Category Archives: Astronomy

Discovery 12.5 Dobsonian: Initial Thoughts

Discovery 12.5″ at its new home – many new
deep sky explorations await!

When I poked my head out this morning I almost didn’t get up because it looked a bit foggy and there was a halo around the moon indicating a good bit of humidity in the sky… And even a few wisps of clouds. But I had not yet had a chance to look at Jupiter with the new scope so curiosity got the best of me. I was up late last night working on a list of double stars so when I went to bed I did so in all my cozy layers. All I had to do was slip on my boots, a hat and my coat. I grabbed two eyepieces and stepped out the door.

The scope and everything around it was with coated with a thick layer of frost. 19 degrees this morning but, thankfully, no wind. There were birds though, lots of chirpy birds. And a very pretty sunrise. And Jupiter which you don’t see in this picture because the gas giant was out of the range of the photo, just a pinpoint of light high in the western sky. To the untrained eye the largest planet in our solar system would have looked like a star about to fade from view in the brightening sky.

I’m glad I got up when I did because had I waited another 15 minutes I might not have found it. As it was I had just enough time to tilt the scope over and place the Tetrad’s red center point on the fading pinpoint. I was treated to the best view of Jupiter I’ve ever had. Even with the coming daylight I saw three bands of reddish clouds stretching across the white sphere of the planet. The two main bands even hinted at a bit of detail along the edges which exhibited irregularities. Even more,  the white base color of the planet turned into a gradient of a fainter red over the north and south poles. Four moons were easily visible as pinpoints of light.

For a little treat after Jupiter I swung over to the moon (top right corner of the photo) and in its current crescent stage it’s possible to see many more craters along the edge and it was a fantastic view.

This marks the 5th viewing session with the new scope. Well, new to me. It’s actually about 14 years old. Handmade by the folks at Discovery Telescopes, it was a chance find on Craig’s List. With a mirror of 12.5″ it’s only slightly larger than the Zummel’s 12″ mirror. I am not at all unhappy with the Zummel and have enjoyed it a great deal over the past three years but this was a chance at a better scope and thus a better visual experience at a good price so I went for it. Not only are the optics better but it came with an equatorial platform for tracking objects in the eyepiece. So, what are some of the differences and how does it perform?

Most importantly, the Discovery scopes are built with hand-made mirrors that are a step up from mass produced mirrors used in scopes by Zummel, Orion and others. Or so it is said. In terms of the visual experience I have to also mention that the Discovery is built using cardboard Sonotubes. Yes, cardboard. Very well painted and the Sonotube is very, very sturdy so this is not something that will bend or break easily as long as it is taken care of. But most importantly, the interior of the tube is pitch black. Unlike an unflocked metal scope that’s been painted black but appears gray this is completely black. Set this next to the Zummel on a dark night and you’d be amazed at the grayish blue glow that you see when looking down the tube of the Zummel. Look down the tube of the Discovery and it is pitch black. The only light to be seen is that being reflected back up by the primary mirror at the base of the tube.

The result of the improved mirror and the blackened tube in the eyepiece is not just noticeable but dramatic. I can’t say for certain how much of the improvement is the mirror and how much is the darker tube but I can say that in the five sessions I’ve had I am thrilled. As mentioned above, the view of Jupiter this morning was the best I’ve ever had. Did I think my views before were lacking? At the time, no. I was always very happy with them. But it is greatly improved with this scope. I’m looking forward to more viewings with darker skies and greater contrast.  I suspect that for the most part the views will only be better.

Another object I’ve viewed during four of the sessions that needs special attention is the Orion Nebula. WOW. The view with this scope is nothing short of spectacular. When viewing astronomical objects, especially nebulosity, the key is contrast which translates into increased detail. With such low light the observer is always looking for the subtle details to be found in gradients of gray and usually blueish light. So, in an object such as the Orion Nebula which is easy to see even in binoculars the details emerge as you improve your practice viewing and as you observe with better equipment. I’ve had a good bit of practice and am seeing more all the time just because I’ve been looking at it now for 3+ years with several different scopes. In some ways it’s like other visual activities that one learns in practice.

For example, as a bird watcher I’m still learning new things about birds and learning how not just identify them but to really see the details. With birds it’s everything from the shape of the beak to the colorful feather markings, the shape of it’s body, to the way the bird flies and more.

