Balloon Mission Tunes in to a Cosmic Radio Mystery
Cool, something new:
NASA - NASA Balloon Mission Tunes in to a Cosmic Radio Mystery
Listening to the early universe just got harder. A team led by Alan Kogut of NASA’s Goddard Space Flight Center in Greenbelt, Md., today announced the discovery of cosmic radio noise that booms six times louder than expected.
The finding comes from a balloon-borne instrument named ARCADE, which stands for the Absolute Radiometer for Cosmology, Astrophysics, and Diffuse Emission. In July 2006, the instrument launched from NASA’s Columbia Scientific Balloon Facility in Palestine, Texas, and flew to an altitude of 120,000 feet, where the atmosphere thins into the vacuum of space.
ARCADE’s mission was to search the sky for heat from the first generation of stars. Instead, it found a cosmic puzzle.
“The universe really threw us a curve,” Kogut says. “Instead of the faint signal we hoped to find, here was this booming noise six times louder than anyone had predicted.” Detailed analysis ruled out an origin from primordial stars or from known radio sources, including gas in the outermost halo of our own galaxy. The source of this cosmic radio background remains a mystery…
Messenger Photo of Mercury
As reported in Sky & Tel, Messenger made a flyby of Mercury on Monday. Here’s an amazing photo from 27,000 km out. (The flyby got to within 200 km.)
Global surface temperature variations during the past 2000 years
From MongaBay, a plot summarizing results from several proxy measures of surface temperature. Temperatures in the past decade are on average higher than during the Medieval warm period. Much more alarming is the extremely high rate of increase during the past few decades.
[plot from Mann et al. (2008). Proxy-based reconstructions of hemispheric and global surface temperature variations over the past two millennia. PNAS September 9, 2008, vol. 105 no. 36]
Largest Rodent Ever
from MongaBay:Scientists have discovered the remains of an extinct 2,000 pound rodent — the largest rodent ever known. The find is described Wednesday in Britain's Proceedings of the Royal Society.
"We report the discovery of an exceptionally well preserved fossil skull of a new species of rodent, by far the largest ever recorded," wrote Andres Rinderknecht and Ernesto Blanco of the National Museum of Natural History in Montevideo.
The authors say that while most present day rodents are small creatures, their discovery reveals that ancient rodents could grow larger than a bull.
 An artist's impression of Josephoartigasia monesi. Courtesy of Gustavo Lecuona/Ernesto Blanco |
The beast, which roamed the South American continent some 2-4 million years ago and is named Josephoartigasia monesi, likely fed on fruit and plant shoots, based on its small teeth and jaw structure.
The world's largest rodent alive today is the capybara found in tropical South America. The semi-aquatic species can weigh 125 pounds (60 kg).
Global Temperature Change
The NAS just published a free-access paper by James Hansen and collaborators, ”Global temperature change”, PNAS, September 26, 2006, vol. 103, no. 39, pp. 14288-14293. Here is the abstract text:
Global surface temperature has increased {approx}0.2°C per decade in the past 30 years, similar to the warming rate predicted in the 1980s in initial global climate model simulations with transient greenhouse gas changes. Warming is larger in the Western Equatorial Pacific than in the Eastern Equatorial Pacific over the past century, and we suggest that the increased West–East temperature gradient may have increased the likelihood of strong El Niños, such as those of 1983 and 1998. Comparison of measured sea surface temperatures in the Western Pacific with paleoclimate data suggests that this critical ocean region, and probably the planet as a whole, is approximately as warm now as at the Holocene maximum and within {approx}1°C of the maximum temperature of the past million years. We conclude that global warming of more than {approx}1°C, relative to 2000, will constitute “dangerous” climate change as judged from likely effects on sea level and extermination of species.
From the paper (SST = sea surface temperature):
Fig. 3. SST in 2001–2005 relative to 1870–1900, from concatenation of two data sets, as described in the text.
Fig. 5. Modern sea surface temperatures in the WEP compared with paleoclimate proxy data. Fig. 5 shows that recent warming of the WEP has brought its temperature within <1°C of its maximum in the past million years.
Growing Acidity of Oceans Kills Corals
from WaPo:
By Juliet Eilperin
The escalating level of carbon dioxide in the atmosphere is making the world’s oceans more acidic, government and independent scientists say. They warn that, by the end of the century, the trend could decimate coral reefs and creatures that underpin the sea’s food web.
Although scientists and some politicians have just begun to focus on the question of ocean acidification, they describe it as one of the most pressing environmental threats facing Earth.
