Hubble and Spitzer Space Telescopes Find "Lego-Block" Galaxies in Early Universe
Spitzer and Hubble Team Up T
Title
Spitzer and Hubble Team Up To Find 'Big Baby' Galaxies in the Newborn Universe
Description
This image demonstrates how data from two of NASA's Great Observatories, the Spitzer and Hubble Space Telescopes, are used to identify one of the most distant galaxies ever seen. This galaxy is unusually massive for its youthful age of 800 million years. (After the Big Bang, the Milky Way by comparison, is approximately 13 billion years old.) [Left] - The galaxy, named HUDF-JD2, was pinpointed among approximately 10,000 others in a small area of sky called the Hubble Ultra Deep Field. This is the deepest images of the universe ever made at optical and near-infrared wavelengths. [Upper Right] - A blow-up of one small area of the Hubble Ultra Deep Field is used to identify where the distant galaxy is located (inside green circle). This indicates that the galaxy's visible light has been absorbed by traveling billions of light-years through intervening hydrogen. [Center Right] - The galaxy was detected using Hubble's near infrared camera and multi-object spectrometer. But at near-infrared wavelengths it is very faint and red. [Bottom Right] - The Spitzer infrared array camera, easily detects the galaxy at longer infrared wavelengths. The instrument is sensitive to the light from older, redder stars which should make up most of the mass in a galaxy. The brightness of the infrared galaxy suggests that it is quite massive.
Mystery Solved: High-Energy
Title
Mystery Solved: High-Energy Fireworks Linked to Massive Star Cluster
General Information
What is an American Astronomical Society Meeting release? A major news announcement issued at an American Astronomical Society meeting, the premier astronomy conference. Call it the Bermuda Triangle of our Milky Way Galaxy: a tiny patch of sky that has been known for years to be the source of the mysterious blasts of X-rays and gamma rays. Now, a team of astronomers, led by Don Figer of the Space Telescope Science Institute in Baltimore, Md., has solved the mystery by identifying one of the most massive star clusters in the galaxy. The little-known cluster, which has not been catalogued, is about 20 times more massive than typical star clusters in our galaxy, and appears to be the source of the powerful outbursts. Supporting evidence for the hefty weight of this cluster is the presence of 14 red supergiants, hefty stars that have reached the end of their lives. They bloat up to about 100 times their normal size before exploding as supernovae. This image shows the star-studded region surrounding the massive star cluster. The bluish cluster is inside the white box. A close-up of the cluster can be seen in the inset photo. Read more: * The Full Story [ http://hubblesite.org/newscenter/archive/releases/2006/03/full/ ]
Hubble Uncovers a Baby Galax
Title
Hubble Uncovers a Baby Galaxy in a Grown-Up Universe
Big Galaxy in Baby Universe
PIA03542
Infrared Array Camera (IRAC)
Title
Big Galaxy in Baby Universe
Original Caption Released with Image
Figure 1 for PIA03542 Big Galaxy in Baby Universe This image demonstrates how data from two of NASA's Great Observatories, the Spitzer and Hubble Space Telescopes, are used to identify one of the most distant galaxies ever seen. This galaxy is unusually massive for its youthful age of 800 million years. (After the Big Bang, the Milky Way by comparison, is approximately 13 billion years old.) The galaxy, named HUDF-JD2, was pinpointed among approximately 10,000 others in a small area of sky called the Hubble Ultra Deep Field This is the deepest images of the universe ever made at optical and near-infrared wavelengths (upper left). A blow-up of one small area of the Hubble Ultra Deep Field is used to identify where the distant galaxy is located (inside green circle). This indicates that the galaxy's visible light has been absorbed by traveling billions of light-years through intervening hydrogen (upper right). The galaxy was detected using Hubble's near infrared camera and multi-object spectrometer. But at near-infrared wavelengths it is very faint and red (bottom left). The Spitzer infrared array camera, easily detects the galaxy at longer infrared wavelengths. The instrument is sensitive to the light from older, redder stars which should make up most of the mass in a galaxy. The brightness of the infrared galaxy suggests that it is quite massive (bottom right).
Hubble Tracks Asteroid's Sky
Title
Hubble Tracks Asteroid's Sky Trek
General Information
What is Hubble Heritage? A monthly showcase of new and archival Hubble images. Go to the Heritage site. Back to top [ #top ]
Spitzer Leads NASA's Great O
Title
Spitzer Leads NASA's Great Observatories to Uncover Black Holes, Other Hidden Objects in the Distant Universe
General Information
What is an American Astronomical Society Meeting release? A major news announcement issued at an American Astronomical Society meeting, the premier astronomy conference. Back to top [ #top ]
Hubble Photographs Grand Des
Title
Hubble Photographs Grand Design Spiral Galaxy M81
General Information
What is Hubble Heritage? A monthly showcase of new and archival Hubble images. Go to the Heritage site. What is an American Astronomical Society Meeting release? A major news announcement issued at an American Astronomical Society meeting, the premier astronomy conference. The sharpest image ever taken of the large "grand design" spiral galaxy M81 is being released today at the American Astronomical Society Meeting in Honolulu, Hawaii. A spiral-shaped system of stars, dust, and gas clouds, the galaxy's arms wind all the way down into the nucleus. Though the galaxy is located 11.6 million light-years away, the Hubble Space Telescope's view is so sharp that it can resolve individual stars, along with open star clusters, globular star clusters, and even glowing regions of fluorescent gas. The Hubble data was taken with the Advanced Camera for Surveys in 2004 through 2006. This color composite was assembled from images taken in blue, visible, and infrared light.
Hubble Celebrates 15th Anniv
Title
Hubble Celebrates 15th Anniversary with Spectacular New Images
General Information
What is Hubble Heritage? A monthly showcase of new and archival Hubble images. Go to the Heritage site. Back to top [ #top ]
Nearby Dust Clouds in the Mi
Title
Nearby Dust Clouds in the Milky Way
General Information
What is Hubble Heritage? A monthly showcase of new and archival Hubble images. Go to the Heritage site. NASA's Hubble Space Telescope has photographed dense knots of dust and gas in our Milky Way Galaxy. This cosmic dust is a concentration of elements that are responsible for the formation of stars in our galaxy and throughout the universe. These dark, opaque knots of gas and dust are called "Bok globules," and they are absorbing light in the center of the nearby emission nebula and star-forming region, NGC 281. These images were taken with Hubble's Advanced Camera for Surveys in October 2005. NGC 281 is located nearly 9,500 light-years away in the direction of the constellation Cassiopeia.