In visual astronomy practice helps one to see more details in any instrument but it also helps one notice the refined details in better instruments. If I were to look at the Orion Nebula with my 8″ scope now I would see more than I did 3 years ago when I first looked using that scope because I know how too look. I know about averted vision and about spending enough time on an object. I know more of the details and about looking at dark areas as much as the light areas. So, regardless of instrument the view is always getting better with practice and familiarity. But with the Discovery I can safely say that I am seeing an amazing amount of new detail. The increased contrast means the subtle details that would have been lacking before now stand out. Differences in color and brightness mean differences in gradient which, in the case of this particular object, means a new sense of visual depth, of dimension. Honestly, this wasn’t something I was expecting. Yes, I was hoping for a better view, better detail, but I didn’t quite understand what that would be. Now I know.

Viewing the nebula now means seeing new detail everywhere which leads to this added sense of dimension. It’s no longer a flat view. Now, I expect not all objects will benefit in the same way. In fact, I know they will not. My view of the Crab nebula is improved but not by much. It is a much dimmer object to begin with and as I understand it details only emerge with scopes larger than 16″. I can’t say that’s true but I can say that my view is largely the same with all three of the scopes I have at my disposal: 8″, 12″ and the 12.5″. In all three it is an irregular, somewhat spherical gray nebulosity that offers little to no detail. But M82, one of the two Bode’s galaxies?  I’ve not had nearly as much time with M82 with the new scope but in the brief time I’ve had I’d say it is improved a good bit. It might not prove to be as dramatic as the view of the Orion Nebula but it’s definitely better. The same for the Andromeda Galaxy and the Triangulum Galaxy. My expectation is that objects such as galaxies that can offer a view of spiral arm structure will benefit a good bit which is great because they are some of my favorite objects to view. Some nebulae will be improved, others won’t. I doubt larger open clusters of stars will be improved but I suspect the resolution of some of the fainter stars in some open clusters will be as will some globular clusters.

Viewing Comet Lovejoy

We finally got a chance to take advantage of the clear, moonless skies to have a look at Comet Lovejoy! Farra, Atira, Kaleesha joined me at the scope and it was quite a view. Fantastic I’d say. We also had a look at a few objects that Farra had not had a chance to see yet: the Andromeda Galaxy, Orion Nebula and the Starfish Cluster.

Homeschool Star Party

Wow. Just had a crowd of homeschool families from Poplar Bluff over for a star party. Denny manned the telescope, Farra helped guide the way up and down the path in the dark, Atira and Seth helped me in the house, making popcorn and hot cocoa and directing folks to the bathroom. I also quizzed the kids when they came in about what Denny had shown them. A wee bit hectic overall, as there were more than we were expecting, but quite a fun way to spend a winter’s evening.

The Milky Way Reflected

Stunning image of the disk of our Milky Way galaxy: 200 – 500 billion other stars just in our galaxy which is one of billions of galaxies. Fantastic!The bulge you see at the center is the actual center of the disk and contains a super massive black hole and is 26,000 light-years from our Solar System, in a region called Sagittarius A. It is estimated to be 4.1 million solar masses.The two patches of light to the left of the middle are the Magellanic Clouds, two nearby dwarf galaxies that are gravitationally bound to our Milky Way.

 Original, high res version here: http://apod.nasa.gov/apod/image/1409/AtacamaSaltLagoontudorica2320.jpg

Our Star

Fantastic image of our local star! Absolutely stunning.

The diameter of the Sun is about 109 times that of Earth, and it has a mass about 330,000 times that of Earth, accounting for about 99.86% of the total mass of the Solar System. Chemically, about three quarters of the Sun’s mass consists of hydrogen, whereas the rest is mostly helium, and much smaller quantities of heavier elements, including oxygen, carbon, neon and iron. 

The Sun is a G-type main-sequence star (G2V) based on spectral class and it is informally designated as a yellow dwarf that formed approximately 4.567 billion[b] years ago from the gravitational collapse of a region within a large molecular cloud. Most of the matter gathered in the center, whereas the rest flattened into an orbiting disk that became the Solar System. The central mass became increasingly hot and dense, eventually initiating thermonuclear fusion in its core. It is thought that almost all stars form by this process. The Sun is roughly middle age and has not changed dramatically for four billion[b] years, and will remain fairly stable for four billion more. However, after hydrogen fusion in its core has stopped, the Sun will undergo severe changes and become a red giant. It is calculated that the Sun will become sufficiently large to engulf the current orbits of Mercury, Venus, and possibly Earth.

