Tag: Astronomy Picture of the Day

Astronomy Picture of the Day – LDN 988 and Friends

Astronomy Picture of the Day

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 September 24

  LDN 988 and Friends
Image Credit & Copyright: Rafael Rodríguez Morales

 

 

Explanation: Stars are forming in dark, dusty molecular cloud LDN 988. Seen near picture center some 2,000 light-years distant, LDN 988 and other nearby dark nebulae were cataloged by Beverly T. Lynds in 1962 using Palomar Observatory Sky Survey plates. Narrowband and near-infrared explorations of the dark nebula reveal energetic shocks and outflows light-years across associated with dozens of newborn stars. But in this sharp optical telescopic view, the irregular outlines of LDN 988 and friends look like dancing stick figures eclipsing the rich starfields of the constellation Cygnus. From dark sites the region can be identified by eye alone. It’s part of the Great Rift of dark clouds along the plane of the Milky Way galaxy known as the Northern Coalsack.

Astronomy Picture of the Day – Pickering’s Triangle in the Veil

Astronomy Picture of the Day

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 September 17

Pickering’s Triangle in the Veil
Image Credit & Copyright: J-P Metsävainio (Astro Anarchy)

 

Explanation: Chaotic in appearance, these filaments of shocked, glowing gas break across planet Earth’s sky toward the constellation of Cygnus, as 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 waves plow 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 the glow of ionized hydrogen and sulfur atoms shown in red and green, and oxygen in blue hues. 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 field of view spans less than one third that distance. Identified as Pickering’s Triangle for a director of Harvard College Observatory and cataloged as NGC 6979, the complex of filaments might be more appropriately known as Williamina Fleming’s Triangular Wisp.

Astronomy Picture of the Day – Pluto from above Cthulhu Regio

Astronomy Picture of the Day

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 September 14

Pluto from above Cthulhu Regio
Image Credit: NASA, Johns Hopkins Univ./APL, Southwest Research Inst.

 

Explanation: New high resolution images of Pluto are starting to arrive from the outer Solar System. The robotic New Horizons spacecraft, which zoomed by Pluto in July, has finished sending back some needed engineering data and is now transmitting selections from its tremendous storehouse of images of Pluto and its moons. The featured image, a digital composite, details a surprising terrain filled with craters, plains, landscape of unknown character, and landforms that resemble something on Earth but are quite unexpected on Pluto. The light area sprawling across the upper right has been dubbed Sputnik Planum and is being studied for its unusual smoothness, while the dark cratered area just under the spacecraft is known as Cthulhu Regio. So far, New Horizons has only shared a few percent of the images and data it took during its Pluto flyby, but will continue to send back new views of the dwarf planet even as it glides outward toward even more distant explorations.

Astronomy Picture of the Day – Earthrise

Astronomy Picture of the Day

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 September 6

Earthrise
Image Credit: Apollo 8, NASA

Explanation: What’s that rising over the edge of the Moon? Earth. About 47 years ago, in December of 1968, the Apollo 8 crew flew from the Earth to the Moon and back again. Frank Borman, James Lovell, and William Anders were launched atop a Saturn V rocket on December 21, circled the Moon ten times in their command module, and returned to Earth on December 27. The Apollo 8 mission’s impressive list of firsts includes: the first humans to journey to the Earth’s Moon, the first to fly using the Saturn V rocket, and the first to photograph the Earth from deep space. As the Apollo 8 command module rounded the farside of the Moon, the crew could look toward the lunar horizon and see the Earth appear to rise, due to their spacecraft’s orbital motion. Their famous picture of a distant blue Earth above the Moon’s limb was a marvelous gift to the world.

Astronomy Picture of the Day – Milky Way with Airglow Australis

Astronomy Picture of the Day

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 September 4

Milky Way with Airglow Australis
Image Credit & Copyright: Yuri Beletsky (Carnegie Las Campanas Observatory)

 

Explanation: After sunset on September 1, an exceptionally intense, reddish airglow flooded this Chilean winter night skyscape. Above a sea of clouds and flanking the celestial Milky Way, the airglow seems to ripple and flow across the northern horizon in atmospheric waves. Originating at an altitude similar to aurorae, the luminous airglow is instead due to chemiluminescence, the production of light through chemical excitation. Commonly captured with a greenish tinge by sensitive digital cameras, this reddish airglow emission is from OH molecules and oxygen atoms at extremely low densities and has often been present in southern hemisphere nights during the last few years. On this night it was visible to the eye, but seen without color. Antares and the central Milky Way lie near the top, with bright star Arcturus at left. Straddling the Milky Way close to the horizon are Vega, Deneb, and Altair, known in northern nights as the stars of the Summer Triangle.

