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Tag: Astronomy

  • ‘Old Smoker’ Star Discovered Lurking in Milky Way Galaxy | High Times

    ‘Old Smoker’ Star Discovered Lurking in Milky Way Galaxy | High Times

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    A strange new type of star referred to by scientists as an “old smoker” has been discovered after a years-long astronomical study. 

    According to four different studies recently published in Monthly Notices of the Royal Astronomical Society, these recently discovered stellar objects are essentially really large and very old stars that emit puffs of what appears to be smoke and dust after many decades of inactivity. 

    These stars were discovered using a powerful giant telescope located deep in the mountains of Chile. Lead author of one study and co-author of the other three, Phillip Lucas, said that thus far, scientists are not completely sure what creates this effect in the old smoker stars. 

    “Everything we have been able to learn about them suggests that this is a case of stars throwing off puffs of smoke—for reasons that we don’t fully understand,” Lucas said. “We weren’t sure if these stars were protostars starting an eruption, or recovering from a dip in brightness caused by a disc or shell of dust in front of the star — or if they were older giant stars throwing off matter in the late stages of their life,” Lucas said

    Originally the studies were focused at finding newborn stars, oftentimes surrounded by dust and gasses making them hard to see. This is why the VISTA (Visible and Infrared Survey Telescope) in Chile, capable of seeing infrared light, was used to scan the skies for the stars other telescopes would not be able to see. As Dr. Zhen Guo, Fondecyt Postdoc Fellow at the University of Valparaiso in Chile and lead author of two studies explained, these newborn stars often help to form new solar systems over time. 

    “Our main aim was to find rarely-seen newborn stars, also called protostars, while they are undergoing a great outburst that can last for months, years, or even decades,” Guo said. “These outbursts happen in the slowly spinning disc of matter that is forming a new solar system. They help the newborn star in the middle to grow, but make it harder for planets to form. We don’t yet understand why the discs become unstable like this,” Guo said.

    The old smoker stars are a kind of red giant. Red giants are stars which have essentially expired, that is, they’ve run out of hydrogen fuel and have “died” in a sense. This often causes violent energy outbursts from the star for a while. Our own sun will go through this one day in the far off future, swallowing several of the inner planets in the course of its death according to NASA, though the fate of the Earth remains relatively unclear when this happens. Luckily, it’ll be several billion years before this occurs so it will more than likely be somebody else’s problem by then.  

    The team of scientists involved with these studies found several red giants, 21 to be exact, that appeared to be a bit different than those found in the past. They chose seven of these stars to focus on and noticed unusual characteristics that puzzled them, most noticeably the smoke and dust they appeared to exert which is how they received the moniker ‘old smoker.’ 

    “These elderly stars sit quietly for years or decades and then puff out clouds of smoke in a totally unexpected way,” said Dante Minniti, a professor in the department of physics at Andrés Bello University in Chile and coauthor on three of the studies, in a press release “They look very dim and red for several years, to the point that sometimes we can’t see them at all.”

    Most of the stars the team studied were found near the center or the nucleus if you will of the Milky Way Galaxy, known as the innermost nuclear disc. Lucas explained that these newly discovered stars could potentially play a role in the way elements are distributed across the galaxies.

    “Matter ejected from old stars plays a key role in the life cycle of the elements, helping to form the next generation of stars and planets,” Lucas said. “This was thought to occur mainly in a well-studied type of star called a Mira variable. However, the discovery of a new type of star that throws off matter could have wider significance for the spread of heavy elements in the Nuclear Disc and metal-rich regions of other galaxies.”

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    Patrick Maravelias

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  • NationalEclipse.com Declares 2024 'The Year of the Eclipse'

    NationalEclipse.com Declares 2024 'The Year of the Eclipse'

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    A Total Solar Eclipse Will Occur in the U.S. on April 8, 2024 — “The 2024 Eclipse Will Transcend the 2017 Eclipse” — Last Total Eclipse in the Lower 48 States for 20 Years

    NationalEclipse.com, one of the leading online resources about solar eclipses, has declared 2024 to be “The Year of the Eclipse.”

    Now less than three months away, a total solar eclipse will occur in North America on April 8, 2024. The “path of totality”—the narrow strip of land within which the eclipse will be “total”—will stretch from southwest to northeast, traveling through Mexico, the United States, and Canada. In the U.S., the path will cross 13 states, entering the country in Texas and exiting in Maine.

    The 2024 eclipse arrives only seven years after the last total solar eclipse occurred in America on August 21, 2017. According to Dave Clark, operator of NationalEclipse.com, the 2024 eclipse will transcend the 2017 eclipse in several major ways. “The path of the 2024 eclipse will cross over or come close to more major cities than in 2017, making it possible for millions of people to easily witness nature’s greatest show,” says Clark. “The eclipse also features a maximum duration of totality—the amount of time during which the Sun is totally eclipsed by the Moon—that’s almost two minutes longer than in 2017.”

    Clark also points out that the 2024 eclipse will be the final total solar eclipse in the contiguous United States for 20 years. Although a total eclipse will occur in Alaska in 2033, residents of the lower 48 states will have to wait until 2044 to witness another total solar eclipse after April 8, 2024.

