Jupiter and Saturn merged in the night sky Monday, and the Griffith Observatory livestreamed viewers as it happened.
Astronomers say that 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 this week they seemed closer together than since Galileo’s time in the 17th century. (Jupiter and Saturn were actually more than 450 million miles apart. Earth will be 550 million miles from Jupiter by now.
From our perspective, Jupiter and Saturn were only one-tenth of a degree apart, or about one-fifth the width of a full moon.
Monday was also the winter solstice in the Northern Hemisphere, the longest night of the year – and the summer solstice in the Southern Hemisphere.
It was the closest Jupiter-Saturn link since July 1623, when the two planets appeared slightly 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.
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.