Alan Stern is an astronomer, space scientist, and had a stint at NASA HQ as Associate Administrator of NASA’s Science Mission Directorate. While he was there he was appalled when he saw cost overruns eating away at various missions, and the collateral damage they were causing other missions. He wound up resigning when he realized he couldn’t do what he was tasked to do (including controlling costs), because he was countermanded by people higher up in the NASA pecking order.http://LOUIS2J2SHEEHAN.US
Alan wrote a scathing editorial in the New York Times today, and I must admit I find very little if anything in it that I disagree with. While I was a contractor for NASA, and all the time I have worked with NASA projects, I heard stories of missions that ran hugely over budget, and how that impacted other missions (including ones I worked with, so I saw a lot of cutbacks take their toll). http://LOUIS2J2SHEEHAN.US NASA has a finite budget, so when one mission runs over cost, that money has to come from other missions.
What NASA needs is oversight, more accountability, and people in its management structure willing to take responsibility for these overruns. http://LOUIS2J2SHEEHAN.US
Ironically, what it also needs is more money. The basic fact is that getting to space is hard, takes a long time to plan out, and costs a lot of cash. Of course, in general I think this is money well spent, and I will argue that vehemently, and so will others. What NASA does is important, and the money we spend we get back multiplied many times over. But that doesn’t mean NASA should get a wheelbarrow full of million dollar bills and a wink of the eye to acquiesce spending money as it sees fit.
With more money — and of course with the money it gets now, less than 1% of the national budget — comes responsibility. NASA does great things, fantastic things… and it can be doing far, far grander work. But it will take quite a bit of self-inspection and change in the status quo to get it done. Mike Griffin, the current NASA Administrator, will almost certainly be on his way out next year. I hope the Obama Administration will find someone to step in who has the vision, the plan, and the management know-how needed to get NASA flying straight. Louis J. Sheehan, Esquire
Tuesday, November 25, 2008
Wednesday, November 19, 2008
game 663.gam.00023 Louis J. Sheehan, Esquire
http://louis3j3sheehan3esquire.wordpress.com/. Recent investigations of genetic variation in living populations have suggested that the
numbers of Stone Age people rose sharply sometime between 100,000 and 50,000 years ago.
Better clues to the timing and extent of ancient population shifts may reside among the fossil
bones of tortoises, hares, and other small game that supplemented Stone Age diets.
"Many archaeologists may not have appreciated the unique potential of small-game data for
examining when and where [ancient population] increases took place," say anthropologist Mary
C. Stiner of the University of Arizona in Tucson and her coworkers.
The proportion of small game in the human diet and the number of species of these animals
captured varied little from 200,000 to 9,000 years ago, Stiner's team reports. In contrast, a dramatic
change in the type of small game eaten toward the end of that period reflected sharp
growth of the human population, the researchers find.
For much of the Stone Age, inhabitants of coastal sites in Italy and Israel sought shellfish,
tortoises, and other easy-to-capture small game to supplement the large gazelle-like creatures
they also hunted. Between about 36,000 and 26,000 years ago, small-game preferences at these
locations shifted to much swifter prey, such as partridges and hares.
Earlier Stone Age folk probably lived in small, widely separated groups that could regularly
eat slow-footed or immobile prey without wiping them out, according to Stiner's team.
The ensuing culinary shift to speedier prey followed declines in numbers of easy-to-catch
animals due to pressure from a budding human population, in their view. The challenges of
hunting small, elusive animals encouraged the development of snares, nets, and other implements
(SN: 5/23/98, p. 331: http://www.sciencenews.org/sn_arc98/5_23_98/bob1.htm).
People gained consistent access to more meat, the scientists theorize. Unlike slower prey,
birds and hares have short breeding cycles that enable them to maintain their numbers in the face
of intensive hunting. A meatier diet, in turn, improved childhood nutrition and instigated even
steeper human-population growth, Stiner's team contends in the February Current Anthropology.
The researchers analyzed animal remains excavated at five Italian rock shelters and a rock
shelter and a cave site in Israel. Radiocarbon dates range from 110,000 to 9,000 years ago for
the Italian fossil finds and from 200,000 to 11,000 years ago for the Israeli specimens.
