CAPE CANAVERAL, Fla. (AP) – Jupiter and Saturn will merge in the night sky Monday, appearing closer together than they have been since Galileo’s time in the 17th century.
Astronomers say so-called conjunctions between the two largest planets in our solar system are not particularly rare. Jupiter passes its neighbor Saturn every 20 years in their respective orbits around the sun.
But the one coming is very close: Jupiter and Saturn will be only one-tenth of a degree from our perspective, or about one-fifth the width of a full moon. They should be clearly visible around the world a little after sunset, weather permitting.
Cast the winter solstice in the Northern Hemisphere, the longest night of the year – and the summer solstice in the Southern Hemisphere – and this just-in-time-for-Christmas spectacle promises to be one of the greatest Great Conjunctions.
“What is most rare is a close conjunction that occurs in our night sky,” said David Weintraub, an astronomy professor at Vanderbilt University. “I think it is fair to say that such an event usually only happens once in a person’s life, and I think once in my lifetime is a pretty good test of whether something deserves to be considered rare or special stamped. ”
It will be the closest Jupiter-Saturn pairing since July 1623, when the two planets appeared a little closer. However, this conjunction was almost invisible due to the proximity of the sun.
Significantly closer and clearly visible was the March 1226 conjunction of the two planets – when Genghis Khan conquered Asia. Monday’s conjunction will be the closest link visible in a long time.
Saturn and Jupiter have been getting closer to the southwestern sky for weeks. Jupiter – bigger and closer to Earth – is much brighter.
“I love to see them getting closer and closer together and the fact that I can see it with my naked eyes from my back porch!” Virginia Tech astronomer Nahum Arav said in an email.
To see it, you need to be ready shortly after sunset on Monday, looking southwest, quite low on the horizon. Saturn becomes the smaller, fainter blob at the top right of Jupiter. Binoculars are needed to separate the two planets.
Despite appearances, Jupiter and Saturn will, in fact, be more than 450 million miles (730 million kilometers) apart. Earth, meanwhile, will be 550 million miles (890 million kilometers) from Jupiter.
A telescope will capture not only Jupiter and Saturn in the same field of view, but even some of their brightest moons.
Their next super-close pairing: March 15, 2080.
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