Welcome to the WWII Forums! Log in or Sign up to interact with the community.

For the other Astronuts out there

Discussion in 'Free Fire Zone' started by Biak, Nov 2, 2011.

  1. Biak

    Biak Adjutant Staff Member Patron  

    Joined:
    Nov 15, 2009
    Messages:
    7,800
    Likes Received:
    1,833
    And the search continues
    https://phys.org/news/2022-08-black-hole-collisiofast-universe.ht

    A major ongoing scientific debate is - exactly how fast the universe is expanding—a number called the Hubble constant. The different methods available so far yield slightly different answers, and scientists are eager to find alternate ways to measure this rate. Checking the accuracy of this number is especially important because it affects our understanding of fundamental questions like the age, history and makeup of the universe.

    The new study offers a way to make this calculation, using special detectors that pick up the cosmic echoes of black hole collisions.

    Occasionally, two black holes will slam into each other—an event so powerful that it literally creates a ripple in space-time that travels across the universe. Here on Earth, the U.S. Laser Interferometer Gravitational-Wave Observatory (LIGO) and the Italian observatory Virgo can pick up those ripples, which are called gravitational waves.

    Over the past few years, LIGO and Virgo have collected the readings from almost 100 pairs of black holes colliding.

    The signal from each collision contains information about how massive the black holes were. But the signal has been traveling across space, and during that time the universe has expanded, which changes the properties of the signal. "For example, if you took a black hole and put it earlier in the universe, the signal would change and it would look like a bigger black hole than it really is," explained UChicago astrophysicist Daniel Holz, one of the two authors on the paper.

    If scientists can figure out a way to measure how that signal changed, they can calculate the expansion rate of the universe. The problem is calibration: How do they know how much it changed from the original?

    In their new paper, Holz and first author Jose María Ezquiaga suggest that they can use our newfound knowledge about the whole population of black holes as a calibration tool. For example, current evidence suggests that most of the detected black holes have between five and 40 times the mass of our sun. "So we measure the masses of the nearby black holes and understand their features, and then we look further away and see how much those further ones appear to have shifted," said Ezquiaga, a NASA Einstein Postdoctoral Fellow and Kavli Institute for Cosmological Physics Fellow working with Holz at UChicago. "And this gives you a measure of the expansion of the universe."
    The authors dub it the "spectral siren" method, a new approach to the 'standard siren' method which Holz and collaborators have been pioneering. (The name is a reference to the 'standard candle' methods also used in astronomy.)
    The scientists are excited because in the future, as LIGO's capabilities expand, the method may provide a unique window into the "teenage" years of the universe—about 10 billion years ago—that are hard to study with other methods.
    Researchers can use the cosmic microwave background to look at the very earliest moments of the universe, and they can look around at galaxies near our own galaxy to study the universe's more recent history. But the in-between period is harder to reach, and it's an area of special scientific interest.
    "It's around that time that we switched from dark matter being the predominant force in the universe to dark energy taking over, and we are very interested in studying this critical transition," said Ezquiaga.
    The other advantage of this method, the authors said, is that there are fewer uncertainties created by gaps in our scientific knowledge. "By using the entire population of black holes, the method can calibrate itself, directly identifying and correcting for errors," Holz said. The other methods used to calculate the Hubble constant rely on our current understanding of the physics of stars and galaxies, which involves a lot of complicated physics and astrophysics. This means the measurements might be thrown off quite a bit if there's something we don't yet know.

    By contrast, this new black hole method relies almost purely on Einstein's theory of gravity, which is well-studied and has stood up against all the ways scientists have tried to test it so far.

    The more readings they have from all black holes, the more accurate this calibration will be. "We need preferably thousands of these signals, which we should have in a few years, and even more in the next decade or two," said Holz. "At that point it would be an incredibly powerful method to learn about the universe."
     
  2. OpanaPointer

    OpanaPointer I Point at Opana Staff Member Patron   WW2|ORG Editor

    Joined:
    Jun 5, 2008
    Messages:
    15,907
    Likes Received:
    4,935
    [​IMG]

    Stargate Milky Way
    Image Credit & Copyright: Maxime Oudoux

    Explanation: There is a huge gate of stars in the sky, and you pass through it twice a day. The stargate is actually our Milky Way Galaxy, and it is the spin of the Earth that appears to propel you through it. More typically, the central band of our Milky Way appears as a faint band stretching across the sky, only visible in away from bright city lights. In a long-exposure wide-angle image from a dark location like this, though, the Milky Way's central plane is easily visible. The featured picture is a digital composite involving multiple exposures taken on the same night and with the same camera, but employing a stereographic projection that causes the Milky Way to appear as a giant circular portal. Inside the stargate-like arc of our Galaxy is a faint stripe called zodiacal light -- sunlight reflected by dust in our Solar System. In the foreground are cacti and dry rocks found in the rough terrain of the high desert of Chile, not far from the El Sauce Observatory and the developing Vera Rubin Observatory, the latter expected to begin routine operations in 2024.
     
