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Journal of the Amateur Astronomers Association of New York March 2010 Volume 58 Number 3, ISSN 0146-7662

EYEPIECE
will save significant weight. According to Arenberg, the design "has to be buildable, with no reinvention of the wheel." The JWST will be a very large space telescope. The larger the light-collecting surface, the fainter the objects it can see. The telescope will fold out. It will have individual mirror segments, each with 7 degrees of freedom of movement and able to be reconfigured in degree of curvature. They'll be made of gold-coated beryllium, which will maintain shape at operational temperatures. The telescope will operate just degrees above absolute zero. It will be "passively cooled," without a main cooling system. Rather, it's designed to radiate heat into space and to shade the telescope side from the Sun. This sunshade is provided by a five-layer shield that will unfold after launch. It will allow the telescope to get cold and to stay cold. The JWST will operate at the Lagrange 2 point, on the side of Earth away from the Sun. Even at this point of stability of gravitation, the telescope will be actively held in orbit, and thus will require some fuel. It also will require fuel for maintaining its orientation to shield itself from the Sun. The fuel requirement will limit its life to some five years. Developers hope that as much as 10 years of operation may be possible since after the design is complete, the telescope's final weight will determine how much fuel can be loaded. The current schedule calls for a 2014 launch. As the JWST speeds toward L2, the sunshade will open and the mirrors will unfold to be a light-collecting source about six times the size of the Hubble's. The JWST will speed Webb continued on page 14

Webb Telescope Will Go Where None Have Gone Before
By Edward J. Fox
The upcoming James Webb Space Telescope (JWST) will be an ultimate science mission, designed to look back to the post-natal early period of the universe-the very early galaxies that formed after the Big Bang-- attendees at a February 8 Hayden lecture heard. The status of the JWST was discussed by Jon Arenberg, deputy systems engineer of Northrop-Grumman, a major JWST contractor. Key to Webb's great look-back capabilities will be that it will probe the early universe in the infrared, he noted. Arenberg observed that all parts of the universe are moving away from us and the more distant from us an object is, the faster it is moving away. As objects move away at high speeds, the light from them is shifted into the infrared. So to see the most distant objects--those first galaxies--it's necessary to see in the infrared. According to Arenberg, "The JWST will see small faint objects in the infrared anywhere in the sky." It will also be used to study exoplanets and the solar system, and will be able to look through dust clouds. Arenberg is the design integration lead on the telescope. His team must make sure that various systems, which have been in development since 1989, work together. The JWST is a joint development of NASA, the European Space Agency, Canada and numerous other participants. Because it's being designed to see very faint distant objects, the JWST must be very stable. Since, at 1 million miles, it will be too far from Earth to be serviced, there will be no service calls as with the Hubble. The team will design and build so JSTW is "affordable and long lived, the best possible deal for the taxpayer." It


What's Up
By Tony Hoffman The Sky for March 2010
Saturn's Equinoctial Opposition. This year, the spring equinox falls on March 20. The following day, Saturn reaches opposition in Virgo, and is at its closest and brightest of the year. Still, at magnitude 0.5 it's not particularly bright. That's because Saturn's rings are still nearly edge-on to our line of sight, tilted a mere 3 degrees. Titan, Saturn's largest moon, should be visible in even a 2-inch telescope, and I can see several more moons in my 4-inch refractor. Two constellations over, in Cancer, Mars is still brilliant at magnitude -0.6 as the month opens. Its disk spans 12 arc-seconds. By month's end, it will have shrunk to 9, meaning that you'll need a 8-inch or larger scope to hope to resolve much detail on the surface. Minor planet 4 Vesta, which last month "threaded the needle" between Gamma Leonis and the star's 4thmagnitude companion, remains in the vicinity of Gamma Leonis for most of March. By month's end the asteroid, which at magnitude 6.8 is still an easy binocular object, moves to within a degree of Epsilon Leonis. Venus continues its slow climb out of the evening twilight. By month's end it shines at magnitude -3.9 and sets an hour and a half after the Sun. In the last week of the month, Venus is joined by Mercury, at the start of its best evening apparition of the year. On March 31, Mercury lies just 3 degrees from Venus and will shine at magnitude -1.0. March 2 Moon lies near Saturn. March 7 Last-quarter Moon at 10:42 a.m. March 15 New Moon at 5:01 a.m. March 17 Moon lies 7 degrees from Venus. March 20 Vernal equinox at 1:32 p.m. March 21 Saturn at opposition. March 23 First-quarter Moon at 7 a.m. March 25 Moon lies near Mars. March 28 Moon at perigee, 224,859 miles from Earth, 12:59 a.m. March 29 Moon lies near Saturn; full Moon at 10:25 p.m.
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Mars and Moon Shone Bright
By Joseph A. Fedrick
During the nights of January and the first half of February, Mars and the Moon shone bright, although the frost was cruel. Mars was gleaming bright in my 60mm refractor at 100x when I glimpsed a large, fairly well defined dark gray triangular area, Syrtis Major on the coral pink Martian disk, on the mornings of January 20 and 21 from 6:30 a. m. to 7 a. m. The north polar cap was also visible. On the evening of January 29, an unusually bright and large full Moon shone about 7 degrees to the right of Mars. The 100x eyepiece of my 600 refractor revealed faint gray vague markings on the Martian surface. The image of Mars shimmered in the turbulent, chilly night air. Mars was especially bright because it was at opposition from the Sun and closer than it would subsequently be during the rest of the year. The Moon was especially bright and loomed large in the night sky because it was at perigee, the closest part of its elliptical orbit around the Earth. The turbulent, often cloudy winter sky has yielded few views of the Moon and planets so far this year because stormy weather continued almost unabated.

