Don't Miss This Planetary Treat!

Dec 20, 2020 By Jocelyn L.
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Have you ever imagined looking up at the night sky and seeing not one, but two planets in our solar system right next to each other?

For the first time in 400 years, on December 21, Jupiter and Saturn, two of the biggest planets in our solar system, will appear very close in the night sky.

Let’s take a closer look at this phenomenon and how to view it.

What are Planetary Conjunctions?

Planetary conjunctions occur when two planets line up roughly with Earth in their orbits around the Sun. This allows these two planets to appear extremely close to each other when viewed from Earth. However, in reality, these planets are separated by the great distance between their orbits.  

Planetary conjunctions occur because each planet orbits around the Sun in different time periods, eventually allowing them to line up with Earth’s orbit when one is passing the other in its orbit.

The time it takes for this to occur differs based on each planet’s orbit. For example, Saturn and Jupiter are in planetary conjunction every 20 years, whereas Uranus and Neptune are in planetary conjunction every 171 years. The most common conjunctions are between Earth’s moon and another planet. These conjunctions typically occur once every month.

This year’s planetary conjunction between Jupiter and Saturn is extremely special because of how close they will appear in Earth’s night sky. They will appear to be touching each other, a view that will not occur in another 800 years. Also, because Jupiter and Saturn are the two biggest planets in our solar system, this conjunction between them is often referred to as the Great Conjunction.

How To View The Great Conjunction?

To view this planetary conjunction, look southwest in the night sky on December 21, ensuring that no objects are blocking your view of the sky.

Jupiter will look like a bright star, whereas Saturn will appear dimmer and emit a yellow tone. These two planets will look like they are touching each other in the sky. Prior to and following December 21, Jupiter and Saturn will still be visible, though they will not appear as close to each other in the sky.

Planetary conjunctions are rare, and this one is even more special because Jupiter and Saturn are two of the biggest planets in our solar system. Don’t miss out on this opportunity to view these two giants right next to each other in the night sky!

Sources: NASA, Washington Post, Planetary.org