Rhubarb and Sam, Episode 4

This week in Rhubarb and Sam, astronomy! We set-up at the Tucker Creek observatory for some time at the telescope only to have a clear night turn into a not-so-clear night due to high humidity. The stars were still pretty bright in our dark skies so we settled in on the moon couch (our disc shaped outdoor couch) to record an episode. From Cygnus to Sagittarius, Saturn to Mars, take a tour of our night sky with us. There’s nothing quite like pondering our place in our galaxy and our galaxy’s place in the Universe. Have a listen!

Links of interest:
Our Milky Way Galaxy 
Our Solar System 
Globular Clusters

Please note that you can subscribe to the podcast in several ways:
At the iTunes store via this link.
If you are using an RSS reader or podcast app use this link.

Thanks and enjoy!

Wonderland

There are moments in life when everything feels just right. I’m not sure if those moments are happening all the time and it is just a matter of seeing them, recognizing them and acknowledging them or if it is the act of recognizing the potential of their existence that we help them into existence. Whatever the case may be, I feel fortunate to have chosen a life, created a life, in which such moments seem to come often. If I had to guess I suppose I’d say that such moments become more numerous the more we are able to slow down, the more we are able to be in the moment with those around us. We had such a night tonight here at Make-It-Do.

Dinner was unusual in that I missed it. We always make it a point to sit together for every meal. All of us. But tonight I slept through it because I’d been up late at the scope and because we had a long day in the car which left my back aching. I napped until Kaleesha woke me after six. By that time the kids had gone off to play in the woods. Kaleesha had made the two of us salads for dinner so we sat on the back porch to eat. The sounds of life went on all around us. The chickens and goats were doing their thing and off beyond the goat yard the kids were at the edge of the woods playing. So many sweet sensations all mixing together: the wonderful food, the cool and unusual July temperature, the sounds of children and farm and conversation between the two of us made for a wonderful start to the evening. Shortly after dinner we were separated for a bit as she took a call from her mom and as she often does while chatting on the phone, wandered around the house taking care of little chores. She took care of the bread dough she’d started before dinner and, not long after, she put the rising loaves into the oven the smell of fresh bread filed the house. The kids continued to play in the woods so I picked up my book on the Herschel Objects and started reading, alternating between the book and a few articles on the iPad. At some point I got up for a bit of coffee and decided to hang LED string lights on the back porch. It’s something we’d talked about doing just the other day in preparation for company coming Thursday night, so I thought I’d go ahead and get them up. By the time I’d finished the task the sun had settled in behind the trees and the kids had returned from their time in the woods. There’s nothing quite as sweet as these kids telling the stories of such evenings. They described the work they’d done in cleaning a little patch of woods they sometimes play in and showed me the fresh callouses on their hands. They were excited and very pleased with themselves.

The bread was out of the oven and I was having another mug of coffee when we’d decided it was dark enough to get everyone ready to walk up the hill to the observatory. We’ve not taken much time to get everyone up here for viewing since we built the observatory. Mostly that is due to the seemingly never ending streak of cloudy weather which has meant observing time has been scarce. In recent days a couple of the kids have expressed a desire for scope time, so we jumped at the chance to share a clear night with them. As an amateur astronomer one of the greatest joys is sharing the beauty of the Universe. There’s nothing quite like the reactions one hears when someone sets their eyes upon Saturn or the great globular cluster of Hercules or any number of other beautiful objects. Sharing it with kids is even better.

The Tucker Creek Observatory.

By the time we’d gotten the scope out it was just starting to get dark and Saturn was low in the horizon so I started with the beautiful ringed planet. Justin had the first turn and he seemed more interested than he’s ever been. Most people, kids included, usually don’t keep their eyes at the eyepiece long enough. I’ve noticed the same thing whenever I’ve taken a walk in the woods with others. More often than not, such walks seems to be a race to finish the walk with little time taken to really observe the details of everything on or near the trail. I suppose I’m not surprised. Our culture seems to emphasize quantity over quality, passive consumption over authentic engagement. This is a mistake, especially when it comes to amateur astronomy. Objects in the night sky are much better when viewed for a length of time. Our eyes take time to adjust to the dark and even after they are dark adapted more time looking through an eyepiece almost always allows for our brains to notice fine details.

