Astronomers Catch Powerful ‘Zombie Star’ Speeding Through the Milky Way, Have No Idea Where It is From
The Hubble Space Telescope has helped immensely in updating several space phenomena. One of these is the SGR 0501+4516, about which new insights have been published in Astronomy & Astrophysics. The neutron star was first spotted in 2008, but has now been reexamined through data collected by Hubble, which has provided new information.
The study claims that this magnetar is faster than previously believed, and combined with its direction of movement, challenges the theory of its supposed formation, stated Live Science. SGR 0501+4516 has been determined as a magnetar because it is a neutron star with a strong magnetic field. Initially, SGR 0501+4516 was located at a distance of 15,000 light-years from Earth. Through the Hubble Telescope, researchers analyzed its later sightings and concluded that it is traveling at the speed of 110,000 mph (177,000 km/h) through the Milky Way galaxy. This is much more than what was initially estimated.
In 2008, when SGR 0501+4516 was identified as a neutron star, researchers assumed that it was made during a supernova explosion, according to NASA. This is an event where stars explode in such a manner that they collapse to become an ultra-dense neutron star. The theory became stronger due to the fact that the spot where SGR 0501+4516 was initially located had been close to a supernova remnant called HB9.
The data collected through the Hubble Telescope helped the team trace the path taken by the neutron star thousands of years into the past. This route had no other supernova remnants or massive star clusters, which implied that SGR 0501+4516 was possibly not born in supernovae. This finding further indicates that there is a chance that the estimated age of SGR 0501+4516, which is 20,000 years, could be wrong. The magnetar is possibly older or was formed in an unknown way.
The study also puts forward certain theories regarding the formation of SGR 0501+4516. The team believes that this particular magnetar could be formed due to the coming together of two lower-mass neutron stars. Another proposed technique is accretion-induced collapse. In this method, a binary star system containing a white dwarf star is involved. The white dwarf star pulls gas from its companion, and at one point, becomes so big that it can no longer support itself. This situation could either lead to an explosion or result in the formation of a magnetar.
Andrew Levan of Radboud University in the Netherlands and the University of Warwick in the United Kingdom, one of the study's authors, claims that in the aforementioned situation, typically explosion facilitates. But in certain conditions, a magnetar could be formed, and SGR 0501+4516 could possibly be one of those rare occurrences.
If the assertion turns out to be true, then it could become a possible source for mysterious fast radio bursts that have been observed in space for some time by astronomers. These radio bursts are detected from stellar populations that are so old that they cannot have new stars big enough to explode and produce waves. It is possible that a magnetar like SGR 0501+4516, formed by a large white dwarf star, has the power to produce transient events like FBRs. For verification of this theory, more examination is needed.