Asteroid 1999 RQ36

These series of radar images of asteroid 1999 RQ36 were obtained by NASA's Deep Space Network antenna in Goldstone, California on September 23, 1999.

NASA detects, tracks and characterizes asteroids and comets passing close to Earth using both ground- and space-based telescopes. The Near-Earth Object Observations Program at NASA's Jet Propulsion Laboratory in Pasadena, California, commonly called "Spaceguard," discovers these objects, characterizes some of them, and plots their orbits to determine if any could be potentially hazardous to our planet.

Image credit: NASA/JPL-Caltech

Note: For more information, see NASA Scientist Figures Way to Weigh Space Rock.

Dragon Flight

The Dragon commercial space ferry seen from the International Space Station during a demonstration of its maneuvering capabilities on 24 May 2012.

Once cleared for approach, Dragon stopped 10 m from the Space Station where ESA astronaut André Kuipers and NASA astronaut Don Pettit used a robotic arm to grab and dock the spacecraft.

Dragon brought supplies and equipment to the orbital outpost and will return to Earth a week later.

Photo credit: NASA/ESA

Note: Yes, the title to this post is intentional.

Messier 101, The Pinwheel Galaxy

This image of the Pinwheel Galaxy, or M101, combines data in the infrared, visible, ultraviolet and X-rays from four of NASA's space telescopes. The view shows that both young and old stars are evenly distributed along M101's tightly wound spiral arms. Such composite images allow astronomers to see how features in one part of the light spectrum match up with those seen in other parts. It's like seeing with a regular camera, an ultraviolet camera, night-vision goggles and X-ray vision, all at once!

The Pinwheel Galaxy is in the constellation of Ursa Major (also known as the Big Dipper). It is about 70 percent larger than our own Milky Way galaxy, with a diameter of about 170,000 light-years, and sits at a distance of 21 million light-years from Earth. This means that the light we're seeing in this image left the Pinwheel Galaxy about 21 million years ago -- many millions of years before humans ever walked the Earth.

The red colors in the image show infrared light, as seen by the Spitzer Space Telescope. These areas show the heat emitted by dusty lanes in the galaxy, where stars are forming.

The yellow component is visible light, observed by the Hubble Space Telescope. Most of this light comes from stars, and they trace the same spiral structure as the dust lanes seen in the infrared.

The blue areas show ultraviolet light, given out by hot, young stars that formed about 1 million years ago. The Galaxy Evolution Explorer, which NASA recently loaned to the California Institute of Technology in Pasadena, California, captured this component of the image.

Finally, the hottest areas are shown in purple, where the Chandra X-ray Observatory observed the X-ray emission from exploded stars, million-degree gas and material colliding around black holes.

Photo credit: NASA/JPL-Caltech/ESA/STScI/CXC

Note: For more information, see M101: A Pinwheel in Many Colors.

June 2004 Transit of Venus

The transit of Venus across the Sun as recorded by ESAC observers located in Portugal 8 June 2004.

Video credit: ESA

Note: For more information, see Get Ready for the Transit of Venus!

Mississippi River Delta

This Landsat image of 3 October 2011 shows the Mississippi River Delta, where the largest river in the United States empties into the Gulf of Mexico. In this false-color image, land vegetation appears pink, while the sediment in the surrounding waters are bright blue and green.

Photo credit: USGS/ESA

Possible Disintegration of a Planet Around KIC 12557548

This artist's concept depicts a comet-like tail of a possible disintegrating super Mercury-size planet candidate as it transits, or crosses, its parent star, named KIC 12557548. The results are based on data from NASA's Kepler mission.

At an orbital distance of only twice the diameter of its star, the surface temperature of the potential planet is estimated to be a sweltering 3,300 degrees Fahrenheit (1,816 degrees Celsius). At such a high temperature, the surface would melt and evaporate. The energy from the resulting wind would be enough to allow dust and gas to escape into space creating a trailing dusty effluence that intermittently blocks the starlight.

Illustration credit: NASA/JPL-Caltech

Note: For more information, see NASA's Kepler Detects Potential Evaporating Planet.

