His Finalist Year: 2006 [More]
His Finalist Year: 2006 [More]
The “earth” part of the title of this special issue from Scientific American is no doubt self-explanatory, but why “3.0”? Because this planet is no longer simply the home of our species: it is also our creation. And as with any product, sometimes it is prudent to upgrade its quality.
If you will indulge the analogy further, Earth 1.0 was the world that persisted and evolved for billions of years, up until very recently. The environment was dominated by closed ecological loops and a few geological and astronomical processes, such as the movements of continents and the brightness of the sun. As such, life was highly sustainable. Even after we humans developed agriculture, which considerably enlarged our footprint on the environment, our overall influence was fairly small and localized.
[More]The “earth” part of the title of this special issue from Scientific American is no doubt self-explanatory, but why “3.0”? Because this planet is no longer simply the home of our species: it is also our creation. And as with any product, sometimes it is prudent to upgrade its quality.
If you will indulge the analogy further, Earth 1.0 was the world that persisted and evolved for billions of years, up until very recently. The environment was dominated by closed ecological loops and a few geological and astronomical processes, such as the movements of continents and the brightness of the sun. As such, life was highly sustainable. Even after we humans developed agriculture, which considerably enlarged our footprint on the environment, our overall influence was fairly small and localized.
[More]Editor's Note: This story was originally printed in the February 2004 issue of Scientific American. We are reposting this story because author Adam Riess was selected as a MacArthur Fellow in 2008 by the MacArthur Foundation.
From the time of Isaac Newton to the late 1990s, the defining feature of gravity was its attractive nature. Gravity keeps us grounded. It slows the ascent of baseballs and holds the moon in orbit around the earth. Gravity prevents our solar system from flying apart and binds together enormous clusters of galaxies. Although Einstein’s general theory of relativity allows for gravity to push as well as pull, most physicists regarded this as a purely theoretical possibility, irrelevant to the universe today. Until recently, astronomers fully expected to see gravity slowing down the expansion of the cosmos.
[More]Editor's Note: This story was originally printed in the February 2004 issue of Scientific American. We are reposting this story because author Adam Riess was selected as a MacArthur Fellow in 2008 by the MacArthur Foundation.
From the time of Isaac Newton to the late 1990s, the defining feature of gravity was its attractive nature. Gravity keeps us grounded. It slows the ascent of baseballs and holds the moon in orbit around the earth. Gravity prevents our solar system from flying apart and binds together enormous clusters of galaxies. Although Einstein’s general theory of relativity allows for gravity to push as well as pull, most physicists regarded this as a purely theoretical possibility, irrelevant to the universe today. Until recently, astronomers fully expected to see gravity slowing down the expansion of the cosmos.
[More][The following is an exact transcript of this podcast.]
[More][The following is an exact transcript of this podcast.]
[More]Note: This article, to be published in the October 2008 issue of Scientific American, was originally printed with the title, "Questions for Would-Be Presidents."Add your own questions for McCain and Obama in our comments section below.
[More]Note: This article, to be published in the October 2008 issue of Scientific American, was originally printed with the title, "Questions for Would-Be Presidents."Add your own questions for McCain and Obama in our comments section below.
[More]Not So Rapid Eye MovementThe bizarre metamorphosis that occurs in halibut and other flatfish had even Charles Darwin floundering for an explanation. At birth, these fish have one eye on each side of the skull, but as adults, both eyes reside on the same side. Certainly, for fish that spend their lives along the sea bottom, having both eyes topside confers a survival advantage. But there seemed to be no evolutionary reason to start down the gradual path toward such lopsidedness--any intermediate steps would not seem to be especially helpful. So some biologists theorized that the fish evolved from a single, sudden mutation.
