Hubble Catches a Dusty Spiral in Virgo

This magnificent new image taken with the NASA/ESA Hubble Space Telescope shows the edge-on spiral galaxy NGC 4206, located about 70 million light-years away from Earth in the constellation of Virgo.

Captured here are vast streaks of dust, some of which are obscuring the central bulge, which can just be made out in the center of the galaxy. Towards the edges of the galaxy, the scattered clumps, which appear blue in this image, mark areas where stars are being born. The bulge, on the other hand, is composed mostly of much older, redder stars, and very little star formation takes place.

NGC 4206 was imaged as part of a Hubble snapshot survey of nearby edge-on spiral galaxies to measure the effect that the material between the stars — known as the interstellar medium — has on light as it travels through it. Using its Advanced Camera for Surveys, Hubble can reveal information about the dusty material and hydrogen gas in the cold parts of the interstellar medium. Astronomers are then able to map the absorption and scattering of light by the material — an effect known as extinction — which causes objects to appear redder to us, the observers.

NGC 4206 is visible with most moderate amateur telescopes at 13th magnitude. It was discovered by Hanoverian-born British astronomer, William Herschel on April 17, 1784.

Image Credit: ESA/Hubble & NASA, Nick Rose

Explanation from: http://www.nasa.gov/content/goddard/hubble-catches-a-dusty-spiral-in-virgo/

NASA’s NuSTAR Telescope Discovers Shockingly Bright Dead Star

Astronomers have found a pulsating, dead star beaming with the energy of about 10 million suns. This is the brightest pulsar – a dense stellar remnant left over from a supernova explosion – ever recorded. The discovery was made with NASA's Nuclear Spectroscopic Telescope Array, or NuSTAR.

"You might think of this pulsar as the 'Mighty Mouse' of stellar remnants," said Fiona Harrison, the NuSTAR principal investigator at the California Institute of Technology in Pasadena, California. "It has all the power of a black hole, but with much less mass."

The discovery appears in a new report in the Thursday Oct. 9 issue of the journal Nature.

The surprising find is helping astronomers better understand mysterious sources of blinding X-rays, called ultraluminous X-ray sources (ULXs). Until now, all ULXs were thought to be black holes. The new data from NuSTAR show at least one ULX, about 12 million light-years away in the galaxy Messier 82 (M82), is actually a pulsar.

"The pulsar appears to be eating the equivalent of a black hole diet," said Harrison. "This result will help us understand how black holes gorge and grow so quickly, which is an important event in the formation of galaxies and structures in the universe."

ULXs are generally thought to be black holes feeding off companion stars -- a process called accretion. They also are suspected to be the long-sought after "medium-size" black holes – missing links between smaller, stellar-size black holes and the gargantuan ones that dominate the hearts of most galaxies. But research into the true nature of ULXs continues toward more definitive answers.

NuSTAR did not initially set out to study the two ULXs in M82. Astronomers had been observing a recent supernova in the galaxy when they serendipitously noticed pulses of bright X-rays coming from the ULX known as M82 X-2. Black holes do not pulse, but pulsars do.

Pulsars belong to a class of stars called neutron stars. Like black holes, neutron stars are the burnt-out cores of exploded stars, but puny in mass by comparison. Pulsars send out beams of radiation ranging from radio waves to ultra-high-energy gamma rays. As the star spins, these beams intercept Earth like lighthouse beacons, producing a pulsed signal.

"We took it for granted that the powerful ULXs must be massive black holes," said lead study author Matteo Bachetti, of the University of Toulouse in France. "When we first saw the pulsations in the data, we thought they must be from another source."

NASA's Chandra X-ray Observatory and Swift satellite also have monitored M82 to study the same supernova, and confirmed the intense X-rays of M82 X-2 were coming from a pulsar.

"Having a diverse array of telescopes in space means that they can help each other out," said Paul Hertz, director of NASA's astrophysics division in Washington. "When one telescope makes a discovery, others with complementary capabilities can be called in to investigate it at different wavelengths."

The key to NuSTAR's discovery was its sensitivity to high-energy X-rays, as well as its ability to precisely measure the timing of the signals, which allowed astronomers to measure a pulse rate of 1.37 seconds. They also measured its energy output at the equivalent of 10 million suns, or 10 times more than that observed from other X-ray pulsars. This is a big punch for something about the mass of our sun and the size of Pasadena.

