A Near Record Ozone Hole in 2003

A Near Record Ozone Hole in 2003



As expected, the ozone hole near Earth's South Pole is back again this year.This year's hole, being slightly larger than North America, is larger than last year but short of the record set on 2000 September 10 Ozone is important because it shields us from damaging ultraviolet sunlight. Ozone is vulnerable, though, to CFCs and halons being released into the atmosphere. Inte national efforts to reduce the use of these damaging chemicals appear to be having a positive effect on their atmospheric abundance. The relatively large size of the ozone hole this year, however, is attributed partly to colder than normal air in the surrounding stratosphere. The above picture of the ozone hole was taken on September 11 by TOMS on board the orbiting Earth Probe satellite.

Apollo 12 Visits Surveyor 3

Apollo 12 Visits Surveyor 3



Apollo 12 was the second mission to land humans on the Moon.The landing site was picked to be near the location of Surveyor 3, a robot spacecraft that had landed on the Moon three years earlier.In the above photograph, taken by lunar module pilo Alan Bean,mission commander Pete Conrad jiggles the Surveyor spacecraft to see how firmly it is situated.The lunar module is visible in the distance. Apollo 12brought back many photographs and moon rocks. Among the milestones achieved byApollo 12 was the deployment of the Apollo Lunar Surface Experiments Package, which carried out many experiments including one that measured the solar wind.

X-Ray Moon

X-Ray Moon



This x-ray image of the Moonwas made by the orbitin ROSAT Röntgensatellit) Observatory in 1990.In this digital picture, pixel brightness corresponds to x-ray intensity.Consider the image in three parts:the bright hemisphere of the x-ray moon,the darker half of the moon,and the x-ray sky background.The bright lunar hemisphere shine in x-rays because it scattersx-rays emitted by the sun.The background sky has an x-rayglow in part due tothe myriad of distant, powerful active galaxies, unresolvedin the ROSAT picture but recently detected in Chandra Observator x-ray images.But why isn't the dark half of the moon completely dark NewChandra results also suggest that a few x-rays only seemto come from the shadowedlunar hemisphere.Instead, theyoriginate in Earth's geocorona o extendedatmosphere which surrounds the orbiting x-ray observatories.

Cold Comet Halley

Cold Comet Halley



While this may not be the most esthetic image o Comet Halleythat you have ever seen, it is likely the most unique.The tiny cluster of pixels circled is th famouscomet along its orbit over4 billion (4,000,000,000) kilometers or 2 AUfrom the Sun - a record distance for a comet observation.Its last passage throug our neck of the woods in 1986 Comet Halleypresently cruises through the dim reaches of the outer solarsystem, almost as far away as outermost gas giant Neptune, and shows nosign of activity.Captured in March, this negative image is a composite ofdigital exposures made with threeof ESO's Very Large Telescopes.The exposures are registered on th moving comet, so thepicture shows background stars and galaxies as elongated smudges.An earth-orbiting satellite appears as a dark streak at the top CometHalley is clearly extremely faint here, but large earthboundtelescopes will be able to followit as it grows fainter still, reachingthe most distant point in its orbit, more than 5 billion kilometers(35 AU) from the Sun, in 2023.

Reflections on the 1970s

Reflections on the 1970s



The 1970s areoften overlooked.In particular, the beautiful grouping of reflection nebula NGC 1977,NGC 1975, and NGC 1973 in Orion areoften overlooked in favor ofthe substantial stellar nursery better known as the Orion Nebula.Found along the sword of Orion just nort of thebright Orion Nebula complex, these nebulae are also associate with Orion's giantmolecular cloud which lies abou 1,500 light-years away, butare dominated by the characteristic blue color of interstellardust reflecting light from hot young stars.In this sharpcolor image a portion of the Orion Nebula appearsalong the bottom border with the cluste of reflection nebulaeat picture center.NGC 1977 stretches across the field just below center,separated from NGC 1973 (above right) and NGC 1975 (above left)by dark regions laced with faint red emission fromhydrogen atoms.Taken together, the dark regions suggest to many theshape of a running man.

