This is the first time that a massive eruption of stellar or also called a mass ejection coronal, has been detected escaping from a star that is not the Sun.
These bursts of plasma and charged particles are well known in the sun, and commonly follow a burst of light called a solar flare. Astronomers had detected flares on other stars, but never a mass ejection coronal, or CMES, until now. The discovery could have implications for the prospects of life on planets of other star systems.
The ejection in question is associated with a flare that was detected 10 years ago, from a giant star called HR 9024 approximately 450 light-years from Earth. The star is about three times larger than the sun and 10 times wider.
The astronomer Costanza Argiroffi of the University of Palermo in Italy and his colleagues found evidence of the outburst of the star using a new method to analyze data taken with the Chandra X-ray Observatory, said Argiroffi in the meeting of Cool Stars 20 the 2 of August.
The team Argiroffi detected material moving up and down a loop of plasma extending from the surface of the star during the flare by measuring the Doppler shift of certain X-rays, the change in the wavelengths of X-rays as the material is approaching or moving away from the Earth. The researchers saw that the more material away from the star after it had stopped the blaze and interpreted the observation as a mass ejection coronal.
Astrophysicist Julian Alvarado-Gomez of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts, and not involved in the study, said in a statement:
People have sought this for a long time, and this is the first time you see this.”
A massive eruption of stellar
The ejection containing approximately 1 trillion trillion grams of material, which is about what they expected the scientists according to the estimates extrapolated from the CME from the sun to bigger stars. But the kinetic energy of the burst, as measured by the speed of the material to escape, was much lower than expected.
The strong magnetic field of the star could have retained the eruption, suggests that Alvarado-Gomez. His group has performed computer simulations that show that a strong magnetic field can sometimes act as a cage that holds a CME tied to the star or slows down the progress of the expulsions that occur.
This could help explain why scientists have not detected a CME from another star above. The strong magnetic fields of stars are associated with more flares, which should cause more ejections, which is why scientists have wondered if it could not detect one.
Such impairment magnetic could be a good news for exoplanets in orbit, if the HR 9024 you have any. In our solar system, the energy and matter released in both the flares as in the CME can wreak havoc on the planets. The Earth is largely protected by its own magnetic field, but Mars does not have as much luck.
While a strong magnetic field could help to keep the planets of a star safe from the ravages of the CME, it could be a double-edged sword, says Alvarado-Gomez.
The bad news is that this energy has to go somewhere, and maybe this is to encourage more flares that are not weakened by the field. Many of the exoplanets are potentially habitable, that astronomers have discovered orbiting very close to stars, prone to eruptions”.
Cynthia Froning, astronomer of the University of Texas at Austin said in a press release:
If such eruptions are accompanied by these emissions of particles to the same speed as they are in the sun are going to be very detrimental to the formation of life and the maintenance of the atmosphere of those planets”.
The scientific study has been published in Astrophysical Journal.