How is this puny, dead star radiating so fiercely? Astronomers are not sure, but they say it is likely due to a lavish feast of the cosmic kind. As is the case with black holes, the gravity of a neutron star can pull matter off companion stars. As the matter is dragged onto the neutron star, it heats up and glows with X-rays. If the pulsar is indeed feeding off surrounding matter, it is doing so at such an extreme rate to have theorists scratching their heads.

Astronomers are planning follow-up observations with NASA's NuSTAR, Swift and Chandra spacecraft to find an explanation for the pulsar’s bizarre behavior. The NuSTAR team also will look at more ULXs, meaning they could turn up more pulsars. At this point, it is not clear whether M82 X-2 is an oddball or if more ULXs beat with the pulse of dead stars. NuSTAR, a relatively small telescope, has thrown a big loop into the mystery of black holes.

“In the news recently, we have seen that another source of unusually bright X-rays in the M82 galaxy seems to be a medium-sized black hole," said astronomer Jeanette Gladstone of the University of Alberta, Canada, who is not affiliated with the study. "Now, we find that the second source of bright X-rays in M82 isn’t a black hole at all. This is going to challenge theorists and pave the way for a new understanding of the diversity of these fascinating objects."

Image Credit: NASA/JPL-Caltech

Explanation from: http://www.nasa.gov/press/2014/october/nasa-s-nustar-telescope-discovers-shockingly-bright-dead-star/index.html

Flying Through an Aurora

European Space Agency astronaut Alexander Gerst posted this photograph taken from the International Space Station to social media on Aug. 29, 2014, writing, "words can't describe how it feels flying through an #aurora. I wouldn't even know where to begin…."

Crewmembers on the space station photograph the Earth from their unique point of view located 200 miles above the surface. Photographs record how the planet is changing over time, from human-caused changes like urban growth and reservoir construction, to natural dynamic events such as hurricanes, floods and volcanic eruptions. Crewmembers have been photographing Earth from space since the early Mercury missions beginning in 1961. The continuous images taken from the space station ensure this record remains unbroken.

On Tuesday, Sept. 9 aboard the space station, cosmonaut Max Suraev of Roscosmos takes the helm when Expedition 40 Commander Steve Swanson hands over control during a Change of Command Ceremony at 5:15 p.m. EDT. Suraev will lead Expedition 41 and stay in orbit until November with Gerst and NASA astronaut Reid Wiseman. Soyuz Commander Alexander Skvortsov, Swanson and Flight Engineer Oleg Artemyev will complete their mission Wednesday, Sept. 10 at 7:01 p.m. when they undock in their Soyuz TMA-12M spacecraft from the Poisk docking compartment for a parachute-assisted landing on the steppe of Kazakhstan a little less than 3.5 hours later.

Image Credit: NASA/ESA/Alexander Gerst

Explanation from: http://www.nasa.gov/content/flying-through-an-aurora/

An Astronaut's View from Space

NASA astronaut Reid Wiseman tweeted this photo from the International Space Station on Tuesday morning, September 2, 2014. "My favorite views from space – just past sunrise over the ocean," the Expedition 40 astronaut tweeted.

The Expedition 40 crew has been busy aboard the Space Station, recently performing health checks and humanoid robot upgrades. In the meantime, a trio of orbital residents is packing up gear as they prepare to return home in less than two weeks. Commander Steve Swanson powered down and stowed Robonaut 2 after wrapping up its mobility upgrades this week. He installed new legs on the humanoid robot including external and internal gear as well as cables. This sets the stage for more upgrades in the fall before Robonaut takes its first steps as an assistant crew member. Robonaut was designed to enhance crew productivity and safety while also aiding people on Earth with physical disabilities.

Image Credit: NASA/Reid Wiseman
Explanation from: http://www.nasa.gov/content/an-astronauts-view-from-space/

A Stellar Birthplace Shaped and Destroyed by Energetic Offspring

The little-known cloud of cosmic gas and dust called Gum 15 is the birthplace and home of hot young stars. Beautiful and deadly, these stars mould the appearance of the nebula from which they formed and, as they progress into adulthood, will eventually also destroy it.

This image was taken as part of the ESO Cosmic Gems programme using the Wide Field Imager on the MPG/ESO 2.2-metre telescope at the La Silla Observatory in Chile. It shows Gum 15, located in the constellation of Vela (The Sails), some 3000 light-years from Earth. This glowing cloud is a striking example of an HII region. Such clouds form some of the most spectacular astronomical objects we can see; for example the Eagle Nebula (which includes the feature nicknamed “The Pillars of Creation”), the great Orion Nebula, and this less famous example, Gum 15.

