A new view of the Tarantula Nebula
To celebrate its 22nd anniversary in orbit, the Hubble Space Telescope released a dramatic new image of the star-forming region 30 Doradus, also known as the Tarantula Nebula because its glowing filaments resemble spider legs.
The nebula is located in the neighboring galaxy called the Large Magellanic Cloud, and is one of the largest star-forming regions located close to the Milky Way. At the center of 30 Doradus, thousands of massive stars are blowing off material and producing intense radiation along with powerful winds.
The Chandra X-ray Observatory detects gas that has been heated to millions of degrees by these stellar winds and also by supernova explosions. These X-rays, colored blue in this composite image, come from shock fronts—similar to sonic booms—formed by this high-energy stellar activity.
The Hubble data, colored green, reveals the light from these massive stars along with different stages of star birth, including embryonic stars a few thousand years old still wrapped in cocoons of dark gas. Infrared emission data from Spitzer, seen in red, shows cooler gas and dust that have giant bubbles carved into them. These bubbles are sculpted by the same searing radiation and strong winds that comes from the massive stars at the center of 30 Doradus.
Evaporating Blobs of the Carina Nebula
The unusual blobs found in the Carina nebula, some of which are seen floating on the upper right, might best be described as evaporating. Energetic light and winds from nearby stars are breaking apart the dark dust grains that make the iconic forms opaque.
Ironically the blobs, otherwise known as dark molecular clouds, frequently create in their midst the very stars that later destroy them. The floating space mountains pictured above by the orbiting Hubble Space Telescope span a few light months.
The Great Nebula in Carina itself spans about 30 light years, lies about 7,500 light years away, and can be seen with a small telescope toward the constellation of Carina.
M57: The Ring Nebula
Except for the rings of Saturn, the Ring Nebula (M57) is probably the most famous celestial band. Its classic appearance is understood to be due to perspective - our view from planet Earth looks down the center of a roughly barrel-shaped cloud of glowing gas.
But expansive looping structures are seen to extend far beyond the Ring Nebula’s familiar central regions in this intriguing composite of ground based and Hubble Space Telescope images with narrowband image data from Subaru.
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 the dying, once sun-like star at the nebula’s center. Intense ultraviolet light from the hot central star ionizes atoms in the gas.
Ionized oxygen atoms produce the characteristic greenish glow and ionized hydrogen the prominent red emission. The central ring of the Ring Nebula is about one light-year across and 2,000 light-years away. To accompany tonight’s shooting stars it shines in the northen constellation Lyra.
Hubble’s Panoramic View of 30 Doradus
Several million stars are vying for attention in this Hubble Space Telescope image of a raucous stellar breeding ground in 30 Doradus, located in the heart of the Tarantula nebula. The image is being released to celebrate Hubble’s 22nd anniversary.
30 Doradus is the brightest star-forming region in our galactic neighbourhood and home to the most massive stars ever seen. The nebula resides 170,000 light-years away in the Large Magellanic Cloud, a small, satellite galaxy of our Milky Way. No known star-forming region in our galaxy is as large or as prolific as 30 Doradus.
The image is roughly 650 light-years across and comprises one of the largest mosaics ever assembled from Hubble photos and consists of observations taken by Hubble’s Wide Field Camera 3 and Advanced Camera for Surveys, combined with observations from ESO’s MPG/ESO 2.2-metre telescope that trace the location of glowing hydrogen and oxygen.
The region’s sparkling centerpiece is a giant, young star cluster named NGC 2070, only 2-3 million years old. Its stellar inhabitants number roughly 500,000. The cluster is a hotbed for young, massive stars. Its dense core, known as RMC 136, is packed with some of the heftiest stars found in the nearby Universe, weighing more than 100 times the mass of our Sun.
The image reveals a fantasy landscape of pillars, ridges, and valleys. The massive stars are carving deep cavities in the surrounding material by unleashing a torrent of ultraviolet light, which is etching away the enveloping hydrogen gas cloud in which they were born. When this radiation hits dense walls of gas, it creates shocks, which may be generating a new wave of star birth.
Images: 1. Hubble’s panoramic view of the 30 Doradus (also known as the Tarantula Nebula) star-forming region. 2. Labelled view of the Tarantula Nebula identifying several prominent features.
The Eagle Nebula from Kitt Peak
From afar, the whole thing looks like an Eagle. A closer look at the Eagle Nebula, however, shows the bright region is actually a window into the center of a larger dark shell of dust. Through this window, a brightly-lit workshop appears where a whole open cluster of stars is being formed.
