July 1 (UPI) -- The Hubble Space Telescope has captured Eta Carinae's fireworks in red, white and blue, just in time for Independence Day.
Eta Carinae is a binary star system located 7,500 light-years away in the Carina constellation. One of its two stars, which orbit each other, is large, highly unstable and nearing the end of its life. The dynamic stellar duo occasionally produces violent outbursts.
The system's most famous outburst occurred in 1838. In the wake of the eruption, the stars gradually brightened. By 1844, Eta Carinae was the second brightest star in the night sky.
The duo's time on top was short-lived, but the system remains a favorite target for astronomers. The 19th century outburst is still visible in the form of the dumbbell-shaped clouds of gas and dust.
Over the last quarter-century, Hubble has used nearly its entire arsenal of instruments to image the star system and surrounding nebula.
The newest ultraviolet portrait revealed a new luminous magnesium structure hiding between the the two dumbbells, filaments energized by the collisions between the waves of gas and dust ejected by the star system over millions of years.
"We've discovered a large amount of warm gas that was ejected in the Great Eruption but hasn't yet collided with the other material surrounding Eta Carinae," Nathan Smith, an astronomer with the Steward Observatory at the University of Arizona and lead investigator of the Hubble program, said in a news release. "Most of the emission is located where we expected to find an empty cavity. This extra material is fast, and it 'ups the ante' in terms of the total energy of an already powerful stellar blast."
By studying the movement of gas and dust in the nebula, evidence of previous eruptions, scientists hope to unravel the mystery of how the Great Eruption began. Each new ultraviolet image of the star system and surrounding nebula reveals new structural intricacies, details that might help astronomers better understand the dynamics at play inside Eta Carinae.
"We had used Hubble for decades to study Eta Carinae in visible and infrared light, and we thought we had a pretty full account of its ejected debris. But this new ultraviolet-light image looks astonishingly different, revealing gas we did not see in either visible-light or infrared images," Smith said. "We're excited by the prospect that this type of ultraviolet magnesium emission may also expose previously hidden gas in other types of objects that eject material, such as protostars or other dying stars; and only Hubble can take these kinds of pictures."