The Cheapskate in me Comes Out!

Some of you saw my new telescope mounting a few weeks ago and found something definitely non-standard about it!  The photo at left shows it.  While I got a good deal on the mount, the owner kept his pier, counterweights and saddle plate for his new mount - I was on my own to replace them.   Fortunately, Dean Koenig of Starizona knew a machinist to make me 2 piers (!), one for my C-14, a tall version, and a shorter version for a Newtonian telescope.   I decided to go to Astro-Physics for the saddle plate.  But for the counterweights, I drew the line.  AP wanted big bucks for stainless steel weights - and really, they are just weights!  You could hang a toolbox off the end of the bar, as long as it balanced the tube assembly across the right ascension axis...  I tried to find a less-expensive alternative.  The weight by Roger's left hip is the result!

After looking at a couple options, I decided to take a Mirror Lab engineer's advice and get some regular steel water jet cut to rough shape, so that it took minimal machining to clean up.  And while the AP stainless weights were pricey, I copied their design by lining the hole with brass so it wouldn't scratch the stainless declination axis on which they mount.  There would also be a brass pin that is pushed by a screw to tighten it on the shaft - which also wouldn't scratch the shaft. 

While I don't consider myself a machinist, I can use most of the equipment in our little machine shop at work in a pinch.  There wasn't anything complicated about anything here, and it adds a little to the satisfaction I'll get when I use it.  The lathe is a little wimpy - it has a loose drive belt and won't take much of a load, slowing down the process some, but that is ok. 

Here are the steps I used.  First, I had some 6.125" circles water jet cut out of some 1" and 2" thick steel plate at A-1 Fabrication here in Tucson.  That step also included cutting a 1.875" hole in the center.  I figured that would come out to about 90 pounds of counterweight, which should balance about  120 pound load on the mount - well within its capacity, and more than all the telescopes I currently own.  The rough-cut disks are shown at left.  The first step is to grab it by the center hole and turn the outside diameter.  The machine marks cleaned up enough for me to stop at about 6.050" OD.

 

 

Next was to grab it by the OD and open up the OD to 2.00", which matched the OD of a piece of brass tubing I bought to line the ID.  Given that I'm new to machining steel, the surface roughness and accuracy of the lathe prevented a super-accurate fit, so after machining to a few thousandths of an inch, I cut the brass tube to the right length.

 

 

Since I couldn't do a true "pressed fit", I did the next best thing and glued the brass insert in place using J-B Weld to permanently hold it in place.  After an overnight cure, and machining the excess brass down to the steel dimensions, it was time to mount the locking screw and pin.  First step was to bore the right size hole.

 

 

The hole size is the correct hole for tapping a 3/8X16 threaded hole for the locking screw.  It helps to get the tap started using the drill press so it is perfectly aligned.  Then you loosen and back off the chuck and finish the job by hand.

 

 

Then it is time to trim down the brass rod I bought to the right diameter to fit the tap hole that i drilled in the weight.  Cut it to the correct length so it barely extends into the hole with the screw tightened down and you are done!  I can process a single weight in about 1.5 to 2 hours of after-hours activity, and am currently about half through my pile of weights.  Since these are regular steel that will rust, I'll likely sandblast them, prime and paint them before considering them finished.

 

So how much did I save?  Well, AP doesn't make 7 or 15 pound weights, but interpolating from the 5, 10 and 18 pound weight they do make, my weights would have run about $1150.  For this project, my water jet steel cost $550 for material and cutting, and my brass tubing and rod cost another $50 for a total of $600 - so about half price from the commercial version.  Of course, I should add something for my time, but as a hobbyist, it is hard to justify doing that, plus I had a little fun and some learning along the way.  Given what I've learned about how long it has taken for me to do the work, I'd think harder about repeating the experiment, but since I saved some money, I'm glad I did it!

Beaver Fever!

