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.

On the Tenth Day of HMNS…Explore the Cosmos at The George Observatory

The first time I went to the George Observatory, I saw Saturn. With my own eyes. Not a picture, not an artist’s rendering – the actual planet. It was…well, let’s just say I left full of a sense of wonder at the universe we live in – and the centuries of scientific achievements that have made that experience possible.

The Gueymard Telescope at the George Observatory is one of the largest in the country that is available for public use – and once you start looking through it, you won’t want to tear your eyes away. Saturday nights throughout the year, local astronomers and museum staff gather at the Observatory, and you can view through the Museum’s telescopes or the dozens that people bring with them. Some people get pretty high tech with it (check out this digiscoped picture) and it’s always a lot of fun.

In the video below, Barbara Wilson, the George Observatory astronomer, discusses what you can see at the Observatory – and talks about the most commonly asked questions, like “Have you ever seen a UFO?” Check out Barbara’s answer in the video below and visit the Observatory this holiday season to get all your cosmic questions answered.

The George Observatory is just one of the fun and fascinating options for families at the Houston Museum of Natural Science. In a take-off of everyone’s favorite holiday classic, The 12 Days of Christmas, we’ve got 12 ideas for fabulous family fun this holiday and we’ll be sharing the possibilities here every day until Christmas Eve. Best of all, most are activities that last past the holiday season – some, year round. You can also check them all out now at the spiffy new 12 Days of HMNS web site.

Check out the first nine days of HMNS:
On the first day of HMNS, explore The Birth of Christianity.
On the second day of HMNS, shop for Sci-tastic gifts.
On the third day of HMNS, meet Prancer the reindeer.
On the fourth day of HMNS, discover the making of The Star of Bethlehem.
On the fifth day, move it, move it with Madagascar 2 in the Wortham IMAX Theatre.
On the sixth day, hunt dinosaurs with Dr. Bob Bakker.
On the seventh day, look inside the human body in BODY WORLDS 2.
On the eighth day, meet the HMNS Entomologists.
On the ninth day, peer into the Gem Vault.

Science Doesn’t Sleep (8.28.08)

Box Turtle Closeup
Creative Commons License photo credit: audreyjm529

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

Paleontologists have found the fossil of a 75-million year old pregnant turtle – something that has never before been found.

We’re lucky to have the Gueymard telescope – one of the largest in the country for public viewing – right in our backyard. But looking into the heavens wasn’t always so easy. Check out this list of 20 things you didn’t know about telescopes.

Are we giving robots too much power? The Onion weighs in.

Now we play the guessing game: what will happen with Hurricane Gustav?

Photos: a new statue of the Emperor Marcus Aurelius has just been uncovered in Turkey.