Monthly Sky Guide

December's Guide To The Sky.

Mercury pops up briefly with Venus looking bright above it in the afternoon sky, Jupiter and Saturn are still up until around 10:00pm - 11:00pm, Uranus and Neptune are both up most of the night but placed between constellations so might be hard to find and Mars is close to the Sun in the morning sky, so may be a challenge to spot this month.

December 2021

A lovely morning thin crescent moon rises around 5:00am with Mars rising to its bottom left an hour or so after - allowing you to see them both just before sunrise. The blue star Spica in Virgo with be higher to their right.

December 2021

This morning you can see the same cool sights as yesterday, but with the Moon having moved past Mars and at a really thin about 1% lit, rising around 7:00am. You’ll have to get out quick and spot it before the Sun rises. See if you can also see the big bright burning star, Arcturus, high above them - creating a cool morning welcome to the day.

December 2021

From around 4.30pm this evening watch and see if you can spot the brightening Venus as the sky darkens with the setting Sun. You should easily see the gas giant Jupiter up to its left with the ringed planet Saturn slightly fainter in between. Grab a pair of binoculars or a scope and pop it onto Venus and you will see that it is around 25% lit. It will look like a thin crescent moon. You shouldn’t need a moon filter to dim it down in order to see it.

December 2021

Go back to Venus this evening and you will see that the Moon has popped up just to its right. It will again be a very thin crescent. Maybe with a pair of binoculars you may get both in view at the same time. The Moon will be moving past all these planets as the month goes on, so you can follow its journey across the sky.

December 2021

Another awesome view this evening as the Sun sets around 5:00pm. Venus, at 16% lit, Saturn and Jupiter will again appear in the sky with the Moon more easily visible between Venus and Saturn. You may also spot a bright blue star higher up from the triage of planets. It’s the star Altair which is the tail of the Eagle Aquila.

December 2021

The Moon is now 22% lit, so is waxing and getting fuller each night as it moves left across the sky in its orbit around Earth. It now sits between Saturn and Jupiter - slightly lower than the planets themselves.

December 2021

This evening the Moon has now shifted past Jupiter sitting to its left. You can now see how much and how quickly the Moon moves through our skies. It has waxed to 35% now so will start looking much brighter over the next few days.

December 2021

Time to spot some cool objects on the Moon seeing as we have been watching it for the last week or so. Using a moderate sized telescope, see if you can spot the crater Albategnius around the mid point of the Moon. You will see that that the shadows that are cast in the crater create what looks like a smiling face looking back at you from the Moon. To help you easily find it, you can use a moon map or app called, moonglobeHD. And of course, we will have pics for you in our facebook group and website.

December 2021

Fancy another face on the Moon? Then have a peek at the crater, Clavius, around 10:00pm. Two higher regions within the craters shadow just get a glint of Sunlight on them to make it seen as if eyes are peeking out from the darkness. It's towards the bottom of the Moon.

December 2021

The Geminid meteor shower peaks over the night into the morning, but it is prob best viewed after midnight, they say that tonight and tomorrow night are good times to spot them.

As the meteors radiate from the constellations twin’s heads, Castor and Pollux, the constellation Gemini is higher up later in the night giving you the best chance of seeing more.

They say that they peak at an average of around 60 - 70 an hour, but this all depends on how dense the dust cloud we are passing through is and the light pollution in your area. Some say it can peak at 120. Gemini is low to the East as the Sun sets, but will climb higher as the night goes on.

The debris we see burning up as shooting stars are from an asteroid not a comet. Like most others, it takes only 1.4 years to orbit the Sun - leaving behind a dust lane that creates this annual meteor shower.

The Moon is in the way a bit but sets around 3:00am, so hard-core astronomers have a few hours after to spot some Christmas shooting stars.

December 2021

Today is the start of the winter solstice where the Earth's poles are at their maximum tilt away from the Sun. So we have the longest night tonight, where the Sun's central disc reaches its lowest point in the sky relative to the stars and the nights start getting shorter.

December 2021

The peak of the Ursid meteor shower happens in the early morning. If you look toward Ursa Minor, Polaris the North star is at one end while the radiant for these meteors are towards the other. The Ursid meteor shower only really generates a handful of shooting stars from a stream of debris left behind by comet 8P / Tuttle. A bright Moon that’s up all night may wash out all but the brightest.

December 2021

The 76% lit Moon occults a star around 4.16am - a minor star in Leo will slip behind it, disappearing until 5.09am, when it will appear from the other side of the Moon. You can actively watch the Moon as it drifts through our skies.

December 2021

See six planets in one night as the Sun sets. Around 4:00pm onwards you may be able to see (with a low horizon) just below the planet Venus, Mercury has popped up. Spot these two and you’re on your way.

As we know, Jupiter and Saturn are also up just to the left of Venus, so that makes four planets spotted. Now you’ll have to wait a little later until its darker to try and spot the next two - a telescope will be needed.

Uranus reached opposition in November, so should still be brighter to see - although its location is a bit tough. It will be sat in the middle of nowhere between Cetus’ head and Aries. You will need to star hop to get a glimpse of it.

The same it seems with Neptune. Tt is sat in between one of Pisces fishes heads and Aquarius just above left of Jupiter. So an app is probably a must to find these two dimmer planets. You have most of the night to spot them.

Objects of the month

Naked Eye Object

Geminid meteor shower we spoke about, as they are a great one to see and as good if not better than the more famous Perseids. Being darker and colder than in August, there’s more time and less light pollution to see them.

Binocular Object

Comet 2021 A1 Leonard, I know we spoke about this comet last month, but it does seem to be getting brighter so even easier to see with binoculars this month. Passing just under Venus over the month, you will need a low clear horizon. But some are suggesting it my become a naked eye comet.

It seems it will be best between 1st - 13th December, where it is to the right and below Venus - moving under and past it on 17th - 18th. Now, it may be a bit tough as the Sun hasn’t really set, but I think its well worth a peek if you can get up high and get a low horizon. Just be careful with the setting Sun.

Telescope Object

Now it wouldn’t be December without this object being mentioned. So if you have a telescope why not see if you can find the Christmas tree cluster. In Gemini, start at the twin pollox’s head, move down to his left leg to the star Alzirr. Not far from there you can find the Christmas tree cluster.

An awesome little cluster that’s formed by a group of very young stars that actually look like a Christmas tree with a bright star at its top, just like your tree at home.

There is also the cone nebula here, but it’s very hard to see. Those with a camera may pick it up if you fancy some astrophotography. It can be found by the designation NGC2264 on apps.

Clear skies guys, and remember... there’s a billion worlds in your back garden!


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