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Professor
Shakhashiri is a frequent guest of the Larry Meiller Show
on the Ideas Network of Wisconsin Public Radio.
December 5, 2002 Larry Meiller Show
On the December 5th program, the discussion included the following topics in response to questions raised by host Larry Meiller and to calls from listeners:
Wisconsin Public Television is videotaping the Christmas lecture, "Once Upon a Christmas Cheery in the Lab of Shakhashiri". The program will be shown on Wisconsin Public Television on Christmas day at 4PM and again December 29th. at 8am. A shorter version will be available to public television stations throughout the country to show anytime they wish.
The United States Patent and Trademark Office is celebrating its 200th anniversary. It is estimated that 52 per cent of the nation's growth since World War II has come through invention. Future innovation depends on giving children the tools to think creatively and the motivation to invent. The government and society as a whole should try to ensure that the pace of innovation does not slow down.
The scientific community and the federal government are struggling with the question of balancing national security and scientific openness. Would we be safer to restrict the flow of scientific knowledge in certain fields? Would that reduce our economic vitality? This is a political question which the public must ultimately decide..
November 7, 2002 Larry Meiller Show
On the November 7th program, the discussion included the following topics in response to questions raised by host Larry Meiller and to calls from listeners:
Professor Shakhashiri has received an award from the American Association for the Advancement of Science, the 2003 Award for Public Understanding of Science and Technology. The award is for "tireless efforts in communicating the nature of science to the public" and includes a prize of $5,000.
Professor Shakhashiri's annual Christmas lectures are scheduled for December 7th. and 8th. This is the 33rd. year for the chemistry demonstration/lectures which always play to full houses. They will be at the chemistry building at the University of Wisconsin-Madison.
It was recently reported that French fries may be harmful to health because of a chemical formed in the cooking process. Are French fries safe to eat? For more information, see the October 14 issue of The Scientist.
October 3, 2002 Larry Meiller Show
On the October 3rd program, the discussion included the following topics in response to questions raised by host Larry Meiller and to calls from listeners:
The next day was the 45th anniversary of the launch of Sputnik by the Soviet Union. The launch came as a shock to Americans and stimulated intense new efforts to teach science and math. Professor Shakhashiri says such efforts are even more vital today since science and technology play an even bigger role in society. Not only do we need more scientists, important questions can't be resolved in a democratic way unless the public has a basic understanding of science.
Two recent examples of fraud by scientists have made national news recently. A scientist at the University of California-Berkeley and another at Bell Labs faked data to make their research seem more impressive. Fraud not only misleads other scientists, it casts a shadow over science in general. Professor Shakhashiri says the co-authors of papers and editors of scientific journals must be more vigilant, but notes that the system of review and criticism ultimately worked and uncovered the fraud.
A caller asked whether it would be more efficient to leave a home freezer half empty or to fill it with water bottles. For the answer, see the website of the California Energy Commission.
August 29, 2002 Larry Meiller Show
On the August 29th program, the discussion included the following topics in response to questions raised by host Larry Meiller and to calls from listeners:
Professor Shakhashiri talked about the Wisconsin Initiative for Science Literacy and specifically about one of its programs, Conversations In Science. Conversations in Science brings together high school and middle school science teachers in monthly seminars with top University of Wisconsin researchers.
Earlier this month, Professor Shakhashiri spoke at an international conference in China and gave his impressions of China, its technology and science.
As an example of successful science education, two Madison teenagers won gold medals at the prestigious 43rd. International Mathematical Olympiad. Po-Ru Loh, 17, and Daniel Kane, 16, also earned perfect scores at the U.S Math Olympiad earlier this year, two of only five students to do so.
With the school year about to begin, Larry asked for advice for students and parents. Professor Shakhashiri emphasized the importance of parents in guiding and promoting education.
