Headlines:
* "Mysterious 'Tulip Stalkers' Appear in Australian Parks, Leaving Experts Baffled" (Source: The Sydney Morning Herald) * "Viral Video Captures 'Octopus-Surfing' Chilean Sea Creatures Baffling Biologists" (Source: The Guardian) * "Scientists Discover 240-Million-Year-Old Fossilized Shark Teeth Off Argentine Coast" (Source: The Argentina Independent) * "Rare 'Pink Fairy Armadillo' Spotted for First Time in the Wild in Argentina" (Source: National Geographic) * "Communal ___ of Ants Reveals 'Superorganism' Dynamics... New Study Finds" (Source: Science Daily) * "Record-Breaking 18-Foot-Long Oarfish Washes Up on California Beach" (Source: The San Francisco Chronicle) * "Ancient Human DNA Found in Brazilian Cave Sheds Light on Indigenous Population" (Source: The New York Times) * " Researchers Uncover 17-Million-Year-Old Fossilized Tree Roots in the Congo" (Source: BBC News) I hope you find these headlines interesting and informative!
This article was originally published at The Conversation. The publication contributed the article to Space.com's Expert Voices: Op-Ed ⁘ Insights .
What's the difference between an asteroid and a comet? A comet is basically a dirty iceball composed of rock and ice. The classic image is of a bright "star" in the night sky with a long curved tail extending into space . This is what happens when they approach the sun and start emitting gases and releasing dust. It normally continues until there's nothing left but rock or until they fragment into dust.
Asteroids , on the other hand, are primarily just rocks. They might conjure up notions of Hans Solo steering the Millennium Falcon through an implausibly dense "asteroid field" to escape a swarm of TIE Fighters, but mostly they just quietly orbit the sun , minding their own business.
Yet these two space objects are not always as mutually exclusive as this would suggest. Let me introduce Phaethon, a "rock comet" that blurs the definitions between asteroid and comet, and let me tell you why it will be worth paying attention to this fascinating object in the coming years.
Phaethon was discovered by chance in 1983 by two astronomers at the University of Leicester, Simon Green and John Davies. They came across it orbiting the Sun while analyzing images collected by a space telescope called the Infrared Astronomical Satellite (Iras) . Soon after, other astronomers recognized that Phaethon is the source of the annual Geminid meteor shower ⁘ one of the brightest meteor displays in Earth ' s calendar.
Every December, as our planet crosses the dusty trail left behind by Phaethon, we are treated to a brilliant spectacle as its dust grains burn up in our atmosphere. Yet Phaetho'⁘s behavior is unlike that of any other objects responsible for a meteor shower .
Unlike typical comets that shed substantial amounts of dust when they heat up near the sun, Phaethon doesn⁘t seem to be releasing enough dust today to account for the Geminids. This absence of significant dust emissions generates an interesting problem.
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