Orion in Red and Blue

 

This colorful rendition of part of the constellation of Orion comes from red light emitted by hydrogen and sulfur (SII), and blue-green light emitted by oxygen (OIII).

Orion in Red and Blue

Hues on the featured image were then digitally reassigned to be indicative of their elemental origins but also striking to the human eye. The breathtaking composite was painstakingly composed from hundreds of images which took nearly 200 hours to collect.

Pictured, Barnard’s Loop, across the image bottom, appears to cradle interstellar constructs including the intricate Orion Nebula seen just right of center. The Flame Nebula can also be quickly located, but it takes a careful eye to identify the slight indentation of the dark Horsehead Nebula. As to Orion’s flashiness  a leading explanation for the origin of Barnard’s Loop is a supernova blast that occurred about two million years ago.

Image Credit & Copyright: David Lindemann

Stars and Dust in Corona Australis

 

Cosmic dust clouds and energetic stars inhabit this telescopic vista, less than 500 light-years away toward the northern boundary of Corona Australis, the Southern Crown.

The dust clouds effectively block light from more distant background stars in the Milky Way. But the striking complex of reflection nebulae cataloged as NGC 6726, 6727, and IC 4812 produce a characteristic color as blue light from the region’s hot stars is reflected by the cosmic dust.

Stars and Dust in Corona Australis

The dust also obscures from view stars still in the process of formation. At top right, smaller yellowish nebula NGC 6729 bends around variable star R Coronae Australis.

Near it, glowing arcs and loops shocked by outflows from embedded newborn stars are identified as Herbig-Haro objects. On the sky this field of view spans about 1 degree. That corresponds to almost 9 light-years at the estimated distance of the nearby star forming region.

Image Credit & Copyright: Josep Drudis

Comet, Clusters and Nebulae

 

Bright enough for binocular viewing Comet 21P / Giacobini-Zinner stands out, even in this deep telephoto mosaic of the star cluster and nebula rich constellation Auriga the Charioteer.

On the night of September 9 its greenish coma and diffuse tail contrast with the colorful stars and reddish emission nebulae in the almost 10 degree field of view along the Milky Way. The comet was near its perihelion and closest approach to Earth, about 200 light-seconds away.

Comet, Clusters and Nebulae

Riding across the distant background just above the comet’s tail are well-known Auriga star clusters M38 (left of center) and M36 (toward the right) about 4,000 light-years away. At the top left, emission region IC 405 is only 1,500 light-years distant, more dramatically known as the Flaming Star Nebula.

To its right lies IC 410, 12,000 light-years away and famous for its star-forming cosmic tadpoles. A child of our Solar System Giacobini-Zinner is a periodic comet orbiting the Sun once every 6.5 years.

Image Credit & Copyright: Mohammad Nouroozi