The most luminous and massive stellar system within 10,000 light-years from Earth, Eta Carinae is accelerating cosmic ray particles at high speeds and perhaps some of these rays are reaching Earth.
Also, NASA's Fermi Gamma-ray Space telescope had been previously detecting gamma rays that contained X-rays with greater energy compared to other similarly detected gamma rays.
The radiation, which is believed to contain energy greater than one billion electron volts, is riding intergalactic winds, quickly making its way through the great expanse.
Because they're electrically charged and they change their course under the influence of magnetic fields, the cosmic rays that reach Earth are hard to trace back to their origins. But because the paths of cosmic rays are scrambled by magnetic fields, tracing their origins is quite hard. This binary star system is located some 7,500 light-years away, in the Carina constellation, and is made up of two enormous stars with 90 and 30 times the mass of our sun. These stars have eccentric orbits that bring them unusually close to each other every 5.5 years. "Where these winds clash changes during the orbital cycle, which produces a periodic signal in low-energy X-rays", explains study co-author Michael Corcoran, an astrophysicist at Goddard.
New observations by NASA's NuSTAR space telescope suggest the super luminous star system Eta Carinae produces cosmic rays, some of which likely reach Earth. These X-rays have been observed with both the Fermi Gamma-ray Space Telescope and NuSTAR.
To bridge the gap between low-energy X-ray monitoring and Fermi observations, Hamaguchi and his colleagues turned to NuSTAR.
Eta Carinae's low-energy, or soft, X-rays come from gas at the interface of the colliding stellar winds, where temperatures exceed 70 million degrees Fahrenheit (40 million degrees Celsius).
Both of the stars are constantly puking out charged particles at extremely high speeds, with the larger star's wind slamming into that of the smaller star, creating massive waves of energy that is being blown out into space. According to the readings, some of those X-ray emissions were about 30,000 electron Volts, which is huge given the fact that the visible light' energy is between 2 and 3 electron Volts.
Some of these extremely fast particles crash into starlight, which boosts their light's energy, turning them into X-rays and even gamma rays, reveals the new study.
Focused NuSTAR observations show that the colliding winds of the massive binary eta Carinae accelerate particles to very high energies, adding to the cosmic ray flux of the Galaxy. The best explanation for hard X-rays is electrons accelerated in violent shock waves along the boundary of the colliding stellar winds, suggesting that these stellar winds are more dramatic than expected. However, it is only until now that scientists were sure that these energies are reaching the Earth in the form of cosmic rays. Astronomers earlier observed that these unique gamma rays were coming from the direction of Eta Carinae. "But until NuSTAR was able to pinpoint the radiation, show it comes from the binary and study its properties in detail, the origin was mysterious". The spacecraft was built by Orbital Sciences Corp., Dulles, Virginia. ASI provides the mission's ground station and a mirror archive.