Hydrogen (H) is the most common element in the Universe, and can be found in virtually every environment investigated by astronomers. HII regions are different because they contain substantial amounts of ionised hydrogen — hydrogen atoms that have been stripped of their electrons through high energy interactions with ultraviolet photons — particles of light. As the ionised hydrogen nuclei recapture electrons they release light at different characteristic wavelengths. It is one of these that gives nebulae such as Gum 15 their reddish glow — a glow which astronomers call hydrogen alpha (Hα).

In HII regions the ionising photons come from the young hot stars within the region, and Gum 15 is no exception. At the centre of this image you can see one of the culprits: the star HD 74804, the brightest member of a cluster of stars known as Collinder 197.

The clumpy, irregular appearance that enhances this nebula’s beauty is not unusual for a HII region and is again a result of the stars within. HII regions have diverse shapes because the distribution of stars and gas inside them is so irregular. Adding to Gum 15’s interesting shape are the forked dark patch of obscuring dust visible in the centre of this image and some dim blue reflection structures crossing it. This dust feature makes the nebula resemble a larger and fainter version of the better known Trifid Nebula (Messier 20), although in this case the name Bifid Nebula might be more apposite.

An HII region like this one might give birth to thousands of stars over a period of several million years. Some of these stars cause it to glow and sculpt its shape, and it is these stars that will eventually destroy it. Once the newly minted stars have passed through their infant stages, strong winds of particles will stream away from these large stars, sculpting and dispersing the gases around them, and when the most massive of these stars begin to die, Gum 15 will die with them. Some stars are so large that they will go out with a bang, exploding as supernovae and dispersing the regions last traces of HII, leaving behind just a cluster of infant stars.

Image Credit: ESO
Explanation from: http://www.eso.org/public/news/eso1420/

Lives and Deaths of Sibling Stars

In this striking new image from ESO’s La Silla Observatory in Chile young stars huddle together against a backdrop of clouds of glowing gas and lanes of dust. The star cluster, known as NGC 3293, would have been just a cloud of gas and dust itself about ten million years ago, but as stars began to form it became the bright group of stars we see here. Clusters like this are celestial laboratories that allow astronomers to learn more about how stars evolve.

This beautiful star cluster, NGC 3293, is found 8000 light-years from Earth in the constellation of Carina (The Keel). This cluster was first spotted by the French astronomer Nicolas-Louis de Lacaille in 1751, during his stay in what is now South Africa, using a tiny telescope with an aperture of just 12 millimetres. It is one of the brightest clusters in the southern sky and can be easily seen with the naked eye on a dark clear night.

Star clusters like NGC 3293 contain stars that all formed at the same time, at the same distance from Earth and out of the same cloud of gas and dust, giving them the same chemical composition. As a result clusters like this are ideal objects for testing stellar evolution theory.

Most of the stars seen here are very young, and the cluster itself is less than 10 million years old. Just babies on cosmic scales if you consider that the Sun is 4.6 billion years old and still only middle-aged. An abundance of these bright, blue, youthful stars is common in open clusters like NGC 3293, and, for example, in the better known Kappa Crucis cluster, otherwise known as the Jewel Box or NGC 4755.

These open clusters each formed from a giant cloud of molecular gas and their stars are held together by their mutual gravitational attraction. But these forces are not enough to hold a cluster together against close encounters with other clusters and clouds of gas as the cluster’s own gas and dust dissipates. So, open clusters will only last a few hundred million years, unlike their big cousins, the globular clusters, which can survive for billions of years, and hold on to far more stars.

Despite some evidence suggesting that there is still some ongoing star formation in NGC 3293, it is thought that most, if not all, of the nearly fifty stars in this cluster were born in one single event. But even though these stars are all the same age, they do not all have the dazzling appearance of a star in its infancy; some of them look positively elderly, giving astronomers the chance to explore how and why stars evolve at different speeds.

Take the bright orange star at the bottom right of the cluster. This huge star, a red giant, would have been born as one of the biggest and most luminous of its litter, but bright stars burn out fast. As the star used up the fuel at its core its internal dynamics changed and it began to swell and cool, becoming the red giant we now observe. Red giants are reaching the end of their life cycle, but this red giant’s sister stars are still in what is known as the pre-main-sequence — the period before the long, stable, middle period in a star’s life. We see these stars in the prime of their life as hot, bright and white against the red and dusty background.