Martin Rees to Speak in New York
Sir Martin Rees, one of the world's most noted cosmologists and astrophysicists, and astronomer royal of the United Kingdom, will speak on "From Big Bang to Biosphere" Monday, April 26 at the Caspary Auditorium of Rockefeller University, 1230 York Avenue (66th Street). The 5:30 talk is free and open to the public. Sir Martin, professor of cosmology and astrophysics at Cambridge, is giving the university's Lewis Thomas Prize for Writing about Science lecture. He received the prize last year. It honors those who bridge the worlds of science and literature with a vision that speaks to science's aesthetic and philosophical dimensions. Sir Martin, Steady State t the Big Bang, a 50% chance whose research helped challenge the heory of the universe's origin in favor of is also controversial. He's given humanity of surviving this century.


A Message from AAA President Richard Rosenberg
Hello, members: As you may have seen on the back page, if you don't renew your membership this will be your last issue of Eyepiece. At only $25 per year, with the opportunity to get subscriptions to Sky & Telescope and Astronomy magazines at substantially reduced rates and Eyepiece for free, I'd say this is quite a bargain. We will be sending a mailing to non renewed members shortly, but I hope you'll respond now with a check or money order sent to Amateur Astronomers Association, P.O. Box 383, Gracie Station, New York, NY 10028. Use the stamped return envelope we sent. The spring AAA astronomy class has been tentatively scheduled for Wednesdays April 7 through May 12. A few of us are working on the syllabus. Expect an announcement in a few weeks. "The Pluto Files" will air on PBS on Tuesday, March 2 at 8 p. m. Based on Neil Tyson's book of the same name, the show will no doubt be a mixture of science and humor (Jon Stewart and Stephen Colbert will appear). Shoba Bandi Rao has resigned from our board of directors, as she has taken on added responsibilities at NYU. Shoba made it possible for our seminar to move to NYU, with participants from both organizations. We'll miss her on the board, but she will remain an active member. Fittingly, she will be replaced by Gerceida Jones. Gerceida is also a faculty member at NYU, teaching astronomy in the Global Liberal Studies program. Her group will now host our seminar. Gerceida has a Ph.D. in fluid dynamics from NYU. We're looking forward to working with her. Rich Rosenberg, AAA President, president @aaa.org, (718) 522-5014

AAA Lecture March 5: The Contributions of Galileo
John S. Gianforte, owner-director of the Blue Sky Observatory in Durham, N. H., will address the AAA Friday, March 5 on "In the Footsteps of the Master: Discovering the Contributions of Galileo." The free public lecture begins at 6:15 p. m. in the Kaufmann Theater of the AMNH. Gianforte will explore Galileo's contributions and some lesser-known motivations for his scientific pursuits that ultimately led to the accomplishments with which amateur astronomers are most familiar. He'll also cover some astronomical history to illustrate how the stage was set for Galileo to make the contributions he did, when he did. In 2008, Gianforte and his wife, Doris, went to Italy to follow in Galileo's footsteps. They visited many places where Galileo lived and sought to get an idea of what it was like in the 17th Century and the influences on Galileo that led to his contributions to astronomy and to science in general. Gianforte is also a physics instructor at the University of New Hampshire and an astronomy instructor at Granite State College. His main astronomical-research interests are transits of extrasolar planets, cataclysmic variable stars, comets and supernovae. He writes on astronomy on his web site, www.theskyguy.org. The two remaining lectures in the AAA's 2009-10 series are April 9 and May 7. In April, Glynnis Farrar of NYU will discuss "High-Energy Astrophysics with a Neutrino Telescope in New York City." In May, Ruben Kier of Advanced Radiology Consultants will speak on "Best Targets for Amateur Astrophotography and What They Reveal about Our Universe."

