Eta Carinae: New view of doomed star

Discussion in 'OFF-Topic / Misc.' started by syscom3, Jun 23, 2007.

  1. syscom3

    syscom3 Pacific Historian

    Joined:
    Jun 4, 2005
    Messages:
    12,631
    Likes Received:
    309
    Trophy Points:
    83
    Gender:
    Male
    Location:
    Orange County, CA
    Eta Carinae is a mysterious, extremely bright and unstable star located a mere stone's throw - astronomically speaking - from Earth at a distance of only about 7,500 light years. The star is thought to be consuming its nuclear fuel at an incredible rate, while quickly drawing closer to its ultimate explosive demise.

    When Eta Carinae does explode, it will be a spectacular fireworks display seen from Earth, perhaps rivaling the moon in brilliance. Its fate has been foreshadowed by the recent discovery of SN2006gy, a supernova in a nearby galaxy that was the brightest stellar explosion ever seen. The erratic behavior of the star that later exploded as SN2006gy suggests that Eta Carinae may explode at any time.

    Eta Carinae, a star between 100 and 150 times more massive than the Sun, is near a point of unstable equilibrium where the star's gravity is almost balanced by the outward pressure of the intense radiation generated in the nuclear furnace. This means that slight perturbations of the star might cause enormous ejections of matter from its surface.

    In the 1840s, Eta Carinae had a massive eruption by ejecting more than 10 times the mass of the sun, to briefly become the second brightest star in the sky. This explosion would have torn most other stars to pieces but somehow Eta Carinae survived.

    The latest composite image shows the remnants of that titanic event with new data from NASA's Chandra X-ray Observatory and the Hubble Space Telescope. The blue regions show the cool optical emission, detected by Hubble, from the dust and gas thrown off the star. This debris forms a bipolar shell around the star, which lies near the brightest point of the optical emission. This bipolar shell is itself surrounded by a ragged cloud of fainter material. An unusual jet points from the star to the upper left.

    Chandra's data, depicted in orange and yellow, shows the X-ray emission produced as material thrown off Eta Carinae rams into nearby gas and dust, heating gas to temperatures in excess of a million degrees.

    This hot shroud extends far beyond the cooler, optical nebula and represents the outer edge of the interaction region. The X-ray observations show that the ejected outer material is enriched by complex atoms, especially nitrogen, cooked inside the star's nuclear furnace and dredged up onto the stellar surface.

    The Chandra observations also show that the inner optical nebula glows faintly due to X-ray reflection. The X-rays reflected by the optical nebula come from very close to the star itself; these X-rays are generated by the high-speed collision of wind flowing from Eta Carinae's surface (moving at about 1 million miles per hour) with the wind of the companion star (which is about five times faster).

    The companion is not directly visible in these images, but variability in X-rays in the regions close to the star signals the star's presence. Astronomers don't know exactly what role the companion has played in the evolution of Eta Carinae, or what role it will play in its future.

    Spaceflight Now | Breaking News | Eta Carinae: New view of doomed star
     

    Attached Files:

  2. timshatz

    timshatz Active Member

    Joined:
    Mar 29, 2006
    Messages:
    4,441
    Likes Received:
    3
    Trophy Points:
    38
    Occupation:
    MGR
    Location:
    Phila, Pa
    Cool. Would be great it it went "pop" in our lifetimes. As long as the burst of radiation coming from it doesn't fry us. With that provision, it would be spectacular sight.

    I saw Haley's Comet back in '86 (?). It was kinda ho-hum. Not very bright. Would be cool to see this.
     
  3. syscom3

    syscom3 Pacific Historian

    Joined:
    Jun 4, 2005
    Messages:
    12,631
    Likes Received:
    309
    Trophy Points:
    83
    Gender:
    Male
    Location:
    Orange County, CA
    Heres another view of whats happening inside this nebula.

    ABOUT THIS IMAGE:

    In celebration of the 17th anniversary of the launch and deployment of NASA's Hubble Space Telescope, a team of astronomers is releasing one of the largest panoramic images ever taken with Hubble's cameras. It is a 50-light-year-wide view of the central region of the Carina Nebula where a maelstrom of star birth - and death - is taking place.

    Hubble's view of the nebula shows star birth in a new level of detail. The fantasy-like landscape of the nebula is sculpted by the action of outflowing winds and scorching ultraviolet radiation from the monster stars that inhabit this inferno. In the process, these stars are shredding the surrounding material that is the last vestige of the giant cloud from which the stars were born.

    The immense nebula contains at least a dozen brilliant stars that are roughly estimated to be at least 50 to 100 times the mass of our Sun. The most unique and opulent inhabitant is the star Eta Carinae, at far left. Eta Carinae is in the final stages of its brief and eruptive lifespan, as evidenced by two billowing lobes of gas and dust that presage its upcoming explosion as a titanic supernova.

    The fireworks in the Carina region started three million years ago when the nebula's first generation of newborn stars condensed and ignited in the middle of a huge cloud of cold molecular hydrogen. Radiation from these stars carved out an expanding bubble of hot gas. The island-like clumps of dark clouds scattered across the nebula are nodules of dust and gas that are resisting being eaten away by photoionization.

    The hurricane blast of stellar winds and blistering ultraviolet radiation within the cavity is now compressing the surrounding walls of cold hydrogen. This is triggering a second stage of new star formation.

    Our Sun and our solar system may have been born inside such a cosmic crucible 4.6 billion years ago. In looking at the Carina Nebula we are seeing the genesis of star making as it commonly occurs along the dense spiral arms of a galaxy.

    The immense nebula is an estimated 7,500 light-years away in the southern constellation Carina the Keel (of the old southern constellation Argo Navis, the ship of Jason and the Argonauts, from Greek mythology).

    This image is a mosaic of the Carina Nebula assembled from 48 frames taken with Hubble Space Telescope's Advanced Camera for Surveys. The Hubble images were taken in the light of neutral hydrogen. Color information was added with data taken at the Cerro Tololo Inter-American Observatory in Chile. Red corresponds to sulfur, green to hydrogen, and blue to oxygen emission.
     

    Attached Files:

  4. DerAdlerIstGelandet

    DerAdlerIstGelandet Der Crew Chief
    Staff Member Moderator

    Joined:
    Nov 8, 2004
    Messages:
    41,775
    Likes Received:
    687
    Trophy Points:
    113
    Occupation:
    A&P - Aircraft Technician
    Location:
    USA/Germany
    Surely would be neat to see.
     
Loading...

Share This Page