JOE T. COXWELL --- Science Fiction Author & Astronomical Artist
Original Science Fiction and Space/Astronomical Art
Member Mississippi Writers Guild
Space News and Features
  • Home
    • Joe T. Coxwell -- A Brief Biography
    • Coxwell's Blog
    • Author Sci-Fi Recommendations
    • Author Interview with Sleepytown Press
  • FREE Story Teasers
    • Epsilon Wish Teaser
    • Third Contact Teaser
  • Purchase Book
    • Order On-line from Amazon.com and Others
    • Order a Kindle Download from Amazon.com
    • Order from the Author by Mail
  • Space News
    • Extraterrestrial Life Search >
      • ​Extraterrestrial Life Could Be Purple
      • ​Alien Life Could Thrive on 'Supercritical' CO2 Instead of Water
      • Alien Megastructure -- "Tabby's Star" -- KIC 8462852 >
        • ​Kepler's 'Alien Megastructure' Star Just Got Weirder
        • ​'Alien Megastructure' Star Keeps Getting Stranger
        • 'Alien Megastructure' Star Is at It Again with the Strange Dimming
      • Humans Will Hear from Intelligent Aliens This Century, Physicist Says
      • ​Could Methane on Saturn's Moon Enceladus Be a Sign of Life?
      • Superflare Blasts Proxima b, the Nearest Exoplanet, ​Dimming Hopes of Life
    • Exoplanets >
      • The Largest Alien Planet of TRAPPIST-1 Has an Atmosphere That Evolved Over Eons
      • First Exomoon Found? Neptune-Sized World Possibly Spotted Orbiting Alien Planet
      • ​Ringed, Rocky Alien Planets May Hide in Plain Sight
      • Kepler Space Telescope Discovers ​95 More Alien Planets
      • ​The Alien Planets of TRAPPIST-1 May Be Too Wet for Life
      • ​Exoplanets: Worlds Beyond Our Solar System
      • Current Potentially Habitable Exoplanets
      • That's No Moon? Proposed Exomoon Defies Formation Theories
      • KOI-500: A Crowded Little Solar System
      • Super-Earth HD 40307g in its Habitable Zone
      • New Earth-mass Planet Found in Nearby Alpha Centauri System
      • Super-Earth 55 Cancri e: Not So Earthlike
      • Newfound Alien Planet a Top Contender to Host Life
      • Planets in Multiple Star Systems -- Is Tatooine for Real?
      • Miniature Solar System Discovered
      • A Periodic Table of Exoplanets
      • Known Types of Alien Planets
      • How Planets in Alien Solar Systems Stack Up
      • Earth-sized Planets Discovered
      • Alien Planet HD 85512 b Holds Possibility of Life
    • Mars Exploration >
      • ​'Mars Ain't Gonna Be Easy': What Apollo 17 Leaders Are Saying About Future Space Exploration
      • The Curiosity Rover Just Drilled into a Rock on Mars for 1st Time Since 2016
      • Curiosity Mars Rover -- Image Gallery
      • Humans on Mars By 2039 -- The Long Delay is Mostly Lack of Political Will
      • Invasion of Mars: Landings and Crashes
    • US Space Program >
      • Pluto's Biggest Moon Could Give an Orbiter an (Almost) Free Ride
      • New Horizons Pluto Photo Gallery >
        • Pluto May Have a Gooey Carbon Layer Beneath Its Crust
      • Space Launch System: NASA's Giant Rocket Explained
      • NASA's New Multi-Purpose Crew Vehicle
    • Private Spaceflight Developments >
      • SpaceX's Dragon Capsule & Falcon-9 Booster
      • SpaceX Nails the Barge Landing!
      • Boeing's CST-100 Spacecraft
      • Sierra Nevada's Dream Chaser Spaceplane
      • Blue Origins >
        • Blue Origin's New Glenn Booster
    • The Solar System >
      • The Sun
      • Mercury
      • Venus >
        • NASA Wants to Send Humans to Venus, to Live in Airships Floating on Clouds
      • Earth's Moon
      • Mars
      • Asteroids / Vesta / Ceres >
        • Asteroid Sampling MIssion
      • Jupiter
      • Saturn / Titan
      • Uranus
      • Neptune
      • Pluto / Eris / Kuiper Belt Objects
  • Space Art & More
    • New or Recent Artwork
    • Space Art Gallery
    • Space Art Slideshow
  • Links & Contact Info
    • Author Contact
    • Links

'Alien Megastructure' Star Is at It Again with the Strange Dimming

Picture
By Calla Cofield, Space.com Staff Writer | May 19, 2017 04:15pm ET
 
      The perplexing cosmic object known as "Boyajian's star" is once again exhibiting a mysterious pattern of dimming and brightening that scientists have tried to explain with hypotheses ranging from swarms of comets to alien megastructures.