The AAA's Annual Meeting Is on Wednesday, May 19. Plan on coming!
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The Multiple Advantages of Liquid-Mirror Telescopes
By Lynn Darsh
Why spin a giant vat of mercury with a circumference of 20 meters at eight revolutions a second in a British Columbia rain forest? To demonstrate an inexpensive large survey telescope can be built with no sacrifice of scientific benefits, that's why, as Dr. Arlin Crotts, professor of astronomy at Columbia University, outlined in an AAA lecture February 5 at the AMNH, "Liquid Mirror Telescopes are Looking Up." What's more, this design is well-suited to gather data needed to refine understanding of the expansion rate of the universe and elusive dark energy. Crotts explained that liquid mercury spinning in a uniform gravitational field will rise up on the sides of its container into a parabolic shape, creating a "Newton's Bucket," similar in design but not in materials to the mirror (or "light bucket") of the classic reflecting telescope designed by Isaac Newton. The spinning 6-meter dish is the only substantial moving part of the Large Zenith Telescope (LZT). At a cost of $900,000 for the building, mount and instruments, the LZT was designed and built by scientists from different universities, many of whom live in British Columbia near this largest of "backyard telescopes." Crotts described plans to build an 8-meter version of this inexpensive 6-meter prototype, if $25 million in additional funding can be obtained. The "ALPACA" (Advanced Liquid-mirror Probe of Astrophysics, Cosmology and Asteroids) would be placed at Cerro Telolo in the Chilean Atacama desert. A zenith telescope at Cerro Telolo would be wellpositioned to survey the sky and discover hundreds of thousands of Type IA Supernovae (SN Ia) in distant galaxies, as well as asteroids in our solar system. The study of more of these exploding stars is key to refining their use as "standard candles" in mapping the expansion rate of the universe to better understand dark energy. SN Ias could become a reliable equivalent of the Cepheid variables on a larger distance scale. The advantages of a liquid-mirror telescope are huge.
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A zenith survey telescope requires a building with a hole in the roof and a stable floor to sit on instead of a complex observatory and rotating mount. Neither filter wheels, shutters or dome are required, although steady rotation of the liquid-mercury mirror is a must. (The focal length of the mirror is affected by changes in rotational speed, degrading the image.) CCDs for the ALPACA would be scientific quality, off-the-shelf components; 240 of them can be obtained for about $5 million. Comparative telescopes using more traditional mirrors can easily be 20 times more costly. While the Large Synoptic Survey Telescope (LSST) could do the work planned for a liquid-mirror scope, as well as much else, it would cost $500 million. Plans have been frozen for three years as part of a budget cut. The ALPACA would not be able to compete with the Keck or the upcoming Webb telescopes in the detail of its images, Crotts observed. But it will be a large telescope built at a fraction of the cost, tailored to an observing program of supernovas and asteroids well-suited to its capabilities. Crotts outlined technical challenges overcome in building the LZT. Since vibration from mirror-cell movement caused waves in the mercury, scientists built a "giant air bearing" to hold the mirror cell, eliminating vibration. The rotating liquid mirror created turbulence in the air above the circumference, affecting viewing. Designers reduced turbulence by placing Mylar with a low incidence of refraction over the mercury, trapping the air under it to rotate along with the mirror. The proposed telescope will use "drift scanning," like the Sloan Digital Sky Survey. The scope will match sidereal motion of the sky above the zenith-pointing telescope exactly, with the CCD sensor collection sequencing data into each storage area. Thus, all photons coming from a single source will be captured by different CCDs as the Earth rotates the telescope under the sky, until the object "drifts" out of the field of view. Using mercury this way doesn't pose a safety threat, Crotts told the audience.