In this cavity tall pillars and round globules of dark dust and cold molecular gas remain where stars are still forming. Already visible are several young bright blue stars whose light and winds are burning away and pushing back the remaining filaments and walls of gas and dust.
The Eagle emission nebula, tagged M16, lies about 6500 light years away, spans about 20 light-years, and is visible with binoculars toward the constellation of Serpens. This picture combines three specific emitted colors and was taken with the 0.9-meter telescope on Kitt Peak, Arizona, USA.
Hubble Peeks inside a Stellar Cloud
These bright stars shining through what looks like a haze in the night sky are part of a young stellar grouping in one of the largest known star formation regions of the Large Magellanic Cloud (LMC), a dwarf satellite galaxy of the Milky Way. The image was captured by the Hubble Space Telescope’s Wide Field Planetary Camera 2.
The stellar grouping is known as NGC 2040 or LH 88. It is essentially a very loose star cluster whose stars have a common origin and are drifting together through space. NGC 2040 is an OB association, a grouping that usually contains 10–100 stars of type O and B. It is thought that most of the stars in the Milky Way were born in OB associations.
NGC 2040 consists of several high-mass young stars in a large nebula of partially ionised hydrogen gas, and lies in what is known to be a supergiant shell of gas called LMC 4. Over a period of several million years, thousands of stars may form in these supergiant shells, which are the largest interstellar structures in galaxies.
The shells themselves are believed to have been created by strong stellar winds and clustered supernova explosions of massive stars that blow away surrounding dust and gas, and in turn trigger further episodes of star formation.
Cosmic Jet Looks Like Giant Tornado in Space
While examining a region where new stars are forming with NASA’s Spitzer Space Telescope, astronomers found a surprise - an object that looks like a giant tornado in space. The apparent tornado is shaped by a cosmic jet packing a powerful punch as it plows through clouds of interstellar gas and dust.
The “tornado” is actually a shock front created by a jet of material flowing downward through the field of view. A still-forming star located off the upper edge of the image, designated Herbig-Haro 49/50, generates this outflow.
The jet slams into neighboring dust clouds at a speed of more than 100 miles per second, heating the dust to incandescence and causing it to glow with infrared light detectable by Spitzer. The triangular shape results from the wake created by the jet’s motion, similar to the wake behind a speeding boat.
Most striking about the color-coded infrared image is the color gradient from one end of the “tornado” to the other. The blue color at the tornado’s tip results from high molecular excitation at the head of the shock. Those high excitation levels generate more short-wavelength emission, shown as blue. Molecular excitation levels decrease away from the head of the bow shock; therefore the emission is at longer wavelengths, colored red here.
This wide-field view of the star-forming region NGC 281 was taken with the WIYN 0.9-meter telescope at Kitt Peak National Observatory near Tucson, AZ. The iamge shows a centralized cluster of hot blue stars, dust and gas, and lanes of obscuring dust. NGC 281 is about 9,500 light years from Earth in the constellation Cassiopeia.
NGC 7635: The Bubble Nebula
NGC 7635, the Bubble Nebula, is being pushed out by the stellar wind of massive central star BD+602522. Next door, though, lives a giant molecular cloud, visible above to the lower right. At this place in space, an irresistible force meets an immovable object in an interesting way.
The cloud is able to contain the expansion of the bubble gas, but gets blasted by the hot radiation from the bubble’s central star. The radiation heats up dense regions of the molecular cloud causing it to glow.
The Bubble Nebula, pictured above in scientifically mapped colors to bring up contrast, is about 10 light-years across and part of a much larger complex of stars and shells. The Bubble Nebula can be seen with a small telescope towards the constellation of Cassiopeia.
IC 410 in Auriga, the scale in a sky
This zoom in series of photographs of the emission nebula IC 410 was taken by Finnish astrophotographer J-P Metsavainio from his observatory at the city center of Oulu. The images show the actual size of IC 410 in the sky. The white circle in the images show the angular size of the full Moon in the sky. The Moon has an apparent diameter of ~30 arc minutes or 0,5 degrees.
A Fox Fur, a Unicorn, and a Christmas Tree
Pictured above is a star forming region cataloged as NGC 2264, located in the constellation of the unicorn (Monoceros).
