Located 7,500 light years from Earth, Eta Carinae is made up of two colossal stars that orbit each other: the mass of the largest is 90 times that of the Sun and its brightness exceeds five million times that of our star; the smallest has about 30 solar masses and “only” emits a million times more light than the star that gives us life.
This galactic monster has been surprising astronomers since the mid-nineteenth century, when the light that produced a huge eruption emerged from its surface reached our planet. The cataclysm, the reasons for which are unknown to scientists, launched into space a quantity of gas and dust equivalent to ten times the mass of the Sun and surrounded Eta Carinae in what we call the Homunculus Nebula.
NASA has just announced the results of a long study that has used data and images from satellites, space telescopes (such as Hubble ) and terrestrial to obtain 3D models that reveal new aspects of the interaction of the two stars that make up this system stellar, the brightest object in a 10,000 light-year radius around Earth.
The two components of this binary celestial body emit powerful flows of ionized gases that shoot out at speeds of more than a million kilometers per hour, surround the two stars and allow us to measure some of their properties. Ted Gull, a NASA astrophysicist who coordinates the research, assures that the new observations will help us understand “the state and complex structure of Eta Carinae, although we have a long way to go to explain its past eruptions and predict its future.”
Astronomers thought that Eta Carinae was a unique object, but another team of NASA researchers has found five similar stars: two located in the M83 galaxy, 15 million light-years away; and three others in the galaxies NGC 6946, M101 and M51 respectively, located at distances of between 18 and 26 million light years. These discoveries will shed light on how massive stars form, evolve, and die.
Image: This is how the Hubble Space Telescope captured the Homunculus Nebula surrounding Eta Carinae and is evidence of an ancient eruption of gas and dust. (NASA / ESA)