[More]Not So Rapid Eye MovementThe bizarre metamorphosis that occurs in halibut and other flatfish had even Charles Darwin floundering for an explanation. At birth, these fish have one eye on each side of the skull, but as adults, both eyes reside on the same side. Certainly, for fish that spend their lives along the sea bottom, having both eyes topside confers a survival advantage. But there seemed to be no evolutionary reason to start down the gradual path toward such lopsidedness--any intermediate steps would not seem to be especially helpful. So some biologists theorized that the fish evolved from a single, sudden mutation.
[More][The following is an exact transcript of this podcast.]
[More][The following is an exact transcript of this podcast.]
[More]A new study of a stellar explosion visible from halfway across the universe finds that the blast had an unusual structure that researchers heretofore had never observed.
Gamma-ray burst GRB 080319B was already on record as the brightest stellar explosion ever recorded.
[More]A new study of a stellar explosion visible from halfway across the universe finds that the blast had an unusual structure that researchers heretofore had never observed.
Gamma-ray burst GRB 080319B was already on record as the brightest stellar explosion ever recorded.
[More]Bell Telephone Laboratories engineer Karl Guthe Jansky was only looking for ways to cut down on shortwave radio static when he found radio waves coming from outer space in 1932. Yet Jansky’s serendipitous discovery soon gave birth to radio astronomy, which has since delivered paradigm-shifting revelations ranging from the cosmic microwave background to the presence of dark matter in the universe. That science is now on the verge of a 21st-century renaissance that promises even greater discoveries, ushered in not by traditional huge radio dishes but by vast, powerful arrays of smaller dishes.
First developed by British radio astronomers in 1946, arrays make use of several radio telescopes spaced some distance apart, “synthesizing” a single telescope with an aperture equal to the spacing between the farthest elements. The most famous example, operating since 1980, is the Very Large Array (VLA) near Socorro, N.M., which has 27 active radio antennas mounted on railroad tracks in a Y configuration (another dish is kept as a spare). The instrument’s angular resolution is adjusted simply by moving the antennas closer together or farther apart. “The VLA has been and still remains the most powerful and flexible radio synthesis imaging telescope on earth,” says veteran VLA researcher Rick Perley. “But since that time there’s been enormous changes both in technology and in where science is headed.”
[More]Bell Telephone Laboratories engineer Karl Guthe Jansky was only looking for ways to cut down on shortwave radio static when he found radio waves coming from outer space in 1932. Yet Jansky’s serendipitous discovery soon gave birth to radio astronomy, which has since delivered paradigm-shifting revelations ranging from the cosmic microwave background to the presence of dark matter in the universe. That science is now on the verge of a 21st-century renaissance that promises even greater discoveries, ushered in not by traditional huge radio dishes but by vast, powerful arrays of smaller dishes.
First developed by British radio astronomers in 1946, arrays make use of several radio telescopes spaced some distance apart, “synthesizing” a single telescope with an aperture equal to the spacing between the farthest elements. The most famous example, operating since 1980, is the Very Large Array (VLA) near Socorro, N.M., which has 27 active radio antennas mounted on railroad tracks in a Y configuration (another dish is kept as a spare). The instrument’s angular resolution is adjusted simply by moving the antennas closer together or farther apart. “The VLA has been and still remains the most powerful and flexible radio synthesis imaging telescope on earth,” says veteran VLA researcher Rick Perley. “But since that time there’s been enormous changes both in technology and in where science is headed.”
[More]The detection of extra dimensions beyond the familiar four--the three dimensions of space and one of time--would be among the most earth-shattering discoveries in the history of physics. Now scientists at the Fermi National Accelerator Laboratory in Batavia, Ill., are designing a new experiment that would investigate tantalizing hints that extra dimensions may indeed exist.
