TWN meteorologist's amazing astrophotograph of stellar nursery goes viral

The Cocoon Nebula IC5146, taken on August 24, 2014, by TWN meteorologist Kerry-Ann Lecky Hepburn. Source: www.weatherandsky.com

Monday, October 27, 2014, 11:46 AM - Not many people can say that having a nemesis has paid off particularly well in their life, but if you ask Weather Network meteorologist Kerry-Ann Lecky Hepburn about her own personal nemesis - the Cocoon Nebula, pictured above - she'd probably say that things turned out pretty well, overall.

The Cocoon Nebula, also known as IC 5146, is an immense cloud of dust and gas, roughly 140 trillion kilometers from one edge to the other - so large it takes 15 years for light to travel across it. It is, essentially, a stellar nursery for a cluster of some of the youngest stars in the Milky Way Galaxy. Our own Sun, which is 4.5 billion years old, is considered to be a 'middle-aged' star, as it has roughly 5 billion years of 'life' left in it. The central star in the Cocoon Nebula - a blue star named BD+46°3474 - is only 100,000 years old, which, if we plotted those ages on a human lifespan of 100 years (a little generous, but easier for calculation), that would mean that it was 'born' just shy of 9 hours ago!

According to Phil Plait, of Slate's Bad Astronomer, who posted the amazing photograph on his blog early Monday morning, the star may be young, but it's huge!

"It’s a beast," he wrote, "five times the diameter of the Sun, 15 times its mass, and a brutal 20,000 times as luminous. Replace the Sun with BD+46 and the Earth would be a smoking ruin."

The nebula itself is considered a 'reflection/emission nebula', since the dust in the cloud both reflects the light from the stars within it, but it also absorbs some of the light and emits its own light as a result. As it's a particularly remarkable object, British astronomer Patrick Moore included it in his list of Caldwell Objects - one of 109 objects out in space that were gathered together as being prime viewing targets for amateur astronomers. As such, it was a natural target for Hepburn to pursue. However, she names it as her nemesis because it has thwarted all of her previous attempts to capture a good astrophotograph.

That changed on August 24, 2014, when she completed her latest attempt and posted the results on her website.

"My previous versions were taken with an unmodified Canon 40D and it was very difficult for me to tease out much detail or depth," she wrote (and cross-posted on Google Plus). "This version, now revisited with a cooled CCD, has really opened my eyes to what's out there in this part of the sky."

Whereas the Canon digital camera she was using was a very nice one, a cooled CCD is much better for something as detailed as astrophotography. CCDs (Charge-Coupled Device) represent the most light-sensitive detection method we have today, and are used on telescopes like the Hubble Space Telescope and the Kepler Space Telescope, just to name two of the more famous (and amazing!) examples. Perhaps the most incredible part of this is that Hepburn didn't need to use a major telescope to capture this photograph. She gathered exposures of it using an 8-inch reflector telescope, from her SkyShed Observatory, right in the front yard of her home in Ontario's Golden Horseshoe region!

To see more of Hepburn's photography, which includes incredible astrophotographs, amazing pictures of storms, clouds and auroras, and an array of cool scenic and still life images, go to her website, www.weatherandsky.com.

(Tip 'o the hat to Phil Plait)