Astronomy Picture of the Day – The Flare and the Galaxy

Astronomy Picture of the Day

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 September 2


The Flare and the Galaxy
Image Credit & Copyright: Martin Mark

 

Explanation: Is this person throwing a lightning bolt? No. Despite appearances, this person is actually pointing in the direction of a bright Iridium flare, a momentary reflection of sunlight off of a communications satellite in orbit around the Earth. As the Iridium satellite orbits, reflective antennas became aligned between the observer and the Sun to create a flash brighter than any star in the night sky. Iridium flares typically last several seconds, longer than most meteors. Also unlike meteors, the flares are symmetric and predictable. The featured flare involved Iridium satellite 15 and occurred over southern Estonia last week. In this well-planned image, a spectacular night sky appears in the background, complete with the central band of our Milky Way Galaxy running vertically up the image center.

Astronomy Picture of the Day – Pluto in Enhanced Color

Astronomy Picture of the Day

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 August 31

Pluto in Enhanced Color
Image Credit: NASA, Johns Hopkins Univ./APL, Southwest Research Inst.

 

Explanation: Pluto is more colorful than we can see. Color data and images of our Solar System’s most famous dwarf planet, taken by the robotic New Horizons spacecraft during its flyby in July, have been digitally combined to give an enhanced view of this ancient world sporting an unexpectedly young surface. The featured enhanced color image is not only esthetically pretty but scientifically useful, making surface regions of differing chemical composition visually distinct. For example, the light-colored heart-shaped Tombaugh Regio on the lower right is clearly shown here to be divisible into two regions that are geologically different, with the leftmost lobe Sputnik Planum also appearing unusually smooth. New Horizons now continues on beyond Pluto, will continue to beam back more images and data, and will soon be directed to change course so that it can fly past asteroid 2014 MU69 in 2019 January.

Astronomy Picture of the Day –

Astronomy Picture of the Day

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 August 28

Puppis A Supernova Remnant
Image Credit & Copyright: Don Goldman

 

Explanation: Driven by the explosion of a massive star, supernova remnant Puppis A is blasting into the surrounding interstellar medium about 7,000 light-years away. At that distance, this colorful telescopic field based on broadband and narrowband optical image data is about 60 light-years across. As the supernova remnant expands into its clumpy, non-uniform surroundings, shocked filaments of oxygen atoms glow in green-blue hues. Hydrogen and nitrogen are in red. Light from the initial supernova itself, triggered by the collapse of the massive star’s core, would have reached Earth about 3,700 years ago. The Puppis A remnant is actually seen through outlying emission from the closer but more ancient Vela supernova remnant, near the crowded plane of our Milky Way galaxy. Still glowing across the electromagnetic spectrum Puppis A remains one of the brightest sources in the X-ray sky.

Astronomy Picture of the Day – The Large Cloud of Magellan

Astronomy Picture of the Day

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 August 27

 

The Large Cloud of Magellan
Image Credit & Copyright: Carlos Fairbairn

 

Explanation: The 16th century Portuguese navigator Ferdinand Magellan and his crew had plenty of time to study the southern sky during the first circumnavigation of planet Earth. As a result, two fuzzy cloud-like objects easily visible to southern hemisphere skygazers are known as the Clouds of Magellan, now understood to be satellite galaxies of our much larger, spiral Milky Way galaxy. About 160,000 light-years distant in the constellation Dorado, the Large Magellanic Cloud (LMC) is seen here in a remarkably deep, colorful, image. Spanning about 15,000 light-years or so, it is the most massive of the Milky Way’s satellite galaxies and is the home of the closest supernova in modern times, SN 1987A. The prominent patch below center is 30 Doradus, also known as the magnificent Tarantula Nebula, is a giant star-forming region about 1,000 light-years across.

Astronomy Picture of the Day – Comet Dust over Enchanted Rock

Astronomy Picture of the Day

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 August 14

 

 Comet Dust over Enchanted Rock
Image Credit & Copyright: Jared Tennant

 

Explanation: Dusty debris from periodic Comet Swift-Tuttle was swept up by planet Earth this week. Vaporized by their passage through the dense atmosphere at 59 kilometers per second, the tiny grains produced a stream of Perseid meteors. A bright, colorful Perseid meteor flash was captured during this 20 second exposure. It made its ephemeral appearance after midnight on August 12, in the moonless skies over the broad granite dome of Enchanted Rock State Natural Area, central Texas, USA. Below the Perseid meteor, trees stand in silhouette against scattered lights along the horizon and the faint Milky Way, itself cut by dark clouds of interstellar dust.

