Blast From The Past!

It was a year ago that amateur astronomers were marveling over comet Holmes. Discovered back in the 1800s, it was a minor comet that normally would only be detectable with a camera and a good sized telescope. Then on the 23rd of October, 2007 it brightened by OVER A FACTOR OF A MILLION! This is just unheard of, particularly at it's distance from the sun, between Mars and Jupiter far from the sun. It was catapulted to easy naked eye brightness, even with a bright moon in the sky. It was phenomenal! At first appearing nearly star like, it slowly expanded in the vacuum of space.


I first imaged it from my front yard in Tucson. I set up the 14" Celestron and was taking 10 second (!) exposures to keep from overexposing it. Shown here is a stack of 6 exposures showing the mostly spherical shell of the coma, the lack of a tail, and a fuzzy little pseudo-nucleus (the actual nucleus is only a mile or two diameter and not resolvable).



This next exposure is almost 6 weeks later with the same optics, so is shown at the exact same scale. The exposures are a little longer, so more stars show, in fact, a little galaxy shows through the coma to the upper right of the nucleus. It has expanded dramatically in that time, but was still easily visible to the naked eye, and stayed so for several more months before fading in the spring as it continued to expand into nothingness.

About 3 months later on March 8th (2008) the faded comet passed the gaseous California Nebula, and I was able to image it with a 200mm lens. Now a couple degrees across, it was still visible in binoculars and the fuzzy bit of nucleus was still visible.


I read a report recently that theorizes the collapse of an ice cave, releasing millions of tons of ice and dust into the solar system, explaining the sudden brightness. It has something of a history of this - it was in outburst when Edwin Holmes discovered it in 1892. So it has happened in the past and likely will again!

New treads...

After the flat tire on my Jeep last week (or maybe it was the week before?), I have been lulled into getting new tires. That was one of the tasks for yesterday. Not that I didn't believe that I needed them, I just didn't like having to get them! The guy that does Dean's tires is still in a bit of disbelief that I made the tires last as long as I did. They still had tread, mind you, and I'm guessing I could have squeaked a few thousand more miles out of them. As it was, they were the original tires that were put on the Jeep when it was 'born' - back in 2001. Actually, the tires had a date of 2000 on them - so they were 8 years old. Additionally, I managed to get 76,480 miles out of them I'm proud to say! They questioned Dean about the tires when he took the flat one in to be fixed (prompting him to call me at home and ask if they were the original tires). When we took the car into the tire place yesterday they questioned me about them being the originals (in a voice of disbelief). When we picked the Jeep up, a few hours later, again the guy questioned me.."...so these are the original tires?????" He couldn't promise me that the new ones would last me another 75,000 miles - but Dean promised that when I have to replace the tires again I can get a new Jeep (my previous answer to car maintenance....needs big stuff done? Time for a new one!). Dean, are you reading this??? You promised!! As is probably guessed, I didn't bring my camera out to Tucson with me. With Dean having great cameras, I didn't see the need. I'll have to ask him to take pictures of my new "Light Truck Uniroyals" for the blog!

Work At The Mirror Laboratory

Many of my friends and relatives know that we make telescope mirrors at the lab, but do not know any of the details. It is precision work, but nothing magical about it, so I'm hoping to post some of the activities we go through to make the largest telescope mirrors in the world.

For the past 2 weeks, we've been in the unusual position where there is no work being done on the GMT (Giant Magellan Telescope - 8.4 meters segment diameter) mirror itself, but rather on getting the polishing machine ready, as well as doing some work on the support system that holds the mirror properly in the polishing cell while we are grinding and polishing. Each of those tasks have manpower assigned to them, so the fabrication crew had time to closely examine the mirror for defects of any kind that need attention before proceeding with work. So late last week Kevin and I were on our bellies inspecting the mirror surface with flashlights and magnifiers to seek out flaws. Generally they were of 3 kinds - bubbles (which generally just needed some beveling so as to not become an issue), fractures (small ones can be safely ignored), and seeds (impurities embedded in the glass - when exposed on the surface they play havoc with polishing and need to be ground out). So the last 2 days, we've been bubble beveling (say that fast 3 times!) and using a dremel-mounted diamond tool to remove seeds.

