Behemoth Galaxy NGC 1275 portrayed by Hubble with the ACS

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The behemoth galaxy NGC 1275, also known as Perseus A, lies at the centre of the Perseus cluster of galaxies. NGC 1275 is an active galaxy well-known for its radio source (Perseus A) and is a strong emitter of X-rays due to the presence of the supermassive black hole in its centre. Hubble data from the Advanced Camera for Surveys covers visible-light wavelengths and is shown in the red, green and blue.
This Hubble Space Telescope image of galaxy NGC 1275 reveals the fine, thread-like filamentary structures in the gas surrounding the galaxy. The red filaments are composed of cool gas being suspended by a magnetic field, and are surrounded by the 100-million-degree Fahrenheit hot gas in the center of the Perseus galaxy cluster.
The filaments are dramatic markers of the feedback process through which energy is transferred from the central massive black hole to the surrounding gas. The filaments originate when cool gas is transported from the center of the galaxy by radio bubbles that rise in the hot interstellar gas.
At a distance of 230 million light-years, NGC 1275 is one of the closest giant elliptical galaxies.
The galaxy was photographed in July and August 2006 with Hubble's Advanced Camera for Surveys.
Credit: NASA, ESA, and the Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration
Acknowledgment: A. Fabian (Institute of Astronomy, University of Cambridge, UK)
Image enhancement: Jean-Baptiste Faure

Elaborate image of Saturn's moon Rhea by the Cassini spacecraft

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Hemispheric color differences on Saturn's moon Rhea are apparent in this false-color view from NASA's Cassini spacecraft. This image shows the side of the moon that always faces the planet.
In this image, the left half of the visible disk of Rhea faces in the direction of Rhea's orbital motion around Saturn, while the right side faces the trailing direction. It is not unusual for large icy Saturnian satellites to exhibit hemispheric albedo (reflectivity) and color differences. These differences are likely related to systematic regional changes in surface composition or the sizes and mechanical structure of grains making up the icy soil. Such large-scale variations can arise from numerous processes, such as meteoritic debris preferentially hitting one side of Rhea. The differences can also arise from "magnetic sweeping," a process that happens when ions that are trapped in Saturn's magnetic field drag over and implant themselves in Rhea's icy surface. The slightly reddish false-color hues near Rhea's poles identify subtle composition changes that might be caused by differences in the surface exposure to meteoric debris falling into the moon or implantation of ions. These differences could vary by latitude. They suggest that at least some of the color differences are exogenic, or derived externally.
This view was captured during Cassini's March 2, 2010 flyby of Rhea. To create the false-color view, ultraviolet, green and infrared images were combined into a single picture that isolates and maps regional color differences. This "color map" was then superimposed over a clear-filter image that preserves the relative brightness across the body.
This view looks toward the Saturn-facing side of Rhea (1528 kilometers, 949 miles across). North is up. The images were taken with the Cassini spacecraft wide-angle camera. The view was acquired at a distance of approximately 35,000 kilometers (22,000 miles) from Rhea and at a sun-Rhea-spacecraft, or phase, angle of 3 degrees. Image scale is 2 kilometers (1 mile) per pixel.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate in Washington. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging team is based at the Space Science Institute, Boulder, Colorado.
Credit: NASA/JPL/SSI

Hubble's picture of the Cartwheel Galaxy in tribute to the ST-ECF

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An image of the Cartwheel Galaxy taken with the NASA/ESA Hubble Space Telescope has been reprocessed using the latest techniques to mark the closure of the Space Telescope European Coordination Facility (ST-ECF), based near Munich in Germany, and to celebrate its achievements in supporting Hubble science in Europe over the past 26 years. Astronomer Bob Fosbury, who is stepping down as Head of the ST-ECF, was responsible for much of the early research into the Cartwheel Galaxy along with the late Tim Hawarden - including giving the object its very apposite name - and so this image was selected as a fitting tribute. The object was first spotted on wide-field images from the UK Schmidt telescope and then studied in detail using the Anglo-Australian Telescope. Lying about 500 million light-years away in the constellation of Sculptor, the cartwheel shape of this galaxy is the result of a violent galactic collision. A smaller galaxy has passed right through a large disc galaxy and produced shock waves that swept up gas and dust - much like the ripples produced when a stone is dropped into a lake - and sparked regions of intense star formation (appearing blue). The outermost ring of the galaxy, which is 1.5 times the size of our Milky Way, marks the shock wave's leading edge. This object is one of the most dramatic examples of the small class of ring galaxies. This image was produced after Hubble data was reprocessed using the free open source software FITS Liberator 3, which was developed at the ST-ECF. Careful use of this widely used state-of-the-art tool on the original Hubble observations of the Cartwheel Galaxy has brought out more detail in the image than ever before.
Credit: ESA/Hubble and NASA

The long tail of Stars of UGC 10214 as pictured by Hubble!

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Against a stunning backdrop of thousands of galaxies, this odd-looking galaxy with the long streamer of stars appears to be racing through space, like a runaway pinwheel firework. This picture of the galaxy UGC 10214 was taken by the Advanced Camera for Surveys (ACS), which was installed aboard the NASA/ESA Hubble Space Telescope during Servicing Mission 3B. Dubbed the "Tadpole", this spiral galaxy is unlike the textbook images of stately galaxies. Its distorted shape was caused by a small interloper, a very blue, compact, galaxy visible in the upper left corner of the more massive Tadpole. The Tadpole resides about 420 million light-years away in the constellation Draco. Seen shining through the Tadpole's disc, the tiny intruder is likely a hit and run galaxy that is now leaving the scene of the accident. Strong gravitational forces from the interaction created the long tail of stars and gas stretching out more than 280 000 light-years. Numerous young blue stars and star clusters, spawned by the galaxy collision, are seen in the spiral arms, as well as in the long "tidal" tail of stars. Each of these clusters represents the formation of up to about a million stars. Their colour is blue because they contain very massive stars, which are 10 times hotter and 1 million times brighter than our Sun. Once formed, the star clusters become redder with age as the most massive and bluest stars exhaust their fuel and burn out. These clusters will eventually become old globular clusters similar to those found in essentially all halos of galaxies, including our own Milky Way. Two prominent clumps of young bright blue stars are visible in the tidal tale and separated by a gap. These clumps of stars will likely become dwarf galaxies that orbit in the Tadpole's halo.
Behind the galactic carnage and torrent of star birth is another compelling picture: a "wallpaper pattern" of about 3000 faint galaxies. These galaxies represent twice the number of those found in the legendary Hubble Deep Field, the orbiting observatory's "deepest" view of the heavens, taken in 1995 by the Wide Field and Planetary Camera 2. The galaxies in the ACS picture, like those in the Hubble Deep Field, stretch back to nearly the beginning of time. They are a myriad of shapes and represent fossil samples of the Universe's 13-billion-year evolution.
The ACS picture was taken in one-twelfth the time it took to observe the Hubble Deep Field. In blue light, ACS discovered even fainter objects than those in the "deep field". The camera's vision is so sharp that astronomers can identify distant colliding galaxies, the "building blocks" of galaxies, an exquisite "Whitman's Sampler" of normal galaxies, and presumably extremely faraway galaxies. ACS made this observation on 1 and 9 April 2002. The colour image is constructed from three separate images taken in near-infrared, orange, and blue filters.
The full resolution image weighs 9.2 MB, so please be patient when downloading!
Credit: NASA, Holland Ford (JHU), the ACS Science Team and ESA