A Brief Interlude

The Minister is recovering from some minor surgery done a few days ago. He will resume posting as soon as he is able.

CW Leo by Galex

A runaway star, plowing through the depths of space and piling up interstellar material before it, can be seen in this ultraviolet image from NASA's Galaxy Evolution Explorer. The star, called CW Leo, is hurtling through space at about 204,000 miles per hour (91 kilometers per second), or roughly 265 times the speed of sound on Earth. It is shedding its own atmosphere to form a sooty shell of discarded material. This shell can be seen in the center of this image as a bright circular blob.

CW Leo is moving from right to left in this image. It is traveling so quickly through the surrounding material that it has formed a semi-circular bow shock in front of itself, like a boat moving through water. This bow shock is made of superheated gas, which flows around the star and is left behind in its turbulent wake. This blown-out bubble is 2.7 light-years across, which is more than half the distance from our Sun to the nearest star, or 2,100 times the size of Pluto's orbit.

The size of the bubble (called the "astrosheath") has allowed astronomers to estimate that CW Leo has been shedding its atmosphere for about 70,000 years. This is part of the star's natural life cycle as it runs out of hydrogen fuel and gradually throws off its outer layers to expose its bare, dying core. This core is called a white dwarf, and is the end product of all low-mass stars like our Sun.

CW Leo is the second runaway star to be observed with the Galaxy Evolution Explorer. The first, Mira, was observed by the telescope back in 2006.

This image is the combination of near-ultraviolet data, shown in yellow, and far-ultraviolet data, shown in blue.

Photo credit: NASA/JPL-Caltech

Notes: Due to the size of the jpg file (8.4 mb), the Minister has substituted a much smaller version of the image for the normal-size picture. The full-size jpg file may be found here. For more recent news about Galex, see NASA Lends Galaxy Evolution Explorer to Caltech.

Messier 31, the Andromeda Galaxy in Ultraviolet

Hot stars burn brightly in this new image from NASA's Galaxy Evolution Explorer, showing the ultraviolet side of a familiar face.

At approximately 2.5 million light-years away, the Andromeda galaxy, or M31, is our Milky Way's largest galactic neighbor. The entire galaxy spans 260,000 light-years across -- a distance so large, it took 11 different image segments stitched together to produce this view of the galaxy next door.

The bands of blue-white making up the galaxy's striking rings are neighborhoods that harbor hot, young, massive stars. Dark blue-grey lanes of cooler dust show up starkly against these bright rings, tracing the regions where star formation is currently taking place in dense cloudy cocoons. Eventually, these dusty lanes will be blown away by strong stellar winds, as the forming stars ignite nuclear fusion in their cores. Meanwhile, the central orange-white ball reveals a congregation of cooler, old stars that formed long ago.

When observed in visible light, Andromeda's rings look more like spiral arms. The ultraviolet view shows that these arms more closely resemble the ring-like structure previously observed in infrared wavelengths with NASA's Spitzer Space Telescope. Astronomers using Spitzer interpreted these rings as evidence that the galaxy was involved in a direct collision with its neighbor, M32, more than 200 million years ago.

Andromeda is so bright and close to us that it is one of only ten galaxies that can be spotted from Earth with the naked eye. This view is two-color composite, where blue represents far-ultraviolet light, and orange is near-ultraviolet light.

Photo credit: NASA/JPL-Caltech

Note: For more recent news about Galex, see NASA Lends Galaxy Evolution Explorer to Caltech.

NGC 7293 - The Helix Nebula - In Ultraviolet

NGC 7293, better known as the Helix nebula, displays its ultraviolet glow courtesy of NASA's Galaxy Evolution Explorer (GALEX). The Helix is the nearest example of a planetary nebula, which is the eventual fate of a star, like our own Sun, as it approaches the end of its life. As it runs out of fuel, the star expels its outer envelope of gas outward to form a nebula like the Helix. The remaining core of the star is a small, hot, dense remnant known as a white dwarf.

Photo credit: NASA/JPL-Caltech

Note: For more recent news about Galex, see NASA Lends Galaxy Evolution Explorer to Caltech.