    Due to the historic nature of the April 8, 2024, total solar eclipse, NationalEclipse.com has declared 2024 to be “The Year of the Eclipse” and encourages everyone to make plans to view this awe-inspiring event. “Many people who have seen a total solar eclipse describe it as one of the most spectacular natural events they’ve ever witnessed,” says Clark. “It’s truly a bucket list experience.”

    ABOUT NATIONALECLIPSE.COM

    Launched in 2015 to provide accurate and reliable information for the 2017 total solar eclipse in the U.S., NationalEclipse.com quickly became one of the leading online resources about solar eclipses, particularly for the upcoming 2024 total eclipse in North America. Featuring comprehensive information on the 2024 eclipse, as well as an Eclipse Store offering certified safe eclipse glasses and other in-demand eclipse items, thousands of people use NationalEclipse.com every day to research where and how to view the 2024 total solar eclipse.

    For more information on the 2024 eclipse, or for media requests, please contact Dave Clark at contact@nationaleclipse.com.

    Source: NationalEclipse.com

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  • True face of Neptune revealed debunking image that “bedeviled for decades”

    True face of Neptune revealed debunking image that “bedeviled for decades”

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    Neptune, one of our most distant planetary neighbors, may not be the color we’ve always thought it was.

    Previous images of far-off planets showed Neptune as being a deep electric blue, while Uranus appeared a sea-foam green. However, new images have revealed that the two planets are, in fact, much more similar in color to each other.

    Both planets are instead a similar shade of green-blue, according to a new paper in the journal Monthly Notices of the Royal Astronomical Society.

    “The misperception of Neptune’s color, as well as the unusual color changes of Uranus, have bedeviled us for decades. This comprehensive study should finally put both issues to rest,” Heidi Hammel, a Neptune and Uranus researcher at the Association of Universities for Research in Astronomy (AURA) who did not contribute towards the study, said in a statement.

    Images of Uranus and Neptune released after the Voyager 2 flybys in 1986 and 1989 compared with a reprocessing of the individual filter images in this study.
    Patrick Irwin

    The common misconception that Neptune was blue and Uranus green arose thanks to images taken by the NASA Voyager 2 mission, which snapped the two planets as it flew past the outer solar system. Voyage 2 took a variety of pictures of each planet in several separate colors, which were then combined to make composite color images.

    However, these composites were not accurately balanced to represent the “true” color of the planets, with Uranus appearing a pale green but Neptune seeming much too blue, exacerbated by increased contrast on the Neptune images.

    Astronomers have known for decades that the two planets were similar shades: both more similar to the traditional color of Uranus.

    “Although the familiar Voyager 2 images of Uranus were published in a form closer to ‘true’ color, those of Neptune were, in fact, stretched and enhanced, and therefore made artificially too blue,” Patrick Irwin, co-author of the paper and professor of astronomy at the University of Oxford, said in a statement.

    “Even though the artificially-saturated color was known at the time amongst planetary scientists – and the images were released with captions explaining it – that distinction had become lost over time,” he said. “Applying our model to the original data, we have been able to reconstitute the most accurate representation yet of the colour of both Neptune and Uranus.”

    neptune
    Voyager 2/ISS image of Neptune released shortly after the Voyager 2 flybys in 1989. Neptune is actually more similar to Uranus in color.
    Patrick Irwin

    The new paper revealed the true colors of the planets in images created using data from Hubble Space Telescope’s Space Telescope Imaging Spectrograph (STIS) and the Multi Unit Spectroscopic Explorer (MUSE) on the European Southern Observatory’s Very Large Telescope.

    The pictures show that the planets are very similar in hue, with Neptune having only a slight blue tinge as a result of the planet having a thinner layer of haze than Uranus.

    The study has also revealed why Uranus’s color appears to change somewhat during the course of its 84-year orbit of the sun. Between 1950 and 2916, Uranus has been spotted appearing more green during its summer and winter solstices, when its poles point more towards the sun, and more blue during its equinoxes.

    This is because of Uranus’s strange spin, almost on its side with its axis at nearly a right angle to our planet’s. Therefore, during the solstice, the poles are pointing nearly directly at the sun.

    This study describes a model that was developed to compare the light spectra of Uranus’s polar regions to its equatorial regions, showing how the reflectiveness of the regions differed and, thus, why the planet appears as being different colors during different periods of the orbit.

    The model reveals that Uranus’s polar regions reflect more green and red wavelengths than the equator due to the greater presence of methane—which absorbs red light rather than reflecting it—at the equator than the poles. Additionally, a haze of icy methane particles may also play into this color change.

    “This is the first study to match a quantitative model to imaging data to explain why the color of Uranus changes during its orbit,” Irwin said.

    “In this way, we have demonstrated that Uranus is greener at the solstice due to the polar regions having reduced methane abundance but also an increased thickness of brightly scattering methane ice particles.”

    Do you have a tip on a science story that Newsweek should be covering? Do you have a question about Neptune? Let us know via science@newsweek.com.