GREENBELT, Md., Jan. 8 (UPI) -- Some 8,000 light-years from the sun, there lies Eta Carinae, a massive, unstable stellar system featuring two stars locked in a violent orbital tussle. It's the most luminous star system within 10,000 light-years of our solar system.
This week, NASA unveiled new imagery of the two-star struggle, allowing viewers to explore Eta Carinae in 3-D, from the inside out.
For reasons astronomers still don't understand, Eta Carinae exploded twice during the 1800s. Its eruption in the 1840s briefly made it the second brightest star in the night sky. The explosion birthed the Homunculus Nebula in which the two orbiting stars are enclosed -- the nebula is the scattering of cosmic material that appears spewed outward in all directions. The two stars and the immediate nebula are part of the much larger Carina Nebula.
What has long fascinated scientists about Eta Carinae are the violent interactions between the two stars.
"It's an erratic stellar monster," astronomer Michael Corcoran of NASA's Goddard Space Flight Center told attendees at the American Astronomical Society meeting in Seattle on Wednesday.
Every 5.5 years the two stars arrive at their closest point to each other -- roughly the distance between the sun and Mars. As they approach that point, or their periastron, they begin to increasingly emit X-rays until suddenly (just past periastron) they don't.
New in-depth X-ray data has helped scientists build 3-D imagery of the stars' interactions and better understand how the differing solar winds -- the primary star's wind blows much slower than the winds of its ultra-hot companion -- affect the binary system's electromagnetic output.
"We think these structures are real and that they form as a result of instabilities in the flow in the months around closest approach," researcher Thomas Madura said of the new simulated interactions created by a 3-D printer. "I wanted to make 3-D prints of the simulations to better visualize them, which turned out to be far more successful than I ever imagined."
While the two stars continue to lose mass, there's no indication their regular fireworks display is losing steam; neither of the stars are expected to dissipate any time soon.
"The 2014 emission is nearly identical to what we saw at the previous periastron in 2009," Goddard researcher Mairan Teodoro said, "which suggests the primary wind has been constant and that the companion's wind is responsible for the X-ray flares."