Preliminary studies suggest it may have been caused by the collision of two neutron stars, causing a massive nuclear explosion, and subsequently destroying both objects.
In a curious twist however, during early March radio astronomers at the University of Bürgerweldt detected significant radio noise emanating from a source very close to the coordinates of the gamma ray burster which were consistent with an object being ejected at high speed, and in the general direction of our Solar System.
In view of the extremely low density of atoms throughout interstellar space it was computed that any object capable of generating the semblance of an ionisation trail had to be moving at an extraordinarily high velocity, in fact approaching or even exceeding 98.5% of the speed of light in order to impact with a sufficient number of atoms.
This object was tracked and shown to be passing so close to the Sun that any asteroid of similar apparent size should have been drawn in by the Sun's gravity and destroyed.
Instead however it performed a “sling-shot” manoeuvre and passed around the Sun at such a high velocity that it is computed that it will totally escape the solar system and head off in the direction of Regulus.
This could happen only to an object of such a high density that the kinetic energy it had could only be explained by the object being of truly enormous density, consistent with it being a detached remnant of a neutron star.
This finding has disturbing implications, as it seems that at least some gamma ray bursters may routinely eject such “cosmic bullets” at random into the surrounding interstellar medium.
The bad news is that being of such high mass and density, their capacity to cause great damage is enormous.
The good news is that at the estimated velocity of such an object, the chances of them being perturbed sufficiently by the gravitational attraction of the Earth and Sun so as to impact on our planet are small.
It is however conceivable that over billions of years a few have come in at a trajectory sufficient to have been captured by the Sun's gravity and become unusual members of the asteroid belt - unusual in the sense that they would have highly elliptical orbits taking them far from the Sun and subsequently taking scores of thousands of years to complete one revolution.
Surveys of Near Earth Asteroids have now become a routine event.
The catch however is that such highly dense objects, when moving close to the Sun, would have such a high velocity as to leave little lead time for computation of orbits or consideration of preventative or mitigation measures.
The evidence is being examined to determine if the object recently impacting the Moon and reported earlier in this journal was in fact a neutron star remnant. (See “Asteroid Impact Shifts Moon’s Axial Tilt” on page 2 for further information)
Meantime, asteroids of unusually high velocities will be given special attention to determine whether their orbits are consistent with them being of higher than normal density.