An Unusual Event Over South Wales

An Unusual Event Over South Wales



Jon Burnett, a teenager from South Wales, UK, was photographing some friends skateboarding last week when the sky did something very strange. By diverting his camera, he was able to document this rare sky event and capture one of the more spectacular sky images yet recorded. Roughly four minutes later, he took another picture of the dispersing trail. What is it? Experts disagree. The first guess wasa sofa-sized rock that exploded as a daytime fireball, but perhaps a better hypothesis is an unusual airplane contrail reflecting the setting Sun Bright fireballs occur over someplace on Earth nearly every day. A separate bolide, likely even more dramatic, struck India only a few days ago. Editor's note: The APOD text was updated on Oct. 1.

The Sagittarius Dwarf Tidal Stream

The Sagittarius Dwarf Tidal Stream



Is our Milky Way Galaxy out to lunch? Recent wide field images and analyses now indicate that our home galaxy is actually still in the process of devouring its closest satellite neighbor. This unfortunate neighbor, the Sagittarius Dwarf galaxy, is now seen to be part of a larger Sagittarius Tidal Stream, a loose filament of stars, gas, and possibly dark matter that entangles the Milky Way. An artist's depiction of the stream is shown above. Speculation also holds that the Sagittarius Dwarf was once pulled through the Milky Way disk very close to our Sun's current location. An important resulting realization is that galaxies contain a jumble of clumps and filaments of both dim and dark matter.

Aurora Over the Chugach Mountains

Aurora Over the Chugach Mountains



Auroras can make spectacular sights. Photographed above, flowing green auroras help the Moon illuminate the serene Portage Lake and the snowy Chugach Mountains near Anchorage, Alaska, USA.Although auroras might first appear to be moonlit clouds, they only add light to the sky and do not block background stars from view. Called northern lights in the northern hemisphere, auroras are caused by collisions between charged particles from the magnetosphere and air moleculeshigh in the Earth's atmosphere.If viewed from space, auroras can be seen to glow in X-ray and ultraviolet light as well. Predictable auroras likely occur a few days after a powerful magnetic event has been seen on the Sun.

Our Galaxy in Stars, Gas, and Dust

Our Galaxy in Stars, Gas, and Dust



The disk of our MilkyWay Galaxy is home to hot nebulae, cold dust, and billions of stars. The red nebulae visible in the above contrast-enhanced picture are primarily emission nebulae, glowing clouds of hydrogengas heated by nearby, bright, young stars. The blue nebulae are primarily reflection nebulae, clouds of gas and fine dust reflecting the light of nearby bright stars. Perhaps the most striking, though, are the areas of darkness, including the Pipe Nebula visible on the image top left. These are lanes of thick dust, many times containing relatively cold molecular clouds of gas. Dust is so plentiful that it obscures the Galactic Center in visible light, hiding its true direction until discovered earlylast century. The diffuse glow comes from billions of older, fainter stars like our Sun,which are typically much older than any of the nebulae. Most of the mass of ourGalaxy remains in a form currentlyunknown.

Surveyor Slides

Surveyor Slides



"Safe!"

IC1340 in the Eastern Veil

IC1340 in the Eastern Veil



These ghostly filaments of interstellar gas are just a smallpart of th expansiveVeil Nebula, seen against a rich fieldof background stars in th long-neckedconstellatio Cygnus.Also known as th Cygnus Loop, the Veil Nebula is supernova remnant,the expanding debris cloud created by a stellarexplosion whose light first reached planet Earthfrom 5,000 to 10,000 years ago.About 1,400 light-years away,the entire nebula now appearsto span over 3 degrees onthe sky, nearly 6 times the apparent size of the full moon,but is faint and can be difficult to see in small telescopes.The region captured i thisbeautiful, deep, color imageis located at the southern tip of the Veil' easterncrescent.It covers about 10 light-years at the distance ofthe Veil and is cataloged as IC1340.

