Pair of colliding stars spill radioactive molecules into space

When two Sun-like stars collide, the result can be a spectacular explosion and the formation of an entirely new star. One such event was seen from Earth in 1670. It appeared to observers as a bright, red "new star." Though initially visible with the naked eye, this burst of cosmic light quickly faded and now requires powerful telescopes to see the remains of this merger: a dim central star surrounded by a halo of glowing material flowing away from it.

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Credit: NRAO/AUI/NSF; S. Dagnello

Artist impression of the collision of two stars, like the ones that formed CK Vul. The inset illustrates the inner structure of one red giant before the merger. A thin layer of 26-aluminum (brown) surrounds a helium core. An extended convective envelope (not to scale), which forms the outermost layer of the star, can mix material from inside the star to the surface, but it never reaches deep enough to dredge 26-aluminum up to the surface. Only a collision with another star can disperse 26-aluminum

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Credit: ALMA (ESO/NAOJ/NRAO), T. Kami?ski & M. Hajduk; Gemini, NOAO/AURA/NSF; NRAO/AUI/NSF, B. Saxton

Composite image of CK Vul, the remains of a double-star collision. This impact launched radioactive molecules into space, as seen in the orange double-lobe structure at the center. This is an ALMA image of 27-aluminum monofluoride, but the rare isotopic version of AlF resides in the same region. The red, diffuse image is an ALMA image of the more extended dust in the region. The blue is optical hydrogen emission as seen by the Gemini observatory.

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Armed with state-of-the-art supercomputer models, scientists have shown that colliding neutron stars can produce the energetic jet required for a gamma-ray burst. Earlier simulations demonstrated that mergers could make black holes. Others had shown that the high-speed particle jets needed to make a gamma-ray burst would continue if placed in the swirling wreckage of a recent merger.

Now, the simulations reveal the middle step of the process--how the merging stars' magnetic field organizes itself into outwardly directed components capable of forming a jet.

On August 17, researchers around the world detected the signals from a neutron star collision that took place 130 million years ago.

Dragon wrote:

On August 17, researchers around the world detected the signals from a neutron star collision that took place 130 million years ago.

We are so lucky to be able to do this, how amazing after 130 million years