ikenbot:

The Milky Way Band and Dark Skies

PSA:“That has to be superimposed - they photoshopped that on!” It’s understandable why a lot of you (and I do mean a lot) might be confused when confronting these vistas. But these are actual images of the milky way as seen under the best viewing conditions known to our planet, the dark skies. Due to the rapid growth of our civilization, we emit more light than we should and thus this darkens out many of our views and blocks us from making those wonderful necessary connections to the skies our minds desperately need. We can’t see the Milky Way band as seen above in many places, it’s always there though, rest assured, ready to greet us with its lovely stars. If we’re missing out on this.. is the way we use public lighting really as conventional as we believe it is? [Similar Posts: Losing the Dark - a Public Service Announcement on Light Pollution] [Losing The Dark: GIF set]

Images: Southern dream, Southwest Night, Three Roads To Galactic Paradise, Tropical milky way

electricspacekoolaid:

Puzzle of Spiral Galaxies Solved —“Self-perpetuating, Persistent, and Surprisingly Long Lived”

Some 15 percent of all galaxies in the visible Universe are spirals. The great fog-like clouds of stars, the oldest and largest galaxies in the Universe are ellipticals. Becasue ellipticals also include many of the smallest galaxies, they are the most numerous. Our own Milky Way, astronomers believe, is a spiral. Our solar system and Earth reside somewhere near one of its filamentous, swept-back arms. And nearly 70 percent of the galaxies closest to the Milky Way are spirals, suggesting they have taken the most ordinary of galactic forms in a universe with somewhere between 100 billion and 200 billion galaxies.

But a long-standing question has been: how do galaxies like the Milky Way get and maintain their characteristic arms has proved to be an enduring puzzle in astrophysics. How do the arms ofspiral galaxies arise? Do they change or come and go over time?*The answers to these and other questions are now coming into focus as researchers capitalize on powerful new computer simulations to follow the motions of as many as 100 million “stellar particles” as gravity and other astrophysical forces sculpt them into familiar galactic shapes.

Writing April 1 in The Astrophysical Journal, a team of researchers from the University of Wisconsin-Madison and Harvard-Smithsonian Center for Astrophysics report simulations that seem to resolve longstanding questions about the origin and life history of spiral arms in disk galaxies.

“We show for the first time that stellar spiral arms are not transient features, as claimed for several decades,” says UW-Madison astrophysicist Elena D’Onghia, who led the new research along with Harvard-Smithsonian Center for Astrophysics colleagues Mark Vogelsberger and Lars Hernquist. “They are self-perpetuating, persistent and surprisingly long lived.”

The origin and fate of the emblematic spiral arms in disk galaxies have been debated by astrophysicists for decades, with two theories predominating: One holds that the arms come and go over time. A second and widely held theory is that the material that makes up the arms – stars, gas and dust – is affected by differences in gravity and jams up, like cars at rush hour, sustaining the arms for long periods.

The new results fall somewhere in between the two theories and suggest that the arms arise in the first place as a result of the influence of giant molecular clouds, star forming regions or nurseries common in galaxies. Introduced into the simulation, the clouds, says D’Onghia, a UW-Madison professor of astronomy, act as “perturbers” and are enough to not only initiate the formation of spiral arms but to sustain them indefinitely.

“We find they are forming spiral arms,” explains D’Onghia. “Past theory held the arms would go away with the perturbations removed, but we see that (once formed) the arms self-perpetuate, even when the perturbations are removed. It proves that once the arms are generated through these clouds, they can exist on their own through (the influence of) gravity, even in the extreme when the perturbations are no longer there.”

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mothernaturenetwork:

Black hole in Milky Way prepares to gobble up space cloud

The cosmic spectacle should offer scientists a chance to test some of their theories about how black holes pull in mass.

Milky Way Panorama from Mauna Kea 

Image Credit & Copyright: Wally Pacholka (TWAN)

“Aloha and welcome to a breathtaking skyscape. The dreamlike panoramic view looks out from the 4,200 meter volcanic summit of Mauna Kea, Hawai’i, across a layer of clouds toward a starry night sky and the rising Milky Way. Anchoring the scene on the far left is the dome of the Canada-France-Hawaii Telescope (CFHT), with north star Polaris shining beyond the dome to the right. Farther right, headed by bright star Deneb, the Northern Cross asterism is embedded along the plane of the Milky Way as it peeks above the horizon. Both Northern Cross and brilliant white Vega hang over a foreground grouping of cinder cones. Near the center are the reddish nebulae, stars and dust clouds of thecentral Milky Way. Below, illumination from the city lights of Hilo creates an eerie, greenish glow in the clouds. Red supergiant star Antares shines above the Milky Way’s central bulge while bright Alpha Centauri lies still farther right, along the dusty galactic plane. Finally, at the far right is the large Gemini North Observatory. The compact group of stars known as the Southern Cross is just left of the telescope dome. Need some help identifying the stars? Just slide your cursor over the picture, or download this smaller, labeled panorama.”

electricspacekoolaid:

Ancient DNA Precursors Found in Interstellar Clouds - Predating Formation of Solar System

During the past decade, astrochemists have found that DNA molecules, the fundamental building blocks of life, find their origins not on Earth, but in the Cosmos. They are the languange of the Universe —the information they inherited comes from the stars and the cosmic ecology that formed them. Scientists using the National Science Foundation’s Green Bank Telescope (GBT) in West Virginia to study a giant cloud of gas some 25,000 light-years from Earth, near the center of our Milky Way Galaxy, have discovered a molecule thought to be a precursor to a key component of DNA and another that may have a role in the formation of the amino acid alanine.