Apollo 8, the First Manned Mission to the Moon - Dec. 24, 1968

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Apollo 8, the first manned mission to the moon, entered lunar orbit on Christmas Eve, Dec. 24, 1968. That evening, the astronauts - Commander Frank Borman, Command Module Pilot Jim Lovell, and Lunar Module Pilot William Anders - held a live broadcast from lunar orbit, in which they showed pictures of the Earth and moon as seen from their spacecraft. Said Lovell, "The vast loneliness is awe-inspiring and it makes you realize just what you have back there on Earth." They ended the broadcast with the crew taking turns reading from the book of Genesis.
Credit: NASA
Image restoration: Jean-Baptiste Faure

Holiday wishes from the Hubble Space Telescope: M74 in high-res

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In this Hubble image of the galaxy M74 we can see a smattering of bright pink regions decorating the spiral arms. These are huge, relatively short-lived, clouds of hydrogen gas which glow due to the strong radiation from hot, young stars embedded within them; glowing pink regions of ionized hydrogen (hydrogen that has lost its electrons). These regions of star formation show an excess of light at ultraviolet wavelengths and astronomers call them HII regions.
The full resolution image weighs 12.0 MB, so please be patient when downloading!
Credit: NASA, ESA, and The Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration

NGC 1376 shows active star formation through Hubble's eyes

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A bluish-white spiral galaxy hangs delicately in the cold vacuum of space. Known as NGC 1376, this snowflake-shaped beauty was observed with the Hubble Space Telescope.
Concentrated along the spiral arms of NGC 1376, bright blue knots of glowing gas highlight areas of active star formation. These regions show an excess of light at ultraviolet (UV) wavelengths because they contain brilliant clusters of hot, newborn stars that are emitting UV light. The less intense, red areas near the core and between the arms consist mainly of older stars. The reddish dust lanes delineate cooler, denser regions where interstellar clouds may collapse to form new stars. Visually intermingled between the spiral arms is a sprinkling of reddish background galaxies.
NGC 1376 resides over 180 million light-years away from Earth in the constellation Eridanus. This galaxy belongs to a class of spirals that are seen nearly face on from our line of sight. Its orientation aids astronomers in studying details and features of the galaxy from a relatively unobscured vantage point. One such feature is represented by stars that vary in brightness over time. In 1990, NGC 1376 was home to a supernova explosion (SN 1990go) that rivaled the brightness of the entire nucleus (as seen from ground-based telescopes) for several weeks.
The story of how this galaxy came to be photographed by Hubble is somewhat unique. During the November 2006 observations of a nearby dwarf galaxy with Hubble's Near Infrared Camera and Multi-Object Spectrometer (NICMOS) detector, careful planning allowed for NGC 1376 to be visible in the field of view of the Advanced Camera for Surveys (ACS) at the same time. Thus, Hubble was able to get two galaxies for the price of one. Although the use of parallel instruments onboard Hubble is not uncommon, capturing two interesting targets is rather rare.
Initial ground-based observations of NGC 1376 and its nearby dwarf companion implied that the two might be interacting with each other, but the Hubble observations demonstrates no obvious signs of interaction. This is not surprising since the dwarf galaxy would have little effect on this giant spiral galaxy. NGC 1376 was imaged with ACS in eight filters ranging from blue to visible to infrared light. Four of the filtered images that show the most colour separation were used in this Hubble composite of NGC 1376.
The full resolution image weighs 1.4 MB, so please be (a little) patient when downloading!
Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)
Acknowledgment: R. Thompson (University of Arizona)

A rare picture of Saturn in natural colours, taken by Hubble

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The NASA/ESA Hubble Space Telescope has provided images of Saturn in many colors, from black-and-white, to orange, to blue, green, and red. But in this picture, image processing specialists have worked to provide a crisp, extremely accurate view of Saturn, which highlights the planet's pastel colors. Bands of subtle colour - yellows, browns, grays - distinguish differences in the clouds over Saturn, the second largest planet in the solar system.
The ring swirling around Saturn consists of chunks of ice and dust. Saturn itself is made of ammonia ice and methane gas. The little dark spot on Saturn is the shadow from Saturn's moon Enceladus.
Credit: Hubble Heritage Team (AURA/STScI/NASA/ESA)

James Webb Space Telescope completes cryogenic mirror test

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On this picture, six James Webb Space Telescope beryllium mirror segments complete a series of cryogenic tests at the X-ray & Cryogenic Facility at NASA's Marshall Space Flight Center in Huntsville, Alabama. The facility at Marshall is the world's largest X-ray telescope test facility and a unique site for cryogenic, clean-room optical testing. During cryogenic testing, the mirrors are subjected to temperatures dipping to -415 degrees Fahrenheit, permitting engineers to measure in extreme detail how the shape of each mirror changes as it cools.
The Webb telescope has a total of 18 mirrors. Each of the 18 mirror segments will be cryogenically tested twice in the Marshall Center's X-ray & Cryogenic Facility to ensure that the mirror will maintain its shape in a space environment - once with bare polished beryllium and then again after a thin coating of gold is applied. The cryogenic test gauges how each mirror changes temperature and shape over a range of operational temperatures in space. This helps predict how well the telescope will image infrared sources.
The mirrors are designed to stay cold to allow scientists to observe the infrared light they reflect using a telescope and instruments optimized to detect this light. Warm objects give off infrared light, or heat. If the Webb telescope mirror is too warm, the faint infrared light from distant galaxies may be lost in the infrared glow of the mirror itself. Thus, the Webb telescope's mirrors need to operate in a deep cold or cryogenic state, at around -379 degree Fahrenheit.
Northrop Grumman is the prime contractor for the Webb telescope, leading a design and development team under contract to NASA's Goddard Space Flight Center in Greenbelt, Maryland.
The James Webb Space Telescope is NASA's next-generation premier space observatory, exploring deep space phenomena from the formation of distant galaxies to the behavior and interrelationships of nearby planets and stars. The Webb telescope will give scientists clues about the formation of the universe and the evolution of our own solar system, from the first light after the Big Bang to the formation of star systems capable of supporting life on planets like Earth.
The full resolution image weighs 9.4 MB, so please be patient when downloading!
Credit: NASA/MSFC/David Higginbotham/Emmett Given

The 8.2-m Very Large Telescope main mirrors: near-perfect optics

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This photo shows the fourth 8.2-meter VLT Zerodur mirror during the final phase of polishing at French company REOSC. On December 14, 1999, REOSC, the Optical Department of the SAGEM Group, finished the polishing of the fourth 8.2-meter main mirror for the Very Large Telescope (VLT) of the European Southern Observatory. The mirror was delivered to ESO at a ceremony at the REOSC factory in Saint Pierre du Perray, just south of Paris. The precision of the form of the mirror that was achieved during the polishing process is 8.5 nanometer (1 nanometer = 1 millionth of a millimetre) over the optical surface. This exceptional value corresponds to an optical resolution (theoretical image sharpness) of 0.03 arcseconds in the visible spectrum. This corresponds to distinguishing two objects separated by only 15 cm at a distance of 1000 km and it allows to detect astronomical objects that are 10,000 million times fainter than what can be perceived with the unaided eye. The other three VLT primary mirrors were polished to a comparable precision. REOSC was also in charge of the polishing process of the twin 8-meter Gemini North and South primary mirrors and of the 3.6-meter primary mirror for the Canada-France-Hawaii Telescope (CFHT) on Mauna Kea, Hawaii.
Credit: ESO

