Tomorrow, watch out for the rare ‘Christmas Star’
On Monday, December 21 just after sunset, there will be a Christmas conjunction of Jupiter and Saturn, like the Star of Bethlehem, that was speculated to be the conjunction of Jupiter and Venus in 3 BCE.
Although conjunctions of Jupiter and Saturn happens about every 20 years, this is the closest visible conjunction for almost 800 years, which makes it special.
The closest separation between Jupiter and Saturn will be just 6.1 arc minutes (an arc minute is equal to one sixtieth of a degree), about 5 hours after we are able to see the pair at around 6.45 p.m. on Monday, December 21 just after sunset. For angular reference, the Full Moon is about 30 arc mins or half a degree in diameter.
Courtesy https://astronomy.com/news/2020/12/jupiter-and-saturn-will-form-rare-christmas-star-on-winter-solstice
You need to go to a place where you have a clear view of the southwestern sky about 25 degrees above the horizon. With the naked eye, they will look like a single bright star. With a good pair of binoculars, they will be resolved and with a telescope, you may see Saturn with its Rings and Jupiter with its Moons in the same narrow field of view. The four brighter Moons of Jupiter are seen in orbit 2 to 10 arc mins from Jupiter, and Saturn will also be in that range on the 21st with a separation of about 6.5 arc mins.
Watching the pair in about the same direction after sunset a few days before and after, you will see the two planets move closer and apart. The next closer conjunction is in 2080 when they are 6.0 arc mins apart.
There was closer conjunction of 5.2 arc mins in 1623, but that was too close to the direction of the Sun to be visible. The last visible closer conjunction was in 2.1 arc mins in 1226 after VijayaBahu III, had repelled the invasion of Kalinga Megha.