AstroTalk Episode June 8, 2017

Blobs of X-Ray Emissions Imaged by the Chandra X-Ray Observatory

3:10pm - 3:25pm

Astronomers using Chandra are studying a MIra type star , a type of symbiotic star, which co-exists with another star. R Aquair, or R Aqr, is 710 light years from Earth, and is emitting blobs of X-ray emissions. It is a cool, red giant star (a Mira variable star), orbiting a dense white dwarf. The red giant is pulsating and its brightness can change by a factor of 250. The surface temperature of the white dwarf is 20,000 degrees, while the red giant measures in at 3,000. The 2 stars are comparable in mass, but since the WD is much more compact, it is much more dense. This means that is has a stronger gravitational tug, and it is therefore pulling off gas from the red giant, and onto itself. This has resulted in nova explosions on the WD in 1073 and 1773. NASA scientists now believe NOVA explosions occurred from the WD in the early 2000s, and in the 1950s and 1980s. With the NOVA, matter is ejected from the WD at 10 million miles per hour. With this a ring of ejecta is seen.The NOVA explosions are thought to give rise to 2 jets of X-ray emissions that stream away from the pair of stars at 14. & 1.9 millions miles per hour. With these observations, scientists are trying to understand the volatile relationships that can occur between pairs of stars like these.