June 2006 Newsletter

Stockton Astronomical Society

Valley Skies

Valley Skies - June 2006 Issue

Editor's Corner...

Trickle-down Technologies

The announcement (on page 7 of the newsletter) of the Chabot Science Award to Dr. Claire Max for her work in adaptive optics set me wondering...How long do you suppose it will take for adaptive optics technology to filter down to the affordability level of the amateur astronomer?

Don't be too quick to dismiss that idea. Look at the technologies that have been adapted to amateur telescopes in recent years. Computerized auto-guiding with GPS, sophisticated digital imaging and Richie-Chretien optics have become routine offerings at prices well within the reach of serious amateurs.

However, my favorite example of mind-blowing technology already well established in consumer electronics is the DLP technology used in the DELL digital projector which the SAS bought last year. Digital Light Processing uses light reflected from up to two million microscopic mirrors on a silicon chip. Each mirror, representing one pixel, can be tilted to ON and OFF positions, controlled by a digital signal. Combined with light fed through a color wheel, the DLP process produces high resolution images in projectors and HDTV.

The micro-mirror chip was developed less than 20 years ago by Texas Instruments. Has DLP technology been tried in adaptive optics instead of deformable mirrors? Is it adaptable? I've no idea...maybe we should ask Dr. Max...but it's interesting to speculate.

We'll explore these technologies more in a future issue.

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Amateur Telescope Making - with Rich Combs

We are pleased to welcome Rich back to the SAS after an eleven year absence. Rich Combs last spoke to the SAS in August of 1995.

An optical engineer at Lawrence Livermore National Laboratory, Rich is also a long-time member and amateur telescope maker with the Tri-Valley Stargazers. He was a charter member of Project ASTRO in the early nineties, and is active with the Forest Service and National Park Service presenting astronomy to the public.

Rich has worked with optical systems and lasers for 25 years at Lawrence Livermore Lab. Bitten by the telescope making bug shortly after college, he has fabricated a number of mirrors and telescopes, and helped over 50 amateur telescope makers grind their own mirrors and make their own scopes.

Rich will present an introduction to the history of ATM'ing, describe the general process for making a mirror, talk about some unusual amateur telescopes, and do his best to infect you with the amateur telescope making bug and aperture fever.

Welcome back, Rich!

...Trevor Atkinson

2006 Shingletown Star Party -- June 21 - 26, 2006

"Good friends, Dark skies"
Come join the fun under great skies!

SSP has a family atmosphere. Amenities are minutes away in Shingletown. Excellent hiking and trout fishing in the area, and Mount Lassen Volcanic National Park is only 17 miles away!

Shingletown is located about 35 miles east of Redding in Northern California on Hwy 44.

For information and to register, go to the SSP Web site: www.shingletownstarparty.org

The Science Directorate at NASA's Marshall Space Flight Center sponsors the Science@NASA web sites. The mission of Science@NASA is to help the public understand how exciting NASA research is and to help NASA scientists fulfill their outreach responsibilities.

Breathing Moonrocks

The Moon has plentiful oxygen for future astronauts. It's lying on the ground.

May 5, 2006: An early, persistent problem noted by Apollo astronauts on the Moon was dust. It got everywhere, including into their lungs. Oddly enough, that may be where future Moon explorers get their next breath of air: The moon's dusty layer of soil is nearly half oxygen.

The trick is extracting it.

Apollo 17 geologist Harrison "Jack" Schmitt scoops up some oxygen-rich moon rocks and soil.

"All you have to do is vaporize the stuff," says Eric Cardiff of NASA's Goddard Space Flight Center. He leads one of several teams developing ways to provide astronauts oxygen they'll need on the Moon and Mars.

Lunar soil is rich in oxides. The most common is silicon dioxide (SiO₂), "like beach sand," says Cardiff. Also plentiful are oxides of calcium (CaO), iron (FeO) and magnesium (MgO). Add up all the O's: 43% of the mass of lunar soil is oxygen.

