Monday, March 16, 2015

A Total Eclipse at the End of the World

A Total Eclipse at the End of the World: APOD: 2015 March 15 - A Total Eclipse at the End of the World


Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2015 March 15


See Explanation. Clicking on the picture will download the highest resolution version available.
Explanation: Would you go to the end of the world to see a total eclipse of the Sun? If you did, would you be surprised to find someone else there already? In 2003, the Sun, the Moon, Antarctica, and two photographers all lined up in Antarctica during an unusual total solar eclipse. Even given the extreme location, a group of enthusiastic eclipse chasers ventured near the bottom of the world to experience the surreal momentary disappearance of the Sun behind the Moon. One of the treasures collected was the above picture -- a composite of four separate images digitally combined to realistically simulate how the adaptive human eye saw the eclipse. As the image was taken, both the Moon and the Sun peeked together over an Antarctic ridge. In the sudden darkness, the magnificent corona of the Sun became visible around the Moon. Quite by accident, another photographer was caught in one of the images checking his video camera. Visible to his left are an equipment bag and a collapsible chair. A total solar eclipse will occur on Friday and be visible from the north Atlantic Ocean.

Trifid Nebula Glows in Stunning Photo By Amateur Astronomer

Trifid Nebula Glows in Stunning Photo By Amateur Astronomer:  

by Nina Sen, Space.com Contributor

Date: 12 March 2015 Time: 08:19 AM ET

Trifid Nebula Unnikrishnan
Astrophotographer Navaneeth Unnikrishnan captured the Trifid Nebula from Karnataka, India.

CREDIT: Navaneeth Unnikrishnan


This stunning image of the Trifid Nebula was taken from Karnataka, India.

Astrophotographer Navaneeth Unnikrishnan captured the star factory using a DSLR camera and tracking mounted telescopes.

The Trifid Nebula (Messier 20 or NGC 6514) is a combination of emission nebula (the red area) and reflection nebula (the blue area) and dark nebula.  [What Do You See? Strange Nebula Shapes (Photos)]

The Trifid Nebula is located about 5,200 light-years from Earth. A light-year is the distance light travels in one year, or about 6 trillion miles (10 trillion kilometers). The Trifid takes its name from the dark dust bands that trisect its glowing heart. Astronomer Charles Messier first observed the Trifid Nebula in June 1764. Observations made about 60 years later revealed the dividing bands.

Unnikrishnan used a 11'' Schmidt Cassegrain Telescope, Canon 20D (Modified) with ISO 400 to combine 15 darks, 15 offset images.

To see more amazing night sky photos submitted by Space.com readers, visit our astrophotography archive.

Editor's note: If you have an amazing night sky photo you'd like to share for a possible story or image gallery, please contact managing editor Tariq Malik at spacephotos@space.com.



AWESOME Space Stories of the Week

Best Space Stories of the Week – March 15, 2015:


By Mike Wall, Senior Writer

Date: 15 March 2015 Time: 11:29 AM ET

Enceladus Cross-Section
Saturn's icy moon Enceladus is home to giant water geysers in the moon's south polar region. Scientists say interactions between hot water and rock on the floor of a subsurface ocean powers the hydrothermal reaction pushing gas and ice through Enceladus' 50-kilometer-thick (31 miles) ice crust.

CREDIT: NASA/JPL-Caltech


NASA launched a new space-weather mission, scientists found evidence of a hydrothermal system on Saturn's ocean-bearing moon Enceladus and three astronauts returned safely to Earth after nearly six months aboard the International Space Station. Here's a look at Space.com's top stories of the week:

NASA space weather mission takes flight

NASA launched its Magnetospheric Multiscale (MMS) mission, which consists of four satellites that will study energy eruptions in Earth’s magnetic field caused by space weather. MMS blasted off Thursday night (March 12) from Cape Canaveral, Florida, aboard a United Launch Alliance Atlas V rocket. [Full Story: Spectacular Night Launch Sends NASA Satellites on Hunt for Magnetic Collisions]

