Imagine the Universe!


Part 1 -- A Wolf-Rayet star in its final hours. Wolf-Rayet stars are extremely massive bluish stars, containing the mass of 10 to 15 suns. The blue-white color of the star indicates that its surface temperature is approximately 50,000 C. Surrounding the star are wisps of gas that have recently been shed from the outer atmosphere.

Part 2 -- Diving through the surface of the Wolf-Rayet star, we come to the stellar core, about 10 percent the size of the whole star. We see shells of iron, oxygen, and carbon in the core, the ash of nuclear burning. This star is now out of fuel. Lacking energy to support its own mass, the core collapses and a black hole forms, pulling in matter. Yet a jet of material escapes through the polar regions, perhaps powered by renewed fusion and the spin of the black hole. The animation is nearly in real-time.

Part 3 -- The jet of material formed in the stellar core pierces through the star's surface, traveling at near light speed.

Part 4 -- The Wolf-Rayet star and its newly-formed jets from a more distant perspective. We see that internal collisions of the jet material with itself are releasing energy -- photons that will eventually be observed as gamma-rays by satellites in Earth orbit when the beam is pointed in our direction.

Imagine the Universe is a service of the High Energy Astrophysics Science Archive Research Center (HEASARC), Dr. Alan Smale (Director), within the Astrophysics Science Division (ASD) at NASA's Goddard Space Flight Center.

The Imagine Team
Acting Project Leader: Dr. Barbara Mattson
All material on this site has been created and updated between 1997-2012.

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