Last year researchers involved in Fermilab’s MiniBooNE study, which detects elusive subatomic particles called neutrinos, announced that they had found a surprising anomaly. Neutrinos, which have no charge and very little mass, form out of nuclear reactions and particle decays. They come in three types, called flavors--electron, muon and tau--and oscillate wildly from one flavor to another as they travel along. While observing a beam of muon neutrinos generated by one of Fermilab’s particle accelerators, the MiniBooNE researchers found that an unexpectedly high number of the particles in the low-energy range (below 475 million electron volts) had transformed into electron neutrinos. After a year of analysis, the investigators have failed to come up with a conventional explanation for this so-called low-energy excess. The mystery has focused attention on an intriguing and very unconventional hypothesis: a fourth kind of neutrino may be bouncing in and out of extra dimensions.
[More]The detection of extra dimensions beyond the familiar four--the three dimensions of space and one of time--would be among the most earth-shattering discoveries in the history of physics. Now scientists at the Fermi National Accelerator Laboratory in Batavia, Ill., are designing a new experiment that would investigate tantalizing hints that extra dimensions may indeed exist.
Last year researchers involved in Fermilab’s MiniBooNE study, which detects elusive subatomic particles called neutrinos, announced that they had found a surprising anomaly. Neutrinos, which have no charge and very little mass, form out of nuclear reactions and particle decays. They come in three types, called flavors--electron, muon and tau--and oscillate wildly from one flavor to another as they travel along. While observing a beam of muon neutrinos generated by one of Fermilab’s particle accelerators, the MiniBooNE researchers found that an unexpectedly high number of the particles in the low-energy range (below 475 million electron volts) had transformed into electron neutrinos. After a year of analysis, the investigators have failed to come up with a conventional explanation for this so-called low-energy excess. The mystery has focused attention on an intriguing and very unconventional hypothesis: a fourth kind of neutrino may be bouncing in and out of extra dimensions.
[More]Humans, chimpanzees and dogs can live in a space environment for but a few minutes before the air in their lungs expands, gas bubbles out of their blood and the saliva in their mouths begin to boil. But more fundamental organisms such as bacteria and lichen can tolerate the absence of pressure and searing cold. And now researchers have found that animals known as tardigrades, or water bears, can, too. [More]
Humans, chimpanzees and dogs can live in a space environment for but a few minutes before the air in their lungs expands, gas bubbles out of their blood and the saliva in their mouths begin to boil. But more fundamental organisms such as bacteria and lichen can tolerate the absence of pressure and searing cold. And now researchers have found that animals known as tardigrades, or water bears, can, too. [More]
The future looks bright--maybe too bright. The sun is slowly expanding and brightening, and over the next few billion years it will eventually desiccate Earth, leaving it hot, brown and uninhabitable. About 7.6 billion years from now, the sun will reach its maximum size as a red giant: its surface will extend beyond Earth’s orbit today by 20 percent and will shine 3,000 times brighter. In its final stage, the sun will collapse into a white dwarf.
Although scientists agree on the sun’s future, they disagree about what will happen to Earth. Since 1924, when British mathematician James Jeans first considered Earth’s fate during the sun’s red giant phase, a bevy of scientists have reached oscillating conclusions. In some scenarios, our planet escapes vaporization; in the latest analyses, however, it does not.
[More]The future looks bright--maybe too bright. The sun is slowly expanding and brightening, and over the next few billion years it will eventually desiccate Earth, leaving it hot, brown and uninhabitable. About 7.6 billion years from now, the sun will reach its maximum size as a red giant: its surface will extend beyond Earth’s orbit today by 20 percent and will shine 3,000 times brighter. In its final stage, the sun will collapse into a white dwarf.
Although scientists agree on the sun’s future, they disagree about what will happen to Earth. Since 1924, when British mathematician James Jeans first considered Earth’s fate during the sun’s red giant phase, a bevy of scientists have reached oscillating conclusions. In some scenarios, our planet escapes vaporization; in the latest analyses, however, it does not.
[More]Researchers are closing in on ironclad evidence for the black hole believed to lurk at the center of our Milky Way galaxy. [More]
Researchers are closing in on ironclad evidence for the black hole believed to lurk at the center of our Milky Way galaxy. [More]
Leland Melvin has very nearly been a member of two exclusive clubs: the National Football League (NFL) and the NASA astronaut corps. The first opportunity fizzled before it got very far. The second, however, recently afforded him a roundtrip to the International Space Station (ISS).