June 27, 2002 Larry Meiller Show
On the June 27 program, the discussion included the following topics in response to questions raised by host Larry Meiller and to calls from listeners:
The goals of the newly-launched Wisconsin Initiative for Science Literacy. For more information, see the WISL Web page.
Stephen Jay Gould, who died last month at age 60, is remembered as one of the best communicators of science of the past century.
Highly recommended reading: The fascinating books published last year, the first by noted neurologist and author Oliver Sacks, Uncle Tungsten: Memories of a Chemical Boyhood (Knopf), and This Man's Pill: Reflections on the 50th Birthday of the Pill, by Carl Djerassi (Oxford University Press). Dr. Sacks spoke at the UW-Madison Chancellor's convocation last Fall, and Professor Djerassi received his Ph.D. degree in chemistry from UW-Madison.
Stephen Wolfram's book, A New Kind of Science, which is near the top of Amazon's best sellers.
May 2, 2002 Larry Meiller Show
On the May 2 program, the discussion included the following topics in response to questions raised by host Larry Meiller and to calls from listeners:
March 21, 2002 Larry Meiller Show
On the March 21 program, the discussion included the following topics in response to questions raised by host Larry Meiller and to calls from listeners:
The vernal equinox which occurred at 1:16 p.m. yesterday prompted asking the listening audience to think about why there are four seasons. Callers provided the correct answer about the tilt of the earth on its axis of rotation. Other callers asked about the moon and other questions from astronomy.
Responses to the following questions were solicited from and kindly provided by astronomer Frank D. Drake, who is chairman of the board of the SETI Institute http://www.seti.org
Why does the earth tilt? It is believed that all the tilts in the solar system are a result of hits by large objects, most of which hits occurred during the time of "the heavy bombardment", which ended 3.8 billion years ago (sun and Earth are 4.5 billion years old). Uranus and Venus even had their rotations reversed. Pluto maybe, too, although its history is more of a puzzle. The object which collided with Earth to make the moon was almost the size of Mars, and probably caused most of the tilt. The Pacific Ocean may be partially a scar from that event, which was almost powerful enough to demolish the Earth.
Does the moon rotate at the same speed as the earth? That is,
why don't we see the dark side of the moon? Does the moon tilt too?
Interesting story here. First, there is no "dark side" -- a common mistake.
There is a "far side." The appearance of the moon is governed by: (1)
Its rotation period is exactly the same as its orbital period. Thus
we would always see exactly the same face except:( 2) The orbit is elliptical,
and thus the moon moves in its orbit faster at some times than others;
(3) The rotational axis of the moon is tilted 6.5 degrees with respect
to the orbit and 4) The observer is riding on a rotating Earth. This
combination of facts leads to the so-called "librations" of the moon.
There are three always described in modern textbooks:
the moon wobbles slightly (about 7 degrees) from east to west once in
the course of a lunation (roughly a month). This is because the moon
moves at different speeds at different times each orbit. This is the
monthly libration in longitude.
The moon wobbles slightly from East to West, about one degree, in the
typical twelve hours it is visible to any observer. This is because
the observer is carried from one "limb" of the Earth to the other in
those twelve hours, so we are looking toward the moon from a different
position, from a moving platform, so to speak. This is parallax. This
is the daily libration in longitude.
The pole of the moon nods towards us and then away from us (by 6.5 degrees) once in the course of a lunation. This is the monthly libration in latitude.
You can see an animation of these motions as several Web sites, such as www.minervatech.u-net.com/moon/not_libr_ac.htm
Historically, the lunar librations were the last discovery of Galileo. He was very proud of this discovery.
Originally the moon was probably spinning at such a rate that it did not keep one face to the Earth. However, as it spins the gravity of the Earth raises tides in it, even in its solid body (the moon raises tides in the solid body of the Earth of about 9 inches -- these, along with the ocean tides are slowing the Earth down.) The this "kneading" of the moon creates friction which acts to slow down the rotation. Given enough time, this tidal friction changes the rotation period so that there no longer are changing tides. The moon keeps one face toward the Earth. This is a widespread phenomenon, found in every object which is close enough to the object about which it orbits. All the inner satellites of Jupiter keep one face towards Jupiter. All the satellites of Saturn (maybe all of Jupiter's, too -- we don't know) keep one face towards Saturn. So it is not a freakish phenomenon, but occurs wherever there are tides and enough time.