Logarithmic Spirals Isabel and M51

Logarithmic Spirals Isabel and M51



Uncomfortably clos hurricane Isabel (left)and 30 million light-yeardistant galaxy M51 actually don't have much in common.For starters, Isabel was hundreds of miles across, while M51 (th Whirlpool Galaxy)spans about 50,000 light-years making them vastlydissimilar in scale, not to mention the extremely differentphysical interactions which control thei formation an evolution.But they do look amazingly alike, both exhibiting the shape of a simpleand beautiful mathematical curve known as logarithmicspiral, a spiral whose separation grows in geometricway with increasing distance from the center.Also known as th equiangular spiral, growth spiral, and Bernoulli'sspiral or spira mirabilis, this curve' rich properties have fascinate mathematicianssince its discovery by 17th century philosophe Descartes.Intriguingly, this abstract shape is much more abundant in naturethan suggested by the striking visual comparison above.Logarithmic spirals also describe, for example, the arrangement o sunflowerseeds, the shapes of nautilus shells, and .. cauliflower.

M33 Spiral Galaxy in Triangulum

M33 Spiral Galaxy in Triangulum



The small constellatio Triangulumin the northern sky harborsthis magnificent face-on spiral galaxy, M33.Its popular names include the Pinwheel Galaxy or justthe Triangulum Galaxy.M33's diameter spans over 50,000 light-years, making it third largest inthe LocalGroup of galaxies after the Andromeda Galaxy (M31), and ourown Milky Way.About 3 million light-years from the Milky Way, M33lies very close to the Andromeda Galaxy an observersin these two galaxies would likely have spectacular views ofeach other's grand spiral star systems.As for the view from planet Earth, thi sharp27 frame mosaic of M33 nicely shows off blue star clustersand pinkish star forming regions which trace the galaxy'sloosely wound spiral arms.In fact, the cavernous NGC 604 is the brighteststar forming region seen here, visiblealong an arm arcing above and to the rightof the galaxy center.Like M31, M33's population of well-measured variable starshave helped make this nearby spiral cosmicyardstick fo establishingthe distance scale of the Universe.

Egging On the Autumnal Equinox

Egging On the Autumnal Equinox



Today is the autumnal equinox -- should eggs be able to stand on end? This long-standing myth loses much of its mystique after a demonstration that eggs can be made to stand on end during any day of the year. Pictured above, Dr. Phil Plait Sonoma St. U.) acting as the Bad Astronomer balanced three raw eggs on end in late October 1998. Later, more modestly, his wife balanced five more. The little-appreciated fact that most eggshells have small bumps on them makes this seemingly impossible task achievable. Although, during an equinox, every place on Earth experiences an equal length day and night (12 hours each), this fact has no practical effect on egg stability.

Opportunity Rockets Toward Mars

Opportunity Rockets Toward Mars



Next stop: Mars. Two months ago, the second of two missions to Mars was launched from Cape Canaveral, Florida, USA above a Boeing Delta II rocket.The Mars Exploration Rover dubbed Opportunity is expected to arrive at the red planet this coming January. Pictured above, an attached RocketCam (TM) captures Opportunityseparating from lower booster stages and rocketing off towardMars.Upon arriving, parachutes will deploy to slow the spacecraft and surrounding airbags will inflate. The balloon-like package will then bounce around the surface a dozen times or more before coming to a stop. The airbags will then deflate, the spacecraft will right itself, and the Opportunity rover will prepare to roll onto Mars. A first rover named Spirit was successfully launched on June 10 and will arrive at Mars a few weeks earlier. The robots Spirit and Opportunity are expected to cover as much as 40 metres per day, much more than Sojourner, their 1997 predecessor. Spirit and Opportunity will search for evidence of ancient Martian water, from which implications might be drawn about the possibility of ancient Martian life.

