Word: purcelle
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Astrophysicist William Purcell knew that if he looked at the center of the Milky Way, he would see what is known as antimatter: bizarre subatomic particles that resemble ordinary protons and electrons but carry an opposite charge. But when NASA controllers trained the orbiting Compton Gamma Ray Observatory on this...
When massive stars explode as supernovas, for example, they create a periodic table's worth of radioactive elements, some of which decay into antielectrons, known as positrons. A black hole, scientists believe, can also produce electron-positron pairs by superheating the material that spirals into its gravitational sinkhole. It was...
A competing theory, which Purcell favors, suggests that exploding supernovas may be the force that creates the positrons and catapults them to such great heights. There are certainly plenty of massive stars close to the Milky Way's core that are capable of generating explosions with sufficient force. The rate...
It's a puzzle, in other words, that could take years to solve. And that's what Purcell and others find most exciting. The Milky Way--so familiar and in many ways so humdrum--still hasn't lost its ability to surprise.
John and Susan Purcell toured Yellowstone this winter the new, noisy way--by snowmobile. And like thousands of visitors who clamber onto winter scooters every week to explore America's oldest national park, they can't get over those close encounters with wild elk, moose, trumpeter swans, coyotes and, closest...