“It’s just been an absolute time bomb that’s gone off both in the scientific community and, ultimately, in our public policymaking,” said Rep. Jay Inslee (D-Wash.), who received a two-hour briefing on the subject in May with five other House members. “It’s another example of when you put gigatons of carbon dioxide into the atmosphere, you have these results none of us would have predicted.”
Thomas E. Lovejoy, president of the H. John Heinz III Center for Science, Economics and the Environment, has just rewritten the paperback edition of “Climate Change and Biodiversity,” his latest book, to highlight the threat of ocean acidification. “It’s the single most profound environmental change I’ve learned about in my entire career,” he said last week.
A coalition of federal and university scientists is to issue a report today describing how carbon dioxide emissions are, in the words of a press release from the National Center for Atmospheric Research and the National Oceanic and Atmospheric Administration, “dramatically altering ocean chemistry and threatening corals and other marine organisms that secrete skeletal structures.”
For decades, scientists have viewed the oceans’ absorption of carbon dioxide as an environmental plus, because it mitigates the effects of global warming. But by taking up one-third of the atmosphere’s carbon dioxide—much of which stems from exhaust from automobiles, power plants and other industrial sources—oceans are transforming their pH level.
The pH level, measured in “units,” is a calculation of the balance of a liquid’s acidity and its alkalinity. The lower a liquid’s pH number, the higher its acidity; the higher the number, the more alkaline it is. The ph level for the world’s oceans was stable between 1000 and 1800, but has dropped one-tenth of a unit since the Industrial Revolution, according to Christopher Langdon, a University of Miami marine biology professor.
Scientists expect ocean pH levels to drop by another 0.3 units by 2100, which could seriously damage marine creatures that need calcium carbonate to build their shells and skeletons. Once absorbed in seawater, carbon dioxide forms carbonic acid and lowers ocean pH, making it harder for corals, plankton and tiny marine snails (called pteropods) to form their body parts.
Ken Caldeira, a chemical oceanographer at Stanford University who briefed lawmakers along with NCAR marine ecologist Joan Kleypas, said oceans are more acidic than they have has been for “many millions of years.”
“What we’re doing in the next decade will affect our oceans for millions of years,” Caldeira said. “CO2levels are going up extremely rapidly, and it’s overwhelming our marine systems.”
Some have questioned global-warming predictions based on computer models, but ocean acidification is less controversial because it involves basic chemistry. “You can duplicate this phenomenon by blowing into a straw in a glass of water and changing the water’s pH level,” Lovejoy said. “It’s basically undeniable.”
Hugo A. Lo?iciga, a geography professor at the University of California at Santa Barbara, is one of the few academics to question the phenomenon. A groundwater hydrologist, Lo?iciga published a paper in the May edition of the American Geophysical Union’s journal that suggested the oceans may not become so acidic, because enough carbonate material will help restore equilibrium to them.
Lo?iciga wrote that although seawater in certain regions may become more acidic over time, “on a global scale and over the time scales considered (hundreds of years), there would not be accentuated changes in either seawater salinity or acidity from the rising concentration of atmospheric CO2.”
Two dozen scientists have written a response questioning this assumption, since it would take thousands of years for such material to reach the oceans from land.
“The paper by Lo?iciga ignores decades of scholarship, presents inappropriate calculations and draws erroneous conclusions that simply do not apply to real ocean,” they wrote. They added that, unless carbon dioxide levels in the atmosphere stabilize soon, the seas will soon exceed the Environmental Protection Agency’s recommended acidity limits.
Scientists have conducted a few ocean acidification experiments in recent years. All have shown that adding carbon dioxide to the water slows corals’ growth rate and can dissolve pteropods’ shells.
Langdon, who conducted an experiment between 1996 and 2003 in Columbia University’s Biosphere 2 lab in Tucson, concluded that corals grew half as fast in aquariums when exposed to the level of carbon dioxide projected to exist by 2050. Coupled with the higher sea temperatures that climate change produces, Langdon said, corals may not survive by the end of the century.
“It’s going to be on a global scale and it’s also chronic,” Langdon said of ocean acidification. “Twenty-four/seven, it’s going to be stressing these organisms. . . . These organisms probably don’t have the adaptive ability to respond to this new onslaught.”
Stanford University marine biologist Robert B. Dunbar has studied the effect of increased carbon dioxide on coral reefs in Israel and Australia’s Great Barrier Reef. “What we found in Israel was the community is dissolving,” Dunbar said.
Caldeira has mapped out where corals exist today and the pH levels of the water in which they thrive; by the end of the century, no seawater will be as alkaline as where they live now. If carbon dioxide emissions continue at their current levels, he said, “It’s say goodbye’ to coral reefs.”