  3. Biak

    Biak Adjutant Staff Member Patron  

    Joined:
    Nov 15, 2009
    Messages:
    7,800
    Likes Received:
    1,833
    Lord get me outta' here !

    upload_2022-8-17_20-42-3.png
     
    OpanaPointer likes this.
  4. Biak

    Biak Adjutant Staff Member Patron  

    Joined:
    Nov 15, 2009
    Messages:
    7,800
    Likes Received:
    1,833
    Words escape me ;


    Phantom_Galaxy_across_the_spectrum_article.jpg

    European Space Agency

    Edit: forgot link. But I did find if I download the image it's not too large to upload ??
     
    Last edited: Aug 29, 2022
    OpanaPointer likes this.
  5. Biak

    Biak Adjutant Staff Member Patron  

    Joined:
    Nov 15, 2009
    Messages:
    7,800
    Likes Received:
    1,833
    Trying something else,

    Multi-observatory_views_of_M74_article.jpg

    Hey I think it works !
     
    OpanaPointer likes this.
  6. OpanaPointer

    OpanaPointer I Point at Opana Staff Member Patron   WW2|ORG Editor

    Joined:
    Jun 5, 2008
    Messages:
    15,907
    Likes Received:
    4,935
    "My god! It's full of stars!"
     
  7. OpanaPointer

    OpanaPointer I Point at Opana Staff Member Patron   WW2|ORG Editor

    Joined:
    Jun 5, 2008
    Messages:
    15,907
    Likes Received:
    4,935
    [​IMG]

    Siccar Point on Mars
    Image Credit: NASA/JPL-Caltech/MSSS; Processing & License: Kevin M. Gill

    Explanation: What created this unusual hill on Mars? No one is sure. A good outlook to survey the surrounding area, Siccar Point stands out from its surroundings in Gale Crater. The unusual mound was visited by the robotic Curiosity rover exploring Mars late last year. Siccar Point not only has a distinctive shape, it has dark rocks above lighter rocks. The apparent much younger age of the dark rocks indicates a time-break in the usual geological ordering of rock layers -- by a process yet unknown. The Martian hill is named for Siccar Point on Earth, a place in Scotland itself distinctive as a junction between two different rock layers. Curiosity continues to explore Gale crater on Mars, looking for clues of ancient life. Simultaneously, 2300 kilometers away, its sister rover Perseverance explores Jezero crater, there assisted by the flight-capable scout Ingenuity.
     
  8. Biak

    Biak Adjutant Staff Member Patron  

    Joined:
    Nov 15, 2009
    Messages:
    7,800
    Likes Received:
    1,833
    JWST is just getting started.

    NASA's James Webb Space Telescope has captured its first direct images of a planet beyond our solar system.

    The planet, called HIP 65426 b, is a gas giant with no rocky surface, which means it likely cannot support alien life, according to astronomers who described the images in a NASA blog post published Thursday. The scientists are preparing a paper about the observations, but the findings have yet to be peer-reviewed.

    220901-exoplanet-photo-se-1247p-dc06ac.jpeg

    The observations are notable, however, because they hint at how the Webb telescope could be used to search for potentially habitable planets elsewhere in the universe.

    "This is a transformative moment, not only for Webb but also for astronomy generally," Sasha Hinkley, an associate professor of physics and astronomy at the University of Exeter in the United Kingdom, said in a statement. Hinkley led the observations of HIP 65426 b with an international team.
    The exoplanet is located about 355 light-years away from Earth and was first discovered in 2017, according to NASA. The gas giant is up to 12 times the mass of Jupiter and its orbit is around 100 times farther from its host star than Earth is from the sun.

