Conjunction of Jupiter, Saturn and Mercury January 2021

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: A conjunction is said to occur when two or more planets align in the night sky as seen from Earth.
It's all about line of sight, because Jupiter, Saturn, and Mercury each take a very different amount of time to orbit the sun.
Distant Saturn takes 29 years, Jupiter 12 years, and tiny Mercury just 88 days. A spectacular gathering of bright planets was the chief celestial attraction in the evening sky as Jupiter, Saturn and Mercury appear to crowd into tight quarters.
Low in the southwestern evening sky just 30 to 45 minutes after sundown, was what might be referred to as a celestial summit meeting, a triple conjunction, with the three planets fitting within a circle smaller than 5 degrees.
Brilliant Jupiter (magnitude –1.9), medium-bright Mercury (-0.9) and dimmer, yellow-white Saturn (+0.6) were contained within a 5-degree circle from Jan. 8 to Jan. 12, appearing closest together on Sunday evening (Jan. 10).

Conjunction of Jupiter- Saturn-Mercury

Imaging Details

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