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    Lightbulb Astronomy & Cosmology

    Granny wonderin' how dey s'posed to find it if ya can't see it?...

    Quasars illustrate dark energy's roller coaster ride
    13 November 2012 - BOSS data is acquired by the 2.5m Sloan telescope at Apache Point Observatory in the US
    Scientists have used a novel technique to probe the nature of dark energy some 10 billion years into the past. They hope it will bring them closer to an explanation for the strange force that appears to be driving the Universe apart at an accelerating rate. The method relies on bright but distant objects known as quasars to map the spread of hydrogen gas clouds in space. The 3D distribution of these clouds can be used as a tracer for the influence of dark energy through time. A scholarly paper describing the approach has been submitted to the journal Astronomy & Astrophysics and posted on the arXiv.org preprint site. It is authored by the BOSS (Baryon Oscillation Spectroscopic Survey) team, which uses the 2.5m Sloan Foundation Telescope in New Mexico, US, to make its observations of the sky.

    The international group's new data is said to be a very neat fit with theory, confirming ideas that dark energy did not have a dominant role in the nascent Universe. Back then, gravity actually held sway, decelerating cosmic expansion. Only later did dark energy come to the fore. "We know very little about dark energy but one of our ideas is that it is a property of space itself - when you have more space, you have more energy," explained Dr Matthew Pieri, a BOSS team-member. "So, dark energy is something that increases with time. As the Universe expands, it gives us more space and therefore more energy, and at some point dark energy takes over from gravity to end the deceleration and drive an acceleration," the Portsmouth University, UK, researcher told BBC News.


    The BOSS team used 48,000 distant quasars to "back-light" and map the distribution of clouds of hydrogen gas in the early Universe

    The discovery that everything in the cosmos is now moving apart at a faster and faster rate was one of the major breakthroughs of the 20th Century. But scientists have found themselves grasping for new physics to try to explain this extraordinary phenomenon. A number of techniques are being deployed to try to get some insight. One concerns so-called baryon acoustic oscillations. These refer to the pressure-driven waves that passed through the post-Big-Bang Universe and which subsequently became frozen into the distribution of matter once it had cooled to a sufficient level. Today, those oscillations show themselves as a "preferred scale" in the spread of galaxies - a slight excess in the numbers of such objects with separations of 500 million light-years.

    It is an observation that can be used as a kind of standard ruler to measure the geometry of the cosmos. The BOSS team has already done this using a large volume of galaxies that stretch some six billion light-years from Earth. But at greater distances - and hence deeper in cosmic time - these standard galaxies are simply too faint for the Sloan telescope to see. Instead, the BOSS team has used quasars (quasi-stellar radio sources) to help it map the cosmos. Quasars are far flung galaxies where a massive central black hole is driving the emission of huge amounts of electromagnetic radiation. These are visible to Sloan.

    More http://www.bbc.co.uk/news/science-environment-20303592

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  3. #2
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    DonGlock26's Avatar Senior Member
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    Amazing.

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    Lightbulb

    Hubble spots dark vortex on Neptune...

    Hubble locates new dark spot on Neptune
    June 23, 2016 - The last several Neptune vortices seen by astronomers have exhibited a wide range of sizes and shapes.
    There's a new dark spot on Neptune, the farthest planet from the sun. Astronomers recently confirmed the presence of a dark vortex spinning across the planet's atmosphere after examining imagery collected by the Hubble Space Telescope last month. It's the first Neptune vortex discovered since 1994.

    The high pressure system is accompanied by bright companion clouds. Researchers believe the clouds are formed as the vortex pushes ambient air higher into the atmosphere, forcing gases to freeze into methane ice crystals. "Dark vortices coast through the atmosphere like huge, lens-shaped gaseous mountains," Mike Wong, a researcher astronomer at the University of California, Berkeley, said in a news release. "And the companion clouds are similar to so-called orographic clouds that appear as pancake-shaped features lingering over mountains on Earth."


    Wong led the investigation of Hubble data that yielded the discovery of the new dark spot. Jupiter hosts similar cyclone-like disturbances, but the gas giant's vortices are more uniform and sometimes persist, slowly evolving, for decades. Previous studies have proven Neptune's vortices to be a permanent feature, but the disturbances are shorter-lived.

    The last several Neptune vortices seen by astronomers have exhibited a wide range of sizes and shapes, and have proven to be relatively unstable -- wandering north and south, speeding up and slowing down. Scientists hope further monitoring of Neptune's vortices will illuminate how they originate and the factors that influence their fluctuations.

    http://www.upi.com/Science_News/2016...?spt=sec&or=sn
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    ‘Dark Vortex’ Spotted on Neptune
    June 24, 2016 - The vortex is about the same size as the US
    Astronomers have spotted a “dark vortex” swirling in Neptune’s atmosphere. Using high resolution images captured in May by the Hubble Space Telescope, researchers say the vortex is about the size of the continental United States.

