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

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.

Save Our ‘Scope: A Gueymard fundraising update & why telescope mirrors matter

If you didn’t already know, we’re in the process of raising money to repair the Gueymard telescope at the George Observatory in the Save Our ‘Scope campaign. And thanks to you, we’ve raised over $65,000 of our $80,000 goal through donations ranging from $1 to $5,000 — and we’re grateful for every last one of ‘em.

But what’s the big deal? I mean, you can totally just buy a new mirror at Target or something, right? Well, in a word: nope.

Telescopes are amazing pieces of equipment – dauntingly large (the Gueymard weighs 10 tons) and yet incredibly delicate. If the mirror in a telescope warps just a few centimeters, it can vastly distort the images you see. Therefore, it’s extremely important to keep these machines in tip top condition.

Eye see you

Think of telescopes as an extension of your eyes. We can’t see things far away very well. When you look at the sky at night (and it’s dark enough) you see tons of tiny specks of light – some are stars, some are planets, others are galaxies, or even galaxy clusters. The light can travel for thousands (or millions or billions) of light years. The light heads right into your eye, onto your retina, and sends a message to the brain that says, “Hey, that’s neat, a speck of light.”

However, due to the distance involved, we can no longer appreciate the scale or detail of the images. The further away an object is, the smaller the space it takes up on the retina.

Telescopes fix all of this so that a bright, detailed image can reach your eye as it captures more light and then focuses and magnifies it.

Light-bending lenses

Lenses bend light waves, either causing them to converge (focusing light) or diverge (spreading out light). Glass lenses were used in the creation of the first telescopes, called refracting telescopes.

In this model, light passes through the objective lens, which collects the light, causing it to converge on the eyepiece where it is then magnified. These images would become distorted, however, as different wavelengths of light bend at different angles and focus at different points.

Mirror, mirror on the wall

So, how do you solve a problem like bent light? In a word: mirrors. With reflecting and compound telescopes, the light doesn’t pass through the objective lens. Instead, it is reflected (via concave mirror) back to a smaller mirror, directing the light to the eyepiece where it is magnified. Ta-da! Beautiful, clear images of faraway objects.

The cool thing here is that the larger your mirror, the more light you capture, giving you higher resolution images with better detail.

The bigger, the better?

If your goal is to capture as much visible light as possible, then yes, bigger is better. But this comes with special problems too. Mirrors can get heavy – very heavy. Think about it: our Gueymard telescope mirror is 36 inches in diameter, and some mirrors can be several hundred inches in diameter. Now that’s a lot of mirror! All of this weight can change the shape of the mirror so that, over time, they sag and no longer properly focus light to another point.

Oh, honey

This issue can be solved with honeycomb mirrors. No, they’re not made by bees. Rather, they’ve been influenced by the structure of a honeycomb. This allows the face of the mirror to be well supported, while reducing the weight of the mirror up to 80 percent.

Now that you’re (sorta) a telescope expert, come see the big stuff at the George Observatory in Brazos Bend State Park! Houston’s really lucky to have this observatory in its backyard, so to speak, since the Gueymard is the largest telescope in the country open to public viewings.

Can you spare a George for the George? We’d greatly appreciate if you pitched in to help save our ‘scope. Your efforts ensure that Houstonians can continue to stargaze through the most incredible telescope they’ll ever get to use for many years to come.

Proof you can shower once a year and still get people excited: The Perseid Meteor Shower hits Saturday!

Showering once a year? It works for the Perseid cloud!

Each year in mid-August, a stream of debris ejected by the Swift-Tuttle comet, called the Perseid cloud, becomes visible to stargazers — as a meteor shower.

These “shooting stars” are actually streaks of light that occur when tiny dust particles in the comet’s debris trail collide with and are vaporized by the Earth’s atmosphere.

Perseus and Perseid MeteorA composite photo of the 2010 Perseid Meteor Shower

The Perseid Meteor Shower has been observed for approximately 2,000 years and was first recorded by stargazers in the Far East.

It’s best to get out of the city and away from light pollution to view the shower, so the George Observatory at Brazos Bend State Park is hosting a viewing party this Saturday, August 11. Meteors may become visible around 10 p.m., but will grow more frequent as dawn approaches.

Says HMNS Astronomer James Wooten: “You will see more meteors in pre-dawn hours than right after dusk. This is because the Earth is running into the stream of meteors rather than the other way around. As a result, the leading edge of the Earth — the side going from night to day — encounters the meteors. Meteors will seem to radiate from a constellation called Perseus (hence the name “Perseids”). In August, Perseus rises in the northeast at dusk and is high in the north at dawn. Thus, meteors will seem to radiate from the northeast.”

The George will stay open until 2 a.m. August 12 to accommodate people who want to view the full spectacle of this stunning celestial shower.

Normal park entrance fees ($7 per person; free for children 12 and younger) apply. Tickets for the Gueymard Telescope are $5 and go on sale at 5 p.m. Tickets to view the night sky through our 11-inch refractor and other large domes will be available for $5 from 9 p.m. until midnight.

As always, personal telescopes are welcome! The shower is also visible to the naked eye. Lawn chairs, bug spray, snacks and blankets are encouraged.