Inside the Eagle Nebula

Inside the Eagle Nebula



From afar, the whole thing looks like an Eagle. A closer look at the Eagle Nebula, however, shows the bright region is actually a window into the center of a larger dark shell of dust. Through this window, a brightly-lit workshop appears where a whole open cluster of stars is being formed. In this cavity tall pillars and round globules of dark dust and cold molecular gasremain where stars are still forming. Already visible are several young bright blue stars whose light and winds are burning away and pushing back the remaining filaments and walls of gas and dust. The Eagle emission nebula, tagged M16, lies about 6500 light years away, spans about 20 light-years, and is visible with binoculars toward the constellation of Serpens. The above picture combines three specific emitted colors and was taken with the 0.9-meter telescope on Kitt Peak, Arizona, USA.

Apollo 11 Catching Some Sun

Apollo 11 Catching Some Sun



Bright sunlightglints and long dark shadow dramatize thisimage of th lunar surfacetaken by Apollo 11 astronaut NeilArmstrong, the first to wal on the Moon.Pictured is the mission's lunar module, the Eagle,and spacesuited lunar module pilot Buzz Aldri unfurling a long sheet of foil also known as th Solar Wind Collector.Exposed facing the Sun, the foil trapped atoms streaming outwardin the solar wind, ultimately catching a sample o material from the Sun itself.Along with moon rocks and lunar soil samples, the solar wind collector wasreturned for analysisin earthbound laboratories.

Galileo's Europa

Galileo's Europa



Launched in 1989 and looping through the jovian system since late1995, the voyage of NASA' Galileospacecraft will soon come to an end.The spacecraft has bee targeted to plungedirectl intoJupiter this Sunday, September 21st, at about 30 miles per second.Its components will be vaporized in thegas giant's outer atmosphere.While Galileo's long voyage of explorationhas resulted in a spectacula scientificlegacy,the spacecraft's ultimate fate is related to perhapsits mos tantalizingdiscovery -- strong evidence for liquid oceanbeneath the frozen surface of Jupiter' moonEuropa.Galileo is now almost completely out of fuel for maneuvers,so this intentional collision with Jupiter will preventany unintentional future collision with Europaand the possibility of contaminating the jovian moon withmicrobes from Eart hardy enough to survive in interplanetary space Colorimage data from the Galileo mission recorded between1995 and 1998 was used to create this depiction ofEuropa's cracked and icy surface The insetshows dark reddish, disrupted regions dubbed Thera and Thrace.

Saturn by Three

Saturn by Three



Thes threeviews of Saturn wererecorded by the Hubble Space Telescope on March 7th of thisyear, as the southern hemisphere of the solar system's most gorgeousplanet reached its maximum 27 degree tilttoward Earth.The images use to constructthe false-color pictures were madethrough a combination o filters covering theelectromagnetic spectrum from ultraviolet (top), to visible (middle)and infrared (bottom) wavelengths highlighting differen features in the Saturnian atmospheric bands and rings.Well known for its bright ringsystem and large,mysterious moon Titan,gas gian Saturn isalso a planet with a dynamic atmosphere and high-speed winds.In fact, in the 1980s Voyagerspacecraft measured equatorialwinds of over 1,000 miles per hour.Giant storm systems,comparable in size to planet Earth itself, have been see erupting in Saturn's cloud tops.

The 2MASS Galaxy Sky

The 2MASS Galaxy Sky



Are the nearest galaxies distributed randomly?A plot of over one million of the brightest "extended sources" detected by the Two Micron All Sky Survey (2MASS) shows that they are not. The vast majority of these infrared extended sources are galaxies. Visible above is an incredible tapestry of structure that provides limits on how the universe formed and evolved. Many galaxies are gravitationally bound together to form clusters, which themselves are loosely bound into superclusters, which in turn are sometimes seen to align over even larger scale structures. In contrast, very bright stars inside our own Milky Way Galaxy cause the vertical blue sash.

