The Hubble Space Telescope has caught
the most detailed view of the Crab Nebula, revealing the intricate epitaph
of a long-dead star.
The nebula spans a patch of space six light-years across and has proved
an attractive target for professional and amateur astronomers alike. One
light-year is the distance light travels in one year, about 5.8 trillion
miles (9.7 trillion kilometers).
Wispy filaments, primarily of hydrogen, weave through the Crab Nebula,
at the center of which sits a neutron star that spins 30 times per second.
The only fixed remains of the supernova explosion – the rest of the original
star stuff has blown outward – the neutron star acts as a beacon, spitting
twin beams of radiation from its poles as it rotates.
The dense, city-sized object powers the Crab Nebula’s
bluish glow, which is generated by electrons that follow the neutron
star’s magnetic field lines, astronomers said. The elemental composition
of the nebula can be picked apart by color, with blue areas indicating
neutral oxygen, green regions showing singly ionized sulfur and red portions
denoting doubly ionized oxygen, they added.