Tag: nebula

 

What’s happening in and around the Cave Nebula?

To help find out, NASA’s orbiting Spitzer Space Telescope looked into this optically-dark star-forming region in four colors of infrared light. The Cave Nebula, cataloged as Sh2-155, is quite bright in infrared, revealing details not only of internal pillars of gas and dust, but of the illuminating star cluster too – all near the top of the image.

The red glow around the Cave’s entrance is created by dust heated by bright young stars. To the right is Cepheus B, a star cluster that formed previously from the same cloud of gas and dust.

Other interesting stars of Cepheus come to light in infrared as well, including those illuminating an even younger nebula toward the image bottom, and a runaway star pushing a bow shock, tinged in red near the image center.

This region spans about 50 light years and lies about 2,500 light years toward the constellation of the King of Aethiopia (Cepheus).

Image Credit: NASA, JPL-Caltach, Spitzer Space Telescope

 

Normally faint and elusive, the Jellyfish Nebula is caught in this alluring telescopic field of view. The entire scene is a two panel mosaic constructed using narrowband image data, with emission from sulfur, hydrogen and oxygen atoms shown in red, green and blue hues.

It’s anchored right and left by two bright stars, Mu and Eta Geminorum, at the foot of the celestial twin. The Jellyfish Nebula itself is right of center, the brighter arcing ridge of emission with dangling tentacles.

In fact, the cosmic jellyfish is part of bubble-shaped supernova remnant IC 443, the expanding debris cloud from a massive star that exploded. Light from the explosion first reached planet Earth over 30,000 years ago.

Like its cousin in astrophysical waters the Crab Nebula supernova remnant, the Jellyfish Nebula is known to harbor a neutron star, the remnant of the collapsed stellar core. An emission nebula cataloged as Sharpless 249 fills the field at the upper left. The Jellyfish Nebula is about 5,000 light-years away. At that distance, this image would be about 300 light-years across.

 

 

Interstellar dust clouds and bright nebulae abound in the constellation of Orion. One of the brightest, M78, is near the center in this colorful telescopic view, covering an area north of Orion’s belt.

At a distance of about 1,500 light-years, the nebula is about 5 light-years across. Its blue tint is due to dust preferentially reflecting the blue light of hot stars in the region.

Dark dust lanes and other nebulae can easily be traced through the skyscape that includes many Herbig- Haro objects, energetic jets from stars in the process of formation.

A telescopic view toward the constellation Cassiopeia, the colorful (zoomable) skyscape features the swept-back, comet-shaped clouds IC 59 (left) and IC 63.

 

About 600 light-years distant, the clouds are slowly disappearing under the influence of energetic radiation from hot,luminous star gamma Cas. Gamma Cas is physically located only 3 to 4 light-years from the nebulae, just off the top right edge of the frame.

 

Slightly closer to gamma Cas, IC 63 is dominated by red H-alpha light emitted as hydrogen atoms ionized by the star’s ultraviolet radiation recombine with electrons.

 

Farther from the star, IC 59 shows proportionally less H-alpha emission but more of the characteristic blue tint of dust reflected star light. The field of view spans about 1 degree or 10 light-years at the estimated distance of gamma Cas and friends.

Image Credit & Copyright: Ken Crawford (Rancho Del Sol Obs.)

 

The Cat’s Eye Nebula (NGC 6543) is one of the best known planetary nebulae in the sky. Its haunting symmetries are seen in the very central region of this composited picture, processed to reveal an enormous but extremely faint halo of gaseous material, over three light-years across.

Made with data from ground- and space-based telescopes it shows the extended emission which surrounds the brighter, familiar planetary nebula. Planetary nebulae have long been appreciated as a final phase in the life of a sun-like star.

 

But only more recently have some planetaries been found to have halos like this one, likely formed of material shrugged off during earlier active episodes in the star’s evolution. While the planetary nebula phase is thought to last for around 10,000 years, astronomers estimate the outer filamentary portions of this halo to be 50,000 to 90,000 years old.

Image Credit & Copyright: Data: Michael Joner (West Mountain Observatory, BYU),
Romano Corradi (IAC), Hubble Legacy Archive – Processing: Robert Gendler

 

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).

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

 

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.

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

 

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.

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

 

The striking blue color of the Iris Nebula is created by light from the bright star SAO 19158 reflecting off of a dense patch of normally dark dust. Not only is the star itself mostly blue, but blue light from the star is preferentially reflected by the dust — the same effect that makes Earth’s sky blue.

The brown tint of the pervasive dust comes partly from photoluminescence — dust converting ultraviolet radiation to red light. Cataloged as NGC 7023, the Iris Nebula is studied frequently because of the unusual prevalence there of Polycyclic Aromatic Hydrocarbons (PAHs), complex molecules that are also released on Earth during the incomplete combustion of wood fires.

The bright blue portion of the Iris Nebula spans about six light years. The Iris Nebula, pictured here, lies about 1300 light years distant and can be found with a small telescope toward the constellation of Cepheus.

Image Credit & Copyright: Franco Sgueglia & Francesco Sferlazza

 

There is much more to the familiar Ring Nebula (M57), however, than can be seen through a small telescope. The easily visible central ring is about one light-year across, but this remarkably deep exposure – a collaborative effort combining data from three different large telescopes – explores the looping filaments of glowing gas extending much farther from the nebula’s central star.

This remarkable composite image includes narrowband hydrogen image, visible light emission, and infrared light emission. Of course, in this well-studied example of a planetary nebula, the glowing material does not come from planets. Instead, the gaseous shroud represents outer layers expelled from a dying, sun-like star.

The Ring Nebula is about 2,000 light-years away toward the musical constellation Lyra.

Image Credit: Hubble, Large Binocular Telescope, Subaru Telescope; Composition & Copyright: Robert Gendler