Meditation Under The Stars

I'm way behind posting "normal" stuff on the blog, but forgivable after the loss of a spouse... Twelve days after Melinda's passing, buddy Roger offered to get me out of the house for an observing session. I jumped at the chance, not only to get under some dark sky before the moon became objectionable (this was over 2 weeks ago) but also because Melinda loved her time under the stars too. With the Summer Milky Way now moved to the western sky, it was about the last time this observing season to spot some favorite Milky Way objects.

Interestingly, I've not taken any images of Messier 16 other than a snapshot or two. Made up of both clouds of dark matter, as well as an ionized glowing hydrogen cloud, it forms the outline of a bird, thus its alternate name of the Eagle Nebula. Just don't ask me to show the eagle, I frankly don't see much of one... Shown at left is virtually the entire frame with the TEC 140 with the full-frame sensor of the Canon 6D - theoretically about 2 degrees across! The wisps of red (ionized hydrogen clouds!) show how extensive and large this object really is.

What is really of interest in this object was brought to attention by an early image from the Hubble Space Telescope. Dubbed, the Pillars of Creation, the image was collected in April of 1995, it has been rated as one of the top ten images from the Hubble. It shows an area where the clouds of dust and gas have collected into new stars, and the radiation pressure is shaping the clouds, likely starting the formation of more. Looking at my full-resolution enlargement of the Pillars (above right), they are easily made out in this shot representing 32 minutes of exposure with the 5.5" diameter telescope.

More interesting to me is that I see lots of "sharpening" artifacts around brighter stars, seen in a further blow-up of the central part of the nebula at left. Those dark circles (and some bright ones) should not be there - they normally appear when an image is over-sharpened and to my knowledge none has been applied outside of the camera. I'm still looking for the cause of these artifacts...


After spending time imaging a dark nebula seen in silhouette against the stars of the Milky Way (that didn't come out as planed), I next went to a planetary nebula, whose unromantic name is NGC 7293, otherwise known as the Helix Nebula. While readily visible in binoculars, it was not spotted by Charles Messier in the 1700s, thus has no "M" number like many other bright objects do. But it is quite amazing in a telescope as a large ghostly donut in the sky. Don't forget, the colors you see in these images are NOT visible to the eye even in a large telescope, so this large object appears only in shades of grey. This object is what is called a planetary nebula. Back when the planets Neptune and Uranus was discovered, they displayed greenish-blue disks, as do some of the smaller planetary nebulae. We now know they are the remnants of old stars that blew off part of their mass into these shells of gas as they run out of fuel to continue thermonuclear fusion in their interiors...

My next target as I continued to work eastward in the sky is another southern-sky object, NGC 253, one of the brighter and spectacular galaxies in the sky. Like the Helix, this one is also visible in binoculars, but is truly striking in a largish telescope. Here at left is a close-up of the galaxy, 14 minutes of total exposure. Its distance of 11.4 million light years puts it about 5 times further away from our nearby big neighbors M31 and M33 in Andromeda and Triangulum, but it is still amazing to observe or photograph.

The other reason that I shot it is that it is near, almost adjacent to NGC 288. The pair is shown at right in a 3-frame mosaic. Of course, as most things astronomical, just because they appear near each other doesn't mean they are together in space! The cluster is about 28,000 light years away, only about one quarter of one percent the distance to NGC 253! Of course, the individual stars you see here are also in our own Milky Way Galaxy, just like the cluster - just like the Helix Nebula and M-16 further up in the post - all inside our own galaxy except NGC 253...

The last shot was almost an afterthought. Usually on the last shot just before putting things away, I shoot a few frames on something I might not normally shoot just to see how it comes out. Here I shot the Pleiades star cluster in Taurus - 6 frames totaling 16 minutes of exposure. The cluster is a young one that happens to be passing through a dust cloud about 440 light years away. The dust cloud structures certainly add a striking appearance to the cluster, which has about 1000 stars in it. The cluster formed out of a cloud of gas and dust about 100 million years ago and formed not only the bright stars seen here, but multitudes of lower-mass (and faint) stars too.

Well, that was it, a long night by our standards - home by about 3:00 in the morning. Surely a long night, but it is always fun to spend time under a dark sky...