Hubble Finds Mysterious Disk
Title
Hubble Finds Mysterious Disk of Blue Stars Around Black Hole
Hubble Tracks Asteroid's Sky
Title
Hubble Tracks Asteroid's Sky Trek
General Information
What is Hubble Heritage? A monthly showcase of new and archival Hubble images. Go to the Heritage site. Back to top [ #top ]
Hubble Spies a Zoo of Galaxi
Title
Hubble Spies a Zoo of Galaxies
General Information
What is Hubble Heritage? A monthly showcase of new and archival Hubble images. Go to the Heritage site. Gazing deep into the universe, NASA?s Hubble Space Telescope has spied a menagerie of galaxies. Located within the same tiny region of space, these numerous galaxies display an assortment of unique characteristics. Some are big, some are small. A few are relatively nearby, but most are far away. Hundreds of these faint galaxies have never been seen before until their light was captured by Hubble.
Astronomers Track Down Aster
Title
Astronomers Track Down Asteroids in Hubble Archive
Hubble Discovers Black Holes
Title
Hubble Discovers Black Holes in Unexpected Places
General Information
What is a Space Science Update? Major Hubble discoveries on NASA television ... Astronomers explain their Hubble discoveries at a press conference, called a Space Science Update (SSU), broadcast on NASA television. The SSU includes a question and answer session with members of the media. Back to top [ #top ]
Hubble Finds Double Einstein
Title
Hubble Finds Double Einstein Ring
General Information
What is an American Astronomical Society Meeting release? A major news announcement issued at an American Astronomical Society meeting, the premier astronomy conference. The Hubble Space Telescope has revealed a never-before-seen optical alignment in space: a pair of glowing rings, one nestled inside the other like a bull's-eye pattern. The double-ring pattern is caused by the complex bending of light from two distant galaxies strung directly behind a foreground massive galaxy, like three beads on a string. This very rare phenomenon can offer insight into dark matter, dark energy, the nature of distant galaxies, and even the curvature of the universe. The phenomenon, called gravitational lensing, occurs when a massive galaxy in the foreground bends the light rays from a distant galaxy behind it, in much the same way as a magnifying glass would. When both galaxies are exactly lined up, the light forms a circle, called an "Einstein ring," around the foreground galaxy. If another background galaxy lies precisely on the same sightline, a second, larger ring will appear. The massive foreground galaxy is almost perfectly aligned in the sky with two background galaxies at different distances. The foreground galaxy is 3 billion light-years away. The inner ring and outer ring are comprised of multiple images of two galaxies at a distance of 6 billion and approximately 11 billion light-years. The odds of seeing such a special alignment are estimated to be 1 in 10,000. Read more: * The Full Story [ http://hubblesite.org/newscenter/archive/releases/2008/04/full/ ]
Story of Stellar Birth
Title
Story of Stellar Birth
Description
This image from NASA's Spitzer Space Telescope reveals the complex life cycle of young stars, from their dust-shrouded beginnings to their stellar debuts. The stellar nursery was spotted in a cosmic cloud sitting 21,000 light-years away in the Cepheus constellation. A star is born when a dense patch gas and dust collapses inside a cosmic cloud. In the first million years of a star's life, it is hidden from visible-light view by the cloud that created it. Eventually as the star matures, its strong winds and radiation blow away surrounding material and the star fully reveals itself to the universe. The first stages of stellar life are represented by the greenish yellow dot located in the center of the image (just to the right of the blue dot). Astronomers suspect that this source is less than a million years old because spectra of the region (right bottom graph) reveal a deep absorption feature due to silicate dust (crushed crystalline grains that are smaller than sand) indicating that the star is still deeply embedded inside the cosmic cloud that collapsed to form it. Wisps of green surrounding the star and its nearby environment illustrate the presence of hot hydrogen gas. Above and to the left of the central greenish yellow dot, a large, bright pinkish dot reveals a more mature star on the verge of emerging from its natal cocoon. Although this star is still shrouded by its birth material, astronomers use Spitzer, a temperature-sensitive infrared telescope, to see the surrounding gas and dust that is being heated up by the star. The region's oldest and fully exposed stars can be seen as bunches of blue specks located just left of the concave ridge. Energetic particles and ultraviolet photons from nearby star clusters etched this arc into the cloud by blowing away surrounding dust and gas. Spectral observations of the ridge (right top graph) and reddish-white dot, or "mature star" (right middle graph), indicate the presence of carbon rich molecules called polycyclic aromatic hydrocarbons (PAHs), which are found on barbecue grills and in automobile exhaust on Earth. The featured image is a four-channel false-color composite, where blue indicates emission at 3.6 microns, green corresponds to 4.5 microns, and red to 5.8 and 8.0 microns. The image was taken by Spitzer's Infrared Array Camera (IRAC). Spectra of the region were obtained with the telescope's Infrared Spectrometer (IRS) instrument.
