Posted by on Aug 26, 2022 in Main |

The Milky Way in the glow of twilight

This month the nights become longer and we move towards unsettled weather. The autumn constellations are starting to show. Ursa Major, or the Plough, can be found low in the North. The ‘W’ of Cassiopeia is not far from the overhead point. Also on view this month we have, Aquarius the water carrier, Cetus the sea monster, Capricorns the sea goat, Pices the fishes, Piscis Austrinus the southern fish and Delphinus the Dolphin.

The summer triangle of Altair, Deneb and Vega remains high up. The southern sky is dominated by the Square of Pegasus. The bright star Capella in the constellation of Auriga the Charioteer is becoming more noticeable in the east. It will be overhead in winter evenings.

Although the four stars that form the Square of Pegasus are not the brightest, once found they will be easily recognised again. It is always an interesting project to count how many stars you can see within the square; you might be surprised by the result.

If you use the two right hand stars of the square and draw a line to the south you will reach a bright star very low in the sky. This star is Fomalhaut, in the constellation of Piscis Austrinus.

The Planets:-

JUPITER
The gas giant Jupiter is the ‘Star’ of the month. Closest to Earth on the 26th, when it is also at its brightest this year. At a radiant magnitude of –2.9, it lies in the constellation of Pisces and is visible all night long. Using binoculars or a low power telescope you can see its four largest moons, constantly changing position each night as they circle the mighty world.

SATURN
Located well to the right of Jupiter, Saturn lies in the constellation of Capricornus. It falls below the horizon around 3.30am. At magnitude +0.4, it is twenty times fainter than Jupiter.

NEPTUNE
Lurking between the Solar Systems two gas giants, Neptune is located in the constellation of Aquarius. Like Jupiter, the most distant planet is at its closest to Earth on 16th September, and is above the horizon all night long. But even at opposition, Neptune only reaches magnitude +7.8, so you well need binoculars or a low power telescope to see it.

URANUS
Found in the constellation of Aries. It rises above the horizon about 9pm. At magnitude +5.7 it is just visible to the naked eye, but I much better seen with optical aid. Have your binoculars or telescope ready on the evening of 14 of this month, when Uranus has a very rare occultation with the Moon.

MARS
Mars can be found in the constellation of Taurus. Starting the month below the Pleiades star cluster and above Aldebaran. If you have binoculars, try comparing the colour of the red planet and fainter red hue of Aldebaran. Mars rises around 10pm and shines at magnitude –0.3.

VENUS
Rising in the eastern twilight. The glorious morning star is shining at magnitude –3.9, and as the month progresses it sinks even lower into the glow of the dawn to totally disappear by the months end.

MERCURY
The innermost planet will be to close to the Sun for observation.

Special Events :-

3rd September – At 7.08pm the first quarter Moon will be close to the star Antares.

8th September – An almost full Moon lies to the lower left of the planet Saturn.

10th September – The Harvest full Moon.

11th September – The large Moon and Jupiter shine close together in the south east.

14th September – the almost half Moon between 10.27pm and 11.20pm moves in front of the planet Uranus. Such events are very rare, with the last occultation of Uranus visible from Yorkshire being back in 1953. But amazingly there are two Uranus occultation’s this year. The next being in December.

15th September – The almost half Moon lies below the Pleiades star cluster.

16th September – The almost half Moon is near the red planet Mars and the star Aldebaran.

20th September – After midnight in the early hours the crescent Moon will be close to the twin stars Castor and Pollux.

23rd September – At 2.04am nights become longer than days as the Sun moves south of the equator at the Autumn Eqninox

30th September – The crescent Moon is close to the star Antares.

The phases of the Moon for September are:-

First Quarter 3rd
Full Moon 10th
Last Quarter 17th
New Moon 25th