Large Binocular Telescope Interferometer sees First Llight

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The Large Binocular Telescope Interferometer saw "first light" in the beginning of this month. The Large Binocular Telescope Interferometer has taken its first images of the star Beta Peg in the constellation Pictor - an encouraging start for an instrument designed to probe the cosmic neighborhoods where Earth-like planets could exist.
Eight years in development, the NASA-funded instrument combines beams of light from twin 8.4-meter (28-foot) mirrors mounted atop the Large Binocular Telescope on Mount Graham, Arizona, USA. Together, the two mirrors form the largest single-mount telescope in the world.
With this high-resolution imaging capability, astronomers hope to probe nearby solar systems - specifically, the areas in these systems where Earth-like planets with liquid water could exist. Though the Large Binocular Telescope Interferometer won't be able to detect Earth-size planets, it will be able to see dust disks that are indicative of planet formation, in addition to detecting large, Jupiter-size planets farther out from the star. These findings will help future, space-based exoplanet missions know where to search for Earth-like planets in our own galactic neighborhood.
With its ability to probe this "habitable zone" of other solar systems, the Large Binocular Telescope Interferometer will also complement the capabilities of other NASA missions - the Keck Interferometer, which can find dust very close to stars; and the Spitzer Space Telescope, which is adept at observing planet-forming dust that is much more distant.
With a major upgrade of the Large Binocular Telescope's adaptive optics system scheduled for next year, the interferometer will undergo testing and commissioning for the majority of 2011, and during that time, scientific observations will begin. The interferometer will be able to image exoplanets, but also extragalactic objects, nebulae and galaxies.
The Large Binocular Telescope Interferometer is funded by NASA and managed by Ben Parvin at NASA's Jet Propulsion Laboratory, Pasadena, California, as part of NASA's Exoplanet Exploration Program. The instrument and product development are provided by the University of Arizona, Tucson.
Credit: Large Binocular Telescope Observatory

The Great Barrier Reef, the largest single living structure on Earth

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This Envisat image features the southern part of the Great Barrier Reef off Australia's Queensland coast. It is the world's most protected marine area, one of its natural wonders and a World Heritage site. Spanning more than 2,000 km and covering an area of some 350,000 sq km, it is the largest living structure on Earth and the only one visible from space. This image was acquired by Envisat's Medium Resolution Imaging Spectrometer (MERIS) on 8 November 2010 at a resolution of 300 m.
Credit: ESA

Bacolor Crater as viewed by NASA's Mars Odyssey orbiter

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Bacolor Crater is a magnificent impact feature about 20 kilometers (12 miles) wide. The lines on the ejecta blanket surrounding the crater rim come from a surge of superheated gas and debris flying outward in the wake of the meteorite impact that made the crater.
This view combines images taken during the period from September 2002 to October 2005 by the Thermal Emission Imaging System instrument on NASA's Mars Odyssey orbiter. It is part of a special set of images marking the occasion of Odyssey becoming the longest-working Mars spacecraft in history. The pictured location on Mars is 33 degrees north latitude, 118.6 degrees east longitude.
NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Science Mission Directorate, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.
Credit: NASA/JPL-Caltech/ASU

ESO’s Very Large Telescope ready for a long observing night

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As soon as the Sun sets over the Chilean Atacama Desert, ESO's Very Large Telescope (VLT) begins catching light from the far reaches of the Universe. The VLT has four 8.2-meter Unit Telescopes such as the one shown in the photograph. Many of the photons - particles of light - that are collected have travelled through space for billions of years before reaching the telescope's primary mirror. The giant mirror acts like a high-tech "light bucket", gathering as many photons as possible and sending them to sensitive detectors. Careful analysis of the data from these instruments allows astronomers to unravel the mysteries of the cosmos.
The telescopes have a variety of instruments, which allow them to observe in a range of wavelengths from near-ultraviolet to mid-infrared. The VLT also boasts advanced adaptive optics systems, which counteract the blurring effects of the Earth's atmosphere, producing images so sharp that they could almost have been taken in space.
Credit: ESO/José Francisco Salgado

The first Saturn V rocket on launch pad 39A

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Early morning photo on November 9, 1967 of launch pad 39A, Kennedy Space Center, showing Saturn V (SA-501) for the Apollo 4 mission (Spacecraft 017) prior to launch later that day. This was the first test launch of the Saturn V rocket. On May 25, 1961, U.S. president John Kennedy announced the goal of landing Americans on the Moon by the end of the decade. Kennedy's ambitious speech triggered a nearly unprecedented peacetime technological mobilization and one result was the Saturn V moon rocket. Its development directed by rocket pioneer Wernher Von Braun, the three stage Saturn V stood over 36 stories tall. It had a cluster of five first stage engines fueled by liquid oxygen and kerosene which together were capable of producing 7.5 million pounds of thrust. Giant Saturn V rockets ultimately hurled nine Apollo missions to the Moon and back again with six landing on the lunar surface. The first landing, by Apollo 11, occurred on July 20, 1969 achieving Kennedy's goal. Boeing, McDonnell Douglas and North American Aviation collaborated to develop and produce the mammoth 363-foot Saturn V rocket. All 15 S-1Cs were built between 1965 and 1975. Twelve were used on the Apollo missions, and the 13th, in 1973, placed Skylab in Earth orbit. The remaining rockets were placed on display.
Credit: Boeing
Image restoration: Jean-Baptiste Faure

The Hubble's view of the dazzling Planetary Nebula NGC 6572

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The NASA/ESA Hubble Space Telescope has turned its eagle eye to the planetary nebula NGC 6572, a very bright example of these strange but beautiful objects. Planetary nebulae are created during the late stages of the evolution of certain stars that eject gas into space and emit intense ultraviolet radiation that makes the material glow. This picture of NGC 6572 shows the intricate shapes that can develop as stars exhale their last breaths. Hubble has even imaged the central white dwarf star, the origin of the dazzling nebula, but now a faint, but hot, vestige of its former glory.
NGC 6572 only began to shed its gases a few thousand years ago, so it is a fairly young planetary nebula. As a result the material is still quite concentrated, which explains why it is abnormally bright. The envelope of gas is currently racing out into space at a speed of around 15 kilometres every second and as it becomes more diffuse, it will dim.
NGC 6572 was discovered in 1825 by the German astronomer Friedrich Georg Wilhelm von Struve, who came from a family of distinguished stargazers. The name planetary nebula is left over from the time when the telescopes of early astronomers were not good enough to reveal the true nature of these objects. To many, the discs looked like the outer planets Uranus and Neptune. The application of spectral analysis, later in the 19th century, first revealed that they were glowing gas clouds.
NGC 6572 is magnitude 8.1, easily bright enough to make it an appealing target for amateur astronomers with telescopes. It is located within the large constellation of Ophiuchus (the Serpent Bearer) and at low magnification it will appear to be just a coloured star, but higher magnification will reveal its shape. Some observers report that NGC 6572 looks blue, while others state that it is green. Colour as seen through the eyepiece is often a matter of interpretation, so you may make your own decision!
This picture was created from images taken with Hubble’s Wide Field Camera 2. Images through a blue filter that isolates the glow from hydrogen gas (Hβ, F487N, coloured dark blue), a green filter that isolates emission from ionised oxygen (F502N, coloured blue), a yellow broadband filter (F555W, coloured green) and a red filter that passes emission from hydrogen (Hα, F656N) have been combined. The exposure times were 360 s, 240 s, 100 s and 180 s, respectively and the field of view is just 29 arcseconds across.
Credit: ESA/Hubble and NASA