Although the fate of plankton and marine snails may not seem as compelling as vibrantly colored coral reefs, they are critical to sustaining marine species such as salmon, redfish, mackerel and baleen whales.
“These are groups everyone depends on, and if their numbers go down there are going to be reverberations throughout the food chain,” said John Guinotte, a marine biologist at the Marine Conservation Biology Institute. “When I see marine snails’ shells dissolving while they’re alive, that’s spooky to me.”
Rep. Rush D. Holt (D-N.J.), a scientist by training, attended the congressional briefing on ocean acidification. He said these developments are “new to me, which was surprising because I usually keep up with things.”
“The changes in our climate are severe and urgent even if it weren’t for this, but this just adds impact and urgency to the situation,” Holt said.
Trip Report: the 2006 DDA Meeting in Halifax
Note: Apologies for the stilted prose; we are required to write in the third person. This is the original version, before being censored for consumption by unimaginative, humorless drones above my pay grade. Also available here.
Murison gave a contributed paper, "On the Precision of Artificial Satellite Orbit Determination from Observations from an Orbiting Platform". Many in the audience were as captivated as Murison is by the unconventional notion of doing precision astrometry of artificial satellites from a telescope mounted on a low-Earth-orbit satellite (such as the MAPS mission being proposed by USNO). There was general acknowledgement in discussions afterward that the magnitude of difficulty of analytical approximations of the problem is surprising. Apparently, analytical characterization of orbit determination error distributions is a heretofore unvisited problem (as also born out by Murison's searches of the astronomical literature.)
Efroimsky gave a contributed paper, "On the Theories of Bodily Tides: The Models and the Physics", in collaboration with V. Lainey (l’Observatoire de Paris). For Efroimsky, this presentation was crucial for the extra reason that the "anonymous" reviewer of a paper, on which the talk was partially based, was sitting in the audience. After the talk, the anonymous reviewer openly expressed his approval of the work.
Murison spent much of the first half of the conference (in the early morning before sessions and late at night after sessions) helping the conference hosts and DDA Officers deal with various meeting-related issues. Murison is the recently re-elected DDA Secretary, so he also took the official minutes of, gave reports to, and participated in policy and decision-making discussions at the DDA Committee and Business meetings. These meetings took place Sunday before the start of the general meeting and Monday after the conclusion of that day's scientific sessions. Murison also served as the DDA's photographer for the conference (with help from Alice Monet (Flagstaff)).
Of the numerous reports and talks presented at the meeting, many were well above the run of the mill. This made for a very (in fact unusually) profitable meeting, from a dynamical perspective.
Many of the contributed papers of colleagues led Murison to think of several new and worthwhile research projects. Here are just a few:
- Dan Scheeres's (U. Michigan) talk on the effects of solar radiation on the rotational dynamics of asteroids raised the question in Murison's mind of what happens as the asteroid spin rate approaches zero. The dynamics is likely chaotic, especially as resonances (which were touched upon by Alan Harris in his talk on binary asteroids) are traversed.
- Kevin Walsh (U. Maryland, also one of the Student Stipend awardees) presented results of a model of NEA binary formation via tidal disruption. This led Murison to wonder if migration of binary asteroids from the main belt (mostly via secular resonances) is different in character from the single asteroids due to the slightly different perturbations experienced by the former.
- Wayne Hayes (Irvine) gave a talk whose main point is that it appears that whether or not the outer solar system is seen to be chaotic in numerical simulations is buried inside the current observational uncertainty. This indicates to Murison that the dynamical phase space has fine-scale structure (this should not come as a surprise to researchers in chaotic dynamics) and would be a rich research avenue.
- Mark Showalter (SETI) talked of the outer rings and chaotic orbits within the Uranian system as observed by HST. It turns out that the small moons Cupid and Belinda are not in 1:1 resonance even though they share very nearly the same semimajor axis. Murison would like to investigate the evolutionary history of these satellites (past and future) as well as determine if high-order resonances might play an important role.
- Matt Tiscareno (Cornell) talked of the density wave response of Saturn's rings to inner Lindblad resonances with the co-orbital satellites Janus and Epimetheus, based on Cassini observations. These two satellites are in mutual horseshoe orbits, swapping places every four years. This begs the question: How stable is this configuration to the many perturbations present in the Saturnian system? Since the mass ratio of the satellites is ~4, it might be an important factor. (In such studies the satellite masses are often assumed to be infinitesimally small.)
- It is by now well-known that the outer solar system planets migrated significantly due to scattering of planetesimals. If Jupiter (and/or the other gas giants) had already collected contingents of Trojans, then the question arises: What happens to such objects as they pass through low-order mean-motion resonances as they are dragged along with their primaries? Murison is not sure which talk sparked this question — probably either Matija Cuk's (British Columbia) paper on putative Lunar Trojans or Paul Weigert's (Western Ontario) talk on quasi-satellites (see below).
