Categoría: Lo Inmenso

Big, beautiful spiral galaxy M101 is one of the last entries in Charles Messier’s famous catalog, but definitely not one of the least. About 170,000 light-years across, this galaxy is enormous, almost twice the size of our own Milky Way galaxy. M101 was also one of the original spiral nebulae observed by Lord Rosse’s large 19th century telescope, the Leviathan of Parsontown. M101 shares this modern telescopic field of view with more distant background galaxies, foreground stars within the Milky Way, and a companion dwarf galaxy NGC 5474 (lower right). The colors of the Milky Way stars can also be found in the starlight from the large island universe. Its core is dominated by light from cool yellowish stars. Along its grand design spiral arms are the blue colors of hotter, young stars mixed with obscuring dust lanes and pinkish star forming regions. Also known as the Pinwheel Galaxy, M101 lies within the boundaries of the northern constellation Ursa Major, about 23 million light-years away. Its companion NGC 5474 has likely been distorted by its past gravitational interactions with the dominant M101. [via NASA] https://ift.tt/2ChIam4

Mars exploration rover Opportunity’s parting panorama from Perseverance Valley spans 360 degrees in this false color mosaic. The scene is composed of 354 individual images recorded through 3 different color filters by the rover’s panoramic camera from May 13 through June 10, 2018. A few frames remain in black and white at the lower left though. Those were obtained through only one filter just before a dust storm engulfed Mars in June 2018, ultimately ending the solar-powered rover’s trailblazing 15 year mission. Just right of center, the annotation identifies Opportunity’s entry point to Perseverance Valley along the Endeavor crater’s western rim. The rover’s tracks begin there, extending from over the horizon toward the far right and its final resting spot on the Red Planet. [via NASA] https://ift.tt/2F42VSX

Are galaxies giant magnets? Yes, but the magnetic fields in galaxies are typically much weaker than on Earth’s surface, as well as more complex and harder to measure. Recently, though, the HAWC+ instrument onboard the airborne (747) SOFIA observatory has been successful in detailing distant magnetic fields by observing infrared light polarized by reflection from dust grains. Featured here, HAWC+ observations of the M82, the Cigar galaxy, show that the central magnetic field is perpendicular to the disk and parallel to the strong supergalactic wind. This observation bolsters the hypothesis that M82’s central magnetic field helps its wind transport the mass of millions of stars out from the central star-burst region. The featured image shows magnetic field lines superposed on top of an optical light (gray) and hydrogen gas (red) image from Kitt Peak National Observatory, further combined with infrared images (yellow) from SOFIA and the Spitzer Space Telescope. The Cigar Galaxy is about 12 million light years distant and visible with binoculars towards the constellation of the Great Bear. [via NASA] https://ift.tt/2XJQC6R

How can the Moon rise through a mountain? It cannot — what was photographed here is a moonrise through the shadow of a large volcano. The volcano is Mauna Kea, Hawai’i, USA, a frequent spot for spectacular photographs since it is one of the premier observing locations on planet Earth. The Sun has just set in the opposite direction, behind the camera. Additionally, the Moon has just passed full phase — were it precisely at full phase it would rise, possibly eclipsed, at the very peak of the shadow. The Moon is actually rising in the triangular shadow cone of the volcano, a corridor of darkness that tapers off in the distance like converging train tracks. The Moon is too large and too far away to be affected by the shadow of the volcano. Refraction of moonlight through the Earth’s atmosphere makes the Moon appear slightly oval. Cinder cones from old volcanic eruptions are visible in the foreground. [via NASA] https://ift.tt/2EYUEkq

Peering from the shadows, the Saturn-facing hemisphere of tantalizing inner moon Enceladus poses in this Cassini spacecraft image. North is up in the dramatic scene captured during November 2016 as Cassini’s camera was pointed in a nearly sunward direction about 130,000 kilometers from the moon’s bright crescent. In fact, the distant world reflects over 90 percent of the sunlight it receives, giving its surface about the same reflectivity as fresh snow. A mere 500 kilometers in diameter, Enceladus is a surprisingly active moon. Data collected during Cassini’s flybys and years of images have revealed the presence of remarkable south polar geysers and a possible global ocean of liquid water beneath an icy crust. [via NASA] https://ift.tt/2VO0QBf