Hubble and Chandra picture celestial bubble SNR 0509 in the LMC

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This delicate shell, photographed by the NASA/ESA Hubble Space Telescope, appears to float serenely in the depths of space, but this apparent calm hides an inner turmoil. The gaseous envelope formed as the expanding blast wave and ejected material from a supernova tore through the nearby interstellar medium. Called SNR B0509-67.5 (or SNR 0509 for short), the bubble is the visible remnant of a powerful stellar explosion in the Large Magellanic Cloud (LMC), a small galaxy about 160 000 light-years from Earth. Ripples in the shell’s surface may be caused either by subtle variations in the density of the ambient interstellar gas, or possibly be driven from the interior by fragments from the initial explosion. The bubble-shaped shroud of gas is 23 light-years across and is expanding at more than 18 million km/h.
Hubble’s Advanced Camera for Surveys observed the supernova remnant on 28 October 2006 with a filter that isolates light from the glowing hydrogen seen in the expanding shell. These observations were then combined with visible-light images of the surrounding star field that were imaged with Hubble’s Wide Field Camera 3 on 4 November 2010, and archival X-ray observations taken by NASA’s Chandra X-ray Observatory.
Credit: NASA, ESA, the Hubble Heritage Team (STScI/AURA), and NASA/CXC/SAO/J. Hughes

Hubble's sharpest image of the Orion Nebula!

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This dramatic image offers a peek inside a cavern of roiling dust and gas where thousands of stars are forming. The image, taken by the Advanced Camera for Surveys (ACS) aboard NASA's Hubble Space Telescope, represents the sharpest view ever taken of this region, called the Orion Nebula. More than 3,000 stars of various sizes appear in this image. Some of them have never been seen in visible light. These stars reside in a dramatic dust-and-gas landscape of plateaus, mountains, and valleys that are reminiscent of the Grand Canyon. The Orion Nebula is a picture book of star formation, from the massive, young stars that are shaping the nebula to the pillars of dense gas that may be the homes of budding stars. The bright central region is the home of the four heftiest stars in the nebula. The stars are called the Trapezium because they are arranged in a trapezoid pattern. Ultraviolet light unleashed by these stars is carving a cavity in the nebula and disrupting the growth of hundreds of smaller stars. Located near the Trapezium stars are stars still young enough to have disks of material encircling them. These disks are called protoplanetary disks or "proplyds" and are too small to see clearly in this image. The disks are the building blocks of solar systems. The bright glow at upper left is from M43, a small region being shaped by a massive, young star's ultraviolet light. Astronomers call the region a miniature Orion Nebula because only one star is sculpting the landscape. The Orion Nebula has four such stars. Next to M43 are dense, dark pillars of dust and gas that point toward the Trapezium. These pillars are resisting erosion from the Trapezium's intense ultraviolet light. The glowing region on the right reveals arcs and bubbles formed when stellar winds - streams of charged particles ejected from the Trapezium stars - collide with material. The faint red stars near the bottom are the myriad brown dwarfs that Hubble spied for the first time in the nebula in visible light. Sometimes called "failed stars," brown dwarfs are cool objects that are too small to be ordinary stars because they cannot sustain nuclear fusion in their cores the way our Sun does. The dark red column, below, left, shows an illuminated edge of the cavity wall. The Orion Nebula is 1,500 light-years away, the nearest star-forming region to Earth. Astronomers used 520 Hubble images, taken in five colors, to make this picture. They also added ground-based photos to fill out the nebula. The ACS mosaic covers approximately the apparent angular size of the full moon.
Credit: NASA, ESA, M. Robberto (Space Telescope Science Institute/ESA) and the Hubble Space Telescope Orion Treasury Project Team
Post-processing: Jean-Baptiste Faure

Hubble captures the core of M13, the Hercules Globular Cluster

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This image, taken by the Advanced Camera for Surveys on the Hubble Space Telescope, shows the core of the great globular cluster Messier 13 and provides an extraordinarily clear view of the hundreds of thousands of stars in the cluster, one of the brightest and best known in the sky. Just 25 000 light-years away and about 145 light-years in diameter, Messier 13 has drawn the eye since its discovery by Edmund Halley, the noted British astronomer, in 1714. The cluster lies in the constellation of Hercules and is so bright that under the right conditions it is even visible to the unaided eye. As Halley wrote: "This is but a little Patch, but it shews it self to the naked Eye, when the Sky is serene and the Moon absent." Messier 13 was the target of a symbolic Arecibo radio telescope message that was sent in 1974, communicating humanity's existence to possible extraterrestrial intelligences. However, more recent studies suggest that planets are very rare in the dense environments of globular clusters.
Messier 13 has also appeared in literature. In his 1959 novel, The Sirens of Titan, Kurt Vonnegut wrote "Every passing hour brings the Solar System forty-three thousand miles closer to Globular Cluster M13 in Hercules - and still there are some misfits who insist that there is no such thing as progress." The step from Halley's early telescopic view to this Hubble image indicates some measure of the progress in astronomy in the last three hundred years. This picture was created from images taken with the Wide Field Channel of the Advanced Camera for Surveys on the Hubble Space Telescope. Data through a blue filter (F435W) are coloured blue, data through a red filter (F625W) are coloured green and near-infrared data (through the F814W filter) are coloured red. The exposure times are 1480 s, 380 s and 567 s respectively and the field of view is about 2.5 arcminutes across.
The full resolution image weighs 5.7 MB, so please be patient when downloading!
Credit: ESA/Hubble and NASA