Justin took his time. In fact, he seemed to be in no hurry at all as he focused on the planet.

“Do you see it Justin?”

“Yep.”

The scope moves easily and he has a tendency to bump in when he leans in, so I got on the ground while Kaleesha helped him at the eyepiece. From the ground I could look up the tube to the center red circle and keep the planet where it needed to be. Every 20 seconds or so we repeated the question to make sure he still had it in his view and each time he responded with “Yep.” He looked far longer than any of the other children; probably 2 minutes, maybe more. He was very attentive. Finally he pronounced, “Royal’s turn!” and moved away from the scope. The kids all cycled through their turns at the scope, most of them offering some sort of excited acknowledgment of what they were looking at. From there we moved on to Mars which was just off to the west of Saturn. Royal requested that we look at the beautiful blue and gold double star Alberio in Cygnus. He remembered it from our very first time at the telescope in November 2012, so we moved to that next. From there we moved to the Ring Nebula and last the M13, the Great Globular Cluster in Hercules.

The Ring Nebula image similar to that viewed in
our 12″ telescope. Our view has less color.

The Ring Nebula, while not too flashy in the telescope, is a beautiful sight nonetheless. As with most astronomical objects the beauty is enhanced if some of the details are known. At the core of the nebula is a white dwarf star consisting of carbon and oxygen. Its mass is about 0.61–0.62 solar mass, with a surface temperature of 125,000±5,000 K. Currently it is 200 times more luminous than the Sun. Keep in mind that this is a star which is no longer in active nuclear fusion. It has exhausted its fuel and blown away the remaining gasses which form the ring nebula we see. The star is now just radiating heat and it is thought that such white dwarfs will do so for trillions of years. Source: [Wikipedia]

In contrast to the subtle beauty of the Ring Nebula, the Hercules Cluster, M13, is quite a sight and one of our favorites. Here’s why:

Messier 13 contains several hundred thousand stars; some sources even quote more than a million. The brightest is the variable star V11, with an apparent magnitude of 11.95. Toward the center of M 13, stars are about 500 times more concentrated than in the solar neighborhood. While the probability of collisions between stars in such a crowded region is negligible, the night sky seen from a planet near the center of of this globular cluster would be filled with thousands of stars brighter than Venus and Sirius!

Unlike open clusters, such as the Pleiades, globular clusters are tightly bound together by gravity, and contain very old, mostly red stars. The age of M 13 has revised to 12 billion years – nearly as old as the Milky Way galaxy itself. Born before the Galaxy’s stars had a chance to create metals and distribute them them in its star-forming regions, M 13’s iron content relative to hydrogen is just 5% of the Sun’s.

Source: Sky Safari App.

M13 as it appears in our 12″ telescope.

It is a sight to behold. As the kids took their turns at the eyepiece on this last object I explained what they were seeing just as I had for the other objects. Justin, upon looking at the cluster simply said, “It’s a galaxy!” We corrected him, knowing that while he may not understand the difference some of the other kids, Little Brook, Royal and Blue would likely pick up on it and would likely have a better understanding of the difference. There’s something extraordinary about taking our time to explore the Universe with one another, especially when children are involved. Whether it is a globular cluster or a tiny frog, they are intensely curious. I continue to be amazed by the details they pick up on and the amount of information that they retain. While the youngest may not fully understand the difference between a galaxy and a globular cluster they certainly retain the information that they are different.

Just as exciting as our shared explorations is that they are actively investigating on their own time. The other day Little Brook saw a photo of a nebula as the kids were browsing through one of our astronomy photo books and excitedly proclaimed “That’s the Horsehead Nebula!” This was something that she had learned on her own. Imagine a five year old learning to identify the Horsehead Nebula! Sometimes all I can do is shake my head and smile. As I sit typing this there are 3 day old ducklings happily chirping as they follow their momma just 10 feet outside my window. One room away Farra is working on some chain-mail armor and Blue and Little are speaking in very well done British accents as they play on the porch.

Yeah, I live in Wonderland.

Lunar Eclipse

Here’s another, slightly better, shot of last night’s eclipse. I tweaked this one just a bit to bring out the details. The stars visible in the scope (not photo) right to the edge of the moon offer up amazing perspective and sense of dimension. This kind of event is the only time we get to see such a large, normally bright object, in such a way as to also see distant space objects in close visual proximity. A real treat!