Mercury is also in "locked"rotation with the sun, but in this case, because of the elliptical orbit, the locking does not keep one face toward the sun, but causes Mercury to present alternate faces to the sun very time it comes closest.
A real mystery is that Venus not only rotate backwards, but presents the same face to the Earth every time it passes closest to the Earth. This sounds like the tides in action again, but the numerical calculations indicate that the tides raised by the distant Earth are not sufficient to stop the rotation of Venus, reverse it, and bring about the resonance.
What causes earth's magnetic field to change? A caller
asked if his compass that points N would "switch" and point S?
The Earth's magnetic field is generated by electrical currents in the
Earth, which are in turn generated by random motions of hot, electrically
conducting, molten rock in the interior of the Earth. Much of the interior
is moving like boiling water in a pot, do to heat supplied from the
Earth. The motion is much slower, however, typically a few inches a
year! But this "convection" produces the currents and magnetic field
(as it does in other planets). When the pattern of motions changes,
as in a pot of boiling water, the magnetic field changes. Sometimes
the field even goes to nearly zero, and sometimes it reverses polarity.
And yes, when the polarity changes a compass would reverse the direction
it points.
Why is there a difference between the equinox and the actual time when the daylight and nighttime hours are equal? At the equinox the length of time for the sun to go from the Eastern projected horizon to the Western projected horizon is exactly half a day, or twelve hours (except for a small difference caused by the ellipticity of the Earth's orbit). However, the length of time between sunrise and sunset is longer because the Earth's atmosphere refracts light, causing the sun to appear higher in the sky than it actually is. At the horizon, the atmosphere causes the sun to appear just about half a degree higher. So the sun actually rises earlier than we would expect – we can actually see it when it is still lower than the horizon. Similarly, it sets later than we would expect because the bending of the light from the sun allows us to see it even though geometrically it is below the horizon. It takes about two minutes for the Earth to rotate half a degree. So at the equator the sun rises about two minutes earlier than we might expect, and sets two minutes later than we might expect, causing the length of time the sun is seen above the horizon to be about 12 hours and 4 minutes. At higher latitudes the sun moves along an oblique path at the Earth rotates, and so the sunlight persists even longer than 12 hours and 4 minutes.
My very special thanks to my brother-in-law Frank Drake for the above contributions. Also, I thank David Helander from the listening audience who e-mailed the following link regarding the face of the moon http://www.sciam.com/askexpert/astronomy/astronomy21.html
UW-Madison is the second among research universities in research grants.
Impact of the proposed state budget cuts on the UW-Madison and the UW System
The debate in the state of Ohio about Intelligent Design and the inclusion of creationism in the curriculum. For more information please visit http://www4.nas.edu/opus/evolve.nsf. For the other view point please visit http://www.intelligentdesignnetwork.org/
Don Vincent, a science teacher from Madison West High School was just named, along with 3 other teachers from Wisconsin, a recipient of the Presidential Award for Excellence in Teaching Science and Mathematics.
Intel Talent Search results were recently. Among the top 10 winners is 17 year old Marc Burrell of Nicolet High School in Glendale, Wisconsin.. For more information visit http://www.sciserv.org/sts/press/20020311.asp
January 24, 2002 Larry Meiller Show
On the January 24 program, the discussion included the following topics in response to questions raised by host Larry Meiller and to calls from listeners:
The purposes and features of the Chemical of the Week series used in Professor Shakhashiri's chemistry course. This week's entry is ethyl alcohol. For more information , please visit the Science is Fun Web site.
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