A hydrothermal system on Enceladus

Scientists have found evidence of active hydrothermal vents on Saturn's ice-covered moon Enceladus. Conditions deep in Enceladus' subsurface ocean may therefore be similar to those that gave rise to the first life on Earth. [Full Story: Hot Springs on Saturn's Moon Enceladus Powered by Hydrothermal Vents]

Spaceflyers come home

A Russian Soyuz spacecraft touched down on the steppes of Kazakhstan Wednesday night (March 11), wrapping up a nearly six-month stint aboard the International Space Station for NASA astronaut Barry "Butch" Wilmore and cosmonauts Alexander Samokutyaev and Elena Serova. [Full Story: US-Russian Space Crew Returns to Earth After 167 Days in Orbit]

Happy birthday, Kepler!

NASA's prolific Kepler space telescope, which has discovered more than half of all known planets beyond our solar system, just celebrated six years in space. The prolific planet hunter blasted off on March 6, 2009. [Full Story: Happy Birthday, Kepler! NASA Planet Hunter Marks 6 Years in Space]

NASA test-fires booster for Space Launch System megarocket

A giant rocket booster designed to help NASA’s next megarocket, the Space Launch System, soar into space roared to life in the Utah proving grounds of aerospace firm Orbital ATK on Wednesday (March 11). [Full Story: World's Largest Solid Rocket Booster Fired in Ground Test for NASA]

The first X-flare of 2015

The sun unleashed its first superpowerful flare of the year on Wednesday (March 11), and the intense eruption was aimed directly at Earth. The monster X-class solar flare, the strongest category of sun storms, caused an hour-long blackout in high-frequency radio communications over wide areas. [Full Story: Sun Unleashes 1st Monster Solar Flare of 2015 (Photos, Video)]

Pluto probe performs most-distant engine burn ever

NASA's New Horizons spacecraft, which will zoom through the Pluto system on July 14, fired its engines for 93 seconds on Tuesday (March 10), when it was about 3 billion miles (4.83 billion kilometers) from Earth. No spacecraft had ever conducted an engine burn at so great a distance from its handlers, mission officials said. [Full Story: NASA Probe Makes Record-Setting Engine Burn on Path to Pluto]

A subsurface ocean on Ganymede

A salty ocean lurks beneath the icy surface of Jupiter's largest moon, Ganymede, scientists using NASA's Hubble Space Telescope have found. Ganymede's ocean could actually harbor more water than all of Earth's surface water combined, according to NASA officials. [Full Story: Jupiter's Moon Ganymede Has a Salty Ocean with More Water than Earth]

Opportunity spies odd rocks near end of marathon trek

NASA's Opportunity Mars rover took a break in the home stretch of its Red Planet marathon to study some rocks the likes of which it's never seen before. As of March 5, the rover's odometer read 26.139 miles (42.067 kilometers), leaving it just 140 yards (128 meters) short of the marathon milestone. [Full Story: On Mars, Opportunity Rover Spots Weird Rocks Near Marathon Finish Line]

Lockheed Martin unveils ambitious new space transportation system

Aerospace firm Lockheed Martin has announced its plans for a new spaceflight system that could ferry cargo to the International Space Station, and also help get people to deep-space destinations such as the moon and Mars. [Full Story: Lockheed's 'Jupiter' Space Tug Could Fly to Space Station, Moon and Beyond]

What will NASA's Dawn probe look for at dwarf planet Ceres?

A Q&A with Chris Russell, principal investigator of NASA's Dawn mission, which recently arrived in orbit around the dwarf planet Ceres. [Full Story: Studying Dwarf Planet Ceres: Q&A with Dawn Scientist Chris Russell]

Follow Mike Wall on Twitter @michaeldwall and Google+. Follow us @Spacedotcom, Facebook or Google+.

