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.

Sept. Flickr Photo of the Month: Museum Reflected

Our science museum is lucky enough to have talented and enthusiastic people who visit us every day – wandering our halls, grounds and satellite facilities, capturing images of the wonders on display here that rival the beauty of the subjects themselves. Thankfully, many share their photos with us and everyone else in our HMNS Flickr group – and we’re posting our favorites here, once a month. (You can check out the first two picks: “Leaf’s Eye View,” by AlphaTangoBravo and “Rice Paper Butterfly” by emmiegrn.)

There are so many stunning images in the pool, it’s always tough to choose. This month’s pick, “Museum Reflected” by bryan.dawson is a striking portrayal of something most people don’t examine too closely – the globe on the tip of our sundial. Here’s what bryan.dawson had to say about his shot – which includes an interesting perspective on composition:

“It was only recently that I even realized that you could take photos in most of the museum. It wasn’t until one of my Flickr groups, Assignment Houston, had an assignment at the museum that I even considered taking my camera along. I missed the big group gathering (you might have seen it mentioned on the HMNS blog as well), so I went on my own later.

I think I drove my fiancee mad since I stopped every few feet to take a photo. This particular photo was one of the very last ones I took that day. My fiancee wanted to look around the gift shop, so I went outside to snap a few. The clouds were blocking the sun just enough to send out some tendrils of light. It was a beautiful sight, but I knew it would look better if there was something in the foreground. That’s when I noticed that the ball on top of the sundial was mirrored and you could see the museum reflected back in it.

That was it … I lined it up, and what you see is the result. I tried lots of different post-processing on it before deciding upon a monotone coloring. I like to think it lets you focus on the composition instead of being distracted by the colors.”

Many thanks to bryan.dawson for allowing us to share his beautiful photograph. We hope this and all the other amazing photography in our group on Flickr will inspire you to bring a camera along next time you’re here – and show us what you see.

Science Doesn’t Sleep (7.22.08)

batfog
Creative Commons License photo credit: igKnition.

So here’s what went down after you logged off.

More than 100 species of bat have been found in only 5 acres of Ecuadorian jungle.

Getting your teeth cleaned gives you a panic attack? No worries – the pick-and-mirror routine might soon be replaced by light.

The latest unintended consequence of global warming: kidney stones. That’s right – and you can read more about our thinner, hotter, smoggier future in Popular Science.

Before CERN’s Large Hadron Collider can start colliding, it’s got to get really, really cold.

When you suddenly fall into the category of “might cure cancer,” sometimes you really deserve a new name. Researchers are currently looking at pond scum as a possible source of new cancer therapies.

The presence of a mirror makes people less likely to cheat. Scientists are using mirrors in a surprising number of ways to test brain function with often surprising results.

The Houston Zoo has a new resident: Vincent, a rare St. Vincent Amazon Parrot.  

If you’ve been following Chris Linder‘s posts from the Greenland Ice Sheet, check out KUHF’s story on the WHOI science team’s live-from-Greenland call to our summer campers yesterday.