Astronomy Picture of the Day – Aurora in the Backyard

Astronomy Picture of the Day

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 August 4

Aurora in the Backyard
Image Credit & Copyright: P-M Hedén (Clear Skies, TWAN)

 

Explanation: On the night of March 17/18 this umbrella of northern lights unfolded over backyards in Vallentuna, Sweden about 30 kilometers north of Stockholm. A result of the strongest geomagnetic storm of this solar cycle, auroral displays were captured on that night from back and front yards at even lower latitudes, including sightings in the midwestern United States. A boon for aurora hunting skywatchers, the space storm began building when a coronal mass ejection, launched by solar activity some two days earlier, struck planet Earth’s magnetosphere. So what’s the name of the backyard observatory on the right of the wide field view? That’s Carpe Noctem Observatory, of course.

Astronomy Picture of the Day – A Proton Arc Over Lake Superior

Astronomy Picture of the Day

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 August 3

 

A Proton Arc Over Lake Superior
Image Credit & Copyright: Ken Williams

Explanation: The setting had been picked out — all that was needed was an aurora. And late last August, forecasts predicted that an otherwise beautiful night sky would be lit up with auroral green. Jumping into his truck, the astrophotographer approached his secret site — but only after a five hour drive across the rural Upper Peninsula of Michigan. What he didn’t know was that his luck was just beginning. While setting up for the image, a proton arc — a rare type of aurora — appeared. The red arc lasted only about 15 minutes, but that was long enough to capture in a 30-second exposure. As the name indicates, proton arcs are caused not by electrons but by more massive protons that bombard the Earth’s atmosphere following an energetic event on the Sun. In the featured image, the yellow lights on the horizon are the city lights of Marquette, Michigan, USA. The blue and yellow rocks in the Lake Superior foreground are lit by a LED flashlight. Also captured, to the left of the red proton arc, was the band of our Milky Way Galaxy.

Astronomy Picture of the Day – Sentinels of the Arctic

Astronomy Picture of the Day

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.

Sentinels of the Arctic
Image Credit & Copyright: Niccolò Bonfadini

 

Explanation: Who guards the north? Judging from the above photograph, possibly giant trees covered in snow and ice. The featured picture was taken a few winters ago in Finnish Lapland where weather can include sub-freezing temperatures and driving snow. Surreal landscapes sometimes result, where common trees become cloaked in white and so appear, to some, as watchful aliens. Far in the distance, behind this uncommon Earthly vista, is a more common sight — a Belt of Venus that divided a darkened from sunlit sky as the Sun rose behind the photographer. Of course, in the spring, the trees thaw and Lapland looks much different.

Astronomy Picture of the Day – Pluto Resolved

Astronomy Picture of the Day

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 July 15

Pluto Resolved
Image Credit & Copyright: NASA, Johns Hopkins Univ./APL, Southwest Research Inst.

 

Explanation: New Horizons has survived its close encounter with Pluto and has resumed sending back images and data. The robotic spacecraft reported back on time, with all systems working, and with the expected volume of data stored. Featured here is the highest resolution image of Pluto taken before closest approach, an image that really brings Pluto into a satisfying focus. At first glance, Pluto is reddish and has several craters. Toward the image bottom is a surprisingly featureless light-covered region that resembles an iconic heart, and mountainous terrain appears on the lower right. This image, however, is only the beginning. As more images and data pour in today, during the coming week, and over the next year, humanity’s understanding of Pluto and its moons will likely become revolutionized.

Astronomy Picture of the Day

Astronomy Picture of the Day

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 July 7

 The Milky Way from a Malibu Sea Cave
Image Credit & Copyright: Jack Fusco

 
Explanation: What’s happening outside this cave? Nothing unexpected – it’s just the central band of our Milky Way Galaxy passing by. As the Earth turns, the band of our Galaxy appears to rotate and shift along the horizon. The featured image was taken by a photographer who professes a passion for locating sea caves, and who found this spectacular grotto in Leo Carrillo State Park near Malibu, California, USA. After some planning, he timed this single shot image through the 10-meter high cave entrance to show the Milky Way far in the distance. In the foreground, several rocks about one meter across are visible. Visible in the background starscape are millions of stars including the relatively bright and orange Antares, situated just to the right of the image center.