- Toshio Fukushima (NAOJ), a frequent visitor to USNO, talked of using the Levi-Civita coordinate transform in a particular perturbed two-body problem. Regularization of the two-body problem usually makes use in one way or another of the L-C spatial transform and the Sundman time transform. Murison was prompted by this talk to wonder if the Sundman transform can be employed in solving (both numerically and analytically) the Kepler equation. This is particularly fortuitous timing as Murison is currently working on an optimal numerical method for solving the KE as a result of his work that he presented at this conference.
- Man Hoi Lee (Santa Barbara) discussed his recent analytical work on the orbits and masses of the newly-discovered satellites of Pluto, S/2005 P1 and S/2005 P2. It would be very interesting to explore numerically the dynamics and stability of the Pluto system as we now know it, since the mass ratio of Pluto & Charon is (and hence their perturbative influences are) so very large.
Geoff Marcy (Berkeley) in his invited talk confirmed the statement made earlier by Butler, that most of the extrasolar planets follow elongated orbits. This is one of the mysteries of the planetary astronomy. Marcy clarified that the closer to the star the less high-eccentricity orbiters. This by itself is not surprising, because at close distances the orbits may have been circularized by tidal forces. The question remains how the planets initially acquire their large eccentricities. Dimitri Veras of the U of Colorado reviewed in his talk a couple of possible mechanisms. Both mechanisms emerge in pretty crowded many-body systems. No mechanism applicable to a single planet has been suggested so far. Motivated by the afore quoted talks by Marcy and Veras, Michael Efroimsky is currently developing such a mechanism.
Jim Williams of JPL, in his Brouwer Award lecture (2.4 MB PDF), provided a comprehensive review of the Lunar ranging. Among many other things, he raised the old issue of the dependence of the Lunar attenuation quality factor Q upon the tidal frequency f. In their earlier publication dated by 2001, Williams and his team reported that Q was proportional to f taken to the power of -0.19 (the 'minus' sign acting as a red flag for solid-state physicist). At this meeting, though, Williams was already talking about -0.07, an optimistic trend in Efroimsky's view. Efroimsky hopes that in another five years their team will transcend zero and will eventually report a positive factor, so that the Lunar seismology gets happily reconciled with the condensed-matter physics, and we all take a long breath. Williams's talk was a first for the DDA: since Jim does not travel, he gave his lecture remotely via telephone. This talk and the subsequent discussion, at the Meeting and then via e-mail seems to have given start to a new collaboration. Williams and Efroimsky came to an agreement that the Lunar-Ranging Team had almost certainly misinterpreted the data on attenuation in the Moon (and, possibly, in the Earth). We are now thinking of how to amend this issue.
Another excellent invited talk was given by Steven Majewski (Virginia), on Galactic structure and tidal stream dynamics. Murison had no idea so many (twenty-something!) different streams have been observationally identified, most of them in just the past few years. Interestingly, the coherence of the streams — a result of their dynamical "coldness" — enables them to be used as surprisingly sensitive probes of the Galactic potential and hence place significant constraints on cold dark matter models and models of structural evolution. Our Galaxy's environs are shockingly violent (if a bit slow on human timescales). Majewski highlighted a serious need for high-precision proper motions attainable only from space astrometry missions such as SIM.
Paul Weigert (Western Ontario) gave in his invited talk an overview of the fascinating dynamics of the so-called quasi-satellites discovered in recent years as well as horseshoes and tadpoles. His graphical and animated illustrations were particularly effective. These kinds of orbits are of particular interest to Murison since he did his dissertation research on the restricted three-body problem, in which these orbits play a central role in the overall dynamical picture of the problem. There is still much work to be done on the stability of these orbits, especially in the solar system context.
This was pretty much our weather most of the week.
Group shot of meeting participants.
Ready for lobster slaughter! L. to R.: Alice Monet (USNO Flagstaff), Pete Shelus
(U. Texas), Mike A'Hearn (U. Maryland), Bill Jefferys (U. Texas).
Marc & Michael atop a 93 year old research vessel docked at the Maritime
Museum.
A billboard you're not likely to see in the U.S.
Despite the dismal weather, residents of Halifax are not without a good sense of
humor
Lights across the harbor of Halifax's sister city, Dartmouth.
Legion of Little Helpers in the Gut Keeps Us Alive
from WaPo:
By Rick Weiss
So you think you are the self-reliant type.
A rugged individualist.
