spiral galaxy about 30 million light-years away in the constellation Andromeda. It was discovered by William Herschel on October 6, 1784, and is a member of the group of galaxies of NGC 1023 in the Local Supercluster (LC).
NGC 891 is a SA(s)b? type galaxy with an apparent size of 12' x 1' and an estimated true diameter of 100.000 light years. Some wide angle pictures of our own galaxy, the Milky Way, present a clear resemble with NGC 891.
The shown image of NGC 891 is a color composite made with raw data acquired by NOAO's 4 m KPNO mosaic imager at Kitt Peak National Observatory under program ID 2011B-0355.
The color of the potraited image is fake since I perfomed color mapping by arbitrarily assigning the data taken by NOAO with 3 different filters to the RGB chanels and also because during non linear processing I freely modified the chroma of the galaxy to my own taste.
Data collected by NOAO with H-alpha k1009 filter, with central wavelength 6575 Å and FWHM 80.62 Å, was assigned to the Red channel. Data obtained with R Harris k1004 filter, at 6514 Å and FWHM 1511 Å, was assigned to the Green channel. And data obtained with B Harris k1002 filter, at 4381 Å and FWHM 994 Å, was assigned to the Blue channel.
The NOAO ID 2011B-0355 program was led by New Mexico State University to study stellar streams and star formation in the outskirts of certiain spiral galaxies. The study planed to obtain deep, wide-field observations of ten nearby spiral galaxies. The research needed color information to characterize stellar populations in these galaxies and also deep, high-resolution data in a blue band to determine ages, luminosities, and masses of star formation in the outer disks and halos. The 4 m KPNO's mosaic imager was the instrument selected for the observations.
Image Source:
NOIRLab Astro Data Archive
Text sources:
- NOAO / Observation Information / Approved Programs / 2011B-0355
- Wikipedia.org
NGC 891. The Silver Sliver Galaxy
NGC 891, also known as the Silver Sliver Galaxy or the Outer Limits Galaxy, is an edge-on unbarred spiral galaxy about 30 million light-years away in the constellation Andromeda. It was discovered by William Herschel on October 6, 1784, and is a member of the group of galaxies of NGC 1023 in the Local Supercluster (LC).
NGC 891 is a SA(s)b? type galaxy with an apparent size of 12' x 1' and an estimated true diameter of 100.000 light years. Some wide angle pictures of our own galaxy, the Milky Way, present a clear resemble with NGC 891.
The shown image of NGC 891 is a color composite made with raw data acquired by NOAO's 4 m KPNO mosaic imager at Kitt Peak National Observatory under program ID 2011B-0355.
The color of the potraited image is fake since I perfomed color mapping by arbitrarily assigning the data taken by NOAO with 3 different filters to the RGB chanels and also because during non linear processing I freely modified the chroma of the galaxy to my own taste.
Data collected by NOAO with H-alpha k1009 filter, with central wavelength 6575 Å and FWHM 80.62 Å, was assigned to the Red channel. Data obtained with R Harris k1004 filter, at 6514 Å and FWHM 1511 Å, was assigned to the Green channel. And data obtained with B Harris k1002 filter, at 4381 Å and FWHM 994 Å, was assigned to the Blue channel.
The NOAO ID 2011B-0355 program was led by New Mexico State University to study stellar streams and star formation in the outskirts of certiain spiral galaxies. The study planed to obtain deep, wide-field observations of ten nearby spiral galaxies. The research needed color information to characterize stellar populations in these galaxies and also deep, high-resolution data in a blue band to determine ages, luminosities, and masses of star formation in the outer disks and halos. The 4 m KPNO's mosaic imager was the instrument selected for the observations.
Image Source:
NOIRLab Astro Data Archive
Text sources:
- NOAO / Observation Information / Approved Programs / 2011B-0355
- Wikipedia.org