Deepest View of Space Yields
Title
Deepest View of Space Yields Young Stars in Andromeda Halo
Very Long Baseline Array Rev
Title
Very Long Baseline Array Reveals Formation Region of Giant Cosmic Jet Near a Black Hole
Hubble Finds that "Blue Blob
Title
Hubble Finds that "Blue Blobs" in Space Are Orphaned Clusters of Stars
General Information
What is Hubble Heritage? A monthly showcase of new and archival Hubble images. Go to the Heritage site. What is an American Astronomical Society Meeting release? A major news announcement issued at an American Astronomical Society meeting, the premier astronomy conference. Hubble Space Telescope's powerful vision has resolved strange objects nicknamed "blue blobs" and found them to be brilliant blue clusters of stars born in the swirls and eddies of a galactic smashup 200 million years ago. Such "blue blobs"—, weighing tens of thousands of solar masses —, have never been seen in detail before in such sparse locations, say researchers. The "blue blobs" are found along a wispy bridge of gas strung among three colliding galaxies, M81, M82, and NGC 3077, residing about 12 million light-years away from Earth. This is not the place astronomers expect to find star clusters, because the gas filaments were considered too thin to accumulate enough material to actually build these many stars. The star clusters in this diffuse structure might have formed from gas collisions and subsequent turbulence, which enhanced locally the density of the gas streams. Galaxy collisions were much more frequent in the early universe, so "blue blobs" should have been common. After the stars burned out or exploded, the heavier elements forged in their nuclear furnaces would have been ejected to enrich intergalactic space. Read more: * The Full Story [ http://hubblesite.org/newscenter/archive/releases/2008/02/full/ ]
Hubble Snaps Picture of Rema
Title
Hubble Snaps Picture of Remarkable Double Cluster
Biggest 'Zoom Lens' in Space
Title
Biggest 'Zoom Lens' in Space Takes Hubble Deeper into the Universe
General Information
What is an American Astronomical Society Meeting release? A major news announcement issued at an American Astronomical Society meeting, the premier astronomy conference. Back to top [ #top ]
A SWIRE Picture is Worth Bil
Title
A SWIRE Picture is Worth Billions of Years
Description
These spectacular images, taken by the Spitzer Wide-area Infrared Extragalactic (SWIRE) Legacy project, encapsulate one of the primary objectives of the Spitzer mission: to connect the evolution of galaxies from the distant, or early, universe to the nearby, or present day, universe. The larger picture (top) depicts one-tenth of the SWIRE survey field called ELAIS-N1. In this image, the bright blue sources are hot stars in our own Milky Way, which range anywhere from 3 to 60 times the mass of our Sun. The fainter green spots are cooler stars and galaxies beyond the Milky Way whose light is dominated by older stellar populations. The red dots are dusty galaxies that are undergoing intense star formation. The faintest specks of red-orange are galaxies billions of light-years away in the distant universe. The three lower panels highlight several regions of interest within the ELAIS-N1 field. The Tadpole galaxy (bottom left) is the result of a recent galactic interaction in the local universe. Although these galactic mergers are rare in the universe's recent history, astronomers believe that they were much more common in the early universe. Thus, SWIRE team members will use this detailed image of the Tadpole galaxy to help understand the nature of the "faint red-orange specks" of the early universe. The middle panel features an unusual ring-like galaxy called CGCG 275-022. The red spiral arms indicate that this galaxy is very dusty and perhaps undergoing intense star formation. The star-forming activity could have been initiated by a near head-on collision with another galaxy. The most distant galaxies that SWIRE is able to detect are revealed in a zoom of deep space (bottom right). The colors in this feature represent the same objects as those in the larger field image of ELAIS-N1. The observed SWIRE fields were chosen on the basis of being "empty" or as free as possible from the obscuring dust, gas, and stars of our own Milky Way. Because Earth is located within the Milky Way galaxy, there is always a screen of Milky Way objects blocking our view of the rest of the universe. In some places, our view of the larger universe is less obscured than others and for the most part is considered "empty." These are prime observing spots for astronomers interested in studying objects beyond the Milky Way. ELAIS-N1 is only one of six SWIRE survey fields. The full survey covers 49 square degrees of the sky, equivalent to the area covered by about 250 full moons. The SWIRE image is a 3-channel false-color composite, where blue represents visible green light (light that would appear to be blue/green to the human eye), green captures 3.6 microns, and red represents emissions at 8 microns. Interesting Note: From the Earth the SWIRE image (top image) can be seen in one square degree of sky, or a patch of sky that is approximately the size of a pea held out at arms length.
10,000 Galaxies
title
10,000 Galaxies
date
01.16.2004
description
Galaxies, galaxies everywhere - as far as NASA's Hubble Space Telescope can see. This view of nearly 10,000 galaxies is the deepest visible-light image of the cosmos. Called the Hubble Ultra Deep Field, this galaxy-studded view represents a "deep" core sample of the universe, cutting across billions of light-years. The snapshot includes galaxies of various ages, sizes, shapes, and colors. The smallest, reddest galaxies, about 100, may be among the most distant known, existing when the universe was just 800 million years old. The nearest galaxies - the larger, brighter, well-defined spirals and ellipticals - thrived about 1 billion years ago, when the cosmos was 13 billion years old. In vibrant contrast to the rich harvest of classic spiral and elliptical galaxies, there is a zoo of oddball galaxies littering the field. Some look like toothpicks, others like links on a bracelet. A few appear to be interacting. These oddball galaxies chronicle a period when the universe was younger and more chaotic. Order and structure were just beginning to emerge. The Ultra Deep Field observations, taken by the Advanced Camera for Surveys, represent a narrow, deep view of the cosmos. Peering into the Ultra Deep Field is like looking through an eight-foot-long soda straw. In ground-based photographs, the patch of sky in which the galaxies reside (just one-tenth the diameter of the full Moon) is largely empty. Located in the constellation Fornax, the region is so empty that only a handful of stars within the Milky Way galaxy can be seen in the image. In this image, blue and green correspond to colors that can be seen by the human eye, such as hot, young, blue stars and the glow of Sun-like stars in the disks of galaxies. Red represents near-infrared light, which is invisible to the human eye, such as the red glow of dust-enshrouded galaxies. The image required 800 exposures taken over the course of 400 Hubble orbits around Earth. The total amount of exposure time was 11.3 days, taken between Sept. 24, 2003 and Jan. 16, 2004. *Image Credit*: NASA, ESA, S. Beckwith (STScI) and the HUDF Team
Black Widow Nebula Hiding in
Title
Black Widow Nebula Hiding in the Dust
Description
In the constellation Circinus, where previous visible-light observations by the Digital Sky Survey (left) saw only a faint hourglass-shaped patch of obscuring dust and gas, NASA's Spitzer Space Telescope's dust-piercing eyes see a big "Black Widow Nebula" teeming with clusters of massive young stars (right). In the Spitzer image, the two opposing bubbles are being formed in opposite directions by the powerful outflows from massive groups of forming stars. The baby stars can be seen as specks of yellow where the two bubbles overlap. When individual stars form from molecular clouds of gas and dust they produce intense radiation and very strong particle winds. Both the radiation and the stellar winds blow the dust outward from the star creating a cavity or, bubble. In the case of the Black Widow Nebula, astronomers suspect that a large cloud of gas and dust condensed to create multiple clusters of massive star formation. The combined winds from these groups of large stars probably blew out bubbles into the direction of least resistance, forming a double bubble. The infrared image was captured by the Galactic Legacy Infrared Mid-Plane Survey Extraordinaire (GLIMPSE) Legacy project. The Spitzer picture is a four-channel false-color composite, showing emission from wavelengths of 3.6 microns (blue), 4.5 microns (green), 5.8 microns (orange) and 8.0 microns (red).