Image Credit: ESO/G. Beccari
Explanation from: http://www.eso.org/public/news/eso1422/

In Search of Space

At 5000 metres above sea level, high upon the Chajnantor Plateau in Chile, the antennas of the ALMA Observatory peer skywards, scanning the Universe for clues to our cosmic origins. This plateau is one of the highest observatory sites on Earth.

Visible amongst the thousands of stars on the right side of this image are the Small and Large Magellanic Clouds, appearing as luminous smudges in the sky. These cloud-like objects are both galaxies — two of the closest galactic neighbours to our galaxy, the Milky Way.

ALMA's main aim is to observe the coldest and most ancient objects in the cosmos — known as the "cold Universe". The array measures radiation emitted in the millimetre and submillimetre wavelengths, which lie in between infrared and radio waves in the electromagnetic spectrum. It features 66 mobile antennas which can be moved and configured over the ALMA site to meet the scientists' requirements, making it the biggest astronomical experiment in existence.

This amazing picture of the ALMA landscape was taken by ESO Photo Ambassador Stéphane Guisard, an optics engineer at the European Southern Observatory's Very Large Telescope in the Atacama Desert, Chile.

Image Credit: ESO/S. Guisard
Explanation from: http://www.eso.org/public/images/potw1431a/

VST snaps a very detailed view of the Triangulum Galaxy

The VLT Survey Telescope (VST) at ESO’s Paranal Observatory in Chile has captured this beautifully detailed image of the galaxy Messier 33, often called the Triangulum Galaxy. This nearby spiral, the second closest large galaxy to our own galaxy, the Milky Way, is packed with bright star clusters, and clouds of gas and dust. This picture is amongst the most detailed wide-field views of this object ever taken and shows the many glowing red gas clouds in the spiral arms with particular clarity.

Image Credit: ESO
Explanation from: http://www.eso.org/public/images/eso1424a/

Rosetta's Target Up Close

Close up detail focusing on a smooth region on the ‘base’ of the ‘body’ section of comet 67P/Churyumov-Gerasimenko. The image was taken by Rosetta’s Onboard Scientific Imaging System (OSIRIS) on August 6, 2014. The image clearly shows a range of features, including boulders, craters and steep cliffs. The image was taken from a distance of 80 miles (130 kilometers) and the image resolution is 8 feet (2.4 meters) per pixel.

The three U.S. instruments aboard the spacecraft are the Microwave Instrument for Rosetta Orbiter (MIRO), an ultraviolet spectrometer called Alice, and the Ion and Electron Sensor (IES). They are part of a suite of 11 science instruments aboard the Rosetta orbiter.

MIRO is designed to provide data on how gas and dust leave the surface of the nucleus to form the coma and tail that gives comets their intrinsic beauty. Studying the surface temperature and evolution of the coma and tail provides information on how the comet evolves as it approaches and leaves the vicinity of the sun.

Alice will analyze gases in the comet's coma, which is the bright envelope of gas around the nucleus of the comet developed as a comet approaches the sun. Alice also will measure the rate at which the comet produces water, carbon monoxide and carbon dioxide. These measurements will provide valuable information about the surface composition of the nucleus.

NASA also provided part of the electronics package for the Double Focusing Mass Spectrometer, which is part of the Swiss-built Rosetta Orbiter Spectrometer for Ion and Neutral Analysis (ROSINA) instrument. ROSINA will be the first instrument in space with sufficient resolution to be able to distinguish between molecular nitrogen and carbon monoxide, two molecules with approximately the same mass. Clear identification of nitrogen will help scientists understand conditions at the time the solar system was formed.

U.S. scientists are partnering on several non-U.S. instruments and are involved in seven of the mission's 21 instrument collaborations. NASA's Deep Space Network is supporting ESA's Ground Station Network for spacecraft tracking and navigation.

Launched in March 2004, Rosetta was reactivated in January 2014 after a record 957 days in hibernation. Composed of an orbiter and lander, Rosetta's objectives upon arrival at comet 67P/Churyumov-Gerasimenko in August are to study the celestial object up close in unprecedented detail, prepare for landing a probe on the comet's nucleus in November, and track its changes as it sweeps past the sun.

Comets are time capsules containing primitive material left over from the epoch when the sun and its planets formed. Rosetta's lander will obtain the first images taken from a comet's surface and will provide the first analysis of a comet's composition by drilling into the surface. Rosetta also will be the first spacecraft to witness at close proximity how a comet changes as it is subjected to the increasing intensity of the sun's radiation. Observations will help scientists learn more about the origin and evolution of our solar system and the role comets may have played in seeding Earth with water, and perhaps even life.