Normally faint and elusive, the Jellyfish Nebula is caught in this alluring telescopic field of view. The entire scene is a two panel mosaic constructed using narrowband image data, with emission from sulfur, hydrogen and oxygen atoms shown in red, green and blue hues. It’s anchored right and left by two bright stars, Mu and Eta Geminorum, at the foot of the celestial twin. The Jellyfish Nebula itself is right of center, the brighter arcing ridge of emission with dangling tentacles. In fact, the cosmic jellyfish is part of bubble-shaped supernova remnant IC 443, the expanding debris cloud from a massive star that exploded. Light from the explosion first reached planet Earth over 30,000 years ago. Like its cousin in astrophysical waters the Crab Nebula supernova remnant, the Jellyfish Nebula is known to harbor a neutron star, the remnant of the collapsed stellar core. An emission nebula cataloged as Sharpless 249 fills the field at the upper left. The Jellyfish Nebula is about 5,000 light-years away. At that distance, this image would be about 300 light-years across. [via NASA] https://apod.nasa.gov/apod/ap190307.html

Where have all the sunspots gone? Last month the total number of spots that crossed our Sun was … zero. Well below of the long term monthly average, the Sun’s surface has become as unusually passive this solar minimum just like it did 11 years ago during the last solar minimum. Such passivity is not just a visual spectacle, it correlates with the Sun being slightly dimmer, with holes in the Sun’s corona being more stable, and with a reduced intensity in the outflowing solar wind. The reduced wind, in turn, cools and collapses Earth’s outer atmosphere (the thermosphere), causing reduced drag on many Earth-orbiting satellites. Pictured in inverted black & white on the left, the Sun’s busy surface is shown near solar maximum in 2012, in contrast to the image on the right, which shows the Sun’s surface last August, already without spots (for a few days), as solar minimum was setting in. Effects of this unusually static solar minimum are being studied. [via NASA] https://ift.tt/2NOqUcQ

What created these huge galactic superbubbles? Two of these unusual bubbles, each spanning thousands of light-years, were recently discovered near the center of spiral galaxy NGC 3079. The superbubbles, shown in purple on the image right, are so hot they emit X-rays detected by NASA’s Earth-orbiting Chandra X-Ray Observatory. Since the bubbles straddle the center of NGC 3079, a leading hypothesis is that they were somehow created by the interaction of the central supermassive black hole with surrounding gas. Alternatively, the superbubbles might have been created primarily by the energetic winds from many young and hot stars near that galaxy’s center. The only similar known phenomenon is the gamma-ray emitting Fermi bubbles emanating from the center of our Milky Way Galaxy, discovered 10 years ago in images taken by NASA’s Fermi satellite. Research into the nature of the NGC 3079 superbubbles will surely continue, as well as searches for high-energy superbubbles in other galaxies. [via NASA] https://ift.tt/2IQwmNy

Why are bullets of gas shooting out of the Orion Nebula? Nobody is yet sure. First discovered in 1983, each bullet is actually about the size of our Solar System, and moving at about 400 km/sec from a central source dubbed IRc2. The age of the bullets, which can be found from their speed and distance from IRc2, is very young — typically less than 1,000 years. As the bullets expand out the top of the Kleinmann-Low section of the Orion Nebula, a small percentage of iron gas causes the tip of each bullet to glow blue, while each bullet leaves a tubular pillar that glows by the light of heated hydrogen gas. The detailed image was created using the 8.1 meter Gemini South telescope in Chile with an adaptive optics system (GeMS). GeMS uses five laser generated guide stars to help compensate for the blurring effects of planet Earth’s atmosphere. [via NASA] https://ift.tt/2VwwqDm

The bright clusters and nebulae of planet Earth’s night sky are often named for flowers or insects. Though its wingspan covers over 3 light-years, NGC 6302 is no exception. With an estimated surface temperature of about 250,000 degrees C, the dying central star of this particular planetary nebula has become exceptionally hot, shining brightly in ultraviolet light but hidden from direct view by a dense torus of dust. This sharp close-up was recorded by the Hubble Space Telescope in 2009. The Hubble image data is reprocessed here, showing off the remarkable details of the complex planetary nebula. Cutting across a bright cavity of ionized gas, the dust torus surrounding the central star is near the center of this view, almost edge-on to the line-of-sight. Molecular hydrogen has been detected in the hot star’s dusty cosmic shroud. NGC 6302 lies about 4,000 light-years away in the arachnologically correct constellation of the Scorpion (Scorpius). [via NASA] https://ift.tt/2NK2cdH