Mars Society President Says Go to the Planet First
By John Delaney
What does Dr. Robert Zubrin, president of the Mars Society, think of plans for human spaceflights to the Moon and Mars? The originator of the Mars Direct plan to reach Mars spoke in September at the Hayden on the topic. Eyepiece caught up with Zubrin, who's on this month's Asimov panel at the AMNH (see page 11), for his opinions on the significance of Mars and the future of humans in space. Eyepiece: Regarding the [now cancelled] Constellation program and its mission to return to the Moon and then Mars, [did] you see such a mission as a logical step in eventually reaching Mars? Zubrin: I disagree with the entire logic. If you want to go to Mars, that's where you should go, because that's where the science is, it's where the challenge is, it's where the future is. There are an infinite number of potentially useful precursor activities one could propose to do before you send humans to Mars. If you do all of them or even a small fraction of them, you never get to Mars. It's like the space station. Trust us [they said], it will be useful when you actually decide to go somewhere. Well, lo and behold, it has nothing to do with going to the Moon. Eyepiece: What would be an effective way to present or sell a Mars mission in the current political and economic climate? Zubrin: Any number of ways. As a stimulus to the economy and education. Also, if one wants to deal with the threat of irrationalism in the world, one way to counter it is to show what a civilization based on science, progress and freedom can accomplish. It could also be viewed as a way for America to reassert its spirit of cultural optimism as a nation that can take on any challenge. Eyepiece: What would be the philosophical benefits of a trip to Mars? Zubrin: There are three reasons Mars is the Rosetta Stone in terms life in the universe. We now know water on its surface for substantial the conjecture, generally accepted to go to Mars. First, of the prevalence of that Mars had liquid periods of time, and although not proven, is a process that emerges wherever you have appropriate physical and chemical conditions. If that's correct, life should have emerged on Mars and we'd be able to at least find fossils on the surface. Not only that, there's almost certainly liquid groundwater underground. If we could bring that up and examine it we could see what Martian life is like. Second, the challenge. I believe civilizations are like individuals. We grow by challenging ourselves. Embracing the challenge of a Mars mission for exploration would be a great challenge. Among youth, it would be an invitation to adventure. Learn the science and you can be a part of pioneering and exploring a new world. We had that with Apollo. Finally, there's the future, which is the hardest for us to appreciate but which will ultimately be why this is understood to be a great thing. If we do what we can in our time, which is establish the first human foothold on Mars, 500 years from now there will be several new branches of civilization on Mars. Eyepiece: Do you think you will see humans on Mars in your lifetime? Zubrin: Yes I do [Zubrin is 57], because we're ready to do it. This thing is available and it waits for someone to seize the moment, and sooner or later, we will. Eyepiece: When a human mission to Mars finally happens, where should we go based on our current knowledge of the planet gathered from orbiters and rovers? Zubrin: My favorite area is north of the Valles Marineris. Because it's in an equatorial region, you have lots of sunlight, a warmer climate and lots of interesting geology within a short distance. You get the canyon, run-off channels and dried-up lakes. You want to go where there's a variety of things to explore, including obviously the search for life and water. Another way to direct a search: There's evidence of methane vents on Mars. Go there, because that methane is coming from underground and there are only two possible sources. One is biological, the other hydrothermal. If we go [to the vents], that's 5 an excellent place to look for extant life.


