Welcome to this month’s update to find out what’s in the night sky for September.
In the Elan Valley International Dark Sky Park, astronomical darkness lasts for six hours from 10.10pm and increases as the month progresses, providing more time to view the Milky Way and other astronomical treasures.
The New Moon falls on 11th September and the Full Moon on 26th September.
This month we say goodbye to Summer and greet Autumn, commencing on September 23rd, which is otherwise known as the Autumn equinox.
An all-sky view of the constellations from 10pm on 1st September from in-the-sky.org – this is a printable map – click tap the image to download the pdf
To learn about the constellations, you can tap the image above which will download as a printable PDF.
Planetary Conjunctions During September
The Moon sweeps past a few planets this month, providing an opportunity to find them easily.
Moon and Mars Conjunction
7th September at 1.30am: The 20% Moon passes on the left-hand side of Mars.
Moon and Jupiter Conjunction
9th September at 4.30am: The 4% illuminated Moon rises with Jupiter above.
Moon and Saturn Conjunction
26th September at 8.30pm:
The Full Moon and Saturn at the eight o’clock position travels through the night sky in close proximity.
Lunar Occultation of Venus
14th September from 11.33am
We won’t see the beginning of this daytime transit as the Moon will be below the horizon. Look to the southeastern horizon at around 11.15am and you will see the Moon rising. At 11.33am, Venus will emerge from the moon at 11.33am, at the 1 o’clock position. Telescopes may reveal Venus’ crescent phase. Do not point the telescope at the Sun, as it is very dangerous.
Constellation of the Month: Andromeda
This month, the constellation of Andromeda is well-placed in the east as darkness falls. It is easily found by looking for the neighbouring constellation of Pegasus, which comprises a giant square as larger as on outstretched hand, held out at arm’s length (20 degrees). At the top left corner of the square is a line of stars, which is the constellation of Andromeda. Pegasus and Andromeda are linked together.
This constellation harks back to ancient Greece, where Andromeda’s mother, Queen Cassiopeia, angered the gods by boasting of her beauty. Poseidon sent Cetus, the sea monster to ravage the kingdom. As a token of appeasement, Cassiopeia offered her daughter as a sacrifice by tying her to a rock by the sea as an offering to Cetus. She was saved at the last moment by the hero Perseus, who flew down on Pegasus, the winged horse, to whisk Andromeda away to safety. They fell in love and got married, living happily ever after.
A Gigantic Nebula
The North American Nebula – NGC7000
Coordinates: RA 20h 59m 17s | Dec +44° 31′ 44″
This nebula can be seen in a dark, night sky with fully, dark-adapted eyes. It can also be seen with small 8 x 42 binoculars, looking like a faint, large, foggy patch of greyish light against the dense star fields of the Milky Way. It resembles the shape of the North American Content.
How to find it
All you have to do is look for the Summer Triangle which comprises the three bright stars: Deneb in the constellation of Cygnus, Altair in the constellation of Aquila and Vega in the constellation of Lyra. Find the star Deneb, raise the binoculars to your eyes and scan slowly left until the nebula pops into view. Situated 2590 light years from Earth, it would take 69.5 million years to get there in the most modern space module that can carry humans.
A Veil of Gossamer
The Veil Nebula – NGC 6960
This is another wonderful object that is well worth searching for if you have access to dark, rural skies. There’s many names for this celestial treasure: Witches Broom Nebula, The Filamentary Nebula, The Finger of God and the Lacework Nebula.
How to find it
Coordinates: RA 20h 45m 38.0 | Dec +30° 42′ 30″
Look for Deneb, then jump to the star in the centre of the constellation called Sadr. Then hop over to Aljanah, on the left hand ‘wing’ of Cygnus, then look for a small star below called 52 Cyg. With an OIII filter on your widefield eyepiece, sight 52 Cyg and you will see stunning, gossamer-like filaments running either side of the star.
This is just one part of a huge complex called the Cygnus Loop, containing filamentary nebula, the remnants of a massive star which blew apart several thousand years ago. Spanning 110 light years, it is as large as six full moons from our perspective. This supernova remnant is a cloud of ionised gas and dust. It is a challenge to search for but worth the effort!
Image credit: X-ray: NASA/SAO/CXC; Optical: John Stone (Astrobin); Image Processing: NASA/SAO/CXC/L. Frattre, N. Wolk