Well, give it up. You’d be nothing without the trillions of microbial minions toiling in your large intestine, performing crucial physiological functions that your highfalutin human cells wouldn’t have a clue how to do.
That’s one of the humbling truths emerging from the most thorough census yet of the bacterial tenants homesteading in our bodies. The new view, made possible by cutting-edge DNA screening methods, shows that the vaunted human genome—all the genes in our cells—is but a fraction of what it takes to make a human.
In fact, it’s time to stop thinking of yourself as a single living thing at all, say the scientists behind the new work. Better to see yourself as a “super-organism,” they say: a hybrid creature consisting of about 10 percent human cells and 90 percent bacterial cells.
“The numbers might strike fear into people, but the overall concept is one we have to understand and adjust to,” said Steven Gill, a microbial geneticist who helped lead the study at the Institute for Genomic Research in Rockville.
A better understanding of the bacteria colonizing our bodies could have far-reaching medical implications. In the not-too-distant future, Gill and others predicted, doctors will test for subtle changes in the numbers and kinds of microbes in people’s guts as early indicators of disease. Doctors may prescribe live bacterial supplements to bring certain physiological measures back into normal range. And drug companies will invent compounds that mimic or amplify the actions of helpful bacteria.
“These microbes are master physiological chemists,” said Jeffrey I. Gordon of Washington University in St. Louis, another team member. “Understanding their biosynthetic capabilities and following the pathways by which they operate could be the starting point for a 21st-century pharmacopoeia.”
Scientists have long recognized that the number of human cells in the body is dwarfed by the 100 trillion or so bacteria living in and on it. It’s a daunting reality obscured by the fact that human cells are much bigger than bacterial cells. For all their numbers, bacteria account for only about three pounds of the average person’s weight.
Just how important those three pounds are, however, has been difficult to appreciate until now. Most bacteria are too finicky to grow in laboratory dishes. As a result, little was known about who these majority shareholders really are and what, exactly, they are doing to and for us.
The new study, described in last week’s issue of the journal Science, took a novel approach. Rather than struggling to grow the body’s myriad microbes and testing their ability to perform various biochemical reactions—the methods scientists traditionally use to classify bacteria—the team used tiny molecular probes resembling DNA Velcro to retrieve tens of thousands of snippets of bacterial DNA from smidgeons of the intestinal output of two volunteers.
By comparing the DNA sequences of those snippets with those of previously studied bacteria, the team was able to sort many of the invisible bugs into known families.
Hundreds of others, it became clear, belong to microbial families unknown to science until now.
But the team members went further. By comparing the genetic puzzle pieces with similar sequences stored in databases, they were able to determine what biological functions many of these microbes are performing in the gut. And, as it turns out, no small number of those functions are crucial to human survival.
Some of the bacteria have the genetic machinery to make essential vitamins that are not found in the diet and that human cells can barely manufacture, including several B vitamins. Others make enzymes that can break the chemical bonds in plant fibers, or polysaccharides, where a plant’s nutritional energy is stored.
“We have very few of those linkage-busting enzymes encoded in our own genome, but these microbial genomes have a whole arsenal of gene products to degrade plant polysaccharides to energy,” Gordon said.
Some bacteria in the gut break down flavonoids and other chemicals made by plants that could cause cancer or other illnesses if they were not neutralized in the intestines.
Others have the genetic capacity to scavenge hydrogen gas from the gut—a byproduct of digestion that can kill helpful bacteria—and convert it into methane. That makes the intestines a more biologically friendly place, while contributing in sometimes embarrassing moments to Earth’s accumulation of greenhouse gases.
And in one especially touching example, bacteria in the gut make generous quantities of an enzyme that facilitates the production of butyryl coenzyme A, a fatty acid that is a favorite food of the cells that line the colon.
“We provide them a great place to live,” study author David A. Relman of Stanford University said of the bacterial cells, “and they are feeding the lining of our gut.”
The new work does not purport to be a complete survey of all microbes in the human gut. And it did not even take a stab at the body’s other pockets of microbial diversity—primarily the nose and mouth, the vagina, and the skin. But it demonstrates that the DNA-based approach has the potential to reveal at last the metabolic details of our many mini-mes, said Claire M. Fraser-Liggett, president and director of the Institute for Genomic Research.
With the technology improving and getting cheaper, she said, it won’t be long before it is easy to monitor a person’s microbial changes from day to day—or compare bacterial population structures among individuals who have different diets or health histories.
“One question we need to tackle is: Is there such a thing as a core microbiome, a set of organisms or bacterial genes you find in most or all individuals?” Fraser-Liggett said. “It may be that microbes are very stable and diet doesn’t play a huge role. Or it may be that this is a snapshot in time reflecting something they ate in their last meal.”
