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.

From white dwarves to dark matter: 75 years of discovery at McDonald Observatory

Editor’s Note: Today’s post comes to you from Rebecca Johnson, Editor of the StarDate Magazine at the McDonald Observatory.

A year-long celebration is underway to celebrate the 75th anniversary of the University of Texas at Austin’s McDonald Observatory, with the first event of 2014 being held at HMNS on Tues., Jan. 14 with a public lecture by Dr. Jon Winget.

McDonald Observatory 1

Photo credit: Sandia National Laboratories

Dubbed “impossible stars,” white dwarfs are the simplest stars with the simplest surface chemical compositions known — yet they are very mysterious. The McDonald Observatory leads in investigating white dwarfs along several avenues: telescope observations, theory, and most recently, the making of “star stuff,” using the most powerful X-ray source on Earth at Sandia National Laboratory.

Dr. Don Winget, one of the world’s leading experts on white dwarfs, will give a Distinguished Lecture at HMNS to examine the how studies of these stars can shed light on everything from the age of the universe to the understanding of dark matter and dark energy.

White dwarves are often difficult to locate due to the larger, brighter stars they are paired with

Located near Fort Davis, Texas, under the darkest night skies of any professional observatory in the continental United States, McDonald Observatory  hosts multiple telescopes undertaking a wide range of astronomical research. McDonald is home to the consortium-run Hobby-Eberly Telescope (HET), one of the world’s largest, which is being upgraded to begin the HET Dark Energy Experiment. An internationally known leader in astronomy education and outreach, McDonald Observatory is also pioneering the next generation of astronomical research as a founding partner of the Giant Magellan Telescope. The McDonald Observatory was dedicated May 5, 1939, and has supported some of the most important astronomical discoveries of recent decades about everything from extrasolar planets to exotic stars and black holes.

The Observatory plans a full year of activities around the state to celebrate. Events will run through August 2014, including a lecture series featuring McDonald Observatory astronomers in multiple cities and an Open House at the Observatory.

The celebration continues at the observatory’s website. Visitors to the anniversary pages can peruse a timeline of observatory history, watch several historical videos, and share their memories and photos of McDonald on an interactive blog called “Share Your Story.”

McDonald Observatory 2
(And while we’re at it, don’t forget about our own George Observatory‘s anniversary this year as well — 25 years of showcasing the night sky to the Greater Houston area!)

HMNS Distinguished Lecture
Date: Tues., Jan. 14, 6:30 p.m.
Topic: “Small Stars in a Large Context: All Things White Dwarf”
Speaker: Don Winget, Ph.D.
Where: HMNS Wortham Giant Screen Theater
How: Click here for advance tickets

Sponsored by the University of Texas at Austin’s McDonald Observatory in celebration of their 75th anniversary, with a pre-lecture reception at 5 p.m.


A different kind of New Year’s “resolution”: So you want to be an amateur astronomer

So you want to be an amateur astronomer? Well there’s never been a better time to explore the heavens — from right here on Earth.

Enter the telescope.

Telescopes have been around for quite some time. Invented in 1608 in the Netherlands, the first major discoveries came from Galileo Galilei — using an instrument he built and refined himself. So even from the beginning, space study and exploration had deep roots in the uninitiated who wanted to learn more about the brilliance of the night sky.

Now lucky for you, telescopes have become relatively easy to acquire, so there’s no need to build your own (unless, of course, that’s your jam — in which case, you may want to check out the resources here, here and here). They’re available at many “big box stores,” and, of course, online.

And I’d be willing to bet that many of you received one as gift over the holidays.

So now you have a telescope. It’s been sitting in the box for two weeks. What’s next?

It just so happens that we’re offering telescope classes at the George Observatory on Sat., Jan. 11! Here, an expert can help you set up your scope, polar align it, and make sure you’re ready to start stargazing like never before (click here for more information about our telescope classes).

The other key to making your telescoping adventures a success is knowing what to look for. Once again, you’re in luck. Thanks to the glories of the Internet, you can find a multitude of resources to help.

Here are some of my favorites:

Star Chart
Available for Apple and Android devices, this incredibly user-friendly app allows you to find and learn about constellations/planets/galaxies right on your smart phone — before taking aim with your telescope.

Complete with a 2014 Sky Guide, weekly podcasts, friendly tutorials and more, this site (and magazine) can definitely help you learn your way around the night sky.


Why not make your hobby a social outlet as well? Connect with other amateur astronomers in your area for tips, social gatherings, interesting news and photos. And for those ambitious enough to want to explore astrophotography, there are resources for you here as well.


BEYONDbones, the HMNS Blog
One awesome part about the night sky is that it’s always changing, from season to season. Keep up with what to look for in the sky with monthly blog posts from James Wooten, our Planetarium Astronomer.

Last but not least, you can often get updates and interesting information on NPR, The Huffington Post, and Wiki How.

Now you’ve got all the tools to start exploring the cosmos! Happy stargazing! And don’t forget to check out the resources at your fingertips at the George Observatory.

Comet ISON Sprouts a Double Tail

Today’s guest post is written by John Moffitt, Astrophysicist & HMNS Volunteer.

Amateur astronomers are getting a better look at Comet ISON as it dives toward the sun for a Nov. 28th close encounter with solar fire. As the heat rises, the comet brightens, revealing new details every day. This photo, taken Nov. 10th by Michael Jäger of Jauerling Austria, shows a beautiful double tail. One tail is the ion tail. It is a thin streamer of ionized gas pushed away from the comet by solar wind. The filamentary ion tail points almost directly away from the sun.

Comet Ison gets a double tail - 111013 - crop

The other tail is the dust tail. Like Hansel and Gretel leaving bread crumbs to mark their way through the forest, ISON is leaving a trail of comet dust as it moves through the solar system. Compared to the lightweight molecules in the ion tail, grains of comet dust are heavier and harder for solar wind to push around. The dust tends to stay where it is dropped. The dust tail, therefore, traces the comet’s orbit and does not point directly away from the sun as the ion tail does.

Comet ISON is currently moving through the constellation Virgo low in the eastern sky before dawn. Shining like an 8th magnitude star, it is still too dim for naked eye viewing, but an increasingly easy target for backyard optics. Amateur astronomers, if you have a GOTO telescope, enter these coordinates.

Four comets visible in the pre-dawn eastern sky. Look with binoculars before the sun comes up.

4 comets skymap - 111213

Comet ISON Briefings at HMNS

November 29 – December 1

To find out whether Comet ISON survives its close encounter with the Sun and how to see it in December’s morning sky, come to the Burke Baker Planetarium Friday through Sunday of Thanksgiving weekend. An ISON update will precede each Planetarium show!
“Tracking Comet ISON and Other Possible IMPACTS”
Thursday, December 5, 6 p.m.
Tickets $18, Members $12
Comets and asteroids that roam the inner solar system and are a possible threat to Earth. Comet ISON will be grazing the Sun on November 28, and if it survives, it may come within our view. Dr. Sumners will give an update on Comet ISON and other incoming objects. Includes viewing of the show Impact!

Click here for tickets and more information on the Comet ISON briefings.