Massive Star Formation in an Intergalactic Filament

The Herschel Space Observatory has discovered a giant, galaxy-packed filament ablaze with billions of new stars. The filament connects two clusters of galaxies that, along with a third cluster, will smash together in several billion years and give rise to one of the largest galaxy superclusters in the universe.

The three galaxy clusters of the emerging supercluster, known as RCS2319, are seen in visible and X-ray light (purple) to the left. Observations by Herschel in infrared light appear to the right, with colored regions indicating greater infrared emissions. A white circle broadly outlines the 8 million light-year-long intergalactic filament in each image.

In visible light, the filament does not stand out because dust obscures the star-formation activity in distant galaxies. Telescopes like Herschel, however, can detect the infrared glow of this dust as it is heated by newborn stars.

The amount of infrared light suggests that the galaxies in the filament are cranking out the equivalent of about 1,000 new Suns in terms of mass per year. For comparison's sake, our Milky Way galaxy is producing about one Sun's mass-worth of new stars per year.

Notably, the third galaxy cluster is off the edge of the image on the right. The reason behind this apparent snub is that the original research proposal called for making a map centered on the top cluster. During the observing run, astronomers did not know the filament existed, so its eventual discovery serves as a nice example of scientific serendipity. The team is now aiming to perform further follow-up observations to examine the filament in more detail.

Photo credit: ESA/NASA/JPL-Caltech/CXC/McGill University

Note: For more information, see Herschel Sees Intergalactic Bridge Aglow With Stars.

Radar Map of Venus

This map of the surface of Venus was created from observations accumulated during more than a decade of radar imaging of the planet. Observations made by NASA's Magellan spacecraft between 1990 and 1994 form the base of the image, with gaps in the data filled in by the Arecibo Observatory, which is based in Puerto Rico. The image is color-coded to show elevation, using information gathered by the Magellan radar altimeter, with additional data provided by the Soviet Venera spacecraft and NASA’s Pioneer Venus missions.

Radar images of Venus have revealed geological structures on the planet, such as steep-sided domes and rugged highland terrain, which geologists think could feature mineral-rich materials, such as felsic rocks.

The discovery of felsic rocks on Venus would add support to the idea that the planet was once more Earth-like, as most of these materials on Earth formed in a water environment. However, other processes that don’t require the presence of water may also produce felsic rocks.

Map credit: NASA/JPL/USGS

Note: This particular view of Venus is centered on 270° East. For more information about this story, see Venus Express Unearths New Clues to the Planet's Geological History

SN 2010JL

SN 2010jl: A supernova found in the galaxy UGC 5189A about 160 million light years from Earth.

This composite image shows the galaxy UGC 5189A in X-ray data from Chandra (purple) and optical data from Hubble (red, green and blue.) The very bright source near the top of the galaxy is SN 2010jl, a recently discovered supernova. Data from Chandra have provided the first X-ray evidence of a supernova shock wave breaking through a cocoon of gas surrounding the star that exploded in SN 2010jl. This discovery may help astronomers understand why some supernovas are much more powerful than others.

Scale: Image is 46 arcsec across. (36,000 light years across.)

Photo credits: X-ray: NASA/CXC/Royal Military College of Canada/P.Chandra et al); Optical: NASA/STScI

Notes: For more information, see SN 2010jl: A Supernova Cocoon Breakthrough. Also, the second link for UGC 5189A is in the German language. The Minister does not normally link to non-English language websites, but the translation of this webpage provides information on this galaxy that is not available in the other links.

Deep Field of Centaurus A

The peculiar galaxy Centaurus A (NGC 5128) is pictured in this image taken with by the Wide Field Imager attached to the MPG/ESO 2.2-meter telescope at the La Silla Observatory in Chile. With a total exposure time of more than 50 hours this is probably the deepest view of this peculiar and spectacular object ever created.

Photo credit: ESO

Note: For more information, see A Deeper Look at Centaurus A.