Going Under The Dome and Out of This World
By Evan Schneider
Nothing goes faster than the speed of light--except my recent experience and thorough enjoyment of the February 2 program at the Hayden Planetarium, "Virtual Universe--The Farthest Reaches of the Cosmic Ocean," presented by AAA board member Jason Kendall. I was treated to an insider's perspective, invited to observe Jason and his electronic sky pilot, the AMNH's Jackie Faherty, as they prepared for 100 attendees to join them on a digital trip across the universe. I've been to many planetarium events, but never behind the scenes. So when I reached the doors of the dome, I was filled with excitement, knowing I was about to enter a world of endless perspective and wonderment. I opened the door slowly, not wanting to disturb Jason as he prepared, entered a room of total silence and darkness, and craned my neck skyward. Hovering above me was a huge image of Earth, slowing rotating on its axis. I stood still, transfixed by this image, savoring my moment alone in space. I saw Jason and Jackie in the control booth, preparing their digital world for the audience that would soon follow me through the door. I blended into the darkness, watching our NASA JPL solar-system ambassador work through the largest dataset of any U. S. planetarium, formulating his approach on how and where to fly. His goal was rationalizing the vastness of the universe and having us leave knowing much more than before. At last, he determined his direction: start with the astrological and mythological world by displaying Scorpio, Pisces, Taurus and Leo; show the stars behind these images; perceive distances; display the Magellanic Clouds, and small and large satellite galaxies near the Milky Way. Talk about how fast light travels: less than a second and a half from us to the Moon, four hours from Neptune. Then the Voyager 1 and 2 missions, the farthest we've gone at 17 miles per second yet now only 14 light-hours from Earth. Pull out to 100,000 light-years away. Then look back from our Sun to the center of the Milky Way, separated by only 26,000 light-years. Let's fly through our galactic neighborhood. Andromeda so close at 2.2 million light-years. Then M33, the
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Triangulum Galaxy, at 2.4 million light-years. But Jason wanted us to go even farther, so we travel to the remote Virgo Cluster, a massive collection of 2,000 galaxies 60 million light-years away. Now, distances approach the incomprehensible, and overwhelm. We accept the fact that stretching our imagination to align with complexities of the data takes us to places we've never visited by probe or will ever visit in person. Jason's voice was filled with excitement. We need to go farther, he tells Jackie. I looked toward the dome ceiling and was surrounded by an image of the cosmic microwave background radiation, The age of the universe is 13.7 billion years, but due to expansion of space we can observe objects considerably farther away. The edge of the observable universe is now about 46.5 billion lightyears away. There are no galaxies here, no stars, no solar systems, only gas and dust in blurs of ancient invisible light. We can go no farther. Jason takes us back through billions of light-years to our familiar spiral Milky Way, then home to Earth. Mesmerized by Jason's voice and the dome above, I suddenly realized two hours had passed. The auditorium was still empty. I had flown to the edge of the observable universe and back, and the presentation had yet to begin. The moment had come for Jason to share our private universe with those waiting to come in. The dome lights came up slightly. The doors opened and people pressed into their seats. Expectation filled the room, this time by looking upward at the Earth, now rotating again on its axis for all to see. I sat in my seat and smiled, still in darkness, knowing that those around me were about to embark on the ride of their lives, to share with Jason his energy and vision of the universe, to fill themselves with the knowledge that we are but a small part of a wonderful, dynamic cosmos.

Geoffrey Burbidge Dies at 84
Geoffrey Burbidge, the renowned astronomer who sought to explain how everything derived from stardust, and who was a critic of the Big Bang theory, died January 26 at 84.


AMNH Marks Rose Center's 10th Anniversary
The AMNH is holding a year-long celebration of the 10th anniversary of the Rose Center for Earth and Space. It will include special space-show screenings, a star-themed sleepover, lectures by scientists from the museum's Division of Physical Sciences and elsewhere, and programs in cooperation with NASA, culminating in a 10th anniversary bash October 10. This year also marks the 75th anniversary of the opening of the Hayden Planetarium. A celebration will be held in September. Plans to usher the Rose Center into its second decade include a new Astro Bulletin using cuttingedge display technology, an overhauled Black Hole Theater presentation in the Hall of the Universe and a revitalized Big Bang presentation in the lower half of the Hayden dome featuring imagery and narration that take visitors on a trip back to the birth of the universe and reveal modern cosmology's understanding of the nature of the cosmos. There will also be a "From the Edge of the Universe" lecture series highlighting the latest cutting-edge astrophysics research at the museum. "Tweet-Up to the Stars" will allow visitors to use tweet live with astronauts in the International Space Station. A summer solstice celebration June 20 on the Arthur Ross Terrace will feature hands-on activities including solar-powered car races, solar print making and solar telescope observations. Special programming will commemorate the signing of the historic agreement between the museum and the Confederated Tribes of the Grand Ronde Community of Oregon 10 years ago. This ensured access to the 15.5-ton Willamette Meteorite, the largest meteorite ever found in the U. S. and a centerpiece of the Cullman Hall of the Universe, by the Grand Ronde for religious, historical, and cultural purposes. The 73rd annual meeting of the Meteoritical Society in New York will include a premeeting workshop at the museum July 24-25 to explore the link between understanding of protoplanetary disks and evidence from extraterrestrial materials.

