Astronomers are relishing in the latest sky spectacle: bigger than our sun, with such an elegant brilliance that is producing 5 million times the intensity of it, Eta Carinae is the main attraction in the American Astronomical Society conference. Having arrived to its 225th meeting, they talk about the latest discoveries of the NASA observatories. Wednesday it has been about Eta Carinae : two stars that orbit each other, of which one is bigger (approximately 90 times bigger than our sun) and the other one smaller.
A normal day for Eta Carinae and its two stars looks a lot like this: they orbit each other and form “stellar winds”, which are formations of gas spread into space. A special moment for the famous duo is when they get really close to each other and form some sort of “Fireworks” that echo through space. This certain fact has been deeply observed into detail by NASA, in their purpose of finding more about brilliant Eta. A shocking interaction happens when the smaller star meets the other one’s dense winds. The collision is spectacular : a six million mile per hour hit by a foreign object, and then decelerating to zero in no time. It’s a veritable show for any passionate scientist. The star encounter generates X-rays that are of an important use for scientists: they can register the orbital period of the formation, that is at a five and a half years.
There is also a blue light that turned heads while referring to Eta Carinae. A team of scientists explore the helium atoms that form the beautiful shade. It has been admired in the sunrise and in the sunset of three orbital periods. The discovery is exquisite : the bigger star’s winds generate the blue color made out of luminous flares, apart from the interaction with the smaller one.
Eta Cariane has been observed from the 19th century, being expected to explode and become a supernova. It erupted twice in 1840, but the reasons are yet unknows.
In order to achieve new discoveries, NASA used three specific methods: supercomputers that make different kind of simulations, 3D printers and space telescopes. All the results have been published online and have had over 100 000 downloads and visualisations.
The magnificent star formation is unfortunately very far away from Earth: it sits in the constellation Carina, 7500 light years away and it is the biggest star formation within 10 000 light years.
Image Source: ISDC