With that kind of information in hand, doctors could think about prescribing particular “probiotic” foods or supplements to change a patient’s microbiome in healthful ways, or adjusting a patient’s diet to make a better fit with the bugs that the patient is saddled with.
“To ignore our microbial side would be to ignore an important contributor to our health and our biology,” Gordon said.
Edward DeLong, a professor at the Massachusetts Institute of Technology who has used similar techniques to study marine microbial diversity, said he was not completely comfortable with the idea that people are super-organisms. “I’m not sure where the super-organism ends and the environment begins,” he said.
But he said he appreciated the focus on the positive side of bacteria.
“We typically think of microbes as being associated with human disease,” DeLong said. “But they are always with us and are associated most of the time with human health.”
NASA’s Shameful Reverse Thrust
Another one from the category of Duh.
from SciAm:
When George W. Bush unveiled his plan for a new moon shot two years ago, a lot of people worried that it was long on rhetoric and short on cash--ultimately forcing NASA to raid its science budget to pay for it. On close examination, though, the trajectory seemed reasonable. The money freed up by phasing out the space shuttle and the International Space Station was not an implausible amount to build a post-shuttle spacecraft (known as the Crew Exploration Vehicle, or CEV) and send it moonward by 2020. A “go as you can pay” strategy would extend the deadlines if money got tight, rather than pickpocketing other programs. A modest dollop of extra funds would help cover the transitional costs. NASA administrator Michael Griffin said at a press conference last September: “In our forward planning, we do not take one thin dime out of the science program in order to execute this architecture.”
Now it looks like the skeptics were right. The NASA budget announced in February mows down a scarily long list of science missions, from a Europa orbiter to a space-based gravitational-wave observatory. Research grants to individual scientists, traditionally kept safe from high-level budget machinations, have taken a 15 percent hit, retroactive to last fall; hundreds have already received “termination letters” canceling their projects. Griffin went before Congress in February as the bearer of bad news: “Fulfilling our commitments on the International Space Station and bringing the Crew Exploration Vehicle online in a timely manner, not later than 2014 and possibly much sooner, is a higher priority than these science missions during this period.” [Thus confirming that Griffin is a sack of shit.]
The countdown to the crisis actually began a year ago, when the Bush administration lopped off the dollop of bridging funds it had promised. Then came Hurricane Katrina, which damaged shuttle facilities in Mississippi and Louisiana, and an across-the-board federal budget cut, largely to raise money for the Iraq War. Worst of all, a new analysis of the shuttle and space station found them at least $2 billion in the hole. Griffin went cap in hand to the administration but was told to make up the difference from the agency’s own wherewithal. [Was anybody surprised?]
Compared with the plan of two years ago, science gives up a total of $6.4 billion (in 2005 dollars) over the five years from 2007 through 2011—a 20 percent cut. Planetary exploration is the worsthit area—40 percent. Human spaceflight gains $5.2 billion, but its situation is hardly to be envied either. The shuttle fleet will make 16 rather than 28 trips to the space station before retiring in 2010, and from then until the CEV debuts, the country will have no capability to launch astronauts into orbit at all.
Griffin has described the shift of money as a “speed bump,” a temporary measure to get human spaceflight back on course. Veteran observers express sympathy for his dilemma. “It’s a knotty problem,” says John M. Logsdon, director of the Space Policy Institute at George Washington University. “There’s no clear answer.”
Nevertheless, many complain that he has been heavy-handed [and a fool]. Multiyear projects require some consistency in their funding. By making such an abrupt budget change, NASA will mothball or abandon half-built (in some cases, fully built) hardware, lose expertise developed at great effort [and expense], and leave gaps in data coverage, notably of the earth’s climate. NASA has had budget crunches before, but seldom have they been so wasteful.
“It’s the sudden change in slope: that’s why this is more difficult than it was in previous years,” says Lennard Fisk, chair of the National Research Council’s Space Studies Board and himself a former NASA official. The unprecedented targeting of research grants strikes scientists as particularly gratuitous: for a small savings, only about $80 million, NASA is causing a huge disruption.
The Space Studies Board is investigating how to hold on to the grants and smaller missions by delaying or downgrading the bigger fry. Several flagship missions, such as the James Webb Space Telescope, have run over budget and need housecleaning anyway. Wesley Huntress, director of the Geophysical Laboratory of the Carnegie Institution of Washington and another past NASA official, says scientists need to take responsibility for making the necessary trade-offs, rather than leaving it up to NASA headquarters and Capitol Hill. [Translation: Bush has unalterably screwed NASA and American space science, so good luck with that.]