Golden Night on Saturn

Saturn's B and C rings shine in diffuse, scattered light as the Cassini spacecraft looks on the planet's night side. The southern hemisphere is lit by sunlight reflecting off the rings, while the north shines much more feebly in the dim light that filters through the rings and is scattered on the northern hemisphere.

The fine, innermost rings are seen silhouetted against the southern hemisphere of the planet before partially disappearing into shadow.

The color of the rings appears more golden because of the increased scattering in the rings brought about by the high phase angle and the view being toward rings' the unlit side. Saturn also looks more golden because of the high phase angle here.

Images taken using red, green and blue spectral filters were combined to create this natural color view. The images were obtained by the Cassini spacecraft wide-angle camera on September 28, 2006 at a distance of approximately 1.4 million kilometers (900,000 miles) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 151 degrees. Image scale is 83 kilometers (51 miles) per pixel.

Photo credit: NASA/JPL/Space Science Institute

NGC 2366

The NASA/ESA Hubble Space Telescope has made detailed observations of the dwarf galaxy NGC 2366. While it lacks the elegant spiral arms of many larger galaxies, NGC 2366 is home to a bright, star-forming nebula and is close enough for astronomers to discern its individual stars.

Photo credit: NASA/ESA

Note: For more information, see Hubble Observes a Dwarf Galaxy With a Bright Nebula.

Cygnus X

This new view of the Cygnus-X star-formation region by Herschel highlights chaotic networks of dust and gas that point to sites of massive star formation.

The image combines data acquired with the PACS instrument at 70 micron (corresponding to the blue channel) and 160 micron (corresponding to the green channel) and with the SPIRE instrument at 250 micron (corresponding to the red channel). The observations were made on 24 May 2010 and 18 December 2010. North is to the lower-right and east to the upper-right.

Photo credit: ESA/PACS/SPIRE/Martin Hennemann & Frédérique Motte, Laboratoire AIM Paris-Saclay, CEA/Irfu – CNRS/INSU – Univ. Paris Diderot, France

Note: For more information, including an annotated version of the above image, see How Massive Stars Sculpt a Cosmic Crib. Also, PIA15626: Cygnus-X: The Cool Swan Glowing in Flight.

Vesta's Snowman Craters in Color

Three impact craters of different sizes, arranged in the shape of a snowman, make up one of the most striking features on Vesta, as seen in this view from NASA's Dawn mission. In this view the three "snowballs" are upside down, so that the shadows make the features easily recognizable. North is to the lower right in the image, which has a resolution of 230 feet (70 meters) per pixel.

The image is composed of many individual photographs taken between October and December 2011 by Dawn's framing camera. They were obtained during the high-altitude mapping orbit, at about 420 miles (680 kilometers) above Vesta's surface.

The largest of the three craters, Marcia, has a diameter of about 40 miles (60 kilometers). The central crater, which is about 30 miles (50 kilometers) in diameter, is named Calpurnia, and the lower crater, named Minucia, has a diameter of about 14 miles (22 kilometers). Marcia and Calpurnia are possibly the result of an impact by doublet asteroids, whereas Minucia was formed by a later impact.

To derive the color information, scientists combined images acquired by the framing camera in two near-infrared channels (0.917 microns and 0.749 microns) and an ultraviolet channel (0.438 microns). The true colors of the surface of Vesta differ somewhat from what is displayed here, but this mode of reproduction allows subtle changes in material properties across the craters and material ejected from impacts to be detected. In both Marcia and Calpurnia, landslides can be seen; also, dark material has been exposed below the rim of Marcia.

Photo credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

Active Black Hole Squashes Star Formation

The Herschel Space Observatory has shown that galaxies with the most powerful, active, supermassive black holes at their cores produce fewer stars than galaxies with less active black holes.

Supermassive black holes are believed to reside in the hearts of all large galaxies. When gas falls upon these monsters, the materials are accelerated and heated around the black hole, releasing great torrents of energy. In the process, active black holes often generate colossal jets that blast out twin streams of heated matter.

Inflows of gas into a galaxy also fuel the formation of new stars. In a new study of distant galaxies, Herschel helped show that star formation and black hole activity increase together, but only up to a point. Astronomers think that if an active black hole flares up too much, it starts spewing radiation that prevents raw material from coalescing into new stars.