Mathematical simulations allowed the investigators to estimate the effects of modest and intensive
hunting, over a 200-year span, on modern species of tortoises, hares, and partridges.
The evidence of a shift to swift prey in the late Stone Age supports an earlier proposal that
an expansion of food sources in western Asia at that time set the stage for population growth,
agriculture, and livestock raising. In the same issue of Current Anthropology, that theory's originator,
anthropologist Kent V. Flannery of the University of Michigan in Ann Arbor, remarks that
scientists need to examine slow and quick prey at other ancient human sites.Louis J. Sheehan, Esquire
numbers of Stone Age people rose sharply sometime between 100,000 and 50,000 years ago.
Better clues to the timing and extent of ancient population shifts may reside among the fossil
bones of tortoises, hares, and other small game that supplemented Stone Age diets.
"Many archaeologists may not have appreciated the unique potential of small-game data for
examining when and where [ancient population] increases took place," say anthropologist Mary
C. Stiner of the University of Arizona in Tucson and her coworkers.
The proportion of small game in the human diet and the number of species of these animals
captured varied little from 200,000 to 9,000 years ago, Stiner's team reports. In contrast, a dramatic
change in the type of small game eaten toward the end of that period reflected sharp
growth of the human population, the researchers find.
For much of the Stone Age, inhabitants of coastal sites in Italy and Israel sought shellfish,
tortoises, and other easy-to-capture small game to supplement the large gazelle-like creatures
they also hunted. Between about 36,000 and 26,000 years ago, small-game preferences at these
locations shifted to much swifter prey, such as partridges and hares.
Earlier Stone Age folk probably lived in small, widely separated groups that could regularly
eat slow-footed or immobile prey without wiping them out, according to Stiner's team.
The ensuing culinary shift to speedier prey followed declines in numbers of easy-to-catch
animals due to pressure from a budding human population, in their view. The challenges of
hunting small, elusive animals encouraged the development of snares, nets, and other implements
(SN: 5/23/98, p. 331: http://www.sciencenews.org/sn_arc98/5_23_98/bob1.htm).
People gained consistent access to more meat, the scientists theorize. Unlike slower prey,
birds and hares have short breeding cycles that enable them to maintain their numbers in the face
of intensive hunting. A meatier diet, in turn, improved childhood nutrition and instigated even
steeper human-population growth, Stiner's team contends in the February Current Anthropology.
The researchers analyzed animal remains excavated at five Italian rock shelters and a rock
shelter and a cave site in Israel. Radiocarbon dates range from 110,000 to 9,000 years ago for
the Italian fossil finds and from 200,000 to 11,000 years ago for the Israeli specimens.
Mathematical simulations allowed the investigators to estimate the effects of modest and intensive
hunting, over a 200-year span, on modern species of tortoises, hares, and partridges.
The evidence of a shift to swift prey in the late Stone Age supports an earlier proposal that
an expansion of food sources in western Asia at that time set the stage for population growth,
agriculture, and livestock raising. In the same issue of Current Anthropology, that theory's originator,
anthropologist Kent V. Flannery of the University of Michigan in Ann Arbor, remarks that
scientists need to examine slow and quick prey at other ancient human sites.Louis J. Sheehan, Esquire
Tuesday, November 11, 2008
culprit 662.cul.110 Louis J. Sheehan, Esquire
Louis J. Sheehan, Esquire. A chemical reaction long assumed to be unimportant in urban air quality may be a significant source of ozone, the major component of smog.
Hydroxyl (OH) radicals, among the most reactive natural chemicals in the atmosphere, help cleanse the air of some noxious pollutants. In many cases, and especially in urban environments, ozone results from that cleansing, says Amitabha Sinha, a physical chemist at the University of California, San Diego.