    The vortex is a high pressure system and is accompanied by bright clouds. In 2015, astronomers spotted clouds and later a dark spot nearby. The May 2016 images confirmed the presence of the vortex. "Dark vortices coast through the atmosphere like huge, lens-shaped gaseous mountains," said University of California at Berkeley research astronomer Mike Wong. "And the companion clouds are similar to so-called orographic clouds that appear as pancake-shaped features lingering over mountains on Earth." Vortices on Neptune have been spotted before. In 1989, the Voyager 2 spacecraft saw one, and in 1994, Hubble pinpointed one.


    A dark vortex was spotted on Neptune.

    Astronomers say the vortices “have exhibited surprising diversity over the years, in terms of size, shape, and stability (they meander in latitude, and sometimes speed up or slow down).” They also have relatively short lifespans compared to anticyclones seen on Jupiter, which “evolve over decades. Further study should yield a better understanding about how vortices develop, what causes them to move and how they interact with the environment, researchers said. Neptune is roughly 4.3 billion kilometers from the Sun, and it takes 165 Earth years to make one orbit of the sun.

    http://www.voanews.com/content/mht-d...e/3390910.html

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    Cool info, but as a member of "Friends of Pluto" I must take exception to calling Neptune the farthest planet.
    So, are you voting Douche Bag or Turd Sandwich this election?

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    Cool

    Granny says, "Dat's right - dem space aliens is havin' a laser light show on Jupiter...

    Bright Lights, Strange Sounds Detected on Jupiter
    July 01, 2016 - NASA has released a photo showing glowing auroras on Jupiter.
    The image was taken using the Hubble Space Telescope and shows the auroras, which are bigger than Earth, lighting up the gas giant’s poles. While Earth also has auroras, they’re caused by solar storms as opposed to Jupiter’s, which are caused by the massive planet pulling in charged particles from its surroundings as well as the solar winds. "These auroras are very dramatic and among the most active I have ever seen", says Jonathan Nichols from Britain's University of Leicester and principal investigator of the study. "It almost seems as if Jupiter is throwing a firework party for the imminent arrival of Juno." The Juno space probe is days away from a rocket burn that will insert the spacecraft into Jupiter’s orbit later this month.


    This image combines an image taken with Hubble Space Telescope in the optical (taken in spring 2014) and observations of its auroras in the ultraviolet

    The probe recently detected odd sounds coming from Jupiter, which NASA describes as a bow shock. “The bow shock is analogous to a sonic boom,” researcher William Kurth of the University of Iowa in Iowa City, said in a NASA news release. “The solar wind blows past all the planets at a speed of about a million miles per hour, and where it hits an obstacle, there’s all this turbulence.” During its mission, Juno will make 37 “close approaches” to Jupiter, and each one could imperil the craft. For example, under the clouds, there is a layer of hydrogen under so much pressure that it conducts electricity. That, along with the planet’s fast rotation [one day on Jupiter is only 10 hours long], creates a strong magnetic field, creating what NASA calls the “harshest radiation environment in the solar system.”

    Juno is fitted with “radiation-hardened electrical wiring and shielding” as well as a unique titanium vault that protects the probe’s most vital equipment, such as the flight computer. The vault is so strong that it will reduce radiation exposure by 800 times. Without it, “Juno's electronic brain would more than likely fry before the end of the very first flyby of the planet.” To further mitigate the exposure, Juno’s orbit around the planet will be unusual, as described in the video below.

    http://www.voanews.com/content/mht-b...r/3400199.html

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    Cool

    Odd goin'-ons in outer space...

    Astronomers Spy Giant Planet, Three Stars in Odd Celestial Ballet
    July 07, 2016 — Astronomers have discovered a planet unlike any other ever found, one that loops widely around one star that is locked in a gravitational embrace with two others in a triple-star system, creating a curious celestial ballet. The findings, published Thursday in the journal Science, challenge current notions about what makes a planetary system viable.
    With three stars in the system, the massive planet would experience triple sunrises and triple sunsets during one season and all daylight in another. Since the planet's orbit is very long, each season lasts for hundreds of years. "Depending on which season you were born in, you may never know what nighttime is like," lead researcher Kevin Wagner of the University of Arizona said. The planet, called HD 131399Ab, is about four times bigger than Jupiter, the largest planet in our solar system, and is orbiting in a three-star system located about 340 light-years from Earth in the constellation Centaurus. Scientists are not sure how HD 131399Ab came to exist. It orbits its parent star about twice as far as Pluto circles the sun, needing 550 years to complete a single orbit.


    This artist's impression shows a view of the triple star system HD 131399 from close to the giant planet orbiting in the system. The planet is known as HD 131399Ab and appears at the lower-left of the picture.