This artistically modified image of the local galaxy Arp 220, captured by the Hubble Space Telescope, helps illustrate the Herschel results. The bright core of the galaxy, paired with an overlaid artist's impression of jets emanating from it, indicate that the central black hole's activity is intensifying. As the active black hole continues to rev up, the rate of star formation will, in turn, be tamped down in the galaxy. Astronomers want to further study how star formation and black hole activity are intertwined.

Illustration credit: NASA/JPL-Caltech

Note: This is one of this week's big stories. For more information, see:
* Overfed Black Holes Shut Down Galactic Star-Making
* The Most Powerful Black Holes Quenched Their Galaxy's Star Formation
* Herschel Galaxy Survey: Overfed Black Holes Shut Down Galactic Star-Making

Messier 55

This striking view of the globular star cluster Messier 55 in the constellation of Sagittarius (The Archer) was obtained in infrared light with the VISTA survey telescope at ESO’s Paranal Observatory in Chile. This vast ball of ancient stars is located at a distance of about 17,000 light-years from Earth.

Photo credit: ESO/J. Emerson/VISTA. Acknowledgment: Cambridge Astronomical Survey Unit

Note: For more information, see VISTA Views a Vast Ball of Stars.

55 Cancri e

NASA's Spitzer Space Telescope has, for the first time, captured the light emanating from a distant super Earth, a planet more massive than Earth but lighter than Neptune. Super Earths can be either rocky or gaseous. In this case, theorists propose that the planet, called 55 Cancri e, has a rocky core surrounded by a layer of water in a "supercritical" state, where it is both liquid and gas. Topping it all off is thought to be a blanket of steam. It's as if Neptune were somehow dragged closer to the Sun and stripped of its large atmosphere.

This artist's animation depicts 55 Cancri e as it orbits its star. The planet whips around the star closely and quickly: It is 25 times closer to the star than Mercury is to our Sun and completes one orbit -- its year -- in a mere 18 hours.

The view starts off showing the system in visible light then switches to show how Spitzer saw it in infrared light. In infrared, the planet stands out more relative to its star -- it is brighter when viewed in infrared light and the star is dimmer. This is partly because the planet's sizzling heat causes it to glow brightly at infrared wavelengths.

The planet is too close to its star to be seen separately on the sky, so Spitzer used a specialized trick to see its light. As the planet slipped behind the star in what is called an occultation, the infrared telescope observed how much the total light from the system dropped. The data are shown on a graph that appears in front of the star system.

By measuring the amount of total light before, during and after this drop, astronomers can then calculate how much light is coming directly from the planet itself. The information revealed that the planet's sun-facing side is more than a scorching 2,000 kelvins (3,140 degrees Fahrenheit), or hot enough to melt steel. The data also indicated that the planet does not reflect much visible light; in other words, it is very dark.

The observations are an important milestone in the search for life in the universe. NASA's upcoming James Webb Space Telescope will use a similar technique to probe the atmospheres of even smaller, potentially habitable planets for signs of life.

Video credit: NASA/JPL-Caltech; infographic credit: NASA/JPL-Caltech

Note: This is today's big story. For more information, see:
* NASA's Spitzer Sees the Light of Alien 'Super Earth'
* NASA Space Telescope Sees the Light from an Alien Super-Earth
* PIA15621: Magician of a Planet Disappears to Reveal Itself
* PIA15622: First-of-Its-Kind Glimpse at a Super Earth

Sharpless 140

In the quest to better understand the birth of stars and the formation of new worlds, astronomers have used NASA's Spitzer Space Telescope to examine the massive stars contained in a cloudy region called Sharpless 140. This cloud is a star-forming microcosm that exhibits, within a relatively small area, all of the classic manifestations of stellar birth.

Sharpless 140 lies almost 3,000 light-years from Earth in the constellation Cepheus. At its heart is a cluster of three deeply embedded young stars, which are each several thousand times brighter than the Sun. Though they are strikingly visible in this image from Spitzer's infrared array camera, they are completely obscured in visible light, buried within the core of the surrounding dust cloud.