Dwarfs in Coma Cluster
Title
Dwarfs in Coma Cluster
Description
This false-color mosaic of the central region of the Coma cluster combines infrared and visible-light images to reveal thousands of faint objects (green). Follow-up observations showed that many of these objects, which appear here as faint green smudges, are dwarf galaxies belonging to the cluster. Two large elliptical galaxies, NGC 4889 and NGC 4874, dominate the cluster's center. The mosaic combines visible-light data from the Sloan Digital Sky Survey (color coded blue) with long- and short-wavelength infrared views (red and green, respectively) from NASA's Spitzer Space Telescope.
Starry Bulges Yield Secrets
Title
Starry Bulges Yield Secrets to Galaxy Growth
General Information
What is a Space Science Update? Major Hubble discoveries on NASA television ... Astronomers explain their Hubble discoveries at a press conference, called a Space Science Update (SSU), broadcast on NASA television. The SSU includes a question and answer session with members of the media. The Hubble telescope is uncovering important new clues to a galaxy's birth and growth by peering into its heart ? a bulge of millions of stars resembling a bulbous center yolk in the middle of a disk of egg white. Astronomers have combined information from the Hubble telescope's visible- and infrared-light cameras to show the heart of four spiral galaxies peppered with ancient populations of stars. The top row of pictures, taken by a ground-based telescope, represents complete views of each galaxy. The blue boxes outline the regions observed by the Hubble telescope. The bottom row represents composite pictures from Hubble's visible- and infrared-light cameras. Astronomers combined views from both cameras to obtain the true ages of the stars surrounding each galaxy's bulge. The Hubble telescope's sharper resolution allows astronomers to study the intricate structure of a galaxy's central region. Read more: * Release Text [ http://hubblesite.org/newscenter/archive/releases/1999/34/text/ ]
The Carina Nebula: Star Birt
Title
The Carina Nebula: Star Birth in the Extreme
General Information
What is Hubble Heritage? A monthly showcase of new and archival Hubble images. Go to the Heritage site. In celebration of the 17th anniversary of the launch and deployment of NASA's Hubble Space Telescope, a team of astronomers is releasing one of the largest panoramic images ever taken with Hubble's cameras. READ: Junior version of this article Amazing Space Learn about this story in the Star Witness, a science newspaper available on our sister site, Amazing Space. [ http://amazing-space.stsci.edu/news/archive/2007/02/ ] It is a 50-light-year-wide view of the central region of the Carina Nebula where a maelstrom of star birth —, and death —, is taking place. This image is a mosaic of the Carina Nebula assembled from 48 frames taken with Hubble's Advanced Camera for Surveys. The Hubble images were taken in the light of neutral hydrogen during March and July 2005. Color information was added with data taken in December 2001 and March 2003 at the Cerro Tololo Inter-American Observatory in Chile. Red corresponds to sulfur, green to hydrogen, and blue to oxygen emission.
Natural Lenses in Space Stre
Title
Natural Lenses in Space Stretch Hubble's View of the Universe
Hubble Pans Across Heavens t
Title
Hubble Pans Across Heavens to Harvest 50,000 Evolving Galaxies
Io: Cylindrical Projection
PIA00401
Jupiter
Imaging Science Subsystem -
Title
Io: Cylindrical Projection
Original Caption Released with Image
New multispectral image cube of Io from Voyager 2 images, simple cylindrical projection. Top: Natural color, Middle: enhanced color, Bottom: color-ratio composite. Improvements compared to old global mosaics of McEwen (1988) allow us to recognize new spectral units and relations and will facilitate comparisons to HST and Galileo observations.
GALEX Distributes Local Gala
PIA03295
GALEX Telescope
Title
GALEX Distributes Local Galactic Treasures at AAS
Original Caption Released with Image
GALEX Poster From sparkling blue rings to dazzling golden disks, Galaxy Evolution Explorer (Galex) scientists are handing out a collection of their finest galactic treasures at the January 2006 American Astronomical Society meeting in Washington, D.C. Mined from the mission's Survey of Nearby Galaxies data, these cosmic gems were collected with the telescope's sensitive ultraviolet instruments. The gallery of galaxies has been made into a poster for meeting attendees visiting the mission's booth. Organized from far-ultraviolet to near-ultraviolet bright galaxies, this poster encapsulates the heart of the mission to study how galaxies and star formation rates have changed over the past 10 billion years. Events in space take millions or billions of years to unfold, which means that astronomers can't watch individual galaxies and stars age over time. Luckily, because the physics of light travel dictates that the farther away an object is from Earth, the longer it takes for its light to travel to us, the universe can be thought of as a time machine. By building telescopes sensitive enough to capture objects that are 10 billion light-years away, astronomers can essentially see an object the way it looked 10 billion years ago. Galex astronomers are using this phenomenon to their advantage by taking snapshots of different galaxies at various distances in space. By comparing portraits of numerous objects at various times in the universe's history, the team can begin to piece together the life cycle of stars and galaxies. For the poster, Galex scientists organized 196 different nearby galaxies in bins of increasing ultraviolet color. By placing the various snapshots side by side, astronomers can see how galaxies age differently. When viewed in ultraviolet, active star-forming regions in galaxies can be seen as glittering blue structures, while a soft, golden glow indicates the presence of older stars. The 196 galaxies represented in the poster were selected from more than 1,000 galaxies in the "Ultraviolet Atlas of Nearby Galaxies." So far, the Galex mission has surveyed more than 100 million galaxies.
It's Not a Bird or a Plane
PIA07250
GALEX Telescope
Title
It's Not a Bird or a Plane
Original Caption Released with Image
Galaxies aren't the only objects filling up the view of NASA's Galaxy Evolution Explorer. Since its launch in 2003, the space telescope -- originally designed to observe galaxies across the universe in ultraviolet light -- has discovered a festive sky blinking with flaring and erupting stars, as well as streaking asteroids, satellites and space debris. One such streaking object -- possibly an Earth-orbiting satellite -- can be seen here flying across the telescope's sight in this sped-up movie. This probable satellite appears during the last 5 minutes of a 13.5-minute observation. It looks elongated because each picture frame containing the moving object is 19 seconds long. Faint ghost images on either side of the source are detector artifacts caused by the object's extreme brightness. These bonus objects are being collected in to public catalogues for other astronomers to study.