Astronomy Picture of the Day – Colorful Clouds Near Rho Ophiuchi

Astronomy Picture of the Day

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 July 6

Colorful Clouds Near Rho Ophiuchi
Image Credit & Copyright: Markus Noller (Deep-Sky-Images)

 

Explanation: Why is the sky near Antares and Rho Ophiuchi so colorful? The colors result from a mixture of objects and processes. Fine dust illuminated from the front by starlight produces blue reflection nebulae. Gaseous clouds whose atoms are excited by ultraviolet starlight produce reddish emission nebulae. Backlit dust clouds block starlight and so appear dark. Antares, a red supergiant and one of the brighter stars in the night sky, lights up the yellow-red clouds on the lower center of the featured image. Rho Ophiuchi lies at the center of the blue nebula on the left. The distant globular cluster M4 is visible to the upper right of center. These star clouds are even more colorful than humans can see, emitting light across the electromagnetic spectrum.

Astronomy Picture of the Day – Crystals on Mars

Astronomy Picture of the Day

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 July 3

Crystals on Mars
Image Credit: NASA, JPL-Caltech, MSSS Explanation: This extreme close-up, a mosaic from the Mars Hand Lens Imager (MAHLI) on the Curiosity rover, spans a breathtaking 5 centimeters. It captures what appear to be elongated crystal shapes formed by the precipitation of minerals dissolved in water, a likely result of the evaporation of ancient lake or river from the Martian surface. Brushed by a dust removal tool and illuminated by white LEDs, the target rock named Mojave was found on the Pink Cliffs outcrop of the Pahrump Hills at the base of Mount Sharp. The MAHLI images were acquired on Curiosity’s sol 809, known on planet Earth as November 15, 2014. Of course, the inset 1909 Lincoln Cent image is provided for a comparison scale. Covered with Mars dust itself, the penny is a MAHLI calibration target attached to the rover.

Astronomy Picture of the Day – An Unusual Mountain on Asteroid Ceres

Astronomy Picture of the Day

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 June 30

An Unusual Mountain on Asteroid Ceres
Image Credit: NASA, JPL-Caltech, UCLA, MPS/DLR/IDA

 

Explanation: What created this large mountain on asteroid Ceres? No one is yet sure. As if in anticipation of today being Asteroid Day on Earth, the robotic spacecraft Dawn in orbit around Ceres took the best yet image of an unusually tall mountain on the Asteroid Belt’s largest asteroid. Visible at the top of the featured image, the exceptional mountain rises about five kilometers up from an area that otherwise appears pretty level. The image was taken about two weeks ago from about 4,400 kilometers away. Although origin hypotheses for the mountain include volcanism, impacts, and plate tectonics, clear evidence backing any of these is currently lacking. Also visible across Ceres’ surface are some enigmatic light areas: bright spots whose origin and composition that also remain an active topic of investigation. Even though Dawn is expected to continue to orbit Ceres, officially dubbed a dwarf planet, for millions of years, the hydrazine fuel used to point Dawn’s communications antenna toward Earth is expected to run out sometime next year.

Astronomy Picture of the Day – Star Trails above Table Mountain

Astronomy Picture of the Day

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 June 25

Star Trails above Table Mountain
Image Credit & Copyright:Eric Nathan

 

 

Explanation: Stars trail above and urban lights sprawl below in this moonlit nightscape from Cape Town, South Africa, planet Earth. The looming form of Table Mountain almost seems to hold terrestrial lights at bay while the stars circle the planet’s South Celestial Pole. This modern perspective on the natural night sky was captured in June 2014, the scene composed of over nine hundred, stacked 30 second exposures. The stunning result was chosen as the winner in the Against the Lights category, a selection from over 800 entries in The World at Night’s 2015 International Earth and Sky Photo Contest.

Astronomy Picture of the Day – Triple Conjunction Over Galician National Park

Astronomy Picture of the Day

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 June 24

Triple Conjunction Over Galician National Park
Image Credit & Copyright: Fernando Rey (LuzLux)

 

Explanation: What are those bright objects hovering over the horizon? Planets — and the Moon. First out, the horizon featured is a shoreline of the Atlantic Ocean that occurs at the Galicia National Park in northern Spain. Next furthest out, on the left, is the Moon. Easily the brightest object on the night sky, the Moon here was in only a crescent phase. The next furthest out, on the right, is the planet Venus, while planet Jupiter is seen at the top of the triangle. The long exposure from our rapidly rotating Earth made all of celestial objects — including the far distant stars — appear as slight arcs. The featured image was taken last Sunday night. Although the Moon’s orbit has now taken it away from this part of the sky, the planets Venus and Jupiter can be seen superposed just after sunset until mid-August. The closest apparent separation of Venus and Jupiter will occur in one week, when the two planets will appear separated by less than the angular diameter of the Moon.