Hurricane Isabel Approaches

Hurricane Isabel Approaches



Where will Hurricane Isabel go? One of the stronger storm systems of modern times appears headed for one the more populated seaboards on planet Earth -- the east coast of the USA. Hurricane Isabel, pictured yesteday as it passed east of the Bahamas, has flirted with category 5 status, the most powerful hurricane category.Hurricanes are huge swirling storms with cloudsystems typically larger than a state. Tropical cyclones, called hurricanes inEarth's Western Hemisphere and typhoons in the Eastern Hemisphere, get their immense energy from warm evaporated ocean water. As this water vapor cools andcondenses, it heats the air, lowers pressure and hence causes cooler air to comeswooshing in. Winds can reach over 250 kilometers per hour and become very dangerous. Much remains unknown abou cyclones, including how they are formed and the exact path they will take.

Globular Cluster M3

Globular Cluster M3



This huge ball of stars predates our Sun. Long before humankind evolved, before dinosaurs roamed, and even before our Earth existed, ancient globs of stars condensed and orbited a young Milky Way Galaxy. Of the 200 or so globular clusters that survive today, M3 is one of the largest and brightest, easily visible in the Northern hemisphere with binoculars. M3 contains about half a million stars, most of which are old and red. Light takes about 100,000 years to reach us from M3, which spans about 150 light years. The above picture is a composite of blue and red images.

The Crab Nebula from VLT

The Crab Nebula from VLT



The Crab Nebula, filled with mysterious filaments, is the result of a star that was seen to explode in 1054 AD. This spectacular supernova explosion was recorded by Chinese and (quite probably) Anasazi Indian astronomers. The filaments are mysterious because they appearto have less mass than expelled in the original supernovaand higher speed than expected from a free explosion.In the above picture taken recently from Very Large Telescope, the color indicates what is happening to the electrons in differentparts of the Crab Nebula.Red indicates the electrons are recombining with protons to form neutral hydrogen,while blue indicates the electrons are whirling around the magnetic fieldof the inner nebula. In the nebula's very center lies a pulsar: a neutron star rotating, in this case, 30 times a second.

NGC 3132 The Eight Burst Nebula

NGC 3132 The Eight Burst Nebula



It's the dim star, not the bright one, near the center o NGC 3132that created this odd but beautiful planetary nebula. Nicknamed the Eight-Burst Nebula and the Southern Ring Nebula, the glowing gas originated in the outer layers of a star like our Sun. In thi representativecolor picture, the hot blue pool of light seen surrounding this binary system is energized by the hot surface of the faint star. Although photographed to explore unusual symmetries, it's the asymmetries that help make this planetary nebula so intriguing. Neither the unusual shape of the surrounding cooler shell nor the structure and placements of the cool filamentary dust lanes running across NGC 3132are well understood.

A Note on the Perseus Cluster

A Note on the Perseus Cluster



A truly enormous collection of thousands of galaxies, th Perseus Cluster - like othe large galaxy clusters - isfilled with hot, x-ray emitting gas.The x-ray hot gas(not the individual galaxies) appearsin the left panel above, a false colo imagefrom the Chandra Observatory.The bright central source flanked by tw dark cavities isthe cluster's supermassive black hole.At right, the panel shows th x-ray imagedata specially processedto enhance contrasts and reveals a strikingly regularpattern of pressure wave rippling throughthe hot gas. In other words soundwaves, likely generated by bursts ofactivity from the black hole, are ringing through thePerseus Galaxy Cluster.Astronomers infer that these previously unknown sound waves are asource of energy which keeps the cluster gas so hot So what note is the Perseus Cluster playing?Estimates of the distance between the wave peaks and sound speedin the cluster gas suggeststhe cosmic note is about 57 octaves below B-flat above middle C.

