About Peggy

Peggy is the Director of the George Observatory.

A Celebration and a Restoration: Ringing in 25 years at the George

This Friday we’re kicking off our celebrations in honor of the George Observatory’s 25th anniversary with a members event at the George! Leading up to this anniversary, we launched our S.O.S (Save Our ‘Scope) fundraising campaign to restore the mirror, and, thanks to your generous support, we reached our goal of $80,000 this past spring.

Optical Mechanics, Inc. has been working on our 36” mirror for several months now and in that time has made great progress as well as some surprising findings. The mirror is now 98% finished — but it’s the work for that final 2% that’s proving to be the most critical, taking the mirror from “good” to truly top notch! 

This 2% involves resolving issues with the mirror that are a direct result of the original grind on the mirror.

SOS

The technology used to grind the mirror originally, while cutting edge for the time, left the mirror susceptible to deterioration from imperfections. These imperfections, microscopic bubbles and fissures, allowed for tiny places where “gunk” could get in and stick. Once that formed, there was no way to get a coating to stick to the surface. We ran into this issue in 1994, when we re-coated the mirror, and in this case, we were eventually able to overcome the imperfections. However, this time around, it was absolutely time to regrind the surface and apply a new coating. 

If the ‘scope had been put in the desert or on top of a mountain with a very low amount of humidity, these imperfections may have never compromised the scope. However, both Louisiana and Houston are very high humidity locations. HMNS has owned the telescope and dome for 25 years now, however the mirror itself is 50 years, with LSU having owned the ‘scope for the first 25 years of its life. It has been a good scope for a very long time, for many people. We have always felt strong in our conviction that the ‘scope, like all of HMNS, should be available to everyone in the greater Houston area and Texas. We are close to people. 

The new technology being used to grind our mirror will give us a far superior mirror than it has ever been. We are so excited to get it home and to see the difference! 

That being said, the restoration process is behind where we had anticipated, but we’ve decided that this time is more than worth it to get the high quality we know we will receive if we do not rush this project.  

The mirror will be ready and delivered home as soon as possible this fall and we’ll update you when we know it’s on its way!

The process to grind the mirror is fascinating and time consuming. They grind a while, take the 500 lb. mirror off to check it and then grind the curved surface again and again. Ours is a hyperbola, which makes it even a bit more complicated than other types of telescope mirrors.

Here are some photos of how they carry the mirror and grind it:

George Observatory Mirror Grind 1

Here is how they transport the 500 lb. mirror. Notice the cleaned surface before they began grinding.

George Observatory Mirror Grind 2

This is the first test of the mirror when they received it in February. The lines are supposed to be straight which tells us that the original grind 50 years ago never quite got finished or perfected. It was a good telescope, but not nearly up to the full potential.

George Observatory Mirror Grind 3

First coarse grind. They grind for a period of time and then take it off, look at the surface with the lights and then grind more.

George Observatory Mirror Grind 4

Then they have a fine grinding after the coarse grind. It takes time, patience and almost an artistic ability to get it right.

George Observatory Mirror Grind 5

Latest Ronchi Focault test showing much straighter lines. We expect a slight curve around the center opening. The final figuring will make it even more perfect.

 

We will keep you posted and will let you know as soon as the mirror arrives home. Check HMNS.org and the George Observatory Facebook page for updates. 

 

 

We’ll weather the weather: George Observatory’s dome gets a makeover

Editor’s note: This post is part three of our three-part series on how you helped us save our telescope at the George Observatory. Read part one here, and part two here.

In our Save Our ‘Scope (S.O.S.) campaign, much of our focus was on replacing the mirror in the telescope. This was the first and most obvious thing we realized we needed to fix. However, just as important as the telescope and the mirror (which allows us to see the wonders of the universe) is the dome which protects the telescope and the hydraulic lift floor that allows us to take multiple visitors to look through the ‘scope. 

We have an amazing elevator-type floor that allows us to take many people up to the telescope at the same time. The telescope complex weighs 10 tons, so it will not move anywhere. The floor allows us to let short children and people in wheelchairs still look through the massive telescopes. Historically, most large telescopes have a single chair which lifts the astronomer up to the eyepiece, as you can see in the image of Percival Lowell below.