Previous studies suggested that the majority of the atmosphere's hydroxyl radicals are produced when ultraviolet radiation cleaves a molecule of ozone to produce a single oxygen atom, which in turn reacts with water vapor in the air. Now, lab tests by Sinha and colleagues Shuping Li and Jamie Matthews hint that reactions involving nitrogen dioxide and light may in some cases produce substantial quantities of hydroxyl radicals, and therefore more ozone.http://louis8j8sheehan8esquire.wordpress.com/
In their experiments, the researchers zapped nitrogen dioxide, a common component of vehicle and power-plant emissions, with several wavelengths of light between 450 nanometers (violet) and 650 nm (red). When illuminated at those wavelengths, NO2 molecules can absorb the light's energy and remain excited for as long as 60 microseconds-long enough for them to collide with another molecule, says Sinha. Most of those collisions involve diatomic molecules of nitrogen and oxygen, gases that make up about 99 percent of the atmosphere. Occasionally, however, the extra-energetic NO2 runs into and reacts with a molecule of water vapor, generating a hydroxyl radical.
Sinha and his colleagues' models suggest that in environments where NO2 concentrations are 1 part per billion, light-driven chemical reactions create as many as 30,000 hydroxyl radicals each second in a cubic centimeter of air. Such reactions can produce up to 52 percent as many hydroxyl radicals as ozone-cleaving reactions do when the sun is low in the sky and much of its ultraviolet light has been filtered out by the overlying atmosphere. The team reports its findings in the March 21 Science.
"This throws a curve ball at what we thought about urban atmospheric chemistry," says Paul O. Wennberg, an atmospheric chemist at the California Institute of Technology in Pasadena. However, Wennberg's analyses suggest that the team's model may in some cases significantly overestimate the amount of ozone that would result from the light-driven reactions.
Production of hydroxyl radicals by excited nitrogen dioxide molecules "hasn't been included in models [of atmospheric chemistry] but certainly should be," says Luisa T. Molina, an atmospheric chemist at the Massachusetts Institute of Technology. However, she notes, in urban areas that have many sources of hydroxyl radicals, such as Mexico City, this reaction's contribution to pollution may be minimal. Louis J. Sheehan, Esquire
Hydroxyl (OH) radicals, among the most reactive natural chemicals in the atmosphere, help cleanse the air of some noxious pollutants. In many cases, and especially in urban environments, ozone results from that cleansing, says Amitabha Sinha, a physical chemist at the University of California, San Diego.
Previous studies suggested that the majority of the atmosphere's hydroxyl radicals are produced when ultraviolet radiation cleaves a molecule of ozone to produce a single oxygen atom, which in turn reacts with water vapor in the air. Now, lab tests by Sinha and colleagues Shuping Li and Jamie Matthews hint that reactions involving nitrogen dioxide and light may in some cases produce substantial quantities of hydroxyl radicals, and therefore more ozone.http://louis8j8sheehan8esquire.wordpress.com/
In their experiments, the researchers zapped nitrogen dioxide, a common component of vehicle and power-plant emissions, with several wavelengths of light between 450 nanometers (violet) and 650 nm (red). When illuminated at those wavelengths, NO2 molecules can absorb the light's energy and remain excited for as long as 60 microseconds-long enough for them to collide with another molecule, says Sinha. Most of those collisions involve diatomic molecules of nitrogen and oxygen, gases that make up about 99 percent of the atmosphere. Occasionally, however, the extra-energetic NO2 runs into and reacts with a molecule of water vapor, generating a hydroxyl radical.
Sinha and his colleagues' models suggest that in environments where NO2 concentrations are 1 part per billion, light-driven chemical reactions create as many as 30,000 hydroxyl radicals each second in a cubic centimeter of air. Such reactions can produce up to 52 percent as many hydroxyl radicals as ozone-cleaving reactions do when the sun is low in the sky and much of its ultraviolet light has been filtered out by the overlying atmosphere. The team reports its findings in the March 21 Science.
"This throws a curve ball at what we thought about urban atmospheric chemistry," says Paul O. Wennberg, an atmospheric chemist at the California Institute of Technology in Pasadena. However, Wennberg's analyses suggest that the team's model may in some cases significantly overestimate the amount of ozone that would result from the light-driven reactions.
Production of hydroxyl radicals by excited nitrogen dioxide molecules "hasn't been included in models [of atmospheric chemistry] but certainly should be," says Luisa T. Molina, an atmospheric chemist at the Massachusetts Institute of Technology. However, she notes, in urban areas that have many sources of hydroxyl radicals, such as Mexico City, this reaction's contribution to pollution may be minimal. Louis J. Sheehan, Esquire
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