Some hope the crisis may finally force some out-of-the-capsule thinking. Should NASA jettison the shuttle and station right away? Should it do the opposite and stretch out the station’s construction to reduce its annual cost? Should NASA be split into separate science and astronautics agencies? If it were, would that really be good for science? Unless some helpful reform can be salvaged from the situation, what seemed [only to idiots] like such a grand vision two years ago may fail in the execution.
Science Under Attack
From Nature (23 Feb., 2006):
Researchers are increasingly upset with the Bush administration, not for its tactics but for its entire operational philosophy.
The highlight of the annual meeting of the American Association for the Advancement of Science (AAAS) last week was an impassioned session in which scientific leaders, including molecular biologist David Baltimore, made clear their views on the fraught relationship between science and the Bush administration.
The discussion was organized by the Union of Concerned Scientists in the wake of revelations about how the administration’s political appointees have sought to control the messages communicated by scientists to the public, including attempts by the NASA press office to muzzle climate scientist James Hansen (see page 896).
And judging from the response at a packed and emotional hall in St Louis, a great many US scientists now believe that the Bush administration is prepared not only to ignore scientific facts in making policy decisions, but also to suppress findings that conflict with its own priorities.
For Baltimore — Nobel laureate, outgoing president of the California Institute of Technology, president-elect of the AAAS, and arguably the most eminent voice in all of American science — events have reached a tipping point. He suggested that the Bush administration’s approach to science stems from its adherence to a particular philosophy of government, that of a ‘unitary executive’. Instead of resignedly shrugging their shoulders whenever such a case of scientific manipulation arises, Baltimore argued, scientists need to recognize the potency of the threat that this governmental philosophy represents to the long-cherished independence of US science.
The unitary executive is an old idea, but not many Americans had heard of it until last month, when it cropped up during the Senate confirmation process of Supreme Court judge Samuel Alito. At the extreme, it holds that the executive branch can run the US federal government as it sees fit, especially in wartime. Given that a seminal achievement of the Constitution of the United States was to establish a balance of power between the executive branch, the Congress and the judiciary, this may sound absurd, but it seems to hold considerable sway within the Bush administration.
Baltimore warned that the doctrine opens the way for “an exertion of executive hegemony over science”. He called on researchers to “fight for a very different doctrine” under which “the executive’s role is to defend intellectual freedom”. In the light of the Bush administration’s adherence to this philosophy, he added: “It is no accident that we are seeing such an extensive suppression of science.” From someone of Baltimore’s experience and reputation, these are strong words.
For science to flourish it needs settings that support freedom of enquiry, and the creation of such settings was a great achievement of the Enlightenment. Protecting them is vital, not just for science but for all of humanity.
Government agencies can never provide such settings in quite the same way universities can. But their scientists must still be allowed to express the results of their research as they see fit. They should also be free to discuss how their research makes an argument for changes in policy, as Hansen sought to do with regard to climate change. In return, scientists have to acknowledge that the line between science and policy is a fine one, and endeavour to distinguish clearly between their scientific findings and their policy ideas.
In its five years in office, the Bush administration has sought to exert tighter control of the branches of government where scientists work. This applies not only to regulatory agencies, where politics are never far below the surface, but also to places such as the National Institutes of Health and NASA, where intramural researchers are used to the freedom of expression enjoyed by their university colleagues.
It is by no means the case that these proud federal agencies or their staff have fallen subject to the executive branch’s decree. Most federal agencies have a deep stock of integrity, which even eight years of the Bush administration will not erode away. Yet Congress, in particular, should be doing much more to defend them from White House interference. And researchers should stand up and be counted with colleagues in the federal government in their hour of need.
3C 75 in Abell 400: Gravitationally Bound Black Holes
From the Chandra X-Ray Observatory:
This composite X-ray (blue)/radio (pink) image of the galaxy cluster Abell 400 shows radio jets immersed in a vast cloud of multimillion degree X-ray emitting gas that pervades the cluster. The jets emanate from the vicinity of two supermassive black holes (bright spots in the image). These black holes are in the dumbbell galaxy NGC 1128, which has produced the giant radio source, 3C 75.
Liquid Crystal Bifocals
from SciAm:
Eyes lose their flexibility with age, sometimes making it difficult to shift focus from near to far or vice versa. To combat the problem, Benjamin Franklin devised bifocals--eyeglass lenses shaped for near viewing in the lower half and distance vision in the upper portion--more than 200 years ago. Now researchers have created liquid crystal lenses that can change between long-distance and reading modes with the flick of a switch.