As computers and imaging have evolved, now most observatories attach a camera to the eyepiece holder and then run a cable to the building downstairs so the astronomer can use a computer to “look” in the telescope. This is pretty convenient (air conditioning and snack foods, anyone?), but it doesn’t allow someone the very personal experience of looking at something amazing in space with their own eye. The George Observatory does have cameras that scientists use when we are not open to the public. We will always use an eyepiece for the public observing.

The next big item to address was the dome itself. Steel in the Houston climate gets much abuse. Most large observatories are placed in deserts or on top of mountains in very low humidity conditions. However, this is not necessarily where many people are located, so we are committed to regular maintenance to keep the dome in good condition. 

Here are the before shots of the dome:

Scope Blog 3 7It wasn’t easy to fix, and we needed to accomplish this before the summer heat set in.

Scope Blog 3 8 Scope Blog 3 6Here is the after shot. The dome is ready to protect the newly refurbished mirror as soon as it comes home! 

Scope Blog 3 9 Scope Blog 3 10

The great balancing act: Stabilizing telescopes at the George Observatory

Editor’s note: This post is part two of our three-part series on how you helped us Save Our ‘Scope at the George Observatory. Read part one here.

Many have asked us how we are still using the large research dome at the George Observatory while the 36-inch mirror is in Iowa getting fixed. The simple answer is that we are continuing to use the 11-inch refractor, which is mounted on the side of the 36-inch telescope. The refractor has near-perfect lenses and is an incredibly high quality instrument in and of itself. The 36-inch mirror is best used for deep space objects, and the 11-inch refractor is best used for closer objects like we find in our solar system. Together, they work in tandem to make a remarkable team to view near and far.

The entire telescope grouping and mount weight approximately 10 tons. The 36-inch mirror weighed almost 500 lbs with the mirror and the center hub that holds it in place.  Because everything is so perfectly balanced, the motor to run the telescopes is approximately the size of a sewing machine motor. This delicate balance is also what keeps the telescope working properly. When we removed the more than 500 lbs. for the primary and secondary mirrors, the entire system was totally out of balance.

We were advised that glass is the same density as cement by our mirror expert.  With this piece of information and the help of Tracy Knauss, Paul Halford and Chris Randall, a plan was devised to make an exact replacement of the glass mirror out of cement. Paul located the materials and then Chris took over the project. He had scales and tools at his home and handily went about making the cement mirror.

First, Chris started with some rebar and a 36-inch sonotube.  

SOS Cement mirrorThen Brazos Bend State Park provided a fork lift to get it out of the truck.

SOS Cement mirror 2

SOS Cement mirror 4Then we had to get the 500-pound blank inside the building and placed underneath the dome so that it could be lifted three stories up into the dome and then installed.

SOS Cement mirror 6Here is the cement mirror blank installed in the real mirror cell.

SOS Cement mirror 9Finally, Tracy and Chris installed the cement blank into the back of the telescope casing where the real mirror will eventually be. By replacing the weight almost exactly, only a very few adjustments had to be made so that it was back in balance and able to support the 11-inch refractor again. 

With Jupiter, Mars and Saturn so prominent right now, this is the best ‘scope for viewing until the 36-inch returns to the George Observatory.

Save the Date: The George Observatory’s 25th Anniversary Celebrations
October 10, 2014: Members and donors event 
October 11 & 12, 2014:  Anniversary weekend. The Observatory will be open  from dusk until 11 p.m. Come look through the newly refurbished 36-inch Gueymard telescope that you helped save!

You saved our ‘scope at the George Observatory! And this is how it happened.

CliffsNotes: Thanks to all of you, we have done exactly what S.O.S. intended, and we saved our ‘scope!

HMNS is proud to own the largest telescope in the country that is open to the public on a regular basis, the Gueymard Research Telescope. Many of you have come and enjoyed the night skies and looked through this amazing telescope at the George Observatory. But it needed some well-deserved TLC this past winter.

