Rho Ophiuchi Cloud Complex

This is perhaps one of my favourite deep-sky objects for its breathtaking structure. It shows up in many of my Milky Way photos and it’s hard to find a more colourful region in the entire night sky.

At first glance, the most striking feature is the sheer amount of colour. Why is it so colourful?

Well, the pinkish-red regions got their colour from a process called ionisation. Have you ever seen neon light that glows pinkish red? Neon lights glow pinkish-red because there is hydrogen in them; the pinkish-red nebulas in the image are made up of hydrogen too. They are gigantic neon lights hundreds of light-years across, made of hydrogen gas, powered by extremely powerful stars!

The yellow and blue parts have their colours for different reasons. The blue regions are reflected light whereas the yellowish part is light going through the clouds. They have different colours because blue light tends to bounce off small particles whereas red-orange-yellow light just goes through(Rayleigh scattering). This might sound like physics from an alien world, but we actually see this phenomenon every day. That’s why we have blue skies and yellowish sunsets!

Another striking feature is the dark nebulas; those are thick-dense interstellar dust no visible light can penetrate through. The long streak of thick clouds actually makes a dust lane that connects to the milky way.

This region is sometimes called the ‘Antares Nebula Complex’ because it hosts the brightest star in the constellation Scorpius - Antares. Antares is a red giant, the size of which dwarfs our own sun. It’s so gigantic that if you place it at the centre of our solar system, it would engulf Mercury, venus, earth, mars and even Jupiter!

(The data was acquired from Telescopelive, which I processed using pixinsight and photoshop).