Molecular Cloud Barnard 68
Title
Molecular Cloud Barnard 68
Explanation
Where did all the stars go? What used to be considered a hole in the sky is now known to astronomers as a dark molecular cloud [ http://oposite.stsci.edu/pubinfo/pr/1997/34/af2.html ]. Here, a high concentration of dust [ http://antwrp.gsfc.nasa.gov/apod/ap990509.html ] and molecular gas [ http://antwrp.gsfc.nasa.gov/apod/ap970430.html ] absorb practically all the visible light emitted from background stars. The eerily dark surroundings help make the interiors of molecular clouds [ http://dept.physics.upenn.edu/~myers/ASTR001/L25.html ] some of the coldest and most isolated places in the universe. One of the most notable of these dark absorption nebulae [ http://antwrp.gsfc.nasa.gov/apod/index/DarkNebulae.html ] is a cloud toward the constellation Ophiuchus [ http://www.seds.org/Maps/Stars_en/Fig/ophiuchus.html ] known as Barnard 68, pictured above [ http://www.eso.org/outreach/press-rel/pr-1999/phot-20-99.html ]. That no stars are visible in the center indicates that Barnard [ http://astro.uchicago.edu/yerkes/virtualmuseum/Barnard.html ] 68 is relatively nearby, with measurements placing it about 500 light-years away and half a light-year across. It is not known exactly how molecular clouds [ http://origins.jpl.nasa.gov/poster/bigbang3.html ] like Barnard 68 form, but it is known that these clouds are themselves likely places [ http://antwrp.gsfc.nasa.gov/apod/ap990502.html ] for new stars to form.
Comet NEAT and the Beehive C
Title
Comet NEAT and the Beehive Cluster
Explanation
To the unaided eye, they appeared as similar fuzzy patches. But when a bright comet passed in front of a bright star cluster [ http://antwrp.gsfc.nasa.gov/apod/open_clusters.html ] last month, binoculars and cameras were able to show off their marked differences in dramatic fashion. Pictured above, the bright comet, C/2001 Q4 (NEAT) [ http://www.astronomy.com/Content/Dynamic/Articles/000/000/001/727bsdvn.asp ] shows many details of its coma and tail, while far in the distance the Beehive open cluster, M44 [ http://www.seds.org/messier/m/m044.html ], shows many of its stars. Comet Q4 [ http://skyandtelescope.com/observing/objects/comets/article_1262_1.asp ] has now faded to the edge of unaided visibility and can best be found with a sky map [ http://encke.jpl.nasa.gov/charts.html ] and binoculars from the Northern Hemisphere well into June. Star cluster M44 [ http://antwrp.gsfc.nasa.gov/apod/ap980803.html ] will remain an impressive star cluster toward the constellation [ http://www.astro.wisc.edu/~dolan/constellations/extra/constellations.html ] of Cancer [ http://www.astronomical.org/portal/modules/wfsection/article.php?articleid=12 ] indefinitely.
MyCn18: An Hourglass Nebula
Title
MyCn18: An Hourglass Nebula
Explanation
The sands of time are running out for the central star of this hourglass-shaped planetary nebula [ http://fusedweb.pppl.gov/CPEP/ Chart_Pages/5.Plasmas/Nebula/Planetary.html ]. With its nuclear fuel [ http://fusedweb.pppl.gov/default.html ] exhausted, this brief, spectacular, closing phase of a Sun-like star's life [ http://plabpc.csustan.edu/astro/stars/stars.htm ] occurs as its outer layers are ejected - its core becoming a cooling, fading White Dwarf [ http://antwrp.gsfc.nasa.gov/apod/ap950910.html ]. Astronomers have recently used the Hubble Space Telescope [ http://antwrp.gsfc.nasa.gov/apod/ap950810.html ] (HST) to make a series of images of planetary nebulae [ http://antwrp.gsfc.nasa.gov/apod/ap950729.html ], including the one above [ http://www.stsci.edu/pubinfo/PR/96/07.html ]. Here, delicate rings of colorful glowing gas (nitrogen-red, hydrogen-green, and oxygen-blue) outline the tenuous walls of the "hourglass". The unprecedented sharpness of the HST images has revealed surprising details [ http://www.stsci.edu/pubinfo/gif/Hourgls.txt ] of the nebula ejection process [ http://antwrp.gsfc.nasa.gov/apod/ap960117.html ] and may help resolve the outstanding mystery of the variety of complex shapes and symmetries of planetary nebulae [ http://antwrp.gsfc.nasa.gov/apod/lib/planetary.html ].
Anatomy of a Shooting Star
PIA09959
Ultraviolet/Visible Camera
Title
Anatomy of a Shooting Star
Original Caption Released with Image
Annotated Version A close-up view of a star racing through space faster than a speeding bullet can be seen in this image from NASA's Galaxy Evolution Explorer. The star, called Mira (pronounced My-rah), is traveling at 130 kilometers per second, or 291,000 miles per hour. As it hurls along, it sheds material that will be recycled into new stars, planets and possibly even life. In this image, Mira is moving from left to right. It is visible as the pinkish dot in the bulb shape at right. The yellow dot below is a foreground star. Mira is traveling so fast that it's creating a bow shock, or build-up of gas, in front of it, as can be seen here at right. Like a boat traveling through water, a bow shock forms ahead of the star in the direction of its motion. Gas in the bow shock is heated and then mixes with the cool hydrogen gas in the wind that is blowing off Mira. This heated hydrogen gas then flows around behind the star, forming a wake. Why is the wake of material glowing? When the hydrogen gas is heated, it transitions into a higher-energy state, which then loses energy by emitting ultraviolet light - a process called fluorescence. The Galaxy Evolution Explorer has special instruments that can detect this ultraviolet light. A similar fluorescence process is responsible for the Northern Lights -- a glowing, green aurora that can be seen from northern latitudes. However, in that case nitrogen and oxygen gas are fluorescing with visible light. Streams and a loop of material can also be seen coming off Mira. Astronomers are still investigating what these streams are, but they suspect that they are denser parts of Mira's wind perhaps flowing out of the star's poles. This image consists of data captured by both the far- and near-ultraviolet detectors on the Galaxy Evolution Explorer between November 18 and December 15, 2006. It has a total exposure time of about 3 hours.
