On the morning of March 31, 2020, these three worlds will be at their mutual closest in 20 years.
For the past few weeks, Mars, Saturn, and Jupiter have all shone prominently in the pre-sunrise skies.
As the only naked-eye planets orbiting exterior to Earth, they’ve all lined up numerous times this month.
On March 4, 2020, they were equally spaced, with 8° separating each of these three outer planets.
On March 26, 2020, just three weeks later, they were equally spaced more tightly, with just 3.5° of mutual separation.
The fact that planets are located at different distances from the Sun ensures that they move at different speeds.
This is why the separation and even the order of these worlds changes, from our perspective, over time.
In the pre-dawn skies of March 31, 2020, skywatchers globally will be treated to a spectacular alignment.
First off, Mars and Saturn will experience a conjunction, separated by just 0.9°.
Jupiter remains close by, located approximately 6° away from the close pair, making them easier to spot.
Through a telescope, all three of these worlds will appear in their nearly-full phase, as demanded of outer planets.
It’s a prelude to December 21, 2020’s Great Conjuction, where Saturn and Jupiter meet in the post-sunset skies, just 0.06° apart.
Mostly Mute Monday tells an astronomical story in images, visuals, and no more than 200 words. Talk less; smile more.
Ethan Siegel is the author of Beyond the Galaxy and Treknology. You can pre-order his third book, currently in development: the Encyclopaedia Cosmologica.