Chandra Release - June 6, 2002

Visual Description: 1E 1207.4-5209

1E 1207.4-5209 is a neutron star, which is depicted in an illustration at the upper left, and with an inset of an X-ray spectrum from Chandra at bottom right. The spectrum is a simple graph with two lines that provides information about the energy released by the neutron star. The neutron star appears to be spinning or rotating rapidly, which contributes to the release of energy. The shape of the neutron star is reminiscent of a sphere, but it is much smaller and denser than a typical planet or star. It is one of the most dense objects in the universe, with a mass comparable to that of the sun, but occupying only a tiny fraction of its volume. An artist's concept illustrates the neutron star with a polar hot spot and a strong magnetic field (shown with looping purple lines). The graph in the box to the lower right of the star shows expected (dashed blue line) and observed (solid green line) spectra of the X-radiation from the hot spot. The dips in the observed spectrum are absorption features due to gas in the atmosphere of the neutron star. The neutron star 1E 1207.4-5209 is about 7,000 light years from Earth.