Hubble pictures young stars born inside M16, the Eagle Nebula

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The NASA/ESA Hubble Space Telescope has once more turned its attention towards the magnificent Eagle Nebula (Messier 16). This picture shows the northwestern part of the region, well away from the centre, and features some very bright young stars that formed from the same cloud of material. These energetic toddlers are part of an open cluster and emit ultraviolet radiation that causes the surrounding nebula to glow.
The star cluster is very bright and was discovered in the mid-eighteenth century. The nebula, however, is much more elusive and it took almost a further two decades for it to be first noted by Charles Messier in 1764. Although it is commonly known as the Eagle Nebula, its official designation is Messier 16 and the cluster is also named NGC 6611. One spectacular area of the nebula (outside the field of view) has been nicknamed "The Pillars of Creation" ever since the Hubble Space Telescope captured an iconic image of dramatic pillars of star-forming gas and dust.
The cluster and nebula are fascinating targets for small and medium-sized telescopes, particularly from a dark site free from light pollution. Messier 16 can be found within the constellation of Serpens Cauda (the Tail of the Serpent), which is sandwiched between Aquila, Sagittarius, and Ophiuchus in the heart of one of the brightest parts of the Milky Way. Small telescopes with low power are useful for observing large, but faint, swathes of the nebula, whereas 30 cm telescopes and larger may reveal the dark pillars under good conditions. But a space telescope in orbit around the Earth, like Hubble - which boasts a 2.4-metre diameter mirror and state-of-the-art instruments - is required for an image as spectacular as this one.
This picture was created from images taken with the Wide Field Channel of Hubble's Advanced Camera for Surveys. Images through a near-infrared filter (F775W) are coloured red and images through a blue filter (F475W) are blue. The exposures times were one hour and 54 minutes respectively and the field of view is about 3.3 arcminutes across.
Credit: ESA/Hubble and NASA

Mars Express: wind and water have shaped Schiaparelli on Mars!

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This ultra high resolution image of Schiaparelli on Mars shows just a small part of the crater's north-western rim cutting diagonally across the image (top left to bottom right) and a smaller 42-kilometer diameter crater embedded in its rim. Schiaparelli is a large impact basin about 460 kilometres across, located in the eastern Terra Meridiani region on Mars's equator. The image is centred on the equator of Mars, at a longitude of about 14°E. The DLR-operated High-Resolution Stereo Camera (HRSC) on ESA's Mars Express spacecraft acquired the image on 15 July 2010. The spacecraft was completing orbit 8363 of Mars and the ground resolution of the image is about 19 metres per pixel. All around is evidence of water in the past and the strong Martian winds that blow periodically.
The scene shows a small part of the north-western area of the Schiaparelli basin with the crater rim, the crater interior and parts of the surrounding highlands. Evidence for water can be seen in the form of dark sediments that appear on the floor of Schiaparelli, resembling those deposited by evaporated lakes on Earth.
The interior of Schiaparelli has been modified by multiple geological processes, including the fall of ejecta blasted upwards by the initial impact, flows of lava that created the smooth plains and deposition of watery sediments.
The High-Resolution Stereo Camera, HRSC, on the European Space Agency's Mars Express mission is led by the Principal Investigator (PI) Prof. Dr Gerhard Neukum, who was also responsible for the technical design of the camera. The science team of the experiment consists of 45 co-investigators from 32 institutions and 10 nations. The camera was developed at the German Aerospace Center, DLR, under the leadership of the PI and it was built in cooperation with industrial partners EADS Astrium, Lewicki Microelectronic GmbH and Jena-Optronik GmbH. The instrument on Mars Express is operated by the DLR Institute of Planetary Research, through ESA/ESOC. The systematic processing of the HRSC image data is carried out at DLR. The scenes shown here were processed by the PI-group at the Institute for Geosciences of the Freie Universitat Berlin in cooperation with the DLR Institute of Planetary Research, Berlin.
Credit: ESA/DLR/FU Berlin (G. Neukum)

NASA's long-lasting Mars Odyssey orbiter shoots Udzha Crater

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Although it is 45 kilometers (28 miles) wide, countless layers of ice and dust have all but buried Udzha Crater. Udzha lies near the edge of the northern polar cap, and only the topmost edges of its crater rim rise above the polar deposits to hint at its circular shape.
The image was taken by the Thermal Emission Imaging System instrument on NASA's Mars Odyssey orbiter and posted in a special December 2010 set marking the occasion of Odyssey becoming the longest-working Mars spacecraft in history. The pictured location on Mars is 81.8 degrees north latitude, 77.2 degrees east longitude.
NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Science Mission Directorate, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.
Credit: NASA/JPL-Caltech/ASU

A New Era - SpaceX launches Falcon 9 on demonstration flight!

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SpaceX’s Falcon 9 rocket and Dragon spacecraft lift off from Launch Complex-40 at Cape Canaveral Air Force Station, Fla., at 10:43 a.m. EST, Wednesday, Dec. 8, 2010. In orbit, the Dragon capsule went through several maneuvers before it re-entered the atmosphere and splashed down in the Pacific Ocean about 500 miles west of the coast of Mexico. This is first demonstration flight for NASA's Commercial Orbital Transportation Services (COTS) program, which will provide cargo flights to the International Space Station in the future.
Credit: NASA/Tony Gray and Kevin O'Connell

A new deep image of the region of beautiful M81 and Arp's Loop

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One of the brightest galaxies in planet Earth's sky and similar in size to the Milky Way, big, beautiful spiral M81 lies 11.8 million light-years away in the northern constellation Ursa Major. This deep image of the region reveals details in the bright yellow core, but at the same time follows fainter features along the galaxy's gorgeous blue spiral arms and sweeping dust lanes. It also follows the expansive, arcing feature, known as Arp's loop, that seems to rise from the galaxy's disk at the right. Studied in the 1960s, Arp's loop has been thought to be a tidal tail, material pulled out of M81 by gravitational interaction with its large neighboring galaxy M82. But a recent investigation demonstrates that much of Arp's loop likely lies within our own galaxy. The loop's colors in visible and infrared light match the colors of pervasive clouds of dust, relatively unexplored galactic cirrus only a few hundred light-years above the plane of the Milky Way. Along with the Milky Way's stars, the dust clouds lie in the foreground of this remarkable view. M81's dwarf companion galaxy, Holmberg IX, can be seen just above and left of the large spiral. On the sky, this image spans about 0.5 degrees, about the size of the Full Moon.
This image is taken from the Astronomy Picture of the Day (APOD) of December 9, 2010.
Credit & Copyright: R Jay GaBany - Collaboration: A. Sollima (IAC),
A. Gil de Paz (U. Complutense Madrid) D. Martínez-Delgado (IAC, MPIA), J.J. Gallego-Laborda (Fosca Nit Obs.), T. Hallas (Hallas Obs.)

Pluto's tiny atmosphere and pure methane on its icy surface

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Artist's impression of how the surface of Pluto might look, according to one of the two models that a team of astronomers has developed to account for the observed properties of Pluto's atmosphere, as studied with CRIRES. The image shows patches of pure methane on the surface and Charon is visible near the left border of the image. At the distance of Pluto, the sun appears about 1,000 times fainter than on Earth.
Credit: ESO/L. Calçada

A visualization of the sun and Charon from the surface of Pluto

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A visualization of what the sun might look like from the surface of Pluto. Charon and the sun are in conjunction.
Credit: Jeff Bryant

Pluto as seen by the Hubble Space Telescope!

