Extreme Sun and Stars

When Neutron Stars Collide. Photograph by D. Link/M. Koppitz/L. Rezolla/AEI/ZIB. Stellar smash-ups come in all flavors. When exotic neutron stars collide, as in this computer simulation, the cataclysm creates both a black hole and heavy elements, notably gold, as a consequence. (Read “Sun Struck” in National Geographic magazine.)

Collapsed stars, neutron stars weigh about 1.5 times as much as the sun. All that mass ends up tucked into a sphere just 12 miles (20 kilometers) wide. 

They are made of neutrons, subatomic particles normally hidden in the center of atoms. The intense gravity of their collapsed star exposes them and squeezes them together so tightly that, famously, a teaspoon of neutron star stuff would weigh as much as a battleship.

When neutron stars collide, smash-ups detected about once a day from Earth, the combined core of the stars collapse further, turning into a black hole.

Some of the detritus of these cosmic smash-up are elements more dense than iron, such as gold and the rare earth elements used in modern electronics. Gold rings riding on many folks’ fingers may have been born in just such a collision.

Sun Erupts Into Space. Photograph by NASA/Goddard Space Flight Center. A massive eruption of charged solar material lifts off the sun’s fiery surface in this NASA picture. Such “coronal mass ejections” trigger solar storms and northern lights when they are aimed at Earth.

Corona Crowns Solar Sphere. Photograph by Hinode/XRT. The sun’s corona, its superhot outer atmosphere, is revealed in this collage of images from the space agency. 

The sun’s surface measures about 9,940 degrees Fahrenheit (5,500 degrees Celsius), which is plenty hot. But the corona, stoked by the sun’s powerful magnetic field, is much hotter, its temperature measured in millions of degrees.

The collage shows “activity bands” in the corona, belts of more agitated activity in the sun’s upper atmosphere, which move up and down across our star as it undergoes its 11-year cycle of storm activity on the sun.

Jets Blast From Giant Star. Photograph by Andrew Cunningham, Lawrence Livermore National Laboratory: Richard I. Klein, University of California, Berkeley and Lawrence Livermore National Laboratory and Andrew T. Myers, University of California, Berkeley.  

A flame-like eruption flares away from an infant giant star, seen in this supercomputer simulation of stellar birth.

Such massive stars, perhaps 10 to 100 times heavier than the sun, pose a puzzle to astronomers—how do they form? The simulation helps explain how so much gas and dust might combine to create a giant star, with a great deal of accompanying fireworks.

By: news.nationalgeographic.com