Saturday, March 14, 2015

Inside the Eagle Nebula

Inside the Eagle Nebula: APOD: 2014 February 16 - Inside the Eagle Nebula


Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2014 February 16


See Explanation. Clicking on the picture will download the highest resolution version available.
Explanation: 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 gas remain 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 the Serpent (Serpens). This picture combines three specific emitted colors and was taken with the 0.9-meter telescope on Kitt Peak, Arizona, USA.

The Cosmic Web of the Tarantula Nebula

The Cosmic Web of the Tarantula Nebula: APOD: 2014 February 17 - The Cosmic Web of the Tarantula Nebula


Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2014 February 17


See Explanation. Clicking on the picture will download the highest resolution version available.
Explanation: It is the largest and most complex star forming region in the entire galactic neighborhood. Located in the Large Magellanic Cloud, a small satellite galaxy orbiting our Milky Way galaxy, the region's spidery appearance is responsible for its popular name, the Tarantula nebula. This tarantula, however, is about 1,000 light-years across. Were it placed at the distance of Milky Way's Orion Nebula, only 1,500 light-years distant and the nearest stellar nursery to Earth, it would appear to cover about 30 degrees (60 full moons) on the sky. Intriguing details of the nebula are visible in the above image shown in near true colors. The spindly arms of the Tarantula nebula surround NGC 2070, a star cluster that contains some of the brightest, most massive stars known, visible in blue in the image center. Since massive stars live fast and die young, it is not so surprising that the cosmic Tarantula also lies near the site of a close recent supernova.

Comet Lovejoy over The Great Wall

Comet Lovejoy over The Great Wall: APOD: 2014 February 20 - Comet Lovejoy over The Great Wall


Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2014 February 20


See Explanation. Clicking on the picture will download the highest resolution version available.
Explanation: Fading now as it returns to the outer solar system Comet Lovejoy (C/2013 R1) still graces planet Earth's sky, a delicate apparition in binoculars or small telescopes. The comet, a relic of the solar system's formative years, is seen here rising in the morning twilight on January 12 among the stars of Ophiuchus, the Serpent Bearer. Posing near the comet is bright star Alpha Ophiuchi, also known as Rasalhague, from Arabic "the head of the serpent collector". Of course, the serpentine shape below is the ancient Great Wall of China, along the Panlongshan section northeast of Beijing. Panlongshan is translated as "a coiled dragon". A moving and fortuitous scene, it was captured with a digital camera and telephoto lens in two consecutive exposures. The exposures were merged to show a natural looking foreground and twilight sky.

The Long Jet of the Lighthouse Nebula

The Long Jet of the Lighthouse Nebula: APOD: 2014 February 21 - The Long Jet of the Lighthouse Nebula


Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2014 February 21


See Explanation. Clicking on the picture will download the highest resolution version available.
Explanation: The Lighthouse nebula was formed by the wind of a pulsar, a rapidly rotating, magnetized neutron star, as it speeds through the interstellar medium at over 1,000 kilometers per second. Some 23,000 light-years distant toward the southern constellation Carina, pulsar and wind nebula (cataloged as IGR J1104-6103) are indicated at the lower right in this remarkable image from the Chandra X-ray Observatory. Energetic particles generated by the pulsar are swept back into the wind's comet-like tail trailing up and to the left, along the direction of the pulsar's motion away from its parent supernova remnant. Both runaway pulsar and expanding remnant debris field are the aftermath of the core-collapse-explosion of a massive star, with the pulsar kicked out by the supernova explosion. Adding to the scene of exotic cosmic extremes is a long, spiraling jet extending for almost 37 light-years, but nearly at a right angle to the pulsar's motion. The high-energy particle jet is the longest known for any object in our Milky Way galaxy.