Galaxy Evolution Explorer Sp
PIA09653
Far-ultraviolet Detector, Ne
Title
Galaxy Evolution Explorer Spies Band of Stars
Original Caption Released with Image
The Galaxy Evolution Explorer's ultraviolet eyes have captured a globular star cluster, called NGC 362, in our own Milky Way galaxy. In this new image, the cluster appears next to stars from a more distant neighboring galaxy, known as the Small Magellanic Cloud. Globular clusters are densely packed bunches of old stars scattered in galaxies throughout the universe. NGC 362, located 30,000 light-years away, can be spotted as the dense collection of mostly yellow-tinted stars surrounding a large white-yellow spot toward the top-right of this image. The white spot is actually the core of the cluster, which is made up of stars so closely packed together that the Galaxy Evolution Explorer cannot see them individually. The light blue dots surrounding the cluster core are called extreme horizontal branch stars. These stars used to be very similar to our sun and are nearing the end of their lives. They are very hot, with temperatures reaching up to about four times that of the surface of our sun (25,000 Kelvin or 45,500 degrees Fahrenheit). A star like our sun spends most of its life fusing hydrogen atoms in its core into helium. When the star runs out of hydrogen in its core, its outer envelope will expand. The star then becomes a red giant, which burns hydrogen in a shell surrounding its inner core. Throughout its life as a red giant, the star loses a lot of mass, then begins to burn helium at its core. Some stars will have lost so much mass at the end of this process, up to 85 percent of their envelopes, that most of the envelope is gone. What is left is a very hot ultraviolet-bright core, or extreme horizontal branch star. Blue dots scattered throughout the image are hot, young stars in the Small Magellanic Cloud, a satellite galaxy of the Milky Way located approximately 200,000 light-years away. The stars in this galaxy are much brighter intrinsically than extreme horizontal branch stars, but they appear just as bright because they are farther away. The blue stars in the Small Magellanic Cloud are only about a few tens of millions of years old, much younger than the approximately 10-million-year-old stars in NGC 362. Because NGC 362 sits on the northern edge of the Small Magellanic Cloud galaxy, the blue stars are denser toward the south, or bottom, of the image. Some of the yellow spots in this image are stars in the Milky Way galaxy that are along this line of sight. Astronomers believe that some of the other spots, particularly those closer to NGC 362, might actually be a relatively ultraviolet-dim family of stars called "blue stragglers." These stars are formed from collisions or close encounters between two closely orbiting stars in a globular cluster. This image is a false-color composite, where light detected by the Galaxy Evolution Explorer's far-ultraviolet detector is colored blue, and light from the telescope's near-ultraviolet detector is red.
Meteor Search by Spirit, Sol
PIA03613
Sol (our sun)
Panoramic Camera
Title
Meteor Search by Spirit, Sol 643
Original Caption Released with Image
, and Selsis et al. (2005) Nature, vol 435, p. 581). On Earth, some meteors come in "storms" or "showers" at predictable times of the year, like the famous Perseid meteor shower in August or the Leonid meteor shower in November. These "storms" happen when Earth passes through the same parts of space where comets sometimes pass. The meteors we see at these times are from leftover debris that was shed off of these comets. The same kind of thing is predicted for Mars, as well. Inspired by calculations about Martian meteor storms by meteor scientists from the University of Western Ontario in Canada and the Centre de Recherche en Astrophysique de Lyon in France, and also aided by other meteor research colleagues from NASA's Marshall Space Flight Center, scientists on the rover team planned some observations to try to detect predicted meteor storms in October and November, 2005. The views shown here are a composite of nine 60-second exposures taken with the panoramic camera on Spirit during night hours of sol 643 (Oct. 25, 2005), during a week when Mars was predicted to pass through a meteor stream associated with comet P/2001R1 LONEOS. Many stars can be seen in the images, appearing as curved "dash-dot" streaks. The star trails are curved because Mars is rotating while the camera takes the images. The dash-dot pattern is an artifact of taking an image for 60 seconds, then pausing about 10 seconds while the image is processed and stored by the rover's computer, then taking another image for 60 seconds, etc., for a total of about 10 minutes worth of "staring" at the night sky. Many stars from the southern constellations Octans and Pavonis can be seen in the images. The brightest ones in this view would be easily visible to the naked eye, but the faintest ones are slightly dimmer than the human eye can detect. In addition to the star trails, there are several smaller linear streaks, dots and splotches that are the trails left by cosmic rays hitting the camera detectors. Cosmic rays are high-energy particles that are created in the Sun and in other stars throughout our galaxy and travel through space in all directions. Some of them strike Earth or other planets, and ones that strike a digital camera detector can leave little tracks or splotches like those seen in these images. Because they come from all directions, some strike the detector face-on, and others strike at glancing angles. Some even skip across the detector like flat rocks skipped across a pond. These are very common phenomena to astronomers used to working with sensitive digital cameras like those in the Mars rovers, the Hubble Space Telescope, or other space probes, and while they can be a nuisance when taking pictures, they generally do not cause any lasting damage to the cameras. One streak in the image, crossing at an angle very different from the direction of the stars'"motion," might be a meteor trail or could be the mark of another cosmic ray. While hunting for meteors on Mars, Annotated Meteor Search by Spirit, Sol 643 The panoramic cameras on NASA's Mars Exploration Rovers are about as sensitive as the human eye at night. The cameras can see the same bright stars that we can see from Earth, and the same patterns of constellations dot the night sky. Scientists on the rover team have been taking images of some of these bright stars as part of several different projects. One project is designed to try to capture "shooting stars," or meteors, in the Martian night sky. "Meteoroids" are small pieces of comets and asteroids that travel through space and eventually run into a planet. On Earth, we can sometimes see meteoroids become brilliant, long "meteors" streaking across the night sky as they burn up from the friction in our atmosphere. Some of these meteors survive their fiery flight and land on the surface (or in the ocean) where, if found, they are called "meteorites." The same thing happens in the Martian atmosphere, and Spirit even accidentally discovered a meteor while attempting to obtain images of Earth in the pre-dawn sky back in March, 2004 (see http://marsrovers.jpl.nasa.gov/gallery/press/spirit/20040311a.html [ http://marsrovers.jpl.nasa.gov/gallery/press/spirit/20040311a.html ], is fun, ultimately the team wants to use the images and results for scientific purposes. These include helping to validate the models and predictions for interplanetary meteor storms, providing information on the rate of impacts of small meteoroids with Mars for comparison with rates for the Earth and Moon, assessing the rate and intensity of cosmic ray impact events in the Martian environment, and looking at whether some bright stars are being dimmed occasionally by water ice or dust clouds occurring at night during different Martian seasons.