NGC 3370 A Sharper View

NGC 3370 A Sharper View



Similar in size and grand design to ou ownMilky Way, spiral galaxy NGC 3370 lies about 100 millionlight-years away toward the constellation Leo.Recorde herein exquisite detail by the Hubble Space Telescope' Advanced Camera for Surveys,the big, beautiful face-on spiral does steal the show,but the sharp image also reveals an impressive array ofbackground galaxies in the field, strewn acrossthe more distant Universe.Looking within NGC 3370 theimage data has proved sharp enoughto study individual pulsating stars known a Cepheids whichcan be used to accurately determine this galaxy's distance.NGC 3370 was chosen for this study because in 1994the spiral galaxy was also home to a well studied stellarexplosion -- a type Ia supernova.Combining the known distance to thi standard candle supernova,based on the Cepheid measurements, with observationsof supernovae at even greater distances,can reveal the size and expansion rate of th Universeitself.

Aurora Over Clouds

Aurora Over Clouds



Aurorae usually occur high above the clouds. The auroral glow is created when fast-moving charged particles fromthe Earth's magnetosphere impact air molecules high in the Earth's atmosphere. An oxygen molecule, for example, will emit a green light when reacquiring an electron lost during a collision. The lowest part of an aurora will typically occur at 100 kilometers and up, while most clouds usually exist only below about 10 kilometers. The relative heights of clouds and auroras are shown clearly in the above picture taken last month from near Quebec City, Canada.The most likely time to see an aurora is around midnight.

A Gemini Sky

A Gemini Sky



Where will Gemini take us tonight?It is dusk and Gemini North, one of the largest telescopes on planet Earth, prepares to peer into the distant universe. Gemini's flexible 8.1-mirror has taken already effectively taken humanity to distant stars, nebulas, galaxies, and quasars, telling us about the geometry, composition, and evolution of our universe.The above picture is actually a composite of over 40 images taken while the Gemini dome rotated, later adding an image of the star field taken from the same location.The Gemini dome is not transparent -- it only appears so because it rotated during the exposures of this image.The constellations of Scorpius and Sagittarius can be seen above the dome, as well as the sweeping band of our Milky Way Galaxy,including the direction toward the Galactic center.Gemini North's twin, Gemini South, resides in Cerro Pachn, Chile. This night, 2003 August 19, Gemini North took us only into the outer Solar System, observing Pluto in an effort to better determine the composition of its thin atmosphere.

Stars and Dust of the Lagoon Nebula

Stars and Dust of the Lagoon Nebula



The large majestic Lagoon Nebula is home for many young stars and hot gas. Spanning 100 light years across while lying only about 5000 light years distant, the Lagoon Nebulae is so big and bright thatit can be seen without a telescope toward the constellation of Sagittarius. Many bright stars are visible from NGC 6530, an open cluster that formed in the nebula only several million years ago.The greater nebula, also known as M8 and NGC 6523, is named "Lagoon" for the band of dust seen to the left of the open cluster's center. A bright knot of gas and dust in the nebula's center is known as the Hourglass Nebula. The above picture is a digitally sharpened composite of exposures taken in specific colors of light emitted by sulfur (red), hydrogen (green), and oxygen (blue).Star formation continues in the Lagoon Nebula as witnessed by the many globules that exist there.

The Galactic Center in Infrared

The Galactic Center in Infrared



The center of our Galaxy is a busy place. In visible light, much of the Galactic Center is obscured by opaque dust. In infrared light, however, dust glows more and obscures less, allowing nearly one million stars to be recorded in the above photograph. The Galactic Center itself appears on the right and is located about 30,000 light years away towards the constellation of Sagittarius. The Galactic Plane of our Milky Way Galaxy, the plane in which the Sun orbits, is identifiable by the dark diagonal dust lane. The absorbing dust grains are created in the atmospheres of cool red-giant stars and grow in molecular clouds. The region directly surrounding the Galactic Center glows brightly in radio and high-energy radiation, and is thought to house a large black hole.