      Today (May 19), an urgent call went out to scientists around the world to turn as many telescopes as possible toward the star, to try and crack the mystery of its behavior.   "At about 4 a.m. this morning I got a phone call … that Fairborn [Observatory] in Arizona had confirmed that the star was 3 percent dimmer than it normally is," Jason Wright, an associate professor of astronomy at Pennsylvania State University, who is managing a study of Boyajian's star, said during a live webcast today at 2 p.m. EDT (1800 GMT). "That is enough that we are absolutely confident that this is no statistical fluke. We've now got it confirmed at multiple observatories, I think."

     Star KIC 8462852, or Boyajian's star (also nicknamed "Tabby's star," for astronomer Tabetha Boyajian, who led the team that first detected the star's fluctuations), has demonstrated an irregular cycle of growing dimmer and then returning to its previous brightness. These changes were first spotted in September 2015 using NASA's Kepler Space Telescope, which was built to observe these kinds of dips in a star's brightness, because they can be caused by a planet moving in front of the star as seen from Earth.

      But the brightness changes exhibited by Boyajian don't show the kind of regularity that is typical of a planet's orbit around its star, and scientists can't see how the changes could be explained by a system of planets.   Scientists have hypothesized that the changes could be due to a swarm of comets passing in front of the star, that they're the result of strong magnetic activity, or that it's some massive structure built by aliens. But no leading hypothesis has emerged, so scientists have been eager to capture a highly detailed picture of the light coming from the star during one of these dimming periods. This detailed view is what scientists typically call an object spectra. It can reveal, for example, the specific chemical elements that are in a gas. It can also tell scientists if an object is moving toward or away from the observer.
 
      "Whatever's causing the star to get dimmer will leave a spectral fingerprint behind," Wright said during the webcast, which took place in the Breakthrough Listen laboratory  at the University of California, Berkeley. "So if there is a lot of dust between us and the star … it will block more blue light than red light. If there is gas in that dust, that gas should absorb very specific wavelengths and we should be able to see that. And so, we've been eager to see one of these changes in one of these dips of the star so we can take some spectra."
But the scientists couldn't predict when the next dimming event would occur or how long it will last. (Dips detected by Kepler lasted for between two and seven days, according to Wright.) Professional-grade telescopes typically schedule observing time weeks or months in advance, so Wright and his colleagues knew their observations would have to come at the behest of colleagues who were already using the telescopes for other projects.

      "We need to have a network of people around the world that are ready to jump on [and observe it]," Wright said. "Fortunately, Tabby's star is not too faint and so there are a lot of observers and telescopes … that have graciously agreed to take some time out of their science to grab a spectrum for us [tonight]."

      Wright said the call had gone out to amateur as well as professional astronomers to observe Boyajian's star during this dimming period. The largest and most powerful telescopes that will heed the call are the twin 10-meter telescopes at the W.H. Keck Observatory in Hawaii. The team is working to gain observing time on at least three other large telescopes on the U.S., according to Wright.
 
      The Breakthrough Listen initiative, which searches for signs of intelligent life in the universe, has also taken an interest in the star and will be observing it with the Automated Planet Finder telescope at Lick Observatory in California, according to Andrew Siemion, director or the Berkeley SETI Research Center, said in the webcast.

      "It's Super Bowl Sunday," Siemion said of the atmosphere at the during the webcast. "There's a palpable tension."   Breakthrough and the Berkeley center are now trying to get some observing time on the Green Bank radio telescope in West Virginia, according to Siemion. 
Boyajian was the astronomer at Yale University who led the team that initially spotted the star's brightness fluctuations. It was Boyajian who called Wright at 4 a.m. to confirm that the star is dimming.
​
Follow Calla Cofield @callacofield.Follow us @Spacedotcom, Facebook and Google+. Original article on Space.com.
​

Picture
Light curves showing the periodic dimming of KIC 8462852 (Tabby's Star). A small, single dip in stellar output would represent an orbiting exoplanet, but an atypical series of very large dips are very difficult to reconcile with any known kind of astronomical object.
Picture
Artist's conception of a Dyson Sphere under construction by an advanced alien species. Could something like this account for the unusual light curves present in the Kepler data?
Powered by Create your own unique website with customizable templates.