Image Credit: ESA/Rosetta/MPS for OSIRIS Team
Explanation from: http://www.nasa.gov/content/rosettas-target-up-close/

Comet 67P/Churyumov-Gerasimenko

Comet 67P/Churyumov-Gerasimenko by Rosetta’s OSIRIS narrow-angle camera on 3 August from a distance of 285 km. The image resolution is 5.3 metres/pixel.

Image Credit & Copyright: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

Aurora Australis

One of the more spectacular scenes of the aurora australis was photographed by one of the Expedition 40 crew members aboard the International Space Station from an altitude of approximately 223 nautical miles

Image Credit: NASA

Hubble Sees a Galaxy With a Glowing Heart

This view, captured by the NASA/ESA Hubble Space Telescope, shows a nearby spiral galaxy known as NGC 1433. At about 32 million light-years from Earth, it is a type of very active galaxy known as a Seyfert galaxy — a classification that accounts for 10% of all galaxies. They have very bright, luminous centers that are comparable in brightness to that of our entire galaxy, the Milky Way.

Galaxy cores are of great interest to astronomers. The centers of most, if not all, galaxies are thought to contain a supermassive black hole, surrounded by a disk of in-falling material.

NGC 1433 is being studied as part of a survey of 50 nearby galaxies known as the Legacy ExtraGalactic UV Survey (LEGUS). Ultraviolet radiation is observed from galaxies, mainly tracing the most recently formed stars. In Seyfert galaxies, ultraviolet light is also thought to emanate from the accretion discs around their central black holes. Studying these galaxies in the ultraviolet part of the spectrum is incredibly useful to study how the gas is behaving near the black hole. This image was obtained using a mix of ultraviolet, visible, and infrared light.

LEGUS will study a full range of properties from a sample of galaxies, including their internal structure. This Hubble survey will provide a unique foundation for future observations with the James Webb Space Telescope (JWST) and the Atacama Large Millimeter/submillimeter Array (ALMA). ALMA has already caught unexpected results relating to the center of NGC 1433, finding a surprising spiral structure in the molecular gas close to the center of NGC 1433. The astronomers also found a jet of material flowing away from the black hole, extending for only 150 light-years — the smallest such molecular outflow ever observed in a galaxy beyond our own.

Image Credit: ESA/Hubble & NASA

Explanation from: http://www.nasa.gov/content/goddard/hubble-sees-a-galaxy-with-a-glowing-heart/

Storm Cell over the Southern Appalachian Mountains

This storm cell photo was taken from NASA's high-altitude ER-2 aircraft on May 23, 2014, during a study aimed at gaining a better understanding of precipitation over mountainous terrain. The Integrated Precipitation and Hydrology Experiment, or IPHEx, field campaign is part of the ground validation effort for the Global Precipitation Measurement (GPM) mission, an international satellite mission led by NASA and the Japan Aerospace Exploration Agency. GPM's Core Observatory launched Feb. 27, 2014, to provide next-generation observations of rain and snow worldwide every three hours. But to get accurate measurements from space, scientists have to understand what is happening on the ground.

For the six-week IPHEx field campaign over the southern Appalachian mountains, the NASA team and their partners at Duke University and NOAA's Hydrometeorological Test Bed set up ground stations with rain gauges and ground radar throughout western North Carolina. In addition to the ground sites, they also collected data sets from satellites and two aircraft.

The NASA ER-2 aircraft that deployed to Robins Air Force Base in Warner Robins, Georgia, was able to fly when rain was in the air. The ER-2's cruising altitude of 65,000 feet kept it well above the storm systems it was observing, allowing it to act as a proxy-satellite. The aircraft carried a suite of instruments, including three that took measurements similar to those taken by GPM's Core Observatory.

Image Credit: NASA / Stu Broce
Explanation from: http://www.nasa.gov/content/storm-cell-over-the-southern-appalachian-mountains/

Tornado and Lightning in Nebraska

Video Credit & Copyright: Greg Johnson

Spectacular views of V838 Monocerotis light echo in 2005 and 2006

These images show the evolution of the light echo around the star V838 in the constellation of Monoceros. They were taken by the Hubble Advanced Camera for Surveys in November 2005 (left) and again in September 2006 (right). The numerous whorls and eddies in the interstellar dust are particularly noticeable. Possibly they have been produced by the effects of magnetic fields in the space between the stars.

