Monthly Sky Guide

September's Guide To The Sky.



1st
September 2021

If you missed last months Jupiter moon transits don’t worry to start the month off there is another early this morning. Callisto Jupiter’s dead moon and one of the most heavily cratered objects in our solar system transits the planet around 2.33am setting before the transit ends.



2nd
September 2021

A star disappears behind a 24% lit moon this morning around 1:12am reappearing around 2:04am depending on location, so you can watch the moon pass in front of a star.



3rd
September 2021

If you missed yesterday’s occult there is another this morning around 3:41am reappearing at 4:38. So, a second chance to see this cool phenomenon.



4th
September 2021

This morning’s thin crescent moon is not far from the great binocular object the beehive cluster or Presepe in cancer the crab. It is full of all different coloured and aged stars.



5th
September 2021

Morning IO will be seen transiting Jupiter followed by its shadow just after 1am.

As Jupiter is only just passed its opposition last month we are still getting some good views and transits. Like tonight’s of Europa the frozen moon full of ridges and cracks in its ice will transit the planet around 11:12pm followed by its shadow just after midnight.

Stay up a bit later and you’ll see Ganymede the largest moon in our solar system start its journey across the planet at 2:03am with its shadow following at 3:47am. Its also the only moon with its own magnetic field that can cause aurora like ours on earth.



6th
September 2021

Great chance to spot a very thin 1% crescent moon about an hour before sunrise, be careful when looking near the Sun. It will be to the left of the bright blue star Regulus in the constellation LEO also known as the harbinger of Spring, or the kings star.



7th
September 2021

There’s also another opportunity to spot the thin crescent but this time in the more friendly hours of the afternoon rather than yesterday’s early morning, as it has now passed to the other side of our Sun setting about half an hour after it.



9th
September 2021

This evening the moon will not be far from the planet Venus, the goddess of beauty did you know she spins the opposite way to all the other planets and a day there is longer than a year. Have a think about that as you look up at this awesome planet this evening.

You may spot a bright star called Spica just below left of the moon creating a triangle between them and Venus.



11th
September 2021

Fancy an asteroid hunt 2 Pallas reaches opposition today in the constellation Pisces, the fishes. It is said to be able to spot even with just binoculars but you will need an app to star hop to find which white dot is the asteroid, It is one of the largest around the same size as the UK.



13th
September 2021

Pop your scopes on the moon and see if you can spot the lunar X and V across its terminator, that’s the shadow part where the sun glints off the top of mountains and craters creating illusions like the X and V.



14th
September 2021

Mercury reaches its greatest eastern elongation meaning this evening is a great time to go out and try to spot it but it will be setting 20 mins after the Sun so you’ll have to be quick and have a low horizon. Mercury is quite a small planet in fact it only just bigger than our own moon.

Neptune the god of the sea also reaches opposition tonight best after 9pm the later the darker the skies will be and the easier to find it. Neptune is positioned in between Aquarius and Pisces so a bit of star hopping will be needed to find it. 2 Pallas is above right of it if you fancied looking.



15th
September 2021

The Moon, Saturn and Jupiter will make a nice curved line in the evening sky.



17th
September 2021

The moon will be sat in between the planets Jupiter and Saturn this evening, Saturn being to its right and Jupiter to its left, there will also be another transit but this time of Callisto’s shadow starting at 11:43pm and crossing the planet.



20th
September 2021

Tonight’s Full Moon is known as the harvest moon as it is the closest one to our autumn equinox, it gave farmers the que to start harvesting their crops.



22nd
September 2021

Today starts the season of Autumn, as the Sun crosses the celestial equator good news for us astronomers as the dark skies are coming.



27th
September 2021

Something for the keen eyed astronomer, if you can find Jupiter in the daylight around 3:49pm, although it doesn’t rise in UK till around 5:30pm you may see a shadow transit of the moon Ganymede, a go-to scope will probably help a lot here finding the planet but it is possible to see it during the day,




Objects of the month



Naked Eye Object

Cygnus - A swan flying through a Milky Way


Pop out after it gets dark and look straight up, if clear enough you may make out a slight milky band, our galaxy, well one of its arms. You will probably notice a big bright blue star, that’s Vega.

To its left is the star Deneb the tail of the swan, move right and you should spot a yellower star called Sadr this is the body of Cygnus above and below are 6 stars each 3 representing its spread wings across the night sky.

Two more stars to the right and you have gone down the swan’s neck sitting at Albireo its head, This is a famous double star that looks awesome through a telescope.

So go out look up and imagine a great swan gliding through the Milky Way.


Binocular Object

Kembles Cascade


The constellation Camelopardalis the giraffe is a more modern one and not a really well know constellation but there are a couple of cool objects for you to spot with your binoculars.

The constellation is pretty much three stars in a triangle, an extra one on the bottom line and a lone star added to represent the giraffes long neck.

It can be found to the left of Perseus, below left of Cassiopeia the sideways W, have a peek around the bottom line of the constellation where the middle star lies or look on you app for NGC 1502 this is Kembles Cascade a cascade of stars which looks great in wider field of views flowing down from the constellation.

While here look around see if you can spot a kite shape of stars, Kembles kite


Telescope Object

Triangulum Galaxy


Now almost all of us have heard of the Andromeda galaxy but just below this is the Triangulum constellation, yeah you guessed it 3 stars representing a triangle.

But in between it and Andromedas star, Mirach, is a great little galaxy to spot, the Triangulum galaxy (M33).

It is a spiral galaxy 2.73 million light-years from Earth and the third largest member of the local group of galaxies inc Andromeda, so pop out and see one of our neighbours.



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

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