Cardiff is working on a technique that heats lunar soils until they release oxygen. "It's a simple aspect of chemistry," he explains. "Any material crumbles into atoms if made hot enough." The technique is called vacuum pyrolysis--pyro means "fire", lysis means "to separate."

"A number of factors make pyrolysis more attractive than other techniques," Cardiff explains. "It requires no raw materials to be brought from Earth, and you don't have to prospect for a particular mineral." Simply scoop up what's on the ground and apply the heat.

A lens focuses sunlight onto a vacuum chamber filled with simulated moondust, producing oxygen and "slag."

In a proof of principle, Cardiff and his team used a lens to focus sunlight into a tiny vacuum chamber and heated 10 grams of simulated lunar soil to about 2,500 degrees C. Test samples included ilmenite and Minnesota Lunar Simulant, or MLS-1a. Ilmenite is an iron/titanium ore that Earth and the Moon have in common. MLS-1a is made from billion-year-old basalt found on the north shore of Lake Superior and mixed with glass particles that simulate the composition of the lunar soil. Actual lunar soil is too highly prized for such research now.

In their tests, "as much as 20 percent of the simulated soil was converted to free oxygen," Cardiff estimates.

What's leftover is "slag," a low-oxygen, highly metallic, often glassy material. Cardiff is working with colleagues at NASA's Langley Research Center to figure out how to shape slag into useful products like radiation shielding, bricks, spare parts, or even pavement.

The next step: increase efficiency. "In May, we're going to run tests at lower temperatures, with harder vacuums." In a hard vacuum, he explains, oxygen can be extracted with less power. Cardiff's first test was at 1/1,000 Torr. That is 760,000 times thinner than sea level pressure on Earth (760 Torr). At 1 millionth of a Torr -- another thousand times thinner -- "the temperatures required are significantly reduced."

Slag--a low-oxygen byproduct of Cardiff's device. Slag may prove useful as a raw material for bricks, pavement or radiation shielding.

Cardiff is not alone in this quest. A team led by Mark Berggren of Pioneer Astronautics in Lakewood, CO, is working on a system that harvests oxygen by exposing lunar soil to carbon monoxide. In one demonstration they extracted 15 kg of oxygen from 100 kg of lunar stimulant-an efficiency comparable to Cardiff's pyrolysis technique.

D.L. Grimmett of Pratt & Whitney Rocketdyne in Canoga Park, CA, is working on magma electrolysis. He melts MLS-1 at about 1,400 deg. C, so it is like magma from a volcano, and uses an electric current to free the oxygen.

Finally, NASA and the Florida Space Research Institute, through NASA's Centennial Challenge, are sponsoring MoonROx, the Moon Regolith Oxygen competition. A $250,000 prize goes to the team that can extract 5 kg of breathable oxygen from JSC-1 lunar simulant in just 8 hours.

The competition closes June 1, 2008, but the challenge of living on other planets will last for generations.

Got any hot ideas?

Author: Dave Dooling | Production Editor: Dr. Tony Phillips | Credit: Science@NASA

Not a Moment Wasted

by Dr. Tony Phillips

The Ring Nebula. Check. M13. Check. Next up: The Whirlpool galaxy.

You punch in the coordinates and your telescope takes off, slewing across the sky. You tap your feet and stare at the stars. These Messier marathons would go much faster if the telescope didn't take so long to slew. What a waste of time!

Don't tell that to the x-ray astronomers.

"We're putting our slew time to good use," explains Norbert Schartel, project scientist for the European Space Agency's XMM-Newton x-ray telescope. The telescope, named for Sir Isaac Newton, was launched into Earth orbit in 1999. It's now midway through an 11-year mission to study black holes, neutron stars, active galaxies and other violent denizens of the Universe that show up particularly well at x-ray wavelengths.

For the past four years, whenever XMM-Newton slewed from one object to another, astronomers kept the telescope's cameras running, recording whatever might drift through the field of view. The result is a stunning survey of the heavens covering 15% of the entire sky.