Image Credit: NASA, ESA and H. Bond (STScI)

Hubble Eyes Golden Rings of Star Formation

Taking center stage in this new NASA/ESA Hubble Space Telescope image is a galaxy known as NGC 3081, set against an assortment of glittering galaxies in the distance. Located in the constellation of Hydra (The Sea Serpent), NGC 3081 is located over 86 million light-years from us. It is known as a type II Seyfert galaxy, characterized by its dazzling nucleus.

NGC 3081 is seen here nearly face-on. Compared to other spiral galaxies, it looks a little different. The galaxy's barred spiral center is surrounded by a bright loop known as a resonance ring. This ring is full of bright clusters and bursts of new star formation, and frames the supermassive black hole thought to be lurking within NGC 3081 — which glows brightly as it hungrily gobbles up in-falling material.

These rings form in particular locations known as resonances, where gravitational effects throughout a galaxy cause gas to pile up and accumulate in certain positions. These can be caused by the presence of a "bar" within the galaxy, as with NGC 3081, or by interactions with other nearby objects. It is not unusual for rings like this to be seen in barred galaxies, as the bars are very effective at gathering gas into these resonance regions, causing pile-ups which lead to active and very well-organized star formation.

Hubble snapped this magnificent face-on image of the galaxy using the Wide Field Planetary Camera 2. This image is made up of a combination of ultraviolet, optical, and infrared observations, allowing distinctive features of the galaxy to be observed across a wide range of wavelengths.

Image Credit: ESA/Hubble & NASA, R. Buta (University of Alabama)

Explanation from: http://www.nasa.gov/content/goddard/hubble-eyes-golden-rings-of-star-formation/

A stream of plasma burst out from the Sun

A stream of plasma burst out from the Sun, but since it lacked enough force to break away, most of it fell back into the Sun (May 27, 2014). The video, seen in a combination of two wavelengths of extreme ultraviolet light, covers a little over two hours. This eruption was minor and such events occur almost every day on the Sun and suggest the kind of dynamic activity being driven by powerful magnetic forces near the Sun's surface.

Image Credit: NASA/Solar Dynamics Observatory

NGC 604 in Galaxy M33

This is a Hubble Space Telescope image of a vast nebula called NGC 604, which lies in the neighboring spiral galaxy M33, located 2.7 million light-years away in the constellation Triangulum.

Image Credit: Hui Yang (University of Illinois) and NASA/ESA

30 Doradus in Ultraviolet, Visible, and Red Light

This image of hundreds of brilliant blue stars wreathed by warm glowing clouds is the most detailed view of the largest stellar nursery in our local galactic neighborhood. The stellar grouping, called R136, is only a few million years old and resides in the 30 Doradus Nebula, a turbulent star-birth region in the Large Magellanic Cloud (LMC), a satellite galaxy of our Milky Way. There is no known star-forming region in our galaxy as large or as prolific as 30 Doradus. Many of the diamond-like icy blue stars are among the most massive stars known. Several of them are over 100 times more massive than our Sun.

The image, taken in ultraviolet, visible, and red light by Hubble's Wide Field Camera 3, spans about 100 light-years. The nebula is close enough to Earth that Hubble can resolve individual stars, giving astronomers important information about the birth and evolution of stars in the universe. 

Image Credit: NASA, ESA, F. Paresce (INAF-IASF, Bologna, Italy), R. O'Connell (University of Virginia, Charlottesville), and the Wide Field Camera 3 Science Oversight Committee
Explanation from: http://www.spacetelescope.org/images/opo0932c/

Hubble Mosaic of the Majestic Sombrero Galaxy

NASA/ESA Hubble Space Telescope has trained its razor-sharp eye on one of the universe's most stately and photogenic galaxies, the Sombrero galaxy, Messier 104 (M104). The galaxy's hallmark is a brilliant white, bulbous core encircled by the thick dust lanes comprising the spiral structure of the galaxy. As seen from Earth, the galaxy is tilted nearly edge-on. We view it from just six degrees north of its equatorial plane. This brilliant galaxy was named the Sombrero because of its resemblance to the broad rim and high-topped Mexican hat.

At a relatively bright magnitude of +8, M104 is just beyond the limit of naked-eye visibility and is easily seen through small telescopes. The Sombrero lies at the southern edge of the rich Virgo cluster of galaxies and is one of the most massive objects in that group, equivalent to 800 billion suns. The galaxy is 50,000 light-years across and is located 28 million light-years from Earth.

