Scientists first found a special kind of neutron star outside the Milky Way, using data from the Chandra X-ray Observatory (NASA) and the Very Large Telescope (ESO, Chile)
Neutron stars are ultradented cores of massive stars, collapsing and undergoing a supernova explosion. The newly identified object is a rare species with a low magnetic field and satellite. The neutron star is located in supernova remnants 1E 0102.2-7219 (E0102 for short), residing in the Small Magellanic Cloud (200,000 light-years distant from us).
New shot E0102 allows astronomers to learn new details about the object, found more than 30 years ago. In the image, Chandra X-rays are blue and purple, and visible light data from the Very Large Telescope (VLT) is bright red. For more information, the Hubble Space Telescope is colored dark red and green.
Oxygen-rich supernova remnants, like E0102, are important for understanding how massive stars manage to drain lighter elements into heavy ones before they explode. The remains have material thrown from the inside of a dead star. This garbage (green threadlike structure) is observed today at a speed of millions of miles per hour. Chandra’s observation shows that a large ring-shaped structure in X-ray radiation associated with a supernova explosion wave dominates the supernova remnant. New data from MUSE showed less gas (in bright red), which grows slower than the blast wave. In the center of the ring is a blue point source of x-rays.
Quick look at E0102
Combined information Chandra and MUSE suggest that this source is an isolated neutron star created by a supernova explosion about 2000 years ago. The signature of the X-ray energy (spectrum) is very similar to the signature of neutron stars located in the center of two other known oxygen-rich supernova remnants: Cassiopea A and Korma A.
The lack of evidence for extended radio emission or pulsed x-rays indicates that the researchers found x-rays from the hot surface of an isolated neutron star with small magnetic fields. In our galaxy about 10 similar objects are found. But this is the first fixation outside the Milky Way. How did this star appear in its present position? And why is it offset from the center of the circular shell? Perhaps a supernova explosion occurred near the middle of the remainder, but a neutron star was thrown from a place in an asymmetric explosion at a high speed of 2 million miles per hour. True, this scenario is difficult to explain why the neutron star today is so neatly surrounded by a gas ring.
There is a second explanation. The neutron star moves slowly, and its current position roughly corresponds to a supernova explosion. Then the material in the optical ring may have been thrown out during the explosion by a supernova or with a doomed predecessor star several thousand years ago. But this option also faces a problem, because the place of the explosion will be far from the center of the remainder.
Future observations of E0102 on X-ray, optical and radio waves should help astronomers solve this amazing puzzle created by a single neutron star.