We're visiting the Midwest again for our "mid-holiday visit".  Compared to travel during Thanksgiving or Christmas, or even our standard, random times of the year, the period between the holidays is pretty slow and quite pleasant with empty seats on the plane.  So we're enjoying the Christmas lights around town and spending time with family for a few days.  For a little excitement and a gift for "Auntie Maj", we brought along our cat Annie, who spent her first few years living in our Illinois house.  Once we caught her (a real adventure!), the rest of the trip was uneventful, and she enjoys being the only cat in the household with unlimited attention from us, but rarely expresses much interest in the world outside the window or the birds and squirrels there.

I took a walk down along the river this afternoon and didn't expect to see much in the way of nature, and sure enough, lots of browns and greys, but without the accent of any white snow yet, although sister Kathy reports they got a dusting 3 hours to the west of us.  A friend we shared dinner with last night - an organic farmer, stated that after today we're setting a new record for consecutive days without snow at 280 days!  Perhaps a sign of global warming, since the record being broken is only 8 years old!

But something caught my eye - about 400 meters upriver, it looks like we've got a localized beaver infestation!  I've blogged before about seeing some signs of beaver, in fact, it was exactly 3 years ago.  But today there was a good-sized sapling about 6" diameter that was felled across the trail, and about 10 smaller saplings that had been cut and removed.  I didn't see where they had been moved to, a few trees that small wouldn't have had much effect on the Fox River, nearly 150 meters across at that location.  A Google search for "beavers in Kane county" only brought up pest-removal companies (no adult sites like Melinda's dirty mind concocted!), so they must be proliferating, which I'm all in favor of...  At left is a mini-panorama of the new clearing they are making, with a close-up at right with fresh shavings.  Below is a cross-eyed 3D view - cross your eyes slightly to fuse the stereo images...  Would be cool to see real-live beavers - will keep an eye out for our remaining days here!

Earliest Sunset!

Here we are on the 5th of December, a good 2 weeks till the Winter Solstice, and yet, if you look at a table of sunset times, right now is the time of earliest sunset!  "Wait", I can hear you all say - "I thought that happened on the first day of Winter on 21 December!"  Well, you would be partly right - the shortest DAY occurs on the first day of Winter in the northern hemisphere, when the sun follows its lowest arc across the sky.  Referring back to that table of sunset/sunrise times, you will also note that the date of latest sunrise occurs in mid-January, a couple weeks AFTER Winter Solstice.  So the shortest day happens on 21 December, but because the Earth's orbit is not completely circular, but slightly elliptical, the earliest sunset, latest sunrise and shortest day do not all fall on the first day of Winter.  If it did, life would be a little more boring, and we wouldn't be able to use these tidbits as excuses to learn something new.  But do go check out those sunrise/sunset times - you will see I'm right!  You can think of it this way - with the sunset time getting later day by day, it won't be long till the Winter that isn't here yet will give way to Spring and Summer!

 

Oh, and the picture above - taken a couple months ago from Kitt Peak National Observatory with my little Meade Telescope - an 80mm diameter apochromatic refractor, F/6, with a 480mm focal length and Canon XSi camera.

A Tall Tale Turns Out True!

My friend David Levine (shown here at left with wife Elinor at McDonald Observatory) was a buddy of mine from the local astronomy club, the Tucson Amateur Astronomy Association.  We shared similar interests, which included setting up for many public events, including the Grand Canyon Star Party, as well as more serious observing from TAAA dark-sky sites.  He had a way of telling a tale that was sometimes difficult to tell if it was true or not.  I could usually tell by the twinkle in his eye, but in the dark, it was harder to tell.  The Horsehead Nebula in your 8" telescope - Sure (wink-wink), I can believe that!  One of his stories involved observing a shadow transit on Jupiter, where the normally round shadow of the moon was crescent-shaped!  He was short on details, but indicated it was close to opposition when Jupiter was opposite the sun, rising at sunset, and the moon itself was blocking part of it's shadow.  Well, I had never heard of such a thing, and I've been around the block a few times, but he swore it was true!