    Astronomers have previously discovered planets in multi-star systems, but never one that circles a parent star with such a wide berth. It also is one of the few extrasolar planets — those outside our solar system — to be directly imaged by telescope. The planet's orbit is akin to the distance more typically seen when a star orbits another star, not a planet orbiting a star. "This is the first planet that we've found with an orbit that is comparable to that of the stars," Wagner said. If HD 131399Ab's orbit was just a bit wider, computer simulations show it could be gravitationally elbowed out of the system by the pair of smaller stars that orbit each other and the main star, which is about 80 percent bigger than the sun.

    Though the planet is relatively young, around 16 million years old compared to the 4.5-billion-year-old Earth, it likely has had an eventful life. Scientists suspect it may have started off in a much closer orbit around two parent stars before it was gravitationally bounced to its extreme distance. Scientists plan additional observations to determine if the planet's orbit is actually stable. "It is not clear how this planet ended up on its wide orbit in this extreme system ... but it shows there is more variety out there than many would have deemed possible," Wagner said. The planet was detected using the European Southern Observatory's Very Large Telescope in northern Chile.

    http://www.voanews.com/content/astro...a/3408452.html
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    Water Clouds May Float in Dwarf Star’s Atmosphere
    July 07, 2016 - Astronomers say they’ve collected evidence that points to the existence of the first water, or water ice, clouds detected outside the solar system.
    Writing in the Astrophysical Journal Letters, scientists from the University of California Santa Cruz say the brown dwarf called WISE 0855, which is a mere 7.2 light-years from Earth, likely has the clouds in its atmosphere. Using the Gemini North telescope in Hawaii, researchers scanned WISE 0855, the coldest known object outside the solar system, in the infrared spectrum, which yielded “the first details of the object's composition and chemistry.” "We would expect an object that cold to have water clouds, and this is the best evidence that it does," said Andrew Skemer, assistant professor of astronomy and astrophysics at UC Santa Cruz and first author of the study.

    Brown dwarfs are often referred to as failed stars, because they never gained quite enough mass to cause the nuclear fusion reactions that make them shine. WISE 0855 is about five times the mass of the gas giant Jupiter. "WISE 0855 is our first opportunity to study an extrasolar planetary-mass object that is nearly as cold as our own gas giants," Skemer said.


    Artist's rendering of WISE 0855 as it might appear if viewed up close in infrared light.

    Because WISE 0855 is so faint, researchers had to look at “thermal emission from the deep atmosphere at wavelengths in a narrow window” to gain insight into the composition of its atmosphere. "It's five times fainter than any other object detected with ground-based spectroscopy at this wavelength," Skemer said. "Now that we have a spectrum, we can really start thinking about what's going on in this object. Our spectrum shows that WISE 0855 is dominated by water vapor and clouds, with an overall appearance that is strikingly similar to Jupiter."

    The two bodies, researchers say, have “strikingly similar” spectra “with respect to water absorption” but that WISE 0855 likely has a less turbulent atmosphere than Jupiter.

    http://www.voanews.com/content/mht-w...e/3407842.html
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    Saturn’s Moon, Titan, Could Support Life
    July 06, 2016 - Titan, one of Saturn’s moons, could support a very different kind life, according to a new study.
    Writing in the Proceedings of the National Academy of Sciences, researchers from Cornell University say that despite the moon’s harsh environment, a “prebiotic chemical key” likely exists in the form of hydrogen cyanide. The compound is produced when sunlight interacts with the moon’s “toxic” atmosphere made up of nitrogen and methane. The conclusion was reached based on data from NASA’s Cassini and Huygen’s missions.


    Titan is seen from the Huygens probe as it descended to the surface

    Hydrogen cyanide is an organic chemical capable of reacting with other molecules, “forming long chains, or polymers, one of which is called polyimine. Polyimine is flexible, which helps mobility under very cold conditions, and it can absorb the sun’s energy and become a possible catalyst for life,” researchers said. “Polyimine can exist as different structures, and they may be able to accomplish remarkable things at low temperatures, especially under Titan’s conditions,” said Martin Rahm, postdoctoral researcher in chemistry and lead author of the new study. This paper is a starting point, as we are looking for prebiotic chemistry in conditions other than Earth’s. “We are used to our own conditions here on Earth. Our scientific experience is at room temperature and ambient conditions. Titan is a completely different beast.”

    Other moons in the solar system have also been identified as having conditions that could support life, including Saturn’s Enceladus and Jupiter’s Europa. While both Earth and Titan have flowing liquids in the form of lakes, rivers and oceans, on Titan they are filled with liquid methane and ethane, not water. Also, the moon is too cold to have liquid water. “We need to continue to examine this, to understand how the chemistry evolves over time. We see this as a preparation for further exploration,” said Rahm. “If future observations could show there is prebiotic chemistry in a place like Titan, it would be a major breakthrough. This paper is indicating that prerequisites for processes leading to a different kind of life could exist on Titan, but this only the first step,” he added.

    http://www.voanews.com/content/mht-s...e/3406796.html

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