M44: The Beehive Cluster

M44: The Beehive Cluster: APOD: 2014 February 22 - M44: The Beehive Cluster


Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2014 February 22


See Explanation. Clicking on the picture will download the highest resolution version available.
Explanation: A mere 600 light-years away, M44 is one of the closest star clusters to our solar system. Also known as the Praesepe or the Beehive cluster its stars are young though, about 600 million years old compared to our Sun's 4.5 billion years. Based on similar ages and motion through space, M44 and the even closer Hyades star cluster in Taurus are thought to have been born together in the same large molecular cloud. An open cluster spanning some 15 light-years, M44 holds 1,000 stars or so and covers about 3 full moons (1.5 degrees) on the sky in the constellation Cancer. Visible to the unaided eye, M44 has been recognized since antiquity. Described as a faint cloud or celestial mist long before being included as the 44th entry in Charles Messier's 18th century catalog, the cluster was not resolved into its individual stars until telescopes were available. A popular target for modern, binocular-equiped sky gazers, the cluster's few yellowish tinted, cool, red giants are scattered through the field of its brighter hot blue main sequence stars in this colorful stellar group snapshot.

Cassini Spacecraft Crosses Saturns Ring Plane

Cassini Spacecraft Crosses Saturns Ring Plane: APOD: 2014 February 23 - Cassini Spacecraft Crosses Saturns Ring Plane


Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2014 February 23


See Explanation. Clicking on the picture will download the highest resolution version available.
Explanation: If this is Saturn, where are the rings? When Saturn's "appendages" disappeared in 1612, Galileo did not understand why. Later that century, it became understood that Saturn's unusual protrusions were rings and that when the Earth crosses the ring plane, the edge-on rings will appear to disappear. This is because Saturn's rings are confined to a plane many times thinner, in proportion, than a razor blade. In modern times, the robot Cassini spacecraft orbiting Saturn now also crosses Saturn's ring plane. A series of plane crossing images from 2005 February was dug out of the vast online Cassini raw image archive by interested Spanish amateur Fernando Garcia Navarro. Pictured above, digitally cropped and set in representative colors, is the striking result. Saturn's thin ring plane appears in blue, bands and clouds in Saturn's upper atmosphere appear in gold. Details of Saturn's rings can be seen in the high dark shadows across the top of this image, taken back in 2005. Moons appear as bumps in the rings.

The Pleiades Deep and Dusty

The Pleiades Deep and Dusty: APOD: 2014 February 25 - The Pleiades Deep and Dusty


Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2014 February 25


See Explanation. Clicking on the picture will download the highest resolution version available.
The Pleiades Deep and Dusty

Image Credit & Copyright: David Lane
Explanation: The well known Pleiades star cluster is slowly destroying part of a passing cloud of gas and dust. The Pleiades is the brightest open cluster of stars on Earth's sky and can be seen from almost any northerly location with the unaided eye. The passing young dust cloud is thought to be part of Gould's belt, an unusual ring of young star formation surrounding the Sun in the local Milky Way Galaxy. Over the past 100,000 years, part of Gould's belt is by chance moving right through the older Pleiades and is causing a strong reaction between stars and dust. Pressure from the stars' light significantly repels the dust in the surrounding blue reflection nebula, with smaller dust particles being repelled more strongly. A short-term result is that parts of the dust cloud have become filamentary and stratified, as seen in the above deep-exposure image.

Aurora over New Zealand

Aurora over New Zealand: APOD: 2014 February 26 - Aurora over New Zealand


Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2014 February 26


See Explanation. Clicking on the picture will download the highest resolution version available.
Explanation: Sometimes the more you look at an image, the more you see. Such may be the case for this beautiful nighttime panorama taken last week in New Zealand. Visible right off, on the far left, are common clouds, slightly altered by the digital fusion of combining 11 separate 20-second exposures. More striking, perhaps, is the broad pink aurora that dominates the right part of the image, a less common auroral color that is likely tinted by excited oxygen atoms high in Earth's atmosphere. Keep looking and you might notice a bright light just beyond the mountain on the left. That is the rising Moon -- and an even closer look will reveal faint crepuscular rays emanating from it. Musing over the image center may cause you to notice the central band of the Milky Way Galaxy which here appears to divide, almost vertically, the left clouds from the right aurora. Inspecting the upper right of the image reveals a fuzzy patch, high in the sky, that is the Small Magellanic Cloud. Numerous stars discretely populate the distant background. Back on Earth, the image foreground features two domes of the Mt. John University Observatory and a camera tripod looking to capture much of this scene over a serene Lake Tekapo.