The complex jumble of cosmic gas and dust is about 2,700 light-years distant and mixes reddish emission nebulae excited by energetic light from newborn stars with dark interstellar dust clouds. Where the otherwise obscuring dust clouds lie close to the hot, young stars they also reflect starlight, forming blue reflection nebulae.
The above image covers 40 light-years at the distance of NGC 2264. Its cast of cosmic characters includes the Fox Fur Nebula, whose convoluted pelt lies at the upper left, bright variable star S Mon immersed in the blue-tinted haze just below the Fox Fur, and the Cone Nebula near the tree’s top.
The stars of NGC 2264 are also known as the Christmas Tree star cluster. The triangular tree shape traced by the stars appears sideways here, with its apex at the Cone Nebula and its broader base centered near S Mon.
Chaos in Orion
Baby stars are creating chaos 1,500 light-years away in the cosmic cloud of the Orion Nebula. Four massive stars make up the bright yellow area in the center of this false-color image for NASA’s Spitzer Space Telescope. Green indicates hydrogen and sulfur gas in the nebula, which is a cocoon of gas and dust. Red and orange indicate carbon-rich molecules. Infant stars appear as yellow dots embedded in the nebula.
GK Persei: Nova of 1901
In 1901, an obscure star in the constellation of Perseus suddenly flared into brightness, becoming briefly one of the brightest stars in the sky. Called GK Persei (or Nova Persei 1901), it’s an odd beast. While some stars like this just fade away after such an event, even now, more than a century later, GK Persei still suffers through periodic explosions, emitting vast pulses of energy.
This type of system is called a cataclysmic variable star. It’s a binary: one of the stars is a white dwarf, an ultra-dense ball of matter that used to be the core of a normal star like the Sun. When that star reached the end of its life, it shed its outer layers, exposing its core to space.
The other star is a swollen red giant, also nearing the end of its life. Material from the red giant falls onto the white dwarf, where it piles up. The surface gravity of the dwarf can be a hundred thousand times that of Earth. This compresses the infalling material so much that when the pile gets big enough it can cause spontaneous nuclear fusion.
The resulting explosion is incredibly violent, and blasts a lot of the material into space. After a while, things settle down, and the matter starts piling up again, repeating the cycle. It’s not the same every time, as the 1901 nova was quite the singular event. So sometimes the star is more violent than others. Recently GK Persei has been acting up again, undergoing brighter flares, though nothing like the 1901 explosion.
You can view an animation showing the nebula expanding over 17 years, from 1994 to 2011 here: http://vimeo.com/31120259
The Tadpoles of IC410
From his home observatory in Connellsville, Pa., avid astrophotographer Bill Snyder took this stunning photo of the so-called “tadpoles” of the emission nebula IC410 on Jan. 15. IC410 is located roughly 12,000 light-years away toward the constellation Auriga.
The tadpoles in this image are actually about 10 light-years long and are potential sites of star formation. The nebula itself surrounds the young cluster of stars called NGC 1893. This cluster energizes the denser, cooler gas making up the tadpoles. Their unique shape is sculpted by wind and radiation from the cluster stars.
Snyder used a TMB130mm telescope equipped with an Apogee U8300 camera, as well as a mount and several filters to create this view of IC410. He had a total exposure time of more than 14 hours to capture this view of the nebula.
NASA’s SOFIA captures image of dying, outflowing star
Researchers using NASA’s Stratospheric Observatory for Infrared Astronomy (SOFIA) have captured an infrared image of the last exhalations of a dying sun-like star. The planetary nebula Minkowski 2-9 (M2-9) is seen in this three-color composite image.
Although the M2-9 nebular material is flowing out from a spherical star, it is extended in one dimension, appearing as a cylinder or hourglass. Planetary nebulae with such shapes are produced by opposing flows of high-speed material caused by a disk of material around the dying star, located at the center of the nebula.
SOFIA’s observations of M2-9 were designed to study the outflow in detail with the goal of better understanding this stellar life cycle stage, which is important in our galaxy’s evolution. The observations were made at the 37-micron wavelength band which detects the strongest emissions from the nebula and is impossible to observe from ground-based telescopes.
The SOFIA observatory combines an extensively modified Boeing 747SP aircraft and a 17-metric-ton reflecting telescope with an effective diameter of 100 inches (2.5 meters) to altitudes as high as 45,000 feet (14 kilometers). This places the telescope above more than 99 percent of the water vapor in Earth’s atmosphere that blocks most infrared radiation from celestial sources.