December 21 Great Conjunction Christmas Star and Winter Solstice Sun

December 21 2020

Today marks to very special celestial events. It is the The Great Conjunction, also known online as the Christmas Star, and The Winter Solstice.

I wanted to address both again for quick reference and perhaps ease any disappointment if the weather does not cooperate.

 

The Great Conjunction of Jupiter and Saturn

This has been called the Christmas Star because in the sky, both Jupiter and Saturn may appear close enough to look like a single bright start.

They will be separated by less than 1º, which will be easy to see with the naked it. However, with a telescope both in view will be better than Galileo has with his first telescope in 1623. That was the last timer they were this close.

 

NASA: Planetary Alignment

We are seeing Jupiter and Saturn right next to each other only because of this position on all orbits.  Saturn is ‘behind’ Jupiter, but they are not close.

 

 

NASA: Where To Look (if the sky if clear)

Where: Look just to the left and up from where sunset occurs.

When: Best about 20 to 30 minutes AFTER sunset.  It’s early today at 4:43 PM.  So you should see it by 5:15 PM, if the sky is clear.

How Long: You have about 1 hour until the planets set.

 

How Close Will The Planets Be?

Dr. James O’Donogue made this visualization. The planets will NOT be in front of the moon. They will not be near it!  However, if they were by a full moon, this is how close they would appear to scale.

 

 

What We Saw Yesterday 

This was my view on Sunday, just one day prior to the closest pass.  With my iPhone it only looks like a bright dot… but wait!

 

Telescope View

Local astronomy photographer James Willinghan captured this amazing view on Sunday, also one day prior to the closest approach.  He labeled both planets and their moons.

 

 

What if you miss it?

If the clouds are in your way, yes you will miss the positions. But they will remain pretty close in view for the next week or two as they slowly move apart. If you missed the last week, you can still find a clear evening to capture this.

 

 

Winter Solstice

Today was also the lowest angle of the sun all year! Here is a breakdown from the Baltimore perspective.

 

Winter Solstice Sun In Baltimore

 

 

Today December 21 is the shortest day of the year. It is the lowest sun angle for us in the sky. But this is NOT the latest sunrise and earliest sunset, nor the farthest from the sun.

 

 

It is a strange result of the tilt of our earth, while the sun is rounding the corner on the elliptical orbit. In fact, Earth reaches the closest point to the sun on January 2 (2021). This is called perihelion and we are about 3 million miles closer to the sun than in July. But it doesn’t influence our temperatures.

Latest Sunrise: 7:25 AM on December 27

Earliest Sunset: 4:43 PM on December 1 -14 (about the same for 2 weeks).

 

Comparing Sun Angle

At Noon on The Winter Solstice, the highest sun angle of the say will be 27.3º above the horizon.  This is the same height above the horizon in Baltimore as only 8:15 AM on the Summer Solstice.

 

 

Gaining Daylight

We begin to add 2 more seconds of sunlight tomorrow. It may not be noticeable, but it increase each day will grow, and be a full minute longer by December 27.  Fast forward to January 7 and we begin to gain an additional 1 minute or more each day.

 

These two charts show the sun times and change of daylight length each day from today through January 11.

 

 

Christmas Arctic Front

This is all about the timing to determine how much snow can fall and when we get into the deep freeze. We still see roughly a 12 hour difference between the two main models.

Click here to see my report on this

 

FITF Shop Open

My ‘bonus’ daughter Jaiden and wife showing off our popular Maryland Hoodies. Unisex and women’s items all produced in Maryland.

Click here to see this and many other new items.