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This is the best shot of Pluto to date, taken by the Hubble Space Telescope. The images from NASA's Hubble Space Telescope show an icy, mottled, dark molasses-colored world undergoing seasonal surface color and brightness changes. Hubble's view isn't sharp enough to see craters or mountains, if they exist on the surface, but Hubble reveals a complex-looking and variegated world with white, dark-orange, and charcoal-black terrain. The overall color is believed to be a result of ultraviolet radiation from the distant Sun breaking up methane that is present on Pluto's surface, leaving behind a dark, molasses-colored, carbon-rich residue. Astronomers were very surprised to see that Pluto's brightness has changed - the northern pole is brighter and the southern hemisphere is darker and redder. Summer is approaching Pluto's north pole, and this may cause surface ices to melt and refreeze in the colder shadowed portion of the planet. The Hubble pictures underscore that Pluto is not simply a ball of ice and rock but a dynamic world that undergoes dramatic atmospheric changes.
Credit: NASA, ESA and M. Buie (Southwest Research Institute)
Image enhancement: Jean-Baptiste Faure

Space Shuttle main engine: 6,000 degrees F inside, cool outside!

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A space shuttle main engine stands alone. Technicians have rotating devices to position the engines for processing. A space shuttle main engine burns at 6,000 degrees F, but the outside of the nozzle remains cool to the touch. Prior to launch, sometimes it even frosts over.
Credit: NASA/Jack Pfaller

A brilliant portrait of Stephan's Quintet by Hubble!

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A clash among members of a famous galaxy quintet reveals an assortment of stars across a wide colour range, from young, blue stars to aging, red stars. This portrait of Stephan's Quintet, also known as the Hickson Compact Group 92, was taken by the new Wide Field Camera 3 (WFC3) aboard the NASA/ESA Hubble Space Telescope. Stephan's Quintet, as the name implies, is a group of five galaxies. The name, however, is a bit of a misnomer. Studies have shown that group member NGC 7320, at upper left, is actually a foreground galaxy that is about seven times closer to Earth than the rest of the group. Three of the galaxies have distorted shapes, elongated spiral arms, and long, gaseous tidal tails containing myriad star clusters, proof of their close encounters. These interactions have sparked a frenzy of star birth in the central pair of galaxies. This drama is being played out against a rich backdrop of faraway galaxies. The image, taken in visible and near-infrared light, showcases WFC3's broad wavelength range. The colours trace the ages of the stellar populations, showing that star birth occurred at different epochs, stretching over hundreds of millions of years. The camera's infrared vision also peers through curtains of dust to see groupings of stars that cannot be seen in visible light. NGC 7319, at top right, is a barred spiral with distinct spiral arms that follow nearly 180 degrees back to the bar. The blue specks in the spiral arm at the top of NGC 7319 and the red dots just above and to the right of the core are clusters of many thousands of stars. Most of the Quintet is too far away even for Hubble to resolve individual stars. Continuing clockwise, the next galaxy appears to have two cores, but it is actually two galaxies, NGC 7318A and NGC 7318B. Encircling the galaxies are young, bright blue star clusters and pinkish clouds of glowing hydrogen where infant stars are being born. These stars are less than 10 million years old and have not yet blown away their natal cloud. Far away from the galaxies, at right, is a patch of intergalactic space where many star clusters are forming. NGC 7317, at bottom left, is a normal-looking elliptical galaxy that is less affected by the interactions. Sharply contrasting with these galaxies is the dwarf galaxy NGC 7320 at upper left. Bursts of star formation are occurring in the galaxy's disc, as seen by the blue and pink dots. In this galaxy, Hubble can resolve individual stars, evidence that NGC 7320 is closer to Earth. NGC 7320 is 40 million light-years from Earth. The other members of the Quintet reside about 300 million light-years away in the constellation Pegasus.
These more distant members are markedly redder than the foreground galaxy, suggesting that older stars reside in their cores. The stars' light also may be further reddened by dust stirred up in the encounters. Spied by Edouard M. Stephan in 1877, Stephan's Quintet is the first compact group ever discovered.
WFC3 observed the Quintet in July and August 2009. The composite image was made by using filters that isolate light from the blue, green and infrared portions of the spectrum, as well as emission from ionised hydrogen.
These Hubble observations are part of the Hubble Servicing Mission 4 Early Release Observations. NASA astronauts installed the WFC3 camera during a servicing mission in May to upgrade and repair the 19-year-old Hubble telescope.
The full resolution image weighs 10.6 MB, so please be patient when downloading!
Credit: NASA, ESA and the Hubble SM4 ERO Team

This is Pleiades, NASA's largest, most powerful supercomputer!

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NASA's largest, most powerful supercomputer, Pleiades, features a 56,832-processor Silicon Graphics International Altix ICE system. Pleiades' storage system, with an approximately 1.4 petabyte capacity, and the hyperwall-2 visualization system, featuring 128 screens, which measure 23-feet by 10-feet is located at the NASA Advanced Supercomputing (NAS) facility at NASA's Ames Research Center, Moffett Field, California.
Credit: NASA

STS-129 Space Shuttle Atlantis on Pad 39A

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The space shuttle Atlantis is seen on launch pad 39A of the NASA Kennedy Space Center (KSC) shortly after the rotating service structure was rolled back, Sunday, November 15, 2009 in Cape Canaveral, Florida.
Credit: NASA/Bill Ingalls

A stunning image of Enceladus by NASA's Cassini spacecraft

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Just after coming within 25 kilometers (15.6 miles) of the surface of Enceladus, NASA's Cassini captured this stunning mosaic as the spacecraft sped away from this geologically active moon of Saturn.
Craters and cratered terrains are rare in this view of the southern region of the moon's Saturn-facing hemisphere. Instead, the surface is replete with fractures, folds, and ridges--all hallmarks of remarkable tectonic activity for a relatively small world. In this enhanced-color view, regions that appear blue-green are thought to be coated with larger grains than those that appear white or gray.
Portions of the tiger stripe fractures, or sulci, are visible along the terminator at lower right, surrounded by a circumpolar belt of mountains. The icy moon's famed jets emanate from at least eight distinct source regions, which lie on or near the tiger stripes. However, in this view, the most prominent feature is Labtayt Sulci, the approximately one-kilometer (0.6 miles) deep northward-trending chasm located just above the center of the mosaic.
Near the top, the conspicuous ridges are Ebony and Cufa Dorsae. This false-color mosaic was created from 28 images obtained at seven footprints, or pointing positions, by Cassini's narrow-angle camera. At each footprint, four images using filters sensitive to ultraviolet, visible and infrared light (spanning wavelengths from 338 to 930 nanometers) were combined to create the individual frames. The mosaic is an orthographic projection centered at 64.49 degrees south latitude, 283.87 west longitude, and it has an image scale of 196 kilometers (122.5 miles) per pixel. The original images ranged in resolution from 180 meters (594 feet) to 288 meters (950 feet) per pixel and were acquired at distances ranging from 30,000 to 48,000 kilometers (18,750 to 30,000 miles) as the spacecraft receded from Enceladus. The view was acquired at a Sun-Enceladus-spacecraft, or phase, angle of 73 degrees.
Credit: NASA/JPL/Space Science Institute

The first color view of Titan's surface taken by the Huygens probe

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This image was captured by the European Space Agency's Huygens probe during its successful descent to land on Titan. This is the colored view, following processing to add reflection spectra data, and gives a better indication of the actual color of the surface.
Initially thought to be rocks or ice blocks, they are more pebble-sized. The two rock-like objects just below the middle of the image are about 15 centimeters (about 6 inches) (left) and 4 centimeters (about 1.5 inches) (center) across respectively, at a distance of about 85 centimeters (about 33 inches) from Huygens. The surface is darker than originally expected, consisting of a mixture of water and hydrocarbon ice. There is also evidence of erosion at the base of these objects, indicating possible fluvial activity.
The image was taken with the Descent Imager/Spectral Radiometer, one of two NASA instruments on the probe.
Credit: NASA/JPL/ESA/University of Arizona

Sunlight reflected off a lake on Saturn's moon Titan!