Spinning Top Star
Title
Spinning Top Star
Description
A rare, infrared view of a developing star and its flaring jets taken by NASA's Spitzer Space Telescope (right) shows us what our own solar system might have looked like billions of years ago. In visible light, this star and its surrounding regions are completely hidden in darkness (left). Stars form out of spinning clouds, or envelopes, of gas and dust. As the envelopes flatten and collapse, jets of gas stream outward and a swirling disk of planet-forming material takes shape around the forming star. Eventually, the envelope and jets disappear, leaving a newborn star with a suite of planets. This process takes millions of years. The Spitzer image shows a developing sun-like star, called L1157, that is only thousands of years old (for comparison, our solar system is around 4.5 billion years old). Why is the young system only visible in infrared light? The answer has to do with the fact that stars are born in the darkest and dustiest corners of space, where little visible light can escape. But the heat, or infrared light, of an object can be detected through the dust. In Spitzer's infrared view of L1157, the star itself is hidden but its envelope is visible in silhouette as a thick black bar. While Spitzer can peer through this region's dust, it cannot penetrate the envelope itself. Hence, the envelope appears black. The thickest part of the envelope can be seen as the black line crossing the giant jets. This L1157 portrait provides the first clear look at stellar envelope that has begun to flatten. The color white shows the hottest parts of the jets, with temperatures around 100 degrees Celsius (212 degrees Fahrenheit). Most of the material in the jets, seen in orange, is roughly zero degrees on the Celsius and Fahrenheit scales. The reddish haze all around the picture is dust. The white dots are other stars, mostly in the background. L1157 is located 800 light-years away in the constellation Cepheus. The Spitzer image was taken by the telescope's infrared array camera. Infrared light of 8 microns is colored red, 4.5-micron infrared light is green, and 3.6-micron infrared light is blue. The visible-light picture is from the Palomar Observatory-Space Telescope Science Institute Digitized Sky Survey. Blue visible light is blue, red visible light is green, and near-infrared light is red.
Spectrum of the newly-discov
2/18/00
Date
2/18/00
Description
Spectrum of the newly-discovered distant quasar, RD J030117+002025, obtained with the Keck Telescope atop Mauna Kea in Hawaii. The spectrum represents a 4.5 hour exposure, and shows how bright the quasar is as a function of wavelength, or color. Redder light is to the right. The primary feature of the spectrum are sharp ledges due to hydrogen absorption from gas clouds in the distant Universe. These absorptions cause the quasar to appear very red in images.
Ultra-cool Diminutive Star W
Title
Ultra-cool Diminutive Star Weighs In
General Information
What is a News Nugget? News Nuggets are bulletins from the world of astronomy. The power of the some of the world's biggest telescopes has been brought to bear to directly measure the mass, for the first time, of one of the smallest stars ever seen in the universe. Barely the size of the planet Jupiter, the dwarf star weighs in at just 8.5 percent of the mass of our Sun. Read more: * Release Text [ http://hubblesite.org/newscenter/archive/releases/2004/51/text/ ]
Comet Hale-Bopp Over Val Par
Title
Comet Hale-Bopp Over Val Parola Pass
Explanation
Comet Hale-Bopp became much brighter than any surrounding stars. It was seen even over bright city lights [ http://antwrp.gsfc.nasa.gov/apod/ap970408.html ]. Out away from city lights, however, it put on quite a spectacular show. Here Comet Hale-Bopp was photographed above Val Parola Pass in the Dolomite mountains [ http://www.geocities.com/Yosemite/Trails/6876/ ] surrounding Cortina d'Ampezzo [ http://www.sunrise.it/cortina/ ], Italy [ http://www.cia.gov/cia/publications/factbook/geos/it.html ]. Comet Hale-Bopp's blue ion tail was created when fast moving particles from the solar wind [ http://antwrp.gsfc.nasa.gov/apod/ap000318.html ] struck expelled ions from the comet's nucleus [ http://antwrp.gsfc.nasa.gov/apod/ap000805.html ]. The white dust tail [ http://antwrp.gsfc.nasa.gov/apod/ap001227.html ] is composed of larger particles of dust and ice expelled by the nucleus that orbit behind the comet [ http://www.nineplanets.org/comets.html ]. Observations showed that Comet Hale-Bopp's nucleus spins about once every 12 hours.
Comet Hale-Bopp observed by
Description
Comet Hale-Bopp observed by SOHO/SWAN on April 3, 1997. SOHO looks at a comet's shadow in space Depicted here is a series of three images of Comet Hale-Bopp's shadow taken by SOHO's SWAN instrument between 25 February, 1997 and 8 March, 1997. The blue-white monochrome images show a portion of the sky illuminated by the Sun's ultraviolet light. The Sun is shown as a round dot at the bottom. The bright white glow at the centre is a 150-million-kilometre-wide hydrogen cloud released by Hale-Bopp's nucleus. As the comet neared the Sun, the water-ice nucleus began to vaporize. Ultraviolet radiation then split the water molecules, which freed the hydrogen. The resulting hydrogen cloud absorbed the ultraviolet light emitted by the Sun, which was no longer available to illuminate the background of interstellar hydrogen. That resulted in an elongated, 150-million-kilometre-long shadow of the comet projected in sky, which is visible in the upper part of each image. The comet's movement in the sky (right to left) is evident by looking at the blue three-image sequence. The image bottom left is a schematic that depicts the geometry of the SWAN observations
Hale-Bopp and the North Amer
Title
Hale-Bopp and the North American Nebula
Explanation
Comet Hale-Bopp [ http://galileo.ivv.nasa.gov/comet/ ]'s recent encounter with the inner Solar System [ http://antwrp.gsfc.nasa.gov/apod/ap961214.html ] allowed many breath-taking pictures. Above, Comet Hale-Bopp [ http://encke.jpl.nasa.gov/hale_bopp_info.html ] was photographed on March 8th in the constellation of Cygnus [ http://astro.gmu.edu/constellation/CYG.html ]. Visible on the right in red is the North American Nebula [ http://antwrp.gsfc.nasa.gov/apod/ap960606.html ], a bright emission nebula [ http://antwrp.gsfc.nasa.gov/apod/lib/glossary.html#emis_neb ] observable from a dark location with binoculars. The North American Nebula [ http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1989A%26A%2E%2E%2E222%2E%2E%2E82S&db_key=AST&nosetcookie=1 ] is about 1500 light years away, much farther than the comet, which was about 8 light minutes away. Several bright blue stars from the open cluster [ http://antwrp.gsfc.nasa.gov/apod/ap970128.html ] M39 are visible just above the comet's blue ion tail [ http://antwrp.gsfc.nasa.gov/apod/ap960502.html ].
