Май 2002 г.

Российская наука и мир (по материалам зарубежной электронной прессы)

CONTENTS / ОГЛАВЛЕНИЕ


• Heart of Science Still Beats in Siberia
• Scientists Wary of New Academy Reforms
• U.S. companies say investment in Russian information technology pays back
• Enemy of the State
• Washington State U. prof to visit Siberia with group
• Albany Molecular Research, Inc. Strengthens Scientific and Management Team
• Rock Till You Drop
• Scientists to discuss Lake Vostok research at webcast press conference
• Water, Water Everywhere on Mars, Scientists Find
• Odyssey data hints at icy Mars oceans
• Maps of Subsurface Hydrogen from the High-Energy Neutron Detector, Mars Odyssey

Three nations agree to share ice core that may yield clues about nature of Lake Vostok

Ученые из США, Франции и России поделят между собой глыбу льда, взятую с поверхности озера Восток, с тем, чтобы выяснить тайну его происхождения

Scientists from the United States, France and Russia will equally share samples of an 11.7-meter (38.5-foot) ice core taken from the ice sheet above Lake Vostok, deep in the Antarctic interior, under the terms of an agreement worked out among representatives of the nations' Antarctic research programs.
Glaciologists, geochemists and biologists will use the lower portions of the Vostok ice core, which was drilled in 1998, to learn more about the subglacial lake known to exist under the ice at Russia's Vostok Station, high on the polar plateau. Joint investigative protocols will allow scientists to explore some intriguing questions about the lake while insuring the compatibility and consistency of individual investigations. Major questions that will provide the framework for future research on the ice core include: How is the ice formed and what is its age? What does the geochemistry of the ice reveal about the lake and its origin? What kinds of organisms are present in the lake and how did they get there?
The agreement was reached at a meeting of U.S., French and Russian scientists held in April at the National Science Foundation (NSF) headquarters in Arlington, Va. Participants included the directors of the U.S., French and Russian Antarctic programs as well as scientists and program managers who support or conduct research on the Vostok ice core. NSF funds and manages the U.S. Antarctic Program, which supports almost all U.S. research on the continent and in surrounding waters.
The ice samples were drilled at Vostok Station under the terms of a U.S., French and Russian scientific collaboration that has made important contributions to the understanding the last 420,000 years of the Earth's climate. Research on these samples has delivered valuable insights for understanding the forces that drive climate change.
The samples governed by the agreement were left at Vostok Station until the 2001-2002 austral summer, when arrangements were made to bring out some of the remaining ice from a storage trench. They represent roughly the bottom 12 meters of the ice core and are thought to have formed from accretion, the process by which water from the lake freezes onto the base of the ice sheet. This ice is different from the core that provided the Vostok climate record. A plan developed at the NSF meeting will allow the three nations to cooperate and share the samples in such a way as to maximize the scientific return and ensure an accurate comparison of results.
Most notably, participants devised a plan to use a piece of the accretion ice for comparative study of ice-decontamination methods for biological studies. This procedure will ensure that research results obtained in different laboratories can be compared without undue concern about sample contamination.
Existing collaborations between French and Russians scientists and among U.S. scientists will continue and will allow analyses of the shared core to begin in the very near future.
Scientists from the U.S., France, and Russia will continue to examine the ice after a review of research proposals submitted to the nations' Antarctic programs. Plans for a future subglacial lake exploration and research are scheduled for discussion at an upcoming meeting in Shanghai, China in July. A four-person panel of researchers from the U.S., France and Russia is scheduled to discuss recent research conducted at Lake Vostok during a press conference at 3 p.m. EDT on May 28 as part of the spring meeting of the American Geophysical Union in Washington D.C.

Огромное море льда лежит под поверхностью Марса. Будущие исследователи смогут использовать его как источник топлива и, возможно, даже в качестве питьевой воды

WASHINGTON (Reuters) - A huge sea of ice lies just under the surface of Mars, ready to be tapped by future explorers as a source of fuel and maybe even drinking water, scientists said Monday. It might also harbor life, and certainly explains where all the water went when Mars went from being a warm and wet place to the cold, dry desert it is now, the researchers report in this week's issue of the journal Science. "It turns out it is really quite a bit more ice than I think most people ever really expected," William Boynton of the University of Arizona in Tucson, who led one of the studies being published this week, said in a telephone interview.
"What we are seeing is there is a layer of ice just a little beneath the surface. It is maybe a meter (three feet) beneath the surface."
For the past few years, scientists studying Mars have been looking for water for a number of reasons. For one, life as we know it requires water, and anyone who wants to spend any time on the planet will need water to drink and to use as a source of hydrogen for fuel.
It certainly looks like Mars once had water on the surface -- lots of it. There are deep canyons, one deeper and wider than anything on Earth, and places that look like dried-up lake or seabeds.
The surface is now dry and dusty and the ice that covers the poles is frozen carbon dioxide, not water. But NASA has pointed a range of instruments at the planet to try and see if water is there and if so, if it is easy to get at.
Evidence has been seen in photographs of seeping water, and the orbiting Odyssey spacecraft was directed to look for chemical evidence of water, which should be recognizable because of its high hydrogen content.
Hydrogen quickly combines with other elements, so if it is found on a cold planet, it is very likely to have teamed up with oxygen to form water.