Daytime Moon Meets Morning Star

Daytime Moon Meets Morning Star: APOD: 2014 February 27 - Daytime Moon Meets Morning Star


Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2014 February 27


See Explanation. Clicking on the picture will download the highest resolution version available.
Explanation: Venus now appears as planet Earth's brilliant morning star standing above the eastern horizon before dawn. For most, the silvery celestial beacon rose in a close pairing with an old crescent Moon on February 26. But seen from locations in western Africa before sunrise, the lunar crescent actually occulted or passed in front of Venus, also in a crescent phase. Farther to the east, the occultation occurred during daylight hours. In fact, this telescopic snapshot of the dueling crescents was captured just before the occultation began under an afternoon's crystal clear skies from Yunnan Province, China. The unforgettable scene was easily visible to the naked eye in broad daylight.

Mobius Arch Moonrise

Mobius Arch Moonrise: APOD: 2014 February 28 - Mobius Arch Moonrise


Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2014 February 28


See Explanation. Clicking on the picture will download the highest resolution version available.
Explanation: Only two days past full, February's moon shines through thin clouds, rising on the left in this fisheye night skyscape. The moonlight illuminates a weathered, rounded foreground in the Alabama Hills, conveniently located east of Mt. Whitney along the Sierra Nevada range in California, USA, planet Earth. Orion the Hunter stands at the right, a familiar northern winter constellation. Bright Jupiter, the solar system's ruling gas giant, is near center at the top of the frame. Below Jupiter, Sirius, alpha star of the Big Dog, poses above a bowed and twisted landform known as Möbius Arch, its curve reminiscent of the mathematically famous surface with only one side. Of course, instead of using rock, wind, and weather, a Möbius strip is easier to make with paper, scissors, and tape.

NGC 7331 and Beyond

NGC 7331 and Beyond: APOD: 2014 March 1 - NGC 7331 and Beyond


Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2014 March 1


See Explanation. Clicking on the picture will download the highest resolution version available.
Explanation: Big, beautiful spiral galaxy NGC 7331 is often touted as an analog to our own Milky Way. About 50 million light-years distant in the northern constellation Pegasus, NGC 7331 was recognized early on as a spiral nebula and is actually one of the brighter galaxies not included in Charles Messier's famous 18th century catalog. Since the galaxy's disk is inclined to our line-of-sight, long telescopic exposures often result in an image that evokes a strong sense of depth. The effect is further enhanced in this sharp image by galaxies that lie beyond the gorgeous island universe. The background galaxies are about one tenth the apparent size of NGC 7331 and so lie roughly ten times farther away. Their close alignment on the sky with NGC 7331 occurs just by chance. Seen here through faint foreground dust clouds lingering above the plane of Milky Way, this visual grouping of galaxies is also known as the Deer Lick Group.

Martian Sunset

Martian Sunset: APOD: 2014 March 2 - Martian Sunset


Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2014 March 2


See Explanation. Clicking on the picture will download the highest resolution version available.
Explanation: What would it be like to see a sunset on Mars? To help find out, the robotic rover Spirit was deployed in 2005 to park and watch the Sun dip serenely below the distant lip of Gusev crater. Colors in the above image have been slightly exaggerated but would likely be apparent to a human explorer's eye. Fine martian dust particles suspended in the thin atmosphere lend the sky a reddish color, but the dust also scatters blue light in the forward direction, creating a bluish sky glow near the setting Sun. Because Mars is farther away, the Sun is less bright and only about two thirds the diameter it appears from Earth. Images like this help atmospheric scientists understand not only the atmosphere of Mars, but atmospheres across the Solar System, including our home Earth.