Image Credit: NASA/ESA and The Hubble Heritage Team STScI/AURA)

Explanation from: http://www.spacetelescope.org/images/opo0328a/

Cumulonimbus Cloud over Texas

A little later, as the sunset, the storm looks quite different. This kind of complete view of a thunderstorm cloud is typical of the US Great Plains.

Texas, United States

May, 2012

Image Credit & Copyright: Kay Cunninghan

Space Guide: NGC 1566

This new Hubble image shows NGC 1566, a beautiful galaxy located approximately 40 million light-years away in the constellation of Dorado (The Dolphinfish). NGC 1566 is an intermediate spiral galaxy, meaning that while it does not have a well defined bar-shaped region of stars at its centre — like barred spirals — it is not quite an unbarred spiral either.

The small but extremely bright nucleus of NGC 1566 is clearly visible in this image, a telltale sign of its membership of the Seyfert class of galaxies. The centres of such galaxies are very active and luminous, emitting strong bursts of radiation and potentially harbouring supermassive black holes that are many millions of times the mass of the Sun.

NGC 1566 is not just any Seyfert galaxy; it is the second brightest Seyfert galaxy known. It is also the brightest and most dominant member of the Dorado Group, a loose concentration of galaxies that together comprise one of the richest galaxy groups of the southern hemisphere. This image highlights the beauty and awe-inspiring nature of this unique galaxy group, with NGC 1566 glittering and glowing, its bright nucleus framed by swirling and symmetrical lavender arms.

This image was taken by Hubble's Wide Field Camera 3 (WFC3) in the near-infrared part of the spectrum.

Image Credit: NASA & ESA
Explanation from: http://www.spacetelescope.org/images/potw1422a/

Brisbane Sunset Moonset

In skies over Brisbane at the southeastern corner of Queensland, Australia, Planet Earth, the Sun and New Moon set together on April 29, 2014. There the celestial line-up, the first solar eclipse of 2014, was seen as a partial solar eclipse. This dramatic composite is a digital stack of images taken about 5 minutes apart with telephoto lens and solar filter. It follows the eclipse in progress, approaching a western horizon where crepuscular rays from cloud banks in silhouette joined the silhouetted Moon. From Brisbane, the maximum eclipse phase with the Moon covering about 25% of the Sun occurred just after sunset. Only from a remote spot on the continent of Antarctica was it even possible to see the eclipse in its brief annular phase, the entire dark lunar disk surrounded by a thin, bright ring of fire.

Image Credit & Copyright: Stephen Mudge

Explanation from: http://apod.nasa.gov/apod/ap140501.html

Lunar Eclipse over Waterton Lakes National Park

Waterton Lakes National Park, Alberta, Canada

April 15, 2014

Image Credit & Copyright: Yuichi Takasaka

Along the Western Veil

Delicate in appearance, these filaments of shocked, glowing gas, draped in planet Earth's sky toward the constellation of Cygnus, make up the western part of the Veil Nebula. The Veil Nebula itself is a large supernova remnant, an expanding cloud born of the death explosion of a massive star. Light from the original supernova explosion likely reached Earth over 5,000 years ago. Blasted out in the cataclysmic event, the interstellar shock wave plows through space sweeping up and exciting interstellar material. The glowing filaments are really more like long ripples in a sheet seen almost edge on, remarkably well separated into atomic hydrogen (red) and oxygen (blue-green) gas. Also known as the Cygnus Loop, the Veil Nebula now spans nearly 3 degrees or about 6 times the diameter of the full Moon. While that translates to over 70 light-years at its estimated distance of 1,500 light-years, this wide image of the western portion spans about half that distance. Brighter parts of the western Veil are recognized as separate nebulae, including The Witch's Broom (NGC 6960) along the top of this view and Pickering's Triangle (NGC 6979) below and right of center.

Image Credit: Oliver Czernetz, Digitized Sky Survey

Explanation from: http://apod.nasa.gov/apod/ap140404.html

M78 and Reflecting Dust Clouds

An eerie blue glow and ominous columns of dark dust highlight M78 and other bright reflection nebula in the constellation of Orion. The dark filamentary dust not only absorbs light, but also reflects the light of several bright blue stars that formed recently in the nebula. Of the two reflection nebulas in this picture, the more famous nebula is M78, in the image center, while NGC 2071 can be seen to its lower left. The same type of scattering that colors the daytime sky further enhances the blue color. M78 is about five light-years across and visible through a small telescope. M78 appears above only as it was 1600 years ago, however, because that is how long it takes light to go from there to here. M78 belongs to the larger Orion Molecular Cloud Complex that contains the Great Nebula in Orion and the Horsehead Nebula.