Gamma and Neutron Rays

NASA craft's discovery supports a theory that life existed there and may still

NASA's Mars Odyssey spacecraft has discovered what appear to be the frozen remains of vast oceans on Mars, scientists report this week. The finding lends support to theories that early in its history Mars was wet and warm, and possibly amenable to life. It could simplify a human mission to Mars, supplying a source of drinking water and fuel for a return. Scientists who study the surface of Mars, arid and frigid, have long wondered: Where did all the water go?
The answer appears to be down, and not very far. In the polar regions, the surface is covered by a foot or two of dry soil. Below that, pores in the soil and rocky debris appear to be encrusted with ice. The concentration of ice is surprisingly high at one-fifth to one-third by weight and up to 60 percent by volume, the scientists report. In the equatorial regions, there was little water near the surface.
The journal Science will publish three scientific papers on the Odyssey measurements Thursday on its Web site, and some details were reported in the British media over the weekend. The lead authors of the three papers are William V. Boynton of the University of Arizona's Lunar and Planetary Laboratory, William C. Feldman of Los Alamos National Laboratory and Igor G. Mitrofanov of the Institute for Space Research in Moscow.
"The results, even after only a month of mapping observations, are stunning," Dr. James F. Bell, a professor of astronomy at Cornell University, writes in an accompanying commentary, which will appear on Science's Web site.
Launched in April last year, the Odyssey arrived at Mars in September. After slowly nudging itself into its final orbit about 200 miles above the surface, the spacecraft began in February its $300 million mission of mapping the distribution and concentration of chemical elements and minerals on the planet's surface.
A month later, scientists announced they had detected strong signs of subsurface ice. The new papers provide the details and analysis of the initial observations.
The presence of large amounts of ice could reduce the amount of water that needed to be carried along if NASA were to plan a human mission to Mars. Moreover, the water could be broken down into hydrogen and oxygen to fuel the return trip.
Scientists find evidence of water from the huge canyons, far larger than anything on Earth, carved in Mars' surface and in features that resemble ancient coastlines. Some believe a third of the planet, most of its northern hemisphere, was once covered by water, which conjures up speculation that Martian sealife arose billions of years ago. Water and warmth are considered the two essential ingredients for life.
There is little water on the surface today. The planet's northern ice cap is about 750 miles wide and contains about 300,000 cubic miles of ice. Antarctica, by contrast, is covered by 7 million cubic miles of ice. Thus, scientists who believed the picture of a wet, possibly life-filled early Mars needed to explain where the water had gone. Some could have evaporated into space. For the rest, they looked beneath the surface. The spacecraft's instruments cannot directly detect water. Rather, they have picked up signs of hydrogen based on neutrons coming from the Martian surface.
Neutrons, particles found in the nuclei of atoms, are continually knocked off the surface by cosmic rays, but these neutrons fly out at very high velocities.
When the high-velocity neutrons run into hydrogen atoms, which are almost the same mass, the neutrons lose much of their momentum, like a cue ball coming almost to a halt after hitting another billiard ball.
Thus, when Mars Odyssey passes over a region containing hydrogen, it sees more slow neutrons and fewer of the faster ones. That data signature is unique to hydrogen.
The signs of hydrogen are strongest around Mars' south pole, particularly below 60 degrees latitude. The most plausible explanation for the presence of hydrogen near the surface is that it is tied up in water molecules. The instrument is similar to the one on the Lunar Prospector spacecraft that detected signs of ice in the deep craters near the moon's poles in 1998. The measurements can detect hydrogen only about a yard below the surface. However, it is believed the layer of rock and dust is porous enough to contain enough water for a planet-wide ocean between one-third and one mile deep.
"The subsurface ice detected by Odyssey," Bell wrote, "may represent only the tip of an iceberg frozen underground." Vast amounts of liquid water on early Mars not only raises hope that life evolved there, but also that it could still survive today. The survivors, microbes at best, would have had to migrate deep into the interior regions that are warmed by the planet's core.
To discover if life exists would require going to Mars and digging beneath the iceberg.

Abstract

After 55 days of mapping by the High-Energy Neutron Detector onboard Mars Odyssey, we found deficits of high energy neutrons in southern highlands and the northern lowlands of Mars. The deficits of high energy neutrons indicates that hydrogen is concentrated in the subsurface. Modeling suggests that water-ice rich layers that are tens of centimeters in thickness provide one possible fit to the data.

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