The extreme youth of at least one of these stars is indicated by the presence of a stream of gas moving at high velocities. Such outflows are signatures of the processes surrounding a star that is still gobbling up material as part of its formation.

The bright red bowl, or arc, seen in this image traces the outer surface of the dense dust cloud encasing the young stars. This arc is made up primarily of organic compounds called polycyclic aromatic hydrocarbons, which glow on the surface of the cloud. Ultraviolet light from a nearby bright star outside of the image is "eating away" at these molecules. Eventually, this light will destroy the dust envelope and the masked young stars will emerge.

This false-color image was taken on October 11, 2003.

Photo credit: NASA/JPL-Caltech

Gemini 6 by Gemini 7

On December 4, 1965, NASA launched Gemini VII. With this mission, NASA successfully completed its first rendezvous of two spacecraft. This photograph, taken by Gemini VII crewmembers Jim Lovell and Frank Borman, shows Gemini VI in orbit 160 miles (257 km) above Earth. The main purpose of Gemini VI, crewed by astronauts Walter Schirra and Thomas Stafford, was the rendezvous with Gemini VII. The main purpose of Gemini VII, on the other hand, was studying the long-term effects of long-duration (up to 14 days) space flight on a two-man crew. The pair also carried out 20 experiments, including medical tests. Although the principal objectives of both missions differed, they were both carried out so that NASA could master the technical challenges of getting into and working in space.

Photo credit: NASA

The Egg Nebula

The NASA/ESA Hubble Space Telescope has been on the forefront of research into the lives of stars like our Sun. At the ends of their lives, these stars run out of nuclear fuel in a phase that is called the preplanetary or protoplanetary nebula stage. This Hubble image of the Egg Nebula shows one of the best views to date of this brief, but dramatic, phase in a star’s life.

During the preplanetary nebula phase, the hot remains of an aging star in the center of the nebula heat it up, excite the gas and make it glow over several thousand years. The short lifespan of preplanetary nebulae means there are relatively few of them in existence at any one time. Moreover, they are very dim, requiring powerful telescopes to be seen. This combination of rarity and faintness means they were only discovered comparatively recently. The Egg Nebula, the first to be discovered, was first spotted less than 40 years ago, and many aspects of this class of object remain shrouded in mystery.

At the center of this image, and hidden in a thick cloud of dust, is the nebula’s central star. While scientists can’t see the star directly, four searchlight beams of light coming from it shine out through the nebula. Researchers hypothesize that ring-shaped holes in the thick cocoon of dust, carved by jets coming from the star, let the beams of light emerge through the otherwise opaque cloud. The precise mechanism by which stellar jets produce these holes is not known, but one explanation is that a binary star system, rather than a single star, exists at the center of the nebula.

The onion-like layered structure of the more diffuse cloud surrounding the central cocoon is caused by periodic bursts of material being ejected from the dying star. The bursts typically occur every few hundred years.

This image is produced from exposures in visible and infrared light from Hubble’s Wide Field Camera 3.

Photo credit: ESA/Hubble, NASA

PS1-10jh

An extraordinary outburst produced by a black hole in a nearby galaxy has provided direct evidence for a population of old, volatile stellar black holes. The discovery, made by astronomers using data from NASA's Chandra X-ray Observatory, provides new insight into the nature of a mysterious class of black holes that can produce as much energy in X-rays as a million suns radiate at all wavelengths.

Researchers used Chandra to discover a new ultraluminous X-ray source, or ULX. These objects give off more X-rays than most binary systems, in which a companion star orbits the remains of a collapsed star. These collapsed stars form either a dense core called a neutron star or a black hole. The extra X-ray emission suggests ULXs contain black holes that might be much more massive than the ones found elsewhere in our galaxy.

A paper describing these results will appear in the May 10, 2012, issue of The Astrophysical Journal.

Photo credit: X-ray: NASA/CXC/Curtin University/R. Soria et al., Optical: NASA/STScI/ Middlebury College/F. Winkler et al.

Note: This post is related to yesterday's Black Hole Rips Apart a Star.