Speaker Discusses Trends in Astrophotography
Astrophotographers are stacking longer exposures, bringing out details never before seen, a Westchester audience recently heard. Douglas Baum, president of Pound Ridge, N. Y.-based Night Vision Astronomy, who spoke as part of a panel at the Rye Arts Center in conjunction with a Hubble photo exhibit, also noted that new large-format chips in cooled CCD cameras have transformed amateur imagers' ability to reach new levels since chips keep getting bigger. Baum explained the concept of stacking exposures and tried to convey the excitement and success experienced by astronomy imagers as they bring out details in their images during image software processing. Baum explained the types of cameras used by amateur astronomers, such as digital single-lens reflex (DSLR) vs. CCD, as well as techniques of real vs. false color. DSLR is the digital version of the old standard single-lens reflex (SLR) camera people use all the time. Baum outlined the differences between luminance green and blue (LRGB) color versus narrow-band tered images, with colors assigned to molecular chemical compositions selectively filtered using H-al OIII and SII filters at various band passes. red, fi l and pha,

There are four separate filters used in a black-andwhite astronomy CCD camera, he noted. "You can take a monochromatic (black and white) exposure through each filter and combine them to produce a full-color image. It has an advantage over one-shot color cameras, which take a single-color exposure without any filters. The advantage is that the black-and-white camera will reach deeper and produce more details, although it must be used with the filters to combine all four exposures into a final color image." Baum also asserted that narrowband is coming into the mainstream. "It allows us to image in light-polluted environments and we can image when a full Moon is up, Astrophotography continued on page 14
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Life Faces a Dangerous Future if Steps Aren't Taken
By Katherine Avakian
Two fundamentally different theories of how life functions on Earth are the subject of Peter Ward's book "The Medea Hypothesis." In a January 11th Hayden lecture on the subject, he explained why he believes Medean rather than more benevolent Gaiaian effects have shaped the course of life on Earth since its inception, and he warned of very real dangers to life in the near future if drastic steps aren't taken. Ward, professor of biology, and Earth and space sciences at the University of Washington, and an astrobiologist with NASA, chose Medea, the Greek mythological figure who killed her children, as a destructive symbol, saying, "...a characteristic of evolution is that its basic unit is the species, not the biosphere, and from this accrues a vicious...lethality toward other species...." This view is countered by James Lovelock's Gaia hypothesis, named for the Greek goddess of the Earth, which espouses the view, "Earth is a complex, selfregulating system, and living things carry out this regulation." Ward contradicted this view, pointing out examples where living things caused destruction of other life. The rise of oxygen 2.5 billion years ago by appearance of photosynthetic microbes caused near-extinction of the organisms which had been living in an anaerobic world until then. These photosynthetic organisms, which greatly increased in number, caused the first snowball Earth 2.3 billion years ago by using up the carbon dioxide in the atmosphere, causing Earth's temperature to plunge, freezing the planet "from pole to pole." In his book, Ward declares this episode "was perhaps as close to planetary sterilization as we have ever gotten." He writes about an especially insidious event which he thinks will happen when global warming inexorably produces "global stagnation...no heat gradient from equator to pole, no currents or wind. Without currents, a warmed ocean loses its oxygen, from the bottom up." In these conditions, certain bacteria in the sea which metabolize sulfur can multiply greatly. The byproduct they give off is the poisonous gas hydrogen sulfide:
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"Two hundred ppm will kill you, 50 ppm will make you very sick." If this gas enters the atmosphere from the sea, it will "gruesomely kill off most land life, especially plant life." Ward says this has already happened at least eight times. Ward points out that the amount of atmospheric carbon dioxide plays a crucial role in regulating Earth's temperature. This amount has trended downward from the time vascular plants evolved 400 million years ago to the present-day level of 380 ppm. This happened due to photosynthesis and "through removal of carbon dioxide from the atmosphere to carbonate reservoirs on continents," such as the Rockies or the Alps. In the long run, for plants to survive, carbon will have to be returned to the atmosphere, perhaps, says Ward, through "some kind of heating of limestones on a massive scale." Paradoxically, at present, the amount of carbon dioxide is increasing and the threat of runaway global warming looms due to burgeoning human populations and a lifestyle dependent on fossil fuels. Ward lists severe conservation measures: "Simply by replacing the entire fleet of the world's automobiles with Toyota hybrids, replacing all light bulbs with low energy fluorescents, and banning all air travel would rather quickly stabilize atmospheric carbon dioxide values...." Knowing that these measures won't willingly be undertaken, he appears to underscore a