Guoqiang Li of the University of Arizona and his colleagues sandwiched a thin layer of liquid crystal between two layers of glass and laced it with concentric rings of electrodes. When turned on, the electrodes reconfigure the focusing power of the lens for either near or far vision, allowing the entire lens to promote the desired effect in less than a second.
In tests on both human and mechanical subjects, the liquid crystal lens delivered a sharp image whether focusing on the close at hand or the distant. And in an improvement on earlier efforts with liquid crystals, if the electrical current fails for any reason, the lens simply reverts to its distance-viewing state. Because most people requiring bifocals have difficulty seeing up close rather than far away, this feature makes the glasses safe for activities like driving, the scientists argue. The research appears online this week in Proceedings of the National Academies of Science.
Balloon Data Confirms Antarctic Warming Trend
from SciAm:
Launching weather balloons has been a nearly daily habit at some Antarctic research facilities since 1957. Carrying radiosondes--instruments that measure atmospheric conditions such as temperature and wind speed--the balloons travel as high as 12 miles or more. A new analysis of the past 30 years of records from nine research stations, including Amundsen-Scott at the South Pole, reveals that the air above the entirety of Antarctica has warmed by as much as 0.70 degree Celsius per decade during the winter months.
John Turner of the British Antarctic Survey and his colleagues report in today’s issue of Science that this warming trend is consistent across data from multiple stations run by multiple countries using multiple types of instruments. Previous studies had shown that Antarctica’s surface temperatures had warmed by roughly 2.5 degrees C over the last half century, but this study provides the most complete look at atmospheric trends to date.
“The rapid surface warming of the Antarctic Peninsula and the enhanced global warming signal over the whole continent shows the complexity of climate change,” Turner says. “Greenhouse gases could be having a bigger impact in Antarctica than across the rest of the world and we don’t understand why.”
This warming has implications for snowfall on the continent as well as the melting of land-based ice reserves, potentially leading to global sea-level rise, the researchers warn. Although they cannot ascribe a particular cause to the warming, they ruled out several other potential explanations, including heat transfer from other regions (there was no observed change in wind patterns) and solar radiation changes (the sun is either at or below the horizon throughout the winter months in question).
And although current computer models fail to predict this warming trend, the scientists argue that the data is consistent with what would be expected as a result of increasing greenhouse gases. “Our next step,” Turner says, “is to try to improve the models.”
A magnetic torsional wave near the Galactic Centre traced by a ‘double helix’ nebula
from a paper in Nature:
Mark Morris, Keven Uchida and Tuan Do
Abstract
The magnetic field in the central few hundred parsecs of the Milky Way has a dipolar geometry and is substantially stronger than elsewhere in the Galaxy, with estimates ranging up to a milligauss. Characterization of the magnetic field at the Galactic Centre is important because it can affect the orbits of molecular clouds by exerting a drag on them, inhibit star formation, and could guide a wind of hot gas or cosmic rays away from the central region. Here we report observations of an infrared nebula having the morphology of an intertwined double helix about 100 parsecs from the Galaxy’s dynamical centre, with its axis oriented perpendicular to the Galactic plane. The observed segment is about 25 parsecs in length, and contains about 1.25 full turns of each of the two continuous, helically wound strands. We interpret this feature as a torsional Alfvén wave propagating vertically away from the Galactic disk, driven by rotation of the magnetized circumnuclear gas disk. The direct connection between the circumnuclear disk and the double helix is ambiguous, but the images show a possible meandering channel that warrants further investigation.
Chinese Torrent Frogs Share Bats’ Ultrasonic Capabilities
from WaPo:
Not only can a rare Chinese frog sing like a bird, it can also apparently hear like a bat, according to new research.
Albert S. Feng of the University of Illinois at Urbana-Champaign and colleagues previously reported that male torrent frogs that live in an area west of Shanghai produced calls that were remarkably similar to bird songs.
In a new study, published in Thursday’s issue of Nature, Feng and his colleagues determined that the creatures also communicate with one another through high-frequency ultrasonic calls, which previously only bats, marine mammals and some rodents were known to use.
Feng and his colleagues recorded the frogs’ audible and ultrasonic calls and then studied how eight other males responded to them, finding that most of them responded to calls in both the audible and ultrasonic ranges.
Feng and his colleagues speculated the frogs evolved the ability so they could hear each other above the sound of waterfalls and other noise in their mountainous habitat.
“Nature has a way of evolving mechanisms to facilitate communication in very adverse situations,” Feng said. “One of the ways is to shift the frequencies beyond the spectrum of the background noise. Mammals such as bats, whales and dolphins do this and use ultrasound for their sonar system and communication. Frogs were never taken into consideration for being able to do this.”