Habitable Worlds

Habitable Worlds: APOD: 2014 March 3 - Habitable Worlds


Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2014 March 3


See Explanation. Clicking on the picture will download the highest resolution version available.
Explanation: Is Earth the only known world that can support life? In an effort to find life-habitable worlds outside our Solar System, stars similar to our Sun are being monitored for slight light decreases that indicate eclipsing planets. Many previously-unknown planets are being found, including over 700 worlds recently uncovered by NASA's Kepler satellite. Depicted above in artist's illustrations are twelve extrasolar planets that orbit in the habitable zones of their parent stars. These exoplanets have the right temperature for water to be a liquid on their surfaces, and so water-based life on Earth might be able to survive on them. Although technology cannot yet detect resident life, finding habitable exoplanets is a step that helps humanity to better understand its place in the cosmos.

Globules in the Running Chicken Nebula

Globules in the Running Chicken Nebula: APOD: 2014 March 5 - Globules in the Running Chicken Nebula


Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2014 March 5


See Explanation. Clicking on the picture will download the highest resolution version available.
Globules in the Running Chicken Nebula

Image Credit & Copyright: Fred Vanderhaven
Explanation: The eggs from this chicken may form into stars. The above pictured emission nebula, cataloged as IC 2944, is called the Running Chicken Nebula for the shape of its greater appearance. The image was taken recently from Siding Spring Observatory in Australia and presented in scientifically assigned colors. Seen near the center of the image are small, dark molecular clouds rich in obscuring cosmic dust. Called Thackeray's Globules for their discoverer, these "eggs" are potential sites for the gravitational condensation of new stars, although their fates are uncertain as they are also being rapidly eroded away by the intense radiation from nearby young stars. Together with patchy glowing gas and complex regions of reflecting dust, these massive and energetic stars form the open cluster Collinder 249. This gorgeous skyscape spans about 70 light-years at the nebula's estimated 6,000 light-year distance.

NGC 1333 Stardust

NGC 1333 Stardust: APOD: 2014 March 6 - NGC 1333 Stardust


Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2014 March 6
See Explanation. Clicking on the picture will download the highest resolution version available.
Explanation: NGC 1333 is seen in visible light as a reflection nebula, dominated by bluish hues characteristic of starlight reflected by dust. A mere 1,000 light-years distant toward the heroic constellation Perseus, it lies at the edge of a large, star-forming molecular cloud. This striking close-up view spans about two full moons on the sky or just over 15 light-years at the estimated distance of NGC 1333. It shows details of the dusty region along with hints of contrasting red emission from Herbig-Haro objects, jets and shocked glowing gas emanating from recently formed stars. In fact, NGC 1333 contains hundreds of stars less than a million years old, most still hidden from optical telescopes by the pervasive stardust. The chaotic environment may be similar to one in which our own Sun formed over 4.5 billion years ago.

A View from the Zone

A View from the Zone: APOD: 2014 March 7 - A View from the Zone


Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2014 March 7


See Explanation. Clicking on the picture will download the highest resolution version available.
Explanation: Brilliant Venus and the central Milky Way rise in the early morning hours of March 1 in this sea and skyscape. The scene looks out from a beach at Sea Isle City, New Jersey, USA, planet Earth. Of course, Earth orbits well within the solar system's habitable zone, that Goldilocks region not too close and not too far from the Sun where surface temperatures can support liquid water. Similar in size to Earth, Venus lies just beyond the inner boundary of the habitable zone. The watery reflection of light from our inhospitable sister planet is seen along a calm, cold ocean and low cloud bank.