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This image shows the first flash of sunlight reflected off a lake on Saturn's moon Titan. The glint off a mirror-like surface is known as a specular reflection. This kind of glint was detected by the visual and infrared mapping spectrometer (VIMS) on NASA's Cassini spacecraft on July 8, 2009. It confirmed the presence of liquid in the moon's northern hemisphere, where lakes are more numerous and larger than those in the southern hemisphere. Scientists using VIMS had confirmed the presence of liquid in Ontario Lacus, the largest lake in the southern hemisphere, in 2008. The northern hemisphere was shrouded in darkness for nearly 15 years, but the sun began to illuminate the area again as it approached its spring equinox in August 2009. VIMS was able to detect the glint as the viewing geometry changed. Titan's hazy atmosphere also scatters and absorbs many wavelengths of light, including most of the visible light spectrum. But the VIMS instrument enabled scientists to look for the glint in infrared wavelengths that were able to penetrate through the moon's atmosphere. This image was created using wavelengths of light in the 5 micron range. By comparing the new image to radar and near-infrared light images acquired from 2006 to 2008, Cassini scientists were able to correlate the reflection to the southern shoreline of a Titan lake called Kraken Mare. The sprawling Kraken Mare covers about 400,000 square kilometers (150,000 square miles). The reflection appeared to come from a part of the lake around 71 degrees north latitude and 337 degrees west latitude. It was taken on Cassini's 59th flyby of Titan on July 8, 2009, at a distance of about 200,000 kilometers (120,000 miles). The image resolution was about 100 kilometers (60 miles) per pixel. Image processing was done at the German Aerospace Center in Berlin and the University of Arizona in Tucson.
Credit: NASA/JPL/University of Arizona/DLR
Image enhancement: Jean-Baptiste Faure

Saturn's moon Tethys with Odysseus crater slips behind Titan

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Saturn's moon Tethys with its prominent Odysseus crater silently slips behind Saturn's largest moon Titan and then emerges on the other side.
Tethys is not actually enshrouded in Titan's atmosphere. Tethys (1,062 kilometers, or 660 miles across) is more than twice as far from Cassini than Titan (5,150 kilometers, or 3,200 miles across) in this sequence. Tethys is 2.2 million kilometers (1.4 million miles) from Cassini. Titan is about 1 million kilometers (621,000 miles) away.
These two color views were captured about 18 minutes apart, with the view on the right taking place first. These images are part of a mutual event sequence in which one moon passes close to or in front of another as seen from the spacecraft. Such observations help scientists refine their understanding of the orbits of Saturn's moons.
Images taken using red, green and blue spectral filters were combined to create this natural color view. The images were obtained with the Cassini spacecraft narrow-angle camera on Nov. 26, 2009. Image scale is 6 kilometers (4 miles) per pixel on Titan and 13 kilometers (8 miles) per pixel on Tethys.
Credit: NASA/JPL/Space Science Institute

Does this Martian crater reveal the existence of Liquid Water?

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This image shows a fresh, approximately 7.5 kilometer diameter crater that resides in a larger crater in the Southern hemisphere of Mars.
The crater shown here has very few craters superposed on it, which attests to its youth. It also has very steep slopes and a sharp rim; more evidence of its young age. Young, fresh craters are of interest on Mars because they help place constraints on the rate at which new impact craters and other young features have formed in recent times.
This fresh crater is particularly interesting because it contains gullies. Gullies are slope features that are proposed to require some amount of liquid water to form. The gullies must have formed after the crater did, which means that if liquid water was involved in the formation of these gullies, then it existed on the surface of Mars more recently. The existence of recent liquid water is especially important in terms of the search for life on Mars and its future exploration.
Several of the gullies show features such as terraces, discontinuous channels, and abandoned channels; all of which imply that more than one flow event occurred. It is unknown whether or not such multiple flows would have been closely spaced in time.
Terraces are thought to indicate past flow levels. Discontinuous channels may represent some subsurface flow in addition to surface flow, or they may be channels that were once continuous that have since been filled in with wind-blown sediment and dust. The latter is the most likely in the subimage. For example, see the discontinuous channel near the center; it appears to have sediment infilling it. Abandoned channels are paths that fluid flowed through in the past before another flow took a different direction.
Credit: NASA/JPL-Caltech/University of Arizona

Cassini returns images of bright jets at Saturn's moon Enceladus

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NASA's Cassini spacecraft successfully dipped near the surface of Saturn's moon Enceladus on Nov. 30. Though Cassini's closest approach took it to within about 48 kilometers (30 miles) of the moon's northern hemisphere, the spacecraft also captured shadowy images of the tortured south polar terrain and the brilliant jets that spray out from it.
Many of the raw images feature darkened terrain because winter has descended upon the southern hemisphere of Enceladus. But sunlight behind the moon backlights the jets of water vapor and icy particles. In some images, the jets line up in rows, forming curtains of spray.

The Enceladus flyby was the 12th of Cassini's mission, with the spacecraft swooping down around 61 degrees north latitude. This encounter and its twin three weeks later at the same altitude and latitude, are the closest Cassini will come to the northern hemisphere surface of Enceladus during the extended Solstice mission. (Cassini's closest-ever approach to Enceladus occurred in October 2008, when the spacecraft dipped to an altitude of 25 kilometers, or 16 miles.)
Among the observations Cassini made during this Enceladus flyby, the radio science subsystem collected gravity measurements to understand the moon's interior structure, and the fields and particles instruments sampled the charged particle environment around the moon.
About two days before the Enceladus flyby, Cassini also passed the sponge-like moon Hyperion (above), beaming back intriguing images of the craters on its surface. The flyby, at 72,000 kilometers (45,000 miles) in altitude, was one of the closest approaches to Hyperion that Cassini has made.
Scientists are still working to analyze the data and images collected during the flybys.
Credit: NASA/JPL/SSI

Mars Reconnaissance Orbiter image showing an old ridge on Mars

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This Mars Reconnaissance Orbiter image shows a ridge in Mars' Terra Meridiani that is most likely a former streambed, now exposed in inverted relief. The stream that formed this ridge must have been ancient as the ridge is buried by brighter rocks, which are themselves very old, having been thickly deposited and then heavily eroded.
The Mars Exploration Rover Opportunity landed in the same region of Mars, and the rocks it has examined are likely part of a sequence similar to that exposed here. The rocks exposed at the Opportunity landing site are mostly wind-deposited sandstone, but show evidence of past water, reaching the surface at times. Opportunity has access to only a few meters of a stack of sediments that is hundreds of meters thick.
Credit: NASA/JPL-Caltech/University of Arizona

ATLAST: beyond Hubble and the James Webb Space Telescope!

