14
POPSQuiet Explosion: Object Intermediate Between Normal Supernovae And Gamma-ray Bursts Found Stars that were at birth more massive than about 8 times the mass of our Sun end their relatively short life in a cosmic, cataclysmic firework lighting up the Universe. The outcome is the formation of the densest objects that exist, neutron stars and black holes. When exploding, some of the most massive stars emit a short cry of agony, in the form of a burst of very energetic light, X- or gamma-rays.
11
POPSA Quark Star? Super-luminous Stellar Explosion Observed Quarks are the fundamental components of protons and neutrons, which make up the nucleus of atoms. The most dense objects known to exist today are neutron stars--stars composed entirely of tightly packed neutrons. A typical neutron star is some 16 miles across, yet has a mass one and a half times the mass of our Sun. The question is, is a neutron star indeed the most dense object that exists? It is thought that if the neutrons are too tightly packed--if what scientists consider a neutron star is too dense--the resulting instability may lead to a further collapse, resulting in a second explosion and the creation of a quark star. The energy that powers that second explosion comes from neutrons breaking down into their component parts: quarks.
5
POPSStellar Time Bomb - Tick, Tick If it’s a binary, then both stars are likely to end their lives as supernovae -- explosions that blast the stars to bits. Each will leave behind a neutron star or a black hole. A single star would probably explode, too, but it could form one of the most powerful blasts in the universe -- a gamma-ray burst.
3
POPSPocket-Sized Powerhouse "Illustration of Circinus X-1 This artist's illustration depicts the jet of relativistic particles blasting out of Circinus X-1, a system where a neutron star is in orbit with a star several times the mass of the Sun. The neutron star, an extremely dense remnant of an exploded star consisting of tightly packed neutrons, is seen as the sphere at the center of the disk. The powerful gravity of the neutron star pulls material from the companion star (shown as the blue star in the background) into a so-called accretion disk surrounding it. Through a process that is not fully understood, a jet of material moving at nearly the speed of light is generated. A high percentage of the energy available from material falling toward the neutron star is converted into powering this jet. " ...http://chandra.harvard.edu/photo/2007/cirx1/more.html#ill_xrayBinaryJets