NEBULAE
They are clouds of gas and dust in outer space that look like cloudy patches of light. The main types are planetary nebulae, emission nebulae, dark nebulae and super nova remnants. What makes nebulae a photographer’s paradise is not only their visual appeal, but also the camera’s advantage over any other equipment in capturing the details and colours of nebulae.
The human eye registers what it witnesses instantly. Therefore, even with a telescope you will only see pale greenish-yellow cloudy patches of light. On the other hand, a camera allows for longer exposures and can therefore capture a nebula’s true beauty with its varying hues and shades.
Horse head Nebula gets the name from its resemblance to a horse’s face. It is a dark nebula containing patches of dust, which blocks light coming from behind. The diffuse nebulosity behind it creates mysterious patterns, making it a real pleasure to look at.
Visibility: Best between 3:00 am and 5:30 am.
Lagoon Nebula is an irregular figure with a large star cluster. A mix of dark and emission nebulosity, gives this nebula its black areas and reddish colours.
Visibility: Best between 8:00 pm and 2:30 am.
Crab Nebula is a supernova remnant, which occurs when a star blows up, as this one did when it was observed by the Chinese astronomers in 1054 CE. While the outer layers of gas from the explosion of this dead star continue to expand and cool, the inner core collapses into a pulsating, x-ray emitting neutron star.
Visibility: Best between 2:30 am and 5:30 am.
Trifid Nebula is an unusual combination of an open star cluster, an emission nebula lending it the red colour, a reflection nebula creating the blue light and a dark nebula which gives it the dark diffuse characteristic. Interestingly, the combination creates a beautiful image as a whole and also allows individual characteristics and colours to stand out.
Visibility: Best between 8:00 pm and 2:30 am.
Ring Nebula in Lyra is a large and bright ring shaped structure, with a faint central star. This is one of the finest and brightest planetary nebulae in our Milky Way galaxy.
Visibility: Best between 8:00 pm and 3:30 am.
Cone Nebula and Christmas Tree Cluster are seen as one astronomical object. The former has an inverted cone shape created by a combination of dark and emission nebulae. The tip of the cone is where the inverted christmas tree cluster starts.
Visibility: Best between 3:30 am and 5:30 am.
Dumbbell Nebula also called Apple Core Nebula, has the largest white dwarf star in the centre, when compared with any other planetary nebulae.
Visibility: Best between 8:00 pm and 4:30 am.
Elephant’s Trunk Nebula is a bright nebulous part of our Milky Way Galaxy.
Visibility: Best between 9 pm and 5:00 am.
Saturn Nebula is a small elliptical planetary nebula that looks just like the planet Saturn with its rings.
Visibility: Best between 8:00 pm and 5:00 am.
Great Orion Nebula is a magnificent nebula with Theta-1 Orionis and is probably the most popularly known nebula of all. It is an active region of star formation and has some of the youngest stars in our galaxy.
Visibility: Best between 3:00 am and 5:30 am.
Viewing Equipment: Nebulae are usually not visible to the unaided eye, but easily visible with a good pair of binoculars and best with wide field telescopes. To capture the colours you can use DSLR cameras attached to a telescope. Film cameras with fast film (200 ISO and above) need an exposure of 10 to 20 minutes or digital Charge Coupled Device (CCD) camera sensors need an exposure of 2 to 10 minutes depending on the sky conditions and brightness of the object.
All images courtesy NASA.
To know about spectacular galaxies you can spot this month click here