Image Credit & Copyright: Ian Sharp
Explanation from: http://apod.nasa.gov/apod/ap140326.html

Perseid Meteors over Oakland

Oakland, Ontario, Canada

August 11, 2013

Image Credit & Copyright: Darryl Van Gaal

IC 1848: The Soul Nebula

The Soul Nebula houses several open clusters of stars, a large radio source known as W5, and huge evacuated bubbles formed by the winds of young massive stars. Located about 6,500 light years away, the Soul Nebula spans about 100 light years and is usually imaged next to its celestial neighbor the Heart Nebula (IC 1805). This picture appears mostly red due to the emission of a specific color of light emitted by excited hydrogen gas.

Image Credit & Copyright: Bob Andersson
Explanation from: http://apod.nasa.gov/apod/ap130415.html

Star Forming Region NGC 3582

What's happening in the NGC 3582 nebula? Bright stars and interesting molecules are forming. The complex nebula resides in the star forming region called RCW 57. Visible in this image are dense knots of dark interstellar dust, bright stars that have formed in the past few million years, fields of glowing hydrogen gas ionized by these stars, and great loops of gas expelled by dying stars. A detailed study of NGC 3582, also known as NGC 3584 and NGC 3576, uncovered at least 33 massive stars in the end stages of formation, and the clear presence of the complex carbon molecules known as polycyclic aromatic hydrocarbons (PAHs). PAHs are thought to be created in the cooling gas of star forming regions, and their development in the Sun's formation nebula five billion years ago may have been an important step in the development of life on Earth. This picture was taken at the Desert Hollow Observatory north of Phoenix, Arizona, USA.

Image Credit & Copyright: Desert Hollow Observatory
Explanation from: http://apod.nasa.gov/apod/ap130611.html

A Super Moon's Halo

A Full Perigee Moon rose as the Sun set in June 2013. At its closest to Earth it was, by just a bit, the year's brightest and largest Full Moon also known as a Super Moon. Seen from Punta Piedras, Argentina and the mouth of the Rio de La Plata, near Buenos Aires, the Super Moon's light created this magnificent circular lunar halo. Still, the size of a lunar halo is determined by the geometry of six sided water ice crystals in planet Earth's high, thin clouds. The crystals deflect the rays of moonlight more strongly through a minimum angle of 22 degrees. So this halo has an inner radius of 22 degrees, just like the halos of the less-than-super moons. Even more common than a Super Moon, beautiful 22 degree halos can be spotted at any time of year.

Image Credit & Copyright: Luis Argerich
Explanation from: http://apod.nasa.gov/apod/ap130628.html

Stellar Nursery in the arms of NGC 1672

The barred spiral galaxy NGC 1672, showing up clusters of hot young blue stars along its spiral arms, and clouds of hydrogen gas glowing in red. Delicate curtains of dust partially obscure and redden the light of the stars behind them. NGC 1672's symmetric look is emphasised by the four principal arms, edged by eye-catching dust lanes that extend out from the centre.

Image Credit: NASA, ESA
Explanation from: http://www.spacetelescope.org/images/heic0706a/

Ring Nebula (Messier 57)

From Earth’s perspective, the nebula looks like a simple elliptical shape with a shaggy boundary. However, new observations combining existing ground-based data with new NASA/ESA Hubble Space Telescope data show that the nebula is shaped like a distorted doughnut. This doughnut has a rugby-ball-shaped region of lower-density material slotted into in its central “gap”, stretching towards and away from us.

Image Credit: NASA, ESA, and C. Robert O’Dell (Vanderbilt University).
Explanation from: http://www.spacetelescope.org/images/heic1310a/

In the Heart of the Rosette Nebula

In the heart of the Rosette Nebula lies a bright open cluster of stars that lights up the nebula. The stars of NGC 2244 formed from the surrounding gas only a few million years ago. This image taken in January 2014 using multiple exposures and very specific colors of Sulfur (shaded red), Hydrogen (green), and Oxygen (blue), captures the central region in tremendous detail. A hot wind of particles streams away from the cluster stars and contributes to an already complex menagerie of gas and dust filaments while slowly evacuating the cluster center. The Rosette Nebula's center measures about 50 light-years across, lies about 4,500 light-years away, and is visible with binoculars towards the constellation of the Unicorn (Monoceros).

Image Credit & Copyright: Don Goldman
Explanation from: http://apod.nasa.gov/apod/ap140311.html