    NASA said the Webb telescope will be able to glean new details about HIP 65426 b, including a more precise measurement of its mass and age. Astronomers estimate that the exoplanet is about 15 million to 20 million years old, which means it’s a relatively young world compared to Earth, which is 4.5 billion years old
    NBC News - Breaking News & Top Stories - Latest World, US & Local News
     
  9. Biak

    Biak Adjutant Staff Member Patron  

    Joined:
    Nov 15, 2009
    Messages:
    7,800
    Likes Received:
    1,833
    WIRED - The Latest in Technology, Science, Culture and Business

    TODAY IS THE 45th anniversary of the launch of Voyager 1, one of humanity’s iconic twin emissaries to the cosmos. (Its sibling, Voyager 2, launched a couple of weeks earlier.) Now in the dark, far reaches of interstellar space—more than 10 billion miles from home, where our sun looks like any other bright star—the pair are still doing science. They carry with them the Golden Records, bearing the sounds and symbols of Earth, should some extraterrestrial ever rendezvous with one of the spacecraft and become curious about its distant sender.
    “I’ve been following the arc of Voyager over my career,” says Linda Spilker, Voyager’s deputy project scientist at NASA’s Jet Propulsion Laboratory, who started at the agency in 1977, the year the probes launched. “I’m amazed at how long both of these spacecraft, Voyager 1 and Voyager 2, have been able to keep going and return unique science about new places that no spacecraft has visited before. And now they’ve become interstellar travelers. How cool is that?”

    The two car-sized probes, each with a 12-foot antenna mounted on top, had one primary task: to visit the gas giants in our own solar system. After their launches, the Voyagers’ paths diverged, but they both took advantage of a rare planetary lineup, snapping groundbreaking photos as they flew by Jupiter, Saturn, Uranus, and Neptune and revealed tantalizing details about the planets’ moons. By the end of 1989, they’d completed that mission. In 1990, Voyager 1 capped it by turning around and taking a poignant image of our own world, which astronomer and science communicator Carl Sagan dubbed the Pale Blue Dot.

    “Look again at that dot. That’s here. That’s home. That’s us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, has lived out their lives,” Sagan wrote. The image of the Earth from a cosmic perspective—a mere “mote of dust suspended in a moonbeam,” as he put it—became nearly as memorable as the Earthrise photo taken by an Apollo 8 astronaut showing the planet as seen from the moon.

    The two probes, which run on nuclear-powered systems called radioisotope thermoelectric generators (RTGs), kept flying. Our solar system has no clear boundary, but in the 2000s they crossed the “termination shock,” where solar wind particles abruptly slow below the speed of sound due to pressure from the gas and magnetic fields in interstellar space. Then in the 2010s, they breached the heliopause, the boundary between the solar wind and the
    and the interstellar wind.



    With four instruments operating on Voyager 1 and five aboard Voyager 2, they now have a new job: measuring the magnetic field strength, the density of the plasma, and the energy and direction of charged particles in the environment they’re traveling through. “The purpose of the interstellar mission is to measure the sun’s effects as we go further and further from Earth. We’re trying to find out how the sun’s heliosphere interacts with interstellar space,” says Suzanne Dodd, project manager of the Voyager interstellar mission at JPL. Voyager 1 is currently 14.6 billion miles from home, and Voyager 2 is 12.1 billion miles away, but for perspective, the nearest star is some 25 trillion miles away. (NASA maintains a tracker of their journeys.) It’s a remarkable coda for their mission, decades after the probes completed their main goals.
     
    CAC likes this.
  10. OpanaPointer

    OpanaPointer I Point at Opana Staff Member Patron   WW2|ORG Editor

    Joined:
    Jun 5, 2008
    Messages:
    15,907
    Likes Received:
    4,935
    [​IMG]

    An Iridescent Pileus Cloud over China
    Image Credit & Copyright: Jiaqi Sun (孙嘉琪)

    Explanation: Yes, but how many dark clouds have a multicolored lining? Pictured, behind this darker cloud, is a pileus iridescent cloud, a group of water droplets that have a uniformly similar size and so together diffract different colors of sunlight by different amounts. The featured image was taken last month in Pu'er, Yunnan Province, China. Also captured were unusual cloud ripples above the pileus cloud. The formation of a rare pileus cloud capping a common cumulus cloud is an indication that the lower cloud is expanding upward and might well develop into a storm.



    Explore Your Universe: Random APOD Generator
    Tomorrow's picture: big red
     
    GRW likes this.
  11. OpanaPointer

    OpanaPointer I Point at Opana Staff Member Patron   WW2|ORG Editor

    Joined:
    Jun 5, 2008
    Messages:
    15,907
    Likes Received:
    4,935
    Back in the '70s I'd just glance at that thing, then return to watching the letters on the pages of the book I was reading dance and march in formation.
     
