Conjunction of Jupiter & Saturn December 2020

Conjunction Background: Occasionally, two or more objects meet up with each other in our sky. Astronomers use the word conjunction to describe these meetings. The word conjunction comes from Latin, meaning to join together.
In astronomy, a conjunction occurs when two astronomical objects or spacecraft appear to be close to each other in the sky.
This means they have either the same right ascension or the same ecliptic longitude, usually as observed from Earth.
When two objects always appear close to the ecliptic—such as two planets, the Moon and a planet, or the Sun and a planet—this fact implies an apparent close approach between the objects as seen in the sky.
A related word, appulse, is the minimum apparent separation in the sky of two astronomical objects.
Conjunctions involve either two objects in the Solar System or one object in the Solar System and a more distant object, such as a star. A conjunction is an apparent phenomenon caused by the observer's perspective: the two objects involved are not actually close to one another in space.
Conjunctions between two bright objects close to the ecliptic, such as two bright planets, can be seen with the naked eye.
You can keep up to date with upcoming conjunctions by visiting 'Earthsky.org'

Description: The great Jupiter/Saturn conjunctions happen every 20 years. Each year, Saturn completes about 12 degrees of its orbit around the sun, whereas Jupiter completes about 30 degrees. Therefore, in one year, Jupiter closes the gap between itself and Saturn by about 18 degrees (30 – 12 = 18 degrees). In a period of 20 years, then, Jupiter gains 360 degrees on Saturn (18 x 20 = 360 degrees), therefore lapping the ringed planet once every 20 years.
On December 21st 2020,Jupiter and Saturn were at their closest separation in the sky since 1623, at just 0.1° apart

Conjunction of Jupiter & Saturn

Imaging Details

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