Well Dave died a few years back but that tale has always stuck with me, and it just so happened that early yesterday Jupiter was at opposition.  Looking at a Javascript for the moon positions, it happened that Europa had a shadow transit about 6 or 7 hours past opposition - time for an adventure!  Since I work at Kitt Peak part time at their Nightly Observing Program, I was able to reserve the telescope for after the program.  There was a bright moon, so little demand for a late-night program.  Unfortunately, the shadow transit didn't start till after 2am local time - hard for a school night, but hey - these myths need to be dispelled!  I packed my webcam and laptop and headed to the Observatory after my wife left for her NICU shift.

It was a great, clear night and better-than-average seeing given the blustery breeze that was blowing.  I spent a couple hours trying some wide-field images in the moonlight, waiting for Europa to move into position.  Finally it was time to get set up - I've got little experience with the Imaging Source camera I got about a year ago, so it was a great night for some practice on the 20" scope.  The state-of-the-art of planetary imaging these days involves taking video sequences and taking the best images to stack into some truly amazing photos, and the camera/telescope combo worked well.  I took 2 minute sequences every 10 minutes or so and 3 of them are shown here.  At left Europa is shown approaching from the east and at right it is shown 20 minutes later as it casts it's shadow on the disk.

 

And some 70 minutes later, about the time I stopped with some thin cirrus moving in, the moon and shadow had crossed over halfway across Jupiter's disk.  The Great Red Spot had also rotated into view, and you can see a smaller red spot near the moon/shadow image.  Given the quality of the night, and that the seeing had deteriorated to about average, I'm amazed at how well these images came out.  And also, you can see that the disk of Europa indeed does occlude part of the black round shadow, a crescent shadow being the result - Dave was telling the truth!  A new observation for me, but I'm thinking that it has to be done within a few hours of opposition, and also, it will most likely occur for the inner moons Io and Europa.  I'm thinking the longer projection distance of the outer moons would make it more difficult to observe.  And yes, after disconnecting the camera and putting it away, I looked for seeing the partial shadow visually.  When waiting for moments of good seeing, yes, the crescent shadow could be seen, so it is possible to see with your own eyes.

 

Well, it was  long day at work after almost 3 hours of sleep, but it was a great adventure, and I'm glad to harken back to the old days sitting and talking astronomy with a dear departed friend.  The use of the 20" RCOS telescope is courtesy NOAO/AURA/NSF.

Something New, Different!

The Internet is a fun place, but it suffers from sort of a "sameness" when it comes to astronomy blogs.  I'm always searching for something that will draw me back time and again.  So it is always fun to find something new, my favorite this week is Astropixie, an astronomy and life interests blog from Australia.  She posts often and reading through the archives is a lot of fun - go check her out!  next time we update the "blogs we read" I'll be sure to get her up on those links.

One of the little links I found on an older post of hers was interesting - it brought to mind the link I found of Einstein at his blackboard where he would write whatever you wanted.  What, you don't remember that blog post?  Well, here it is in the original idea I had at the time - we put it on business cards once and passed them out whenever anyone wanted our e-mail or links to our blog when we set up at public events.  We've long run out of them, but would be fun to do it again - and yes, you can have "Uncle" Albert do your bidding by going to the website link on the image - and a variety of other images as well if you prefer...

 

Anyway, yes, the new link I saw - it is one where the message is written out by galaxy shapes!  The link, to My Galaxies, is written by Steven Bamford.  I believe he uses the Sloan Digital Sky Survey as source for galaxy images to use, and his routine allows you to try different images if the letters aren't clear enough for you, but it is kind of fun.  At left is one version of our blog address.  The website even identifies the galaxies used for the letters!  How often can you write someones name across the night sky - definitely something new and different!

Night Time Debut!