Black Hole Rips Apart a Star

PS1-10jh: A galaxy about 2.7 billion light years from Earth with a supermassive black hole at its center.

This computer-simulated image shows gas from a star that is ripped apart by tidal forces as it falls into a black hole. Some of the gas also is being ejected at high speeds into space. Observations from multiple telescopes, including NASA's Chandra X-ray Observatory, were used to determine the most direct evidence yet of a star being ripped apart by a supermassive black hole. Chandra's X-ray data were critical in ruling out the other contending possibility that this galaxy instead contained a so-called active galactic nucleus.

Illustration credit: NASA, S. Gezari (The Johns Hopkins University), and J. Guillochon (University of California, Santa Cruz); video credit: NASA, S. Gezari (The Johns Hopkins University), and J. Guillochon (University of California, Santa Cruz)

Note: This is the current big story. For more information, see PS1-10jh: Black Hole Caught Red-handed in a Stellar Homicide . Also, see:
* Black Hole Caught Red-Handed in a Stellar Homicide
* PIA15429: Black Hole Erupts
* PIA15620: Black Hole Swallows a Star

Topographic Map of Mercury's Northern Hemisphere

The Mercury Laser Altimeter (MLA) ranges at a wavelength of 1064 nm at an 8 Hz rate and illuminates Mercury's surface in spots between 15 and 100 m across, depending on the MESSENGER spacecraft's range. The MLA has so far returned 10.7 million precise measurements of the elevation of Mercury's northern hemisphere. Shown here is a polar stereographic projection of the topography of Mercury from the north pole to 5° S. The outlines of selected major impact structures are shown as black circles.

Map credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Messier 78

This image of the region surrounding the reflection nebula Messier 78, just to the north of Orion’s belt, shows clouds of cosmic dust threaded through the nebula like a string of pearls. The millimeter-wavelength observations, made with the Atacama Pathfinder Experiment (APEX) telescope and shown here in orange, use the heat glow of interstellar dust grains to show astronomers where new stars are being formed. They are overlaid on a view of the region in visible light.

Photo credit: ESO/APEX (MPIfR/ESO/OSO)/T. Stanke et al./Igor Chekalin/Digitized Sky Survey 2

Note: For more information, see Sifting Through Dust Near Orion's Belt.

ULX in Messier 83

M83: A spiral galaxy located about 15 million light years from Earth.

An extraordinary outburst from a black hole – where its X-ray output increased at least 3,000 times -- has been seen with NASA's Chandra X-ray Observatory in the galaxy M83. Chandra observed what is called a ULX, or ultraluminous X-ray source. The panel on the left features an optical view of the full M83 galaxy, while the right panel shows a close up of the region where the ULX was found with data from Chandra (pink) and Hubble (blue and yellow). The remarkable behavior of this ULX in M83 provides direct evidence for a population of older, volatile, stellar-mass black holes.

Scale: Left image: 17.6 arcmin on a side (~77,000 light years); Close-up: 0.6 x 1.2 arcmin (~2600 x ~5200 light years)

Photo credits: Left image - Optical: ESO/VLT; Close-up - X-ray: NASA/CXC/Curtin University/R.Soria et al., Optical: NASA/STScI/Middlebury College/F.Winkler et al.

Notes: For more information, see M83: A Remarkable Outburst from an Old Black Hole. For another spectacular image of this ULX, see Outburst.

NGC 2040

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, a dwarf satellite galaxy of the Milky Way. The image was captured by the NASA/ESA Hubble Space Telescope's Wide Field Planetary Camera 2.

The stellar grouping, known to stargazers as NGC 2040 or LH 88, is a loose star cluster whose stars have a common origin and are drifting together through space. There are three different types of stellar associations defined by their stellar properties. NGC 2040 is an OB association, a grouping that usually contains 10–100 stars of type O and B--these are high-mass stars that have short but brilliant lives. It is thought that most of the stars in the Milky Way were born in OB associations.

Photo credit: ESA/Hubble, NASA and D. A Gouliermis. Acknowledgement: Flickr user Eedresha Sturdivant