Look to northern sky for rare green comet
MIAMI - A rare green comet will zip by Earth for the first time in 50,000 years. It was last visible in the night sky during the Stone Age.
The cosmic visitor will swing by our planet at a distance of about 26.4 million miles.
Nicknamed "dirty snowballs" by astronomers, comets typically hail from the ring of icy material called the Oort cloud at our solar system's outer edge.
Comets are composed of a solid core of rock, ice and dust and are blanketed by a thin and gassy atmosphere of more ice and dust, called a coma. They melt as they approach the sun, releasing a stream of gas and dust blown from their surface by solar radiation and plasma and forming a cloudy and outward-facing tail.
Comets wander toward the inner solar system when various gravitational forces dislodge them from the Oort cloud, becoming more visible as they venture closer to the heat given off by the sun. Fewer than a dozen comets are discovered each year by observatories around the world.
The green comet, whose formal name is C/2022 E3 (ZTF), was discovered on March 2, 2022, by astronomers at Caltech's Palomar Observatory in San Diego. Its greenish, emerald hue reflects the comet's chemical composition - it is the result of a clash between sunlight and carbon-based molecules in the comet's coma.
Using binoculars during a clear night, the comet can be seen in the northern sky. As the comet nears Earth, observers will be able to spot it as a faint green smudge near the bright star Polaris, also called the North Star.
Early morning skies, once the moon has set after midnight for those in the Northern Hemisphere, are optimal for viewing the comet.
Finding a remote location to avoid light pollution in populated areas is key to catching a nice view of the comet as it journeys past our planet heading away from the sun and back toward the solar system's outer reaches