Sifting through the data, ESA astronomers have found entire clusters of galaxies unknown before anyone started paying attention to "slew time." Some already-known galaxies have been caught in the act of flaring-a sign, researchers believe, of a central black hole gobbling matter from nearby stars and interstellar clouds. Here in our own galaxy, the 20,000 year old Vela supernova remnant has been expanding. XMM-Newton has slewed across it many times, tracing its changing contours in exquisite detail.

The image on the left is the Vela Supernova Remnant as imaged in X-rays by ROSAT. On the right are some of the slew images obtained by XMM-Newton in its "spare" time.

The slew technique works because of XMM-Newton's great sensitivity. It has more collecting area than any other x-ray telescope in the history of astronomy. Sources flit through the field of view in only 10 seconds, but that's plenty of time in most cases to gather valuable data.

The work is just beginning. Astronomers plan to continue the slew survey, eventually mapping as much as 80% of the entire sky. No one knows how many new clusters will be found or how many black holes might be caught gobbling their neighbors. One thing's for sure: "There will be new discoveries," says Schartel.

Tap, tap, tap. The next time you're in the backyard with your telescope, and it takes off for the Whirlpool galaxy, don't just stand there. Try to keep up with the moving eyepiece. Look, you never know what might drift by.

See some of the other XMM-Newton images at http://sci.esa.int. For more about XMM-Newton's Education and Public Outreach program, including downloadable classroom materials, go to http://xmm.sonoma.edu.

Kids can learn about black holes and play "Black Hole Rescue" at The Space Place, http://spaceplace.nasa.gov/, under "Games."

This article was provided by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.

DR. CLAIRE MAX TO RECEIVE CHABOT SCIENCE AWARD

OAKLAND, CA (May 3, 2006) - Chabot Space & Science Center is pleased to announce Dr. Claire Max, Professor of Astronomy and Astrophysics at the University of California, Santa Cruz and Astronomer at UC Observatories, as this year's recipient of the Chabot Science Award, to be presented at the Center's Gala on May 20, 2006. The $5,000 award honors excellence in the field of scientific and technological discovery and is in recognition of her work in adaptive optics, a technology that can remove the blurring effects of turbulence in the earth's atmosphere, allowing telescopes on the ground to see as clearly as if they were in space.

Dr. Max has been active in the development of advanced adaptive optics systems for current and future large ground-based telescopes and has observed nearby active galactic nuclei (galaxies with black holes in their cores), the planet Neptune, and Saturn's moon, Titan. Dr. Max graduated from Radcliffe College and earned her doctorate at Princeton University. She is a Fellow of the American Academy of Arts and Sciences and the American Physical Society.

"We are extremely proud to have this opportunity to honor Dr. Max for her outstanding contribution to science," said Dr. Edward Penhoet, chair of the selection committee and a member of Chabot's Board of Directors. "Not only is the use of adaptive optics useful in learning about space objects and understanding the universe, her research also promises to provide new tools for the diagnosis of eye disease, and for improving the correction of vision via laser surgery and contact lenses."

Max is also the Director of the Center for Adaptive Optics at UC Santa Cruz, one of a number of Science and Technology Centers funded by the National Science Foundation. The center is involved in the design of a ground-based 30-meter telescope, to be equipped with adaptive optics (a giant segmented mirror telescope, or GSMT). Once completed, the telescope will be able to make distant-galaxy images that are more than ten times sharper than those of the Hubble Space telescope, detect planets around young stars in the closest "stellar nurseries," and to see more clearly what is happening close to the million-solar-mass black hole in the core of our own Milky Way galaxy.

Stars twinkle at night because their light is distorted by air currents in the atmosphere. Unless a telescope has an adaptive optics system, the images received will be blurred and fuzzy. This same blurring can occur in the living retina. The use of adaptive optics technology can compensate for these aberrations, enabling a new era in astronomy and human eye research and vision correction. The cost of building the land-based Keck Adaptive Optics telescope was about twenty times less than the cost of building the Hubble telescope; yet Keck has a larger light gathering area and a better resolution. Adaptive optics utilizes a high speed computer to actively compensate for the changing distortions that cause blurring of images. Additionally, the system requires precision optics, special sensors and deformable mirrors.