Shown are the tools of the trade, including a hand loupe for a close up view of the defect, a head mounted magnifier used when grinding, water to cool the diamond tool, dremel with 2mm diameter diamond ball, a cylindrical stone with cone tip to smooth out the diamond finish, and of course, a flashlight to get some light on the subject.

Here is a typical seed - I'm not sure if they are flaked bits of refractory from casting or what, but many have associated fractures, since they are high-stress areas. Generally they need removal, or at least get them below the surface so they will not be exposed by further processing. We've got about .25mm to remove yet, so my goal is to grind them to a depth greater than that.

After a few minutes with the tool, the bulk of the seed is gone and the remaining fractures and seed is down the side of the beveled divot safely away from the surface. Once treated, they get the DK seal of approval (Dean Ketelsen) and a note on a logsheet for future reference. More from the Lab when something interesting comes along!

Four days off...

Yippeee! I have four days off (well, actually, only two more off...I've been off two already)! See the previous post as to what we did on my first night off. Dean was pretty kind when he said it was cold out. Man-o-manochevitz it was freezing! Even with layers and blankets on, I was shivering! It's always amazing how it can be so cold up in the mountains and then by the time we get back to Tucson we're taking off the layers because it's warmer in town - lower altitude. It was a good night of observing, however, and Dean took some really nice pictures! The first time I came to visit Dean in Tucson we went observing on Kitt Peak and he took a picture of us observing together. I think I should add the one from Empire Ranch to a frame with the original one!

Last week I picked up the 'new' (antique) table for the dining room. We only had two chairs that would work with that table, so that started another 'quest' for us. Since this past Friday I have hit most of the thrift shops on the west side of Tucson, in search of chairs! That quest ended yesterday with the finding of chair numbers 5 and 6. Oddly, all of the chairs we've gotten at the thrift shops are very similar. It just seems like someone took chairs around to the shops and dropped one at each shop! It would have saved me some gas if they had taken them all to the same place. The next part of this project is getting them to all be about the same color - preferably the color of the table. One of the four chairs is pretty close, it's the other three that need to be changed. That means a trip to the hardware store to see what kind of products I can find. That's my goal for this morning!

Last evening we went to the photo group from the astronomy club. The photo group is a sub-group of the TAAA (Tucson Amateur Astronomers Association) that Dean spearheaded quite some time ago. It's for people who are interested in astro-photography. They share pictures, of course, but also great tips on what equipment to use and how to use it to it's fullest potential. They meet at a local Chinese restaurant once a month. First there's dinner and socializing, then the pictures and instructional part of the evening. Many of the group are people that I know from the regular group - and are friends. I did get to meet some new people last night, however, and also saw a friend I hadn't seen for a couple of years. Dean shared the pictures that he took on Sunday night - which everyone enjoyed. It was a nice evening!

This morning I have completed my work schedule for most of February. I have always had 'block hours' (the same thing every two weeks) at my previous job. This is my first foray into "self scheduling" and I was concerned. It's much easier than I thought it would be! UMC has an incredible staffing software program which can be accessed from my computer here at home. That allows everyone to have equal chance to get their schedule in and not be left with the 'bad shifts' only. Even after this first time of doing my schedule, I feel like I really have the 'hang of it'! Yea!

Dark Sky Viewing

With the waxing moon about to brighten the early evening sky, Melinda and I headed out of town last night to catch the planetary alignment and do some more observing. Instead of heading west towards Kitt Peak like I usually do, we went southeast to what used to be called Empire Ranch, now called Las Cienegas. About 8 miles north of Sonoita, it is some pretty, high (about 5,000 feet elevation) grassland. Tucson leaves quite the light dome to the northwest, but I wanted a dark eastern sky, so it was a good choice.

We got out there about sunset and boy, did it cool down quickly! I was running 2 cameras, one on a small telescope and the other on a tracking mount, so was a blur setting up equipment. Melinda set up her 5" Celestron for visual observing. As it was about to get dark, I saw how photogenic the alignment was in the west so tried combining a few exposures with self-portraits, using the on-camera flash to light us up. This image is my favorite. Moon, Venus and Jupiter in order from brightest to faintest...

