EYES ON THE NIGHT SKY - AUGUST 2021
Welcome to the August edition of Eyes on the Night Sky. True darkness returns this month for those who love to seek out more distant deep sky objects or marvel at the structure of the Milky Way, which emerges in the southern sky as darkness falls. For many amateur astronomers, it is a great start to the stargazing season, with a spectacular meteor shower, stunning nebulae and star clusters to discover.
Perseid meteor shower
The Perseid meteor shower is expected to be a great one this year, peaking on the late night of 12th August into the early morning. The Moon will set at around 10pm, which will provide the perfect dark skies to watch the most spectacular meteor shower of the year.
Radiating from the constellation of Perseus, you don’t have to look in that direction as the ‘shooting stars’ appear anywhere in the sky. As these dust particles, thought to be the debris of Comet Swift/Tuttle hit our atmosphere, the speed of the object plus the friction with our atmosphere causes the meteoroid to heat up and catch fire, leaving persistent trains and even a smoky tail. It is so easy to watch this – just wrap up warm with a drink, lie on a blanket, look up and enjoy! It is believed 150 meteors may be seen in the early hours on 13th August.
The New Moon falls on 8th August and the Full Moon on 22nd August. The full Moon rises at around 9pm in the south east, following Jupiter and Saturn.
A Binocular Feast
This is a great time of year to study the nebula and star-rich area of the constellation of Sagittarius.
Using your binoculars, try and find Messier 25, an open star cluster which will resolve as an oblong shape. You can actually see it with the unaided eye but it looks better through binoculars.
Whilst in the area, pan your binoculars directly westwards and you will come across Messier 24, or the Small Sagittarius Star Cloud, which the binoculars will resolve up to 1000 stars in its field of view! Finally, scan westwards again to find open cluster Messier 23.
Finally, Messier 8, which is an emission nebula and I around 5000 light years away. Comprising energised hydrogen from radiation emitting from Herschel 36, it also is a stellar nursery. Better known as the Lagoon Nebula because of the dark lane that runs through its centre; similar to a shallow body of water with a sandbar running through it. It can be spotted with the unaided eye in dark skies but through binoculars, you can make out around six stars with some nebulosity. If you are able to spot another faint hint of nebulosity, that is the nearby Messier 20 (Trifid Nebula).
Messier 8 (Lagoon Nebula)
Coordinates: RA 20h 45m 38s | Dec +30° 42′ 30
The Veil Nebula (Western Veil nebula) is a challenge for those with telescopes of six inches aperture and larger, but the detail in this amazing nebula starts to be seen in telescopes of eight inches and above.
Look for the cross shape which forms part of the constellation of Cygnus and look for the star Deneb, which forms part of the Summer Triangle.
Look for the next star Sadr, which is in the centre of the cross asterism and hop to the left hand star Aljanah. This is where it gets tricky, as the star where the Veil nebula is situated, 52 Cyg, is tricky to see with the unaided eye unless you are in dark skies. You might want to star hop using your finder scope; 52 Cyg can be found with the increased magnification the finder scope offers. Once you have sighted 52 Cyg, Look through the eyepiece of your telescope and see if you can discern a faint, grey filament.
It is well worth purchasing a visual filter to screw onto the end of your eyepiece; an O-III narrow band-pass filter is ideal for this as it narrows the type of wavelengths along the visual spectrum and enhances the area of wavelength to make the nebula ‘pop’ with detail. Once seen with the O-III filter, it will be never forgotten, as the nebula appears like a discarded, shimmering veil of gossamer and is a sight to behold. This object forms part of the Cygnus Loop and you may want to use a low magnification eyepiece to take in this nebula complex, which is a huge remnant of an exploded dying star encompassing an area the size of three full moons, situated about 2600 light years away. The star itself was thought to be 20 times larger than our Sun.