 ”Finding these molecules in an interstellar gas cloud means that important building blocks for DNA and amino acids can ‘seed’ newly-formed planets with the chemical precursors for life,” said Anthony Remijan, of the National Radio Astronomy Observatory (NRAO).

One of the newly-discovered molecules, called cyanomethanimine, is one step in the process that chemists believe produces adenine, one of the four nucleobases that form the “rungs” in the ladder-like structure of DNA. The other molecule, called ethanamine, is thought to play a role in forming alanine, one of the twenty amino acids in the genetic code.

In each case, the newly-discovered interstellar molecules are intermediate stages in multi-step chemical processes leading to the final biological molecule. Details of the processes remain unclear, but the discoveries give new insight on where these processes occur.

Previously, scientists thought such processes took place in the very tenuous gas between the stars. The new discoveries, however, suggest that the chemical formation sequences for these molecules occurred not in gas, but on the surfaces of ice grains in interstellar space.

“We need to do further experiments to better understand how these reactions work, but it could be that some of the first key steps toward biological chemicals occurred on tiny ice grains,” Remijan said.

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Fisheye view of the Southern Sky’s Milky Way and it’s constellations.

Credit: ESO/S. Brunier

Milky Way Panorama.

“A panorama at one of my favorite new spots. This photo is over 180 degrees of view. The strong flares are from lights on concrete bunkers. The panorama is consisted of 7 images and it was taken with the Canon 5D Mark iii. The Milky Way is not a composite.”

Rare 360-degree Panorama of the Southern Sky

Credit: ESO/H.H. Heyer

“The Milky Way arches across this rare 360-degree panorama of the night sky above the Paranal platform, home of ESO’s Very Large Telescope. The image was made from 37 individual frames with a total exposure time of about 30 minutes, taken in the early morning hours. The Moon is just rising and the zodiacal light shines above it, while the Milky Way stretches across the sky opposite the observatory. 

The open telescope domes of the world’s most advanced ground-based astronomical observatory are all visible in the image: the four smaller 1.8-metre Auxiliary Telescopes that can be used together in the interferometric mode, and the four giant 8.2-metre Unit Telescopes. To the right in the image and below the arc of the Milky Way, two of our galactic neighbours, the Small and Large Magellanic Clouds, can be seen.”

An amazing interactive virtual tour is available here

The Aurora Borealis, Milky Way, and endless stars by Ragnar TH

ISS and the Summer Milky Way. 

Image Credit & Copyright: Luis Argerich

“Clouds on a summer night frame this sea and skyscape, recorded earlier this month near Buenos Aires, Argentina. But planet Earth’s clouds are not the only clouds on the scene. Starry clouds and nebulae along the southern hemisphere’s summer Milky Way arc above the horizon, including the dark Coal Sack near the Southern Cross and the tantalizing pinkish glow of the Carina Nebula. Both the Large (top center) and Small Magellanic Clouds are also in view, small galaxies in their own right and satellites of the Milky Way up to 200,000 light-years distant. Alpha star of the Carina constellation and second brightest star in Earth’s night, Canopus shines above about 300 light-years away. Still glinting in sunlight at an altitude of 400 kilometers, the orbiting International Space Station traces a long streak through the single, 5 minute, star-tracking exposure.”

Night photography inspiration by David Kaplan.

Our Place in the Cosmos by Alex Noriega.

“My camp on eastern Oregon’s Alvord desert playa, under the Milky Way.”

From the Milky Way to Virgo: A virtual tour through our Galaxy and the ‘Virgo Cluster’ our galactic neighborhood. 

“Starting in our Milky Way facing the Orion constellation we take off on a short journey from within the solar neighborhood passing some well-known objects in the Milky Way disk, then taking off and escaping our Galaxy heading into intergalactic space, again passing by some good old friends (nearby galaxies). Once in pure isolation we make our way toward a large filament of galaxies that leads us to the Virgo cluster of galaxies where we end our trip floating into the center of the central giant elliptical galaxy M87 with its jet that is powered by the central supermassive black hole. 

Even with a little bit of stack distortion, it is a quite interesting insight of how vast our surrounded space actually is.

Apart from the image of the Milky Way Galaxy, all images of Nebulae and Galaxies in the tour are real images taken with ground based and space telescopes.”

African Skyline

Milky Way Over Quiver Tree Forest 

Image Credit & Copyright: Florian Breuer

“In front of a famous background of stars and galaxies lies some of Earth’s more unusual trees. Known as quiver trees, they are actually succulent aloe plants that can grow to tree-like proportions. The quiver tree name is derived from the historical usefulness of their hollowed branches as dart holders. Occurring primarily in southern Africa, the trees pictured in the above 16-exposure composite are in Quiver Tree Forest located in southern Namibia. Some of the tallest quiver trees in the park are estimated to be about 300 years old. Behind the trees is light from the small town of Keetmanshoop, Namibia. Far in the distance,arching across the background, is the majestic central band of our Milky Way Galaxy. Even further in the distance, visible on the image left, are the Large and Small Magellanic Clouds, smaller satellite galaxies of the Milky Way that are prominent in the skies of Earth’s southern hemisphere.”