The Advanced Technology Large Aperture Space Telescope (ATLAST) is a NASA strategic mission concept study for the next generation of Ultraviolet-Visible-Infrared (UVOIR) space observatory. ATLAST will have a primary mirror diameter in the 8-meter to 16-meter range that will allow scientists to perform some of the most challenging observations to answer some of the most compelling astrophysical questions.
The greatest leaps in our understanding of the universe typically follow the introduction of radically new observational capabilities that bring previously unobserved phenomena into view. Some, such as the unambiguous detection of life on an Earth-like planet orbiting another star, will be profound yet conceivable. Others are entirely beyond our imagination. All forever change our view of our place in the universe.

ATLAST is envisioned as a flagship mission of the 2025 - 2035 period, designed to address one of the most compelling questions of our time. Is there life elsewhere in our Galaxy? It will accomplish this by detecting "biosignatures" (such as molecular oxygen, ozone, water, and methane) in the spectra of terrestrial exoplanets.
But ATLAST is more than just a "life-finder". ATLAST will have the performance required to reveal the underlying physics that drives star formation and to trace the complex interactions between dark matter, galaxies, and the intergalactic medium. Because of the large leap in observing capabilities that ATLAST will provide, we cannot fully anticipate the diversity or direction of the investigations that will dominate its use - just as the creators of HST did not foresee its pioneering roles in characterizing the atmospheres of Jupiter-mass exoplanets or measuring the acceleration of cosmic expansion using distant supernovae.
ATLAST will have the versatility to far outlast the scientific vision of current-day astronomers.
NASA has identified two different telescope architectures, but with similar optical designs, that span the range in viable technologies. The architectures are a telescope with a monolithic primary mirror and two variations of a telescope with a large segmented primary mirror.

Artist's concepts of two ATLAST designs. Top: 8-meter monolithic mirror telescope (credit: MSFC Advanced Concepts Office). Left: 16-meter segmented mirror telescope.
The concepts invoke heritage from HST and JWST design, but also take significant departures from these designs to minimize complexity, mass, or both. ATLAST will have an angular resolution that is 5 - 10 times better than the James Webb Space Telescope (JWST) and a sensitivity limit that is up to 2000 times better than the Hubble Space Telescope (HST).
Two of the concepts, the 8-meter monolithic mirror telescope and the 16.8-meter segmented mirror telescope, span the range of UVOIR observatories that are enabled by NASA's proposed Ares V launch vehicle, which is part of Project Constellation. The 8-meter ATLAST offers the inherent advantages of a monolithic aperture telescope in terms of high-contrast imaging and superb wavefront control. The 16-meter ATLAST represents a pathway to truly large apertures in space and uses the largest extrapolation of a JWST-like chord-fold primary mirror packaging. However, the ATLAST mission is not solely dependent on Ares V. The third concept, a 9.2-meter segmented telescope, is compatible with an Evolved Expendable Launch Vehicle (EELV) and also adopts JWST design heritage. The ATLAST technology development plan is supported with funding from NASA's Astrophysics Strategic Mission Concept Study program, the Goddard Space Flight Center, the Marshall Space Flight Center, the Jet Propulsion Laboratory (Caltech) and related programs at Northrop Grumman Aerospace Systems and Ball Aerospace and Technology Corp.
In both designs, ATLAST will be able to be serviced, much like the HST has been. Using either a robotic ferry (the currently proposed method), or an astronaut crew flying in an Orion spacecraft (which will allow NASA to gain experience for future manned Solar System missions), instruments such as cameras would be replaced and returned to Earth for analysis and future upgrades. Like the HST and proposed JWST, ATLAST would be powered by solar panels.

ATLAST would either be launched from the Kennedy Space Center's Launch Pad 39A by an Ares V rocket or, if the 9.2-meter design is adopted, from NASA facilities capable of launching EELVs. Much like the proposed Orion/Altair flights to the Moon, the Ares V will place ATLAST and the Earth Departure Stage (EDS) into a "parking" orbit, while engineers check out the systems of both the EDS and the ATLAST. Once cleared, the EDS will fire again and ATLAST will then begin a three-month journey to the Sun-Earth L₂ Point, entering a so-called "halo orbit" around the point once it is reached. While en route to the Sun-Earth L₂ Point, the segmented versions of the telescope would deploy their optics.
Servicing missions, launched every 5 to 7 years, would allow astronomers to upgrade the ATLAS Telescope with new instruments and technologies. Like the HST, ATLAST should have a 20-year lifespan.
Credit: Northrop Grumman Aerospace Systems and NASA/STScI

The Chandra X-ray Observatory (CXO)

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At Launch Pad 39-B, the Chandra X-ray Observatory sits inside the payload bay of Space Shuttle Columbia, waiting for the doors to close.

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The Chandra X-ray Observatory in honor of Subrahmanyan Chandrasekhar, was launched and deployed by the Space Shuttle Columbia on July 23, 1999. The combination of high resolution, large collecting area, and sensitivity to higher energy X-rays will make it possible for Chandra to study extremely faint sources, sometimes strongly absorbed, in crowded fields. Chandra was boosted into an elliptical high-earth orbit that allows long-duration uninterrupted exposures of celestial objects.

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This photo shows the Chandra X-Ray Observatory (CXO), formerly Advanced X-Ray Astrophysics Facility (AXAF), High Resolution Mirror Assembly (HRMA) being removed from the test structure in the X-Ray Calibration Facility (XRCF) at the Marshall Space Flight Center (MSFC). The AXAF was renamed CXO in 1999. The CXO is the most sophisticated and the world's most powerful x-ray telescope ever built. It observes x-rays from high-energy regions of the universe, such as hot gas in the remnants of exploded stars. The HRMA, the heart of the telescope system, is contained in the cylindrical "telescope" portion of the observatory. Since high-energy x-rays would penetrate a normal mirror, special cylindrical mirrors were created. The two sets of four nested mirrors resemble tubes within tubes. Incoming x-rays graze off the highly polished mirror surface and are furneled to the instrument section for detection and study. MSFC's XRCF is the world's largest, most advanced laboratory for simulating x-ray emissions from distant celestial objects. It produces a space-like environment in which components related to x-ray telescope imaging are tested and the quality of their performances in space is predicted. TRW, Inc. was the prime contractor for the development of the CXO and NASA's MSFC was responsible for its project management. The Smithsonian Astrophysical Observatory controls science and flight operations of the CXO for NASA from Cambridge, Massachusetts.
Credit: NASA

The New Horizons spacecraft near Pluto and Charon in July 2015

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Artist's concept of the New Horizons spacecraft as it approaches Pluto and its largest moon, Charon, in July 2015. The craft's miniature cameras, radio science experiment, ultraviolet and infrared spectrometers and space plasma experiments will characterize the global geology and geomorphology of Pluto and Charon, map their surface compositions and temperatures, and examine Pluto's atmosphere in detail. The spacecraft's most prominent design feature is a nearly 7-foot (2.1-meter) dish antenna, through which it will communicate with Earth from as far as 4.7 billion miles (7.5 billion kilometers) away.
Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute