An alluring sight in southern skies, the Large Magellanic Cloud (LMC) is seen in this deep and detailed telescopic mosaic. Recorded with broadband and narrowband filters, the scene spans some 5 degrees or 10 full moons. The narrowband filters are designed to transmit only light emitted by hydrogen, and oxygen atoms. Ionized by energetic starlight, the atoms emit their characteristic light as electrons are recaptured and the atoms transition to a lower energy state. As a result, in this image the LMC seems covered with its own clouds of ionized gas surrounding its massive, young stars. Sculpted by the strong stellar winds and ultraviolet radiation, the glowing clouds, dominated by emission from hydrogen, are known as H II (ionized hydrogen) regions. Itself composed of many overlapping H II regions, the Tarantula Nebula is the large star forming region at the left. The largest satellite of our Milky Way Galaxy, the LMC is about 15,000 light-years across and lies a mere 160,000 light-years away toward the constellation Dorado. via NASA
Thursday, January 18, 2018
Wikipedia picture of the day on January 19, 2018: Scots Pine (Pinus sylvestris), east part of Utö, Haninge Municipality, Stockholm archipelago, Sweden. In the background the Baltic Sea, with some sea smoke. Wikipedia"
Wednesday, January 17, 2018
Wikipedia picture of the day on January 18, 2018: Young European bison (Bison bonasus) in the Wisentgehege Springe game park near Springe, Hanover, Germany. The European bison or wisent is the heaviest of the surviving land animals in Europe, with males growing to around 1,000 kg (2,200 lb). European bison were hunted to extinction in the wild, but have since been reintroduced from captivity into several countries. Wikipedia"
This exciting and unfamiliar view of the Orion Nebula is a visualization based on astronomical data and movie rendering techniques. Up close and personal with a famous stellar nursery normally seen from 1,500 light-years away, the digitally modeled frame transitions from a visible light representation based on Hubble data on the left to infrared data from the Spitzer Space Telescope on the right. The perspective at the center looks along a valley over a light-year wide, in the wall of the region's giant molecular cloud. Orion's valley ends in a cavity carved by the energetic winds and radiation of the massive central stars of the Trapezium star cluster. The single frame is part of a multiwavelength, three-dimensional video that lets the viewer experience an immersive, three minute flight through the Great Nebula of Orion. via NASA
Tuesday, January 16, 2018
With image data from telescopes large and small, this close-up features the dusty Elephant's Trunk Nebula. It winds through the emission nebula and young star cluster complex IC 1396, in the high and far off constellation of Cepheus. Also known as vdB 142, the cosmic elephant's trunk is over 20 light-years long. The colorful view highlights bright, swept-back ridges that outline the region's pockets of cool interstellar dust and gas. Such embedded, dark, tendril-shaped clouds contain the raw material for star formation and hide protostars within. Nearly 3,000 light-years distant, the relatively faint IC 1396 complex covers a large region on the sky, spanning over 5 degrees. This dramatic scene spans a 1 degree wide field, about the size of 2 Full Moons. via NASA
Monday, January 15, 2018
Sunday, January 14, 2018
By starlight this eerie visage shines in the dark, a crooked profile evoking its popular name, the Witch Head Nebula. In fact, this entrancing telescopic portrait gives the impression that the witch has fixed her gaze on Orion's bright supergiant star Rigel. More formally known as IC 2118, the Witch Head Nebula spans about 50 light-years and is composed of interstellar dust grains reflecting Rigel's starlight. The blue color of the Witch Head Nebula and of the dust surrounding Rigel is caused not only by Rigel's intense blue starlight but because the dust grains scatter blue light more efficiently than red. The same physical process causes Earth's daytime sky to appear blue, although the scatterers in Earth's atmosphere are molecules of nitrogen and oxygen. Rigel, the Witch Head Nebula, and gas and dust that surrounds them lie about 800 light-years away. via NASA
Saturday, January 13, 2018
Friday, January 12, 2018
Wikipedia picture of the day on January 13, 2018: Whale Shark (Rhincodon typus). Face portrait of an 8-meter individual filter-feeding plankton at night. His eye is clearly visible. His upper lip shows recent scars – whale sharks steal food from fishermen nets and the fishermen hit them in the mouth to try to discourage them. Thaa Atoll, Maldives Wikipedia"
Thursday, January 11, 2018
Discovered with the PanSTARRS telescope on September 7, 2016, this Comet PanSTARRS, C/2016 R2, is presently about 24 light minutes (3 AU) from the Sun, sweeping through planet Earth's skies across the background of stars in the constellation Taurus. An inbound visitor from our Solar System's distant Oort Cloud, its beautiful and complex ion tail is a remarkable shade of blue. Still relatively far from the Sun, the comet's already well-developed ion tail is very impressive. Emission from unusually abundant ionized carbon monoxide (CO+) atoms fluorescing in the increasing sunlight is largely responsible for the pretty blue tint. This color image of the blue comet is a combination of data taken from two different telescopes during the night of January 7. Located at the apex of the V-shaped Hyades star cluster in Taurus, bright star Gamma Tauri is responsible for the glow at the bottom left corner of the frame. via NASA
Wednesday, January 10, 2018
Large and dramatically shaped, this cosmic cloud spans nearly 7 degrees or 14 full moons across planet Earth's sky toward the southern constellation Ara. Difficult to image, the filamentary apparition is cataloged as RCW 114 and traced in this telescopic mosaic by the telltale reddish emission of ionized hydrogen atoms. In fact, RCW 114 has been recognized as a supernova remnant. Its extensive filaments of emission are produced as the still expanding shockwave from the death explosion of a massive star sweeps up the surrounding interstellar medium. Consistent estimates place its distance at over 600 light-years, indicating a diameter of about 100 light-years or so. Light from the supernova explosion that created RCW 114 would have reached Earth around 20,000 years ago. A neutron star or pulsar has recently been identified as the collapsed remains of the stellar core. via NASA
Where do stars form when galaxies collide? To help find out, astronomers imaged the nearby galaxy merger NGC 2623 in high resolution with the Hubble Space Telescope. Analysis of this and other Hubble images as well as images of NGC 2623 in infrared light by the Spitzer Space Telescope, in X-ray light by XMM-Newton, and in ultraviolet light by GALEX, indicate that two originally spiral galaxies appear now to be greatly convolved and that their cores have unified into one active galactic nucleus (AGN). Star formation continues around this core near the featured image center, along the stretched out tidal tails visible on either side, and perhaps surprisingly, in an off-nuclear region on the upper left where clusters of bright blue stars appear. Galaxy collisions can take hundreds of millions of years and take several gravitationally destructive passes. NGC 2623, also known as Arp 243, spans about 50,000 light years and lies about 250 million light years away toward the constellation of the Crab (Cancer). Reconstructing the original galaxies and how galaxy mergers happen is often challenging, sometimes impossible, but generally important to understanding how our universe evolved. via NASA
Tuesday, January 9, 2018
Monday, January 8, 2018
Sunday, January 7, 2018
Wikipedia picture of the day on January 8, 2018: Buller's Albatross (Thalassarche bulleri) with a Short-tailed Shearwater (Ardenna tenuirostris) behind, East of the Tasman Peninsula, Tasmania, Australia. Wikipedia"
Saturday, January 6, 2018
One of the greatest unrequited legends of outer space is the tether. Tethers, long strands of material, hold the promise of stabilizing satellites, generating electricity, and allowing easy transportation. Possibly the most ambitious vision of the space tether is the space elevator popularized by Arthur C. Clarke, where a tether is constructed that connects the ground to geosynchronous orbit. One problem is strength - it is difficult to make a long useful tether that does not snap. Pictured here is the deployment of the Tethered Satellite System 1 (TSS-1) by the space shuttle Altantis in 1992. Like other tested tethers, TSS-1 failed to live up to its promise, although many valuable lessons were learned. via NASA
Lately, bright Jupiter and fainter Mars have been easy to spot for early morning skygazers. Before dawn on January 7 the two naked-eye planets will reach a close conjunction near the horizon, only 1/4 degree apart in predawn eastern skies. That apparent separation corresponds to about half the angular diameter of a Full Moon. Just off the wing of a high-flying aircraft in this snapshot from early morning January 5, Jupiter (left) and Mars (middle) are also lined-up with the well-balanced Zubenelgenubi (right), alpha star of the constellation Libra. Below are lights from central Europe near Prague, Czech Republic, planet Earth. via NASA
Friday, January 5, 2018
Thursday, January 4, 2018
A jewel of the southern sky, the Great Carina Nebula, also known as NGC 3372, is one of our galaxy's largest star forming regions. Easily visible to the unaided eye it stands high above the signature hill of Lake Ballard, ephemeral salt lake of Western Australia, in this serene night skyscape from December 25, 2017. The Milky Way itself stretches beyond the southern horizon. Along the Milky Way, bright stars Alpha and Beta Centauri lie just above the hill's right flank, with the Southern Cross and dark Coalsack Nebula above the hill top. Based on a 22 panel mosaic, the scene was cropped to reveal more closely the beauty of this region of the southern Milky Way. On that short summer night, a star tracking camera mount was used to record the mosaic images of the sky, but turned off to image the foreground in moonlight. via NASA
Wednesday, January 3, 2018
Tuesday, January 2, 2018
Monday, January 1, 2018
Why does the Perseus galaxy cluster shine so strangely in one specific color of X-rays? No one is sure, but a much-debated hypothesis holds that these X-rays are a clue to the long-sought identity of dark matter. At the center of this mystery is a 3.5 Kilo-electronvolt (KeV) X-ray color that appears to glow excessively only when regions well outside the cluster center are observed, whereas the area directly surrounding a likely central supermassive black hole is actually deficient in 3.5 KeV X-rays. One proposed resolution -- quite controversial -- is that something never seen before might be present: florescent dark matter (FDM). This form of particle dark matter might be able to absorb 3.5 KeV X-radiation. If operating, FDM, after absorption, might later emit these X-rays from all over the cluster, creating an emission line. However, when seen superposed in front of the central region surrounding the black hole, FDM's absorption would be more prominent, creating an absorption line. Pictured, a composite image of the Perseus galaxy cluster shows visible and radio light in red, and X-ray light from the Earth-orbiting Chandra Observatory in blue. via NASA
Wikipedia picture of the day on January 2, 2018: First stage of a Falcon 9 Full Thrust rocket on Landing Zone 1 (LZ-1). The stage landed successfully after launching 11 Orbcomm OG-2 telecommunication satellites to Low Earth orbit. Wikipedia"