The (Almost) Invisible After
Title
The (Almost) Invisible Aftermath of a Massive Star's Death
Description
For the universe's biggest stars, even death is a show. Massive stars typically end their lives in explosive cataclysms, or supernovae, flinging abundant amounts of hot gas and radiation into outer space. Remnants of these dramatic deaths can linger for thousands of years and be easily detected by professional astronomers. However, not all stars like attention. Thirty thousand light-years away in the Cepheus constellation, astronomers think they've found a massive star whose death barely made a peep. Remnants of this shy star's supernova would have gone completely unnoticed if the super-sensitive eyes of NASA's Spitzer Space Telescope hadn't accidentally stumbled upon it. These three panels illustrate just how shy this star is. Unlike most supernova remnants, which are detectable at a variety of wavelengths ranging from radio to X-rays, this source only shows up in mid-infrared images taken by Spitzer's Multiband Imaging Photometer (MIPS). The remnant can be seen as a red-orange blob at the center of the picture. Although the visible-light (left) and near-infrared (middle) images capture the exact same region of space, the source is completely invisible in both pictures. Astronomers suspect that the remnant's elusiveness is due to its location away from our Milky Way galaxy's dusty main disk, which contains most of the galaxy's stars. A supernova is most noticeable when the material expelled during the star's furious death throes violently collides with surrounding dust. Since the shy star sits away from the galaxy's dusty and crowded disk, the hot gas and radiation it flung into space had little surrounding material to crash into. Thus, it is largely invisible at most wavelengths. MIPS did not need dust to see the remnant. The mid-infrared instrument was able to directly detect the oxygen-rich gas from the supernova's explosive death throes. The visible-light (left) image is a three-color composite of data from the California Institute of Technology's Digitized Sky Survey. In this image, light with a wavelength of 0.44 microns is represented as blue, 0.55-micron light is green, and 0.9-micron light is red. The near-infrared (middle) image is a two-color composite of data from Spitzer's infrared array camera. In this image, starlight captured at 4.5 microns is represented in blue, and 8-micron light from dust is green. The far-infrared image (right) combines the infrared array camera data with the multiband imaging photometer data, which show light of 24 microns in red.
Hubble Spies Shells of Spark
Title
Hubble Spies Shells of Sparkling Stars Around Quasar
Dissection of a Galaxy
Title
Dissection of a Galaxy
Description
Sometimes, the best way to understand how something works is to take it apart. The same is true for galaxies like NGC 300, which NASA's Spitzer Space Telescope has divided into its various parts. NGC 300 is a face-on spiral galaxy located 7.5 million light-years away in the southern constellation Sculptor. This false-color image taken by the infrared array camera on Spitzer readily distinguishes the main star component of the galaxy (blue) from its dusty spiral arms (red). The star distribution peaks strongly in the central bulge where older stars congregate, and tapers off along the arms where younger stars reside. Thanks to Spitzer's unique ability to sense the heat or infrared emission from dust, astronomers can now clearly trace the embedded dust structures within NGC 300's arms. When viewed at visible wavelengths, the galaxy's dust appears as dark lanes, largely overwhelmed by bright starlight. With Spitzer, the dust -- in particular organic compounds called polycyclic aromatic hydrocarbons -- can be seen in vivid detail (red). These organic molecules are produced, along with heavy elements, by the stellar nurseries that pepper the arms. The findings provide a better understanding of spiral galaxy mechanics and, in the future, will help decipher more distant galaxies, whose individual components cannot be resolved. This image was taken on Nov. 21, 2003 and is composed of photographs obtained at four wavelengths: 3.6 microns (blue), 4.5 microns (green), 5.8 microns (orange) and 8 microns (red).
Infrared Detective to the Re
Title
Infrared Detective to the Rescue
Description
In a collaborative effort between NASA's three Great Observatories, astronomers have solved a cosmic mystery by identifying some of the oldest and most distant black holes. The two rows of this image show two patches of sky, both contained within the field known as the Great Observatories Origins Deep Survey, or GOODS. In the first column, observations from the Chandra X-ray Observatory show high-energy emissions believed to trace the presence of supermassive black holes, which power the bright cores of distant galaxies. The mystery emerges in the second column. While most of the black hole candidates observed by Chandra could easily be identified within host galaxies seen by NASA's Hubble Space Telescope, several of them, like the two pictured here, showed no sign of a galaxy in visible light. The images in the third column, from NASA's Spitzer Space Telescope, show the same region in infrared light. In these images, the otherwise invisible galaxies reappear. These unusually "reddened" objects may be shrouded in dense clouds of obscuring dust, or may be remarkably distant compared to other galaxies in the same field. Additional Spitzer observations later this year should help astronomers determine the nature of these unusual objects.
Stellar 'Incubators' Seen Co
Title
Stellar 'Incubators' Seen Cooking up Stars
Description
This image composite compares visible-light and infrared views from NASA's Spitzer Space Telescope of the glowing Trifid Nebula, a giant star-forming cloud of gas and dust located 5,400 light-years away in the constellation Sagittarius. Visible-light images of the Trifid taken with NASA's Hubble Space Telescope, Baltimore, Md. (inside left) and the National Optical Astronomy Observatory, Tucson, Ariz., (outside left) show a murky cloud lined with dark trails of dust. Data of this same region from the Institute for Radioastronomy millimeter telescope in Spain revealed four dense knots, or cores, of dust (outlined by yellow circles), which are "incubators" for embryonic stars. Astronomers thought these cores were not yet ripe for stars, until Spitzer spotted the warmth of rapidly growing massive embryos tucked inside. These embryos are indicated with arrows in the false-color Spitzer picture (right), taken by the telescope's infrared array camera. The same embryos cannot be seen in the visible-light pictures (left). Spitzer found clusters of embryos in two of the cores and only single embryos in the other two. This is one of the first times that multiple embryos have been observed in individual cores at this early stage of stellar development.