Jupiter Unpeeled

Jupiter Unpeeled



SliceJupiterfrom pole to pole, peel back its outer layer of clouds,stretch them onto a flat surface ... and for all yourtrouble you'd end up with something that looks a lot like this.Scrolling right will reveal the full picture a color mosaic o Jupiterfrom the Cassini spacecraft.The mosaic is actually a single frame from a fourteen framemovie constructed from image data recorded by Cassiniduring it leisurelyflyby of the solar system's largestplanet in late 2000 Theengaging movie approximatesJupiter's cloud motions over 24 jovian rotations.To make it, a series of observations coveringJupiter's complete circumference60 degrees north and southof the equator were combined in an animate cylindricalprojection map of the planet.As in the familiar rectangular-shaped wall maps of th Earth's surface, therelative sizes and shapes of features arecorrect near the equator but become progressively more distortedapproaching the polar regions.In the Cassini movie, which also features guest appearancesby moons Io an Europa, the smallest cloud structuresvisible at the equator are about 600 kilometers across.

SIRTF Streak

SIRTF Streak



Streaking skyward, Boeing Delta 2-Heavy rocket carries NASA' Space InfraRedTelescope Facility (SIRTF) aloft duringthe early morning hours of August 25th.The dramatic scene was recorded in a time exposure from the pierin Jetty Park at the northern end of Cocoa Beach, Florida,about 2.5 miles from the Cape Canaveral launch site.SIRTF (sounds like "sir tiff") will explore the distan Universe in infrared lightas the fourth and finalsatellite observatory in NASA' Great Observatories Program.The three other large astrophysics satellites were designedfor higher energies in the electromagnetic spectrum, with th Hubble Space Telescopeoperating near visible wavelengths, th Compton Gamma Ray Observatoryinstruments sensitive to gamma rays, and th Chandra Observatorydetecting cosmic x-rays.SIRTF has been launched into a Earth-trailingsolar orbit to reduce its exposure to infrared radiation fromour fair planet.Cooled by an on board supply o liquid helium,SIRTF's infrared detectors will operate at near absolute zerotemperatures.Presently, SIRTF's systems are undergoing a 90-day check out.

Composite Crab

Composite Crab



The Crab Pulsar, a city-sized, magnetize neutron starspinning 30 times a second,lies at the center of this composite image of the inner region ofthe well-known CrabNebula.The spectacular picture combines optical data (red) from th Hubble Space Telescopeand x-ray images (blue) from th ChandraObservatory, also used in the popula CrabPulsar movies.Like cosmicdynamo the pulsar powers the x-rayand optical emission from the nebula, acceleratingcharged particles and producing the eerie, glowing x-ray jets.Ring-like structures are x-ray emitting regions wherethe high energy particles slam into the nebular material.The innermost ring is about a light-year across.With more mass tha theSun and the density of a atomic nucleus,the spinning pulsar is the collapsed core of a massive starthat exploded, while the nebula is theexpanding remnant of the star's outer layers.The supernova explosion was witnessed i the year 1054.

Galactic Supernova Remnant IC 443

Galactic Supernova Remnant IC 443



About 8000 years ago, a star in our Galaxy exploded. Ancient humans might have noticed the supernova as a temporary star, but modern humans can see the expanding shell of gas even today. Pictured above, part of the shell of IC 443 is seen to be composed of complex filaments, some of which are impacting an existing molecular cloud. Here emission from shock-excited molecular hydrogen is allowing astronomers to study how fast moving supernova gas affects star formation in the cloud. Additionally, astronomers theorize that the impact accelerates some particles to velocities near the speed of light. Supernova remnant IC 443 is also known to shine brightly also in infrared and X-ray light.

Contemplating Mars

Contemplating Mars