Thursday 7 January 2016

NGC2174, the Monkey Head nebula

You may find it odd that I want to publish a sketch of this unknown nebula as one of the first posts on this blog. Let's say that I want to rectify a big injustice. In all honesty, I have to plead guilty as well. I can count the times that I've visited this nebula on the fingers of one hand, even though it has all that it takes to be an all-time favourite: it's very easy to find, just south of èta Geminorum, it's bright enough to be observed in nearly every telescope and if you take a good look it easily reveals a myriad of filaments and details. And to top it off it has a funny nickname derived from its particular shape. So what more do you want?

But first, let me tell you something more about this peculiar object. The Monkey Head nebula is an enormous cloud of gas (mostly hydrogen) and dust heated up by incredibly hot and young stars within its heart to the point that it begins to emit light itself. In fact, this nebula is a gigantic star nursery! The light and winds from the newly born stars disperse the gas clouds in which they were formed and in the next millions of years these stars will leave the nursery to find their own way in the universe. It's perhaps not as famous as other nebulas in which stars are born such as the Orion or Lagoon nebulas, but nevertheless it's spectacular in its own right. It's 6.400 lightyears away from us (much further than the Orion nebula at 1.340 lightyears) and covers an area in the sky almost as large as the disk of the full moon. But unfortunately it's too faint for the naked eye so don't get overexcited. Please also note that the bright star at the centre of the nebula doesn't belong to the nebula at all but that it's a lot closer to us (994 lightyears). So you see that looking at the night's sky can be very deceiving. Similarly, the stars that form the various constellations have in reality nothing to do with each other and may often be thousands of lightyears apart. A popular example of this are the three stars of Orion's belt. In our sky they really look to belong with each other. In reality however, the left star is 817 lightyears away, the right one 916 lightyears, but the middle one... 1.976 lightyears!

For my drawing I used UHC filters which block most of the light, apart from the specific frequencies emitted by the nebula. This makes the background darker and also the stars, which emit light in all frequencies, look a lot fainter. This, however, creates a lot more contrast with the nebula and therefore it becomes visible more easily. The moment it entered the field of view of my binoculars it immediately leaped out at me. When looking more closely in my Nexus 100 at 24x, several details became easily visible, such as the "eyes" and "mouth" of the monkey's head. 

I sincerely hope that this post may incite others to visit this nebula too. It truly deserves a bit more attention.




No comments:

Post a Comment