Some celestial events happen often, like partial lunar or solar eclipses, Super Moons, or annual meteor showers.
But some celestial phenomena occur so rarely that you might only be able to catch them once or twice in your lifetime — if at all.
This month, Saturn’s and Jupiter’s orbits will align in a cosmic event that occurs about once every 20 years, but is rarely so close and visible to us at the same time.
The Great Conjunction on December 21 will be the closest conjunction since 1623, and the closest visible conjunction since the year 1226.
Halley’s comet returns to Earth’s neighborhood every 75 years — so depending on how old you are when you first see it, you might be able to see it twice.
Halley’s comet last approached Earth in 1986. Its next approach is scheduled for 2061.
If you missed watching Venus transit the Sun in 2012, unfortunately, you’ll never see it again. This celestial event only occurs every few hundred years.
The next time Earthlings will be able to witness a Venus transit will be Saturday, December 11, 2117.
Although Earthlings could witness 2-4 total solar eclipses each year, it’s rare for them to be visible from heavily populated areas, like 2017’s solar eclipse.
Edwin Remsberg/The Image Bank Unreleased/Getty Images
For any given spot on Earth, a total solar eclipse will be visible once every hundred years or so.
It takes Uranus, Neptune, and Pluto more than 100 years each to orbit the Sun. So at any given moment, these planets and dwarf planet will only be in that spot only once in your lifetime.
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