My observing program was to get a fairly deep exposure on the constellation Taurus. On one of the astro-photo groups, T. Wade Earle posted a CCD shot (like a digital camera, but with higher sensitivity and a dedicated cooling system) that is shown here. The entire area east of the Pleiades and the California Nebula (named for it's shape) is full of dark nebulae and molecular clouds. My effort (also shown here) is not as deep, but is starting to show the combination of dark and diffuse nebulosity. I'm still exposing far less than Wade was, so may add more to the exposure - my exposure was 35 minutes with the Canon 20Da and 50mm lens at F/2.8.

While this was going on, I was also shooting a little Meade 80mm F/6 lens on a couple objects. My first target was the dual object NGC 253 and 288. The former is a galaxy only 10 million light years away (close for galaxies!) and the cluster is only 28,000 light years away, part of our own Milky Way galaxy. This image is added from 10 exposures of 6 minutes each with the Canon XSi, so totals an hour of exposure. There is a little gradient at the bottom (sort of a reddish glow) that needs correction, but wanted to get it on the blog!

The last shot with the little Meade scope is a quick series on the Pleiades - 5 exposures of 2.5 minutes each. The cluster is young (only 100 million years or so), and is close by (and easily visible to the naked eye as a diffuse cloud in the east this time of year) at about 440 light years. It was once thought that the diffuse nebulosity in the photo was leftover gas from formation of the cluster, but is now thought the motion of the cluster happens to bring it through the gas cloud.

It was a fun night, but cold, so we didn't mind closing up early so that we could be in bed by midnight - it was a "school" night, after all!

Flandrau Planet Viewing

Tonight I joined other amateur astronomers in setting up telescopes outside the Flandrau Science Center for the Venus-Jupiter conjunction. Setting up on the mall in front of Flandrau is always fun because the high volume of foot traffic near the center of campus always draws an interested crowd. Tonight especially there seemed to be lots of kids, and not all were there for the featured speaker - Patrick Woida, scientist from the Phoenix Mars mission was to speak at the Center after some planet viewing. There were easily over a dozen scopes there, including Tucson Amateur Astronomy stalwart John Kalas.


I set up the 7" apochromatic refractor that my friend Roger built a few years back - it is easier to setup than the 14" and gives fine, color-free images. It also has an unusual optical layout (uses 2 mirrors to fold the beam) so it makes people ask about the unusual eyepiece position. Setup before sunset, I had a crowd early on, first looking at easy-to-find Venus, then the Moon before it set, then my favorite, Jupiter. Channel 13 was there doing a live broadcast, but they didn't get down to my edge of the telescope line... We had good crowds, though a brisk breeze made it feel a lot colder than it actually was. Seeing was pretty bad too, though Jupiter's moons, cloudbands, and the partially illuminated disk of Venus was easy for all to see.


Even Melinda made it down for a short time before her shift started at UMC tonight. Here she is shown with Chuck and his ultra portable Pronto. Finally, after a few hours of observing the planets down into the murk, I was able to get people away from the eyepiece long enough to shut down and put away equipment. Chuck, his friend Chunmei and I went out for a beer and sandwich at Barrio Brewery before getting home about 9:30. A nice early end to a pleasant evening of observing.

Be sure to watch the conjunction Sunday and Monday night as the moon moves past Venus and Jupiter!

Best Buy Incident

Ever have a store do the right thing, but leave you feeling guilty? With Electronic City filing for bankruptcy, the local choices for electronics gear is getting thinner. So much so that I braved "Black Friday" crowds at Best Buy yesterday to get a spare battery for my Canon XSi. I knew they sold the camera and unlike department stores, would likely sell batteries and a few accessories too.

Though crowded, there was a young staff person there who quickly ran off to fetch a battery for me (an aisle away from the cameras). I thanked her and asked her how much it was and she responded thirty-something dollars (all I remembered was the "3" in front, which was fine). Then we got in the long line for checkout, which moved quite rapidly, actually. However, after scanning the item 4 times, it evidently was not a recognizable inventory item, and we waited while a manager ran off for a new barcode. When she returned, the register said $54 for the battery. I mentioned to the manager that the staff person said it was less than that so we went on a hunt for that nice young lady who again, repeated for the manager that she had said $39. She was rewarded with a glare from her boss and I was only charged the $39, but hated to think I got someone in trouble. I offered to pay the correct price but was declined.

While I admire the store for only charging me the price I was quoted, I still feel bad that the young lady got "dressed down" for quoting an incorrect price on an obscure inventory item. Since the store is only a mile or so from the house, I'll definitely be spending more there...