SOSYou saved it!

The donations to repair the Gueymard telescope ranged from pennies to $10,000, and came from families, individuals, children, companies and foundations!

Special thanks go to Dr. Reggie DuFour, who launched the campaign with a generous $10,000 donation. We are also extremely grateful to major donations from The George Foundation and The Henderson-Wessendorff Foundation. We were also given a generous donation from elementary students at Shady Oak Christian School, who sent us over the top with their $1,800 donation, which was collected from their annual fun run.

Why is the Gueymard telescope so important to us — and to you?

On a clear night, it is incredible to be able to see with your own eyes the many wonders of the universe. There are other, larger telescopes, but they are far away and they are only available to scientists who apply for time and get their projects approved. These large ‘scopes use cameras which are then fed to an indoor area where scientists “look” with their computers. Here at the George Observatory, we think there is something very personal and magical about using your own eyes to look at Saturn or Jupiter or a galaxy far, far away.

The 36-inch Gueymard mirror and dome were purchased from LSU in advance of the 1989 opening of the George Observatory. LSU had owned and operated the ‘scope for 25 years in highly humid conditions, very similar to the ones in Brazos Bend State Park. Brazos Bend is a swamp and grassland, but it is also located conveniently about an hour away from light-polluted cities in and around Houston.

The unique relationship with Brazos Bend guarantees us a safe, dark place to view the skies. Most telescopes are put on top of mountains or out in dry deserts where the weather conditions allow for more nights of clear skies. When Halley’s Comet returned in 1986, thousands of visitors lined up at the park wanting to see the comet. We knew then, if not before (and certainly now), that there is a high interest level in everything astronomical in Houston.

We believed that because the mirror had already lived in a swamp for 25 years, it should continue to do well in similar conditions. This was true for a long time. However, several years ago we noticed that we really couldn’t see as well with the large scope. The mirror was becoming cloudy. In 2011, it was determined that the mirror surface had lost all reflectivity. After extensive research and phone consultations, the mirror was sent to Marian Schafer at Galco Electronics in Mesquite, TX. Galco, which is well-equipped to put coatings on mirrors, was selected based on its good reputation and, in part, its  Dallas-area location – which allowed our volunteers to transport the mirror, saving shipping costs.

Mirrors are supposed to be shiny. This one was not.

SOS 1Starting in December 2011, Marian stripped, cleaned, baked and held the mirror under a vacuum five times to try to remove contaminants from inside thousands of small microscopic fissures found on the surface and interior of the mirror. In addition, there are numerous other bubbles throughout the glass mirror that can be seen with the naked eye. Galco used a sub layer of chrome as a binder and then put a final coating of aluminum. When this coating failed, titanium was applied as the binder in order to block leeching contamination.

It was understood that if the titanium was put on, the only way to remove it would be to regrind the mirror. The titanium coating failed, and did not bond to the mirror surface. This first attempt helped us to determine exactly what needed to happen next with the mirror.

SOS 3Time to hit the grind.

The next step to fix the telescope was to bring in an independent expert on a Ritchey–Chrétien designed telescope like ours. James Mulhernin, from Optical Mechanics Inc. (OMI) was flown here from Iowa. Mulhernin determined the composition of the glass as excellent quality Pyrex, and also determined that the microscopic fissures were artifacts from when the mirror was originally made almost 50 years ago. Over time, pollution and microscopic “gunk” in the fissures prevented a coating from sticking to the mirror.

Mulhernin’s newer technology will allow us to re-grind the mirror and prevent any of these old issues from coming up again in the future. This is indeed great news for us here at the George Observatory.

SOS 4The mirror was shipped to OMI and is currently being serviced. Reports are all very positive.

While the mirror is gone, we can still use the amazing 11-inch refractor with near-perfect lenses mounted on the side of the big telescope. But that’s another story as to how we removed a 458-pound mirror and can still remain open on Saturday nights!

Stay tuned for more updates on the repair progress, and start looking forward to the 25th Anniversary celebrations in October here at the George Observatory.