A Hole in Mars

A Hole in Mars: APOD: 2014 March 9 - A Hole in Mars


Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2014 March 9


See Explanation. Clicking on the picture will download the highest resolution version available.
Explanation: What created this unusual hole in Mars? The hole was discovered by chance in 2011 on images of the dusty slopes of Mars' Pavonis Mons volcano taken by the HiRISE instrument aboard the robotic Mars Reconnaissance Orbiter currently circling Mars. The hole appears to be an opening to an underground cavern, partly illuminated on the image right. Analysis of this and follow-up images revealed the opening to be about 35 meters across, while the interior shadow angle indicates that the underlying cavern is roughly 20 meters deep. Why there is a circular crater surrounding this hole remains a topic of speculation, as is the full extent of the underlying cavern. Holes such as this are of particular interest because their interior caves are relatively protected from the harsh surface of Mars, making them relatively good candidates to contain Martian life. These pits are therefore prime targets for possible future spacecraft, robots, and even human interplanetary explorers.

Gamma Rays from Galactic Center Dark Matter

Gamma Rays from Galactic Center Dark Matter:

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2014 March 10


See Explanation. Clicking on the picture will download the highest resolution version available.
Explanation: What is creating the gamma rays at the center of our Galaxy? Excitement is building that one answer is elusive dark matter. Over the past few years the orbiting Fermi Gamma-ray Space Telescope has been imaging our Galaxy's center in gamma-rays. Repeated detailed analyses indicate that the region surrounding the Galactic center seems too bright to be accounted by known gamma-ray sources. A raw image of the Galactic Center region in gamma-rays is shown above on the left, while the image on the right has all known sources subtracted -- leaving an unexpected excess. An exciting hypothetical model that seems to fit the excess involves a type of dark matter known as WIMPs, which may be colliding with themselves to create the detected gamma-rays. This hypothesis is controversial, however, and debate and more detailed investigations are ongoing. Finding the nature of dark matter is one of the great quests of modern science, as previously this unusual type of cosmologically pervasive matter has shown itself only through gravitation.

In the Heart of the Rosette Nebula

In the Heart of the Rosette Nebula: APOD: 2014 March 11 - In the Heart of the Rosette Nebula


Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2014 March 11


See Explanation. Clicking on the picture will download the highest resolution version available.
Explanation: 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. The above image taken in January 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).

Messier 63: The Sunflower Galaxy

Messier 63: The Sunflower Galaxy: APOD: 2014 March 13 - Messier 63: The Sunflower Galaxy


Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2014 March 13
See Explanation. Clicking on the picture will download the highest resolution version available.
Explanation: A bright spiral galaxy of the northern sky, Messier 63 is about 25 million light-years distant in the loyal constellation Canes Venatici. Also cataloged as NGC 5055, the majestic island universe is nearly 100,000 light-years across. That's about the size of our own Milky Way Galaxy. Known by the popular moniker, The Sunflower Galaxy, M63 sports a bright yellowish core in this sharp, colorful galaxy portrait. Its sweeping blue spiral arms are streaked with cosmic dust lanes and dotted with pink star forming regions. A dominant member of a known galaxy group, M63 has faint, extended features that could be the result of gravitational interactions with nearby galaxies. In fact, M63 shines across the electromagnetic spectrum and is thought to have undergone bursts of intense star formation.

Polar Ring Galaxy NGC 2685

Polar Ring Galaxy NGC 2685: APOD: 2014 March 14 - Polar Ring Galaxy NGC 2685


Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2014 March 14
See Explanation. Clicking on the picture will download the highest resolution version available.
Explanation: NGC 2685 is a confirmed polar ring galaxy - a rare type of galaxy with stars, gas and dust orbiting in rings perpendicular to the plane of a flat galactic disk. The bizarre configuration could be caused by the chance capture of material from another galaxy by a disk galaxy, with the captured debris strung out in a rotating ring. Still, observed properties of NGC 2685 suggest that the rotating ring structure is remarkably old and stable. In this sharp view of the peculiar system also known as Arp 336 or the Helix galaxy, the strange, perpendicular rings are easy to trace as they pass in front of the galactic disk, along with other disturbed outer structures. NGC 2685 is about 50,000 light-years across and 40 million light-years away in the constellation Ursa Major.