  12. CAC

    CAC Ace of Spades

    Joined:
    Dec 1, 2010
    Messages:
    8,186
    Likes Received:
    2,296



    Yeah I’d be ducking for cover if I saw that…
     
  13. OpanaPointer

    OpanaPointer I Point at Opana Staff Member Patron   WW2|ORG Editor

    Joined:
    Jun 5, 2008
    Messages:
    15,907
    Likes Received:
    4,935
  14. GRW

    GRW Pillboxologist WW2|ORG Editor

    Joined:
    Oct 26, 2003
    Messages:
    20,369
    Likes Received:
    2,785
    Location:
    Stirling, Scotland
    "The European Space Agency's Solar Orbiter spacecraft has captured the reversal of the Sun's magnetic field on camera for the first time.
    These reversals, known as magnetic switchbacks, have previously been hypothesised, but until now have not been observed directly.
    The new observation provides a full view of the structure and confirms that magnetic switchbacks have an S-shaped character.
    ESA hopes the footage will help to unravel the mystery of how their physical formation mechanism might help accelerate solar winds."
    www.dailymail.co.uk/sciencetech/article-11210753/ESAs-Solar-Orbiter-records-mysterious-magnetic-switchback.html
     
  15. OpanaPointer

    OpanaPointer I Point at Opana Staff Member Patron   WW2|ORG Editor

    Joined:
    Jun 5, 2008
    Messages:
    15,907
    Likes Received:
    4,935
    This is very similar to the town I lived in, Motta San Anastasia, Provincia Catania, Sicilia, Italia.

    [​IMG]

    APOD pix.
     
  16. Biak

    Biak Adjutant Staff Member Patron  

    Joined:
    Nov 15, 2009
    Messages:
    7,800
    Likes Received:
    1,833
    Neptune in a different light

    upload_2022-9-21_9-17-0.png

    Webb’s Near-Infrared Camera (NIRCam) images objects in the near-infrared range from 0.6 to 5 microns, so Neptune does not appear blue to Webb. In fact, the methane gas so strongly absorbs red and infrared light that the planet is quite dark at these near-infrared wavelengths, except where high-altitude clouds are present. Such methane-ice clouds are prominent as bright streaks and spots, which reflect sunlight before it is absorbed by methane gas.
    Credits: NASA, ESA, CSA, STScI
     
  17. OpanaPointer

    OpanaPointer I Point at Opana Staff Member Patron   WW2|ORG Editor

    Joined:
    Jun 5, 2008
    Messages:
    15,907
    Likes Received:
    4,935


    DART: Impact on Asteroid Dimorphos
    Video Credit: NASA, JHUAPL, DART

    Explanation: Could humanity deflect an asteroid headed for Earth? Yes. Deadly impacts from large asteroids have happened before in Earth's past, sometimes causing mass extinctions of life. To help protect our Earth from some potential future impacts, NASA tested a new planetary defense mechanism yesterday by crashing the robotic Double Asteroid Redirection Test (DART) spacecraft into Dimorphos, a small asteroid spanning about 170-meters across. As shown in the featured video, the impact was a success. Ideally, if impacted early enough, even the kick from a small spacecraft can deflect a large asteroid enough to miss the Earth. In the video, DART is seen in a time-lapse video first passing larger Didymos, on the left, and then approaching the smaller Dimorphos. Although the video ends abruptly with DART's crash, observations monitoring the changed orbit of Dimorphos -- from spacecraft and telescopes around the world -- have just begun.
     
  18. Biak

    Biak Adjutant Staff Member Patron  

    Joined:
    Nov 15, 2009
    Messages:
    7,800
    Likes Received:
    1,833
    That was some serious deflection shooting right there !
     
  19. CAC

    CAC Ace of Spades

    Joined:
    Dec 1, 2010
    Messages:
    8,186
    Likes Received:
    2,296
  20. Biak

    Biak Adjutant Staff Member Patron  

    Joined:
    Nov 15, 2009
    Messages:
    7,800
    Likes Received:
    1,833
    Just imagine looking at the night sky if we lived in one of these Galaxies,

    upload_2022-10-5_19-45-53.png

    Consider the image of Stephan's Quintet, in which four galaxies are locked in a complex gravitational dance while a fifth galaxy is a distant observer of this cosmic choreography.
    The JWST image of these galaxies showed features that astronomers had never seen before, particularly results of their interactions like tails of gas and bursts of intense star formation. When combined with data from Chandra and NASA's retired Spitzer Space Telescope, the observations of Stephan's Quintet revealed a hitherto unseen shock wave heating gas to tens of millions of degrees on any scale. This shock wave is created by one of the galaxies weaving through the others at around 2 million mph (3 million kph).
     

Share This Page