Venturing into the cosmic nursery, Rob Nolan captures the Orion Nebula’s Trapezium, showcasing the beauty of stellar birth
Well, the start to 2024 has certainly been anything but mundane! The weather’s been extremely changeable, from warm to cold and back again! Thankfully, a few clear nights have been enjoyed by those of us willing to brave the frost, and that’s allowed me a bit of time to have another go at one of the UK’s favourite and arguably most recognisable winter nebulas.
Orion the Hunter is one of the most noticeable constellations in our night sky. Once you locate it (usually via the three bright stars that make up Orion’s belt), the two brightest stars in the constellation are Betelgeuse and Rigel. About where Orion’s ‘knees’ would be is the Orion Nebula (also known as Messier 42). When we’re looking into the core of the Orion Nebula, we’re gazing into our nearest stellar nursery, where new stars are born.
The Orion Nebula is what’s known as a diffuse nebula, meaning its visible to the naked eye and doesn’t require photographing using special narrowband filters. It’s also reasonably close – in cosmic terms – at 1,344 light years from Earth. Estimated to be 24 light years across and with a total mass about 2,000 times that of our Sun, it remains one of the most intensely studied celestial features in our night skies.
The core of the nebula is what’s known as the Trapezium, and this is where the stellar nursery is situated. Astrophotographers frequently become frustrated photographing this target, due how bright the core actually is compared with the surrounding Nebula. This leads to frequently ‘blown out’ images as we try to obtain a good image of the rest of the Nebula and surrounding gases. To try to combat this, we use a technique similar to that of ‘bracketing’ in terrestrial photography, where photos are taken at different exposure lengths and then blended into a single image to create a more even light across the image.
For the image opposite, I shot a bunch of 10-second subs (exposures) for around half an hour, and also around six hours’ worth of 180-second subs. I then merged the core of the Nebula from my shorter subs into my overall image, allowing me to present a highly detailed image of the entire Nebula.
I won’t lie, I’m pretty happy with this image, as it’s the culmination of three years of painstaking practice on this target – with the help of some new equipment of course!
The night sky, February 2024 – Rob’s guide for your stargazing this month:
February this year is a relatively quiet one for celestial events, but it is a Leap Year, so we do get an extra night in the diary to explore the skies!
As the image of the month suggests, it’s a great time of year to explore the Orion Constellation and the Orion Nebula. You can photograph this yourself with just a decent camera, long focal length lens and a tripod. Just take short 10 to 20-second exposures and you should be able to make out the purplish colour of the Nebula.
Other winter constellations to explore are Taurus and Gemini as they continue to drift westward in our sky, due to our changing perspective looking outward to the universe as we orbit the Sun. Looking east, new constellations begin to move into view, including Leo and Boötes.
It’s also a great time to grab those binoculars and explore the M35 star cluster, located in the constellation of Gemini. This particular swarm of more than 2,000 stars is located 2,800 light years away, towards the outer edge of our own Milky Way galaxy. Star clusters are amazing to observe, and I plan to image more of them this year!
Closer to home, we have a few events this month to look out for around the Moon:
On the 7th, before dawn, Venus will appear to the left of a narrow crescent Moon, illuminated in the twilight. Grab your binoculars to get a good view!
On the 14 and 15th, Jupiter will be seen as a bright object close to the Moon.
On the 16th, between 7pm and 10pm, the Moon will pass in front of the Pleiades cluster.
Next month we can look forward to the Spring Equinox – and a passing comet!
Until next time, clear skies.