Last night was the grand opening of the "new for me" Astro-Physics AP1200 telescope mounting.  It is a big upgrade in the carrying capacity of the mount I've been using for the last 15+ years.  I obtained it from an acquaintance in the Chicago area this last summer when he upgraded to a newer model.  While the mount is in perfect shape, he kept some of the needed accessories, so I needed to obtain a new pier (machinist in Phoenix), saddle plate where telescope attaches (from Astro-Physics), and a new set of counterweights (water-jet steel from a local engineering company, machining by me!).  Finally all was ready to go, so with Roger C. in town, who made the 7" Apochromatic refractor about 10 years ago, we invited ourselves to the home of Richard Buchroeder to set up, and who took the enclosed pictures - thanks Dick!  At left, I set up the mount for the first time, and about the first time don't have an under-mounted telescope!  At right Roger critically checks out the view of the Moon at high power.

 

Besides the APO in front of the house, Dick also had a 5" APO that he designed for Meade Telescopes years ago in the side yard, and in the back yard had a 7" Maksutov telescope (also a Meade), both of which he recently obtained used.  So during the bulk of the 4 hours spent there, we circled the house checking out alternatively high-power views of bright stars overhead (it is what optics nerds look at!), what little terminator the nearly full Moon showed, and Jupiter a little later when it rose above Dick's trees.  Jupiter cooperated by having the Red Spot cyclonic storm rotate through the meridian for best viewing about 10pm - it looked great!  Of course, Melinda and our friend Donna are telescope fans too, and here are checking out the view of the Moon early in the evening through the Mak.  It was a fun evening - no need to leave town in search of a dark sky with the bright moon, and this way we got to have lots of viewing in a comfortable observing spot with refreshments!  In a few weeks when the moon passes, it will be time to search for darker skies and push the mount a little harder with the 14" Celestron and see how it performs with a heavier load.  Looking forward to it!

Thanksgiving Feast 2012

Yesterday was Thanksgiving, and even though we didn't host any family or friends like we usually do, we didn't hold back on the cooking!  We'd had a turkey taking up space in the freezer since I don't know how long (always hoping to smoke one during grillin' season).  And once you commit to the turkey, it snowballed into mashed potatoes, stuffing, gravy, veggies, brown-n-serve rolls, the works!  And while we normally would have stopped with a pumpkin pie, our house sitter and significant other were "stopping by for dessert", so I ended up making a chocolate cheesecake - normally only produced when we're giving most of it away like a potluck or other holiday party.

I had been running short on sleep lately, so as I slept in some on Thursday, Melinda woke at the crack of 7:30 and started making stuffing!  Here she is shown loading up the turkey cavity and giving the stuffed bird a nice butter massage...

Last week during grocery shopping, Melinda had loaded us up on Brussels sprouts, so we were looking for a new way to cook them up other than steamed.  In Joy of Cooking we found "Brussels Sprouts Cockaigne" (I don't know how to pronounce it either), where you brown up a few cloves of garlic in a few tablespoons of butter until it browns, remove the garlic, then cook the sprouts split side down till cooked.  They were quite tasty, though I'm sure loaded up with a lot more calories than steamed!

 

The turkey came out great, as did the stuffing.  But one of the highlights is always the Chocolate Cheesecake (again, from Joy of Cooking).  Here you can see Pixel overseeing the re-packaging of the cheesecake Thanksgiving morning, with Lucy studying the situation from below.  While yes, Pixel is allowed on the counter (at 16 years old, he has earned that privilege), he shows no interest in people food and regarded the cheesecake as he would my shoes!  The only cat who paid any attention to us eating was Scruffy, recently passed, who would come begging, triggering other cats to do the same.  This holiday, no one came around for handouts, almost sad to say...

 

We've had a good year and have much to be thankful for.  We're both healthy and gainfully employed, and have been able to relax and travel as we desire - in particular spending time touring the state with our new Russian family.  Similarly our families back in the Midwest are doing well and hope to catch up with them in a few weeks in our "holiday" trip.  Our great sadness this year has been the loss of our dear Scruffy a couple months ago, Atticus going missing in June, and of Marley's passing about a year ago.  Our cats are our family members and it is always sad to lose a dear one.  And of course, we were blessed with Lucy early in the year, though it has been a trying year dealing with some of her issues.  But for the moment, all is calm on the home front.  And while it was a quiet holiday at home, sometimes those are just the sort of break one needs!