The former NFL draft pick in February journeyed into orbit aboard the Space Shuttle Atlantis--an opportunity he had prepared for since beginning his training in 1998. The flight crew's goal: attach the European Space Agency's Columbus research laboratory to the ISS.
[More]Leland Melvin has very nearly been a member of two exclusive clubs: the National Football League (NFL) and the NASA astronaut corps. The first opportunity fizzled before it got very far. The second, however, recently afforded him a roundtrip to the International Space Station (ISS).
The former NFL draft pick in February journeyed into orbit aboard the Space Shuttle Atlantis--an opportunity he had prepared for since beginning his training in 1998. The flight crew's goal: attach the European Space Agency's Columbus research laboratory to the ISS.
[More]NewsHydrogen Power on the Cheap--Or, at Least, Cheaper [More]
NewsHydrogen Power on the Cheap--Or, at Least, Cheaper [More]
Planetary Protection RacketAs the first planet to form in our solar system, Jupiter helped to sculpt the rest [see “The Genesis of Planets”; SciAm, May 2008]. Because of its gravity, for instance, it has regulated the rate of cosmic impacts on Earth: flinging asteroids in our direction yet also clearing many hazardous space rocks out of our way. Jupiter’s net effect depends on its mass, suggest Jonathan Horner and Barrie Jones, both at the Open University in England, in an upcoming paper in the International Journal of Astrobiology. Had Jupiter one-fifth its mass, they calculate, it would have failed to clear asteroids out--and Earth might have been struck four times more often than it has been. But if Jupiter were still smaller, it would have flung fewer asteroids toward the inner solar system to begin with--and the dinosaurs might still be walking our planet. --George Musser
[More]Planetary Protection RacketAs the first planet to form in our solar system, Jupiter helped to sculpt the rest [see “The Genesis of Planets”; SciAm, May 2008]. Because of its gravity, for instance, it has regulated the rate of cosmic impacts on Earth: flinging asteroids in our direction yet also clearing many hazardous space rocks out of our way. Jupiter’s net effect depends on its mass, suggest Jonathan Horner and Barrie Jones, both at the Open University in England, in an upcoming paper in the International Journal of Astrobiology. Had Jupiter one-fifth its mass, they calculate, it would have failed to clear asteroids out--and Earth might have been struck four times more often than it has been. But if Jupiter were still smaller, it would have flung fewer asteroids toward the inner solar system to begin with--and the dinosaurs might still be walking our planet. --George Musser
[More]The first results from a powerful gamma-ray telescope launched into orbit earlier this summer show it is on track to unlock new secrets of the most energetic explosions in the universe. That was the message from NASA researchers speaking at a teleconference this afternoon to present the findings and to announce the mission's new name. [More]
The first results from a powerful gamma-ray telescope launched into orbit earlier this summer show it is on track to unlock new secrets of the most energetic explosions in the universe. That was the message from NASA researchers speaking at a teleconference this afternoon to present the findings and to announce the mission's new name. [More]
Researchers say they have figured out how a mysterious clutch of massive stars could have come into existence a few trillion miles from the supermassive black hole at the center of the Milky Way. [More]
Researchers say they have figured out how a mysterious clutch of massive stars could have come into existence a few trillion miles from the supermassive black hole at the center of the Milky Way. [More]
Buzz Aldrin, the second man to walk on the moon, talks about solar energy, buses between the planets, the Constellation program, his time on the moon and his new animated movie, Fly Me to the Moon. Plus, we'll test your knowledge of some recent science in the news. Web sites mentioned in this episode include www.snipurl.com/aldrin; www.sciamdigital.com; www.flymetothemoonthemovie.com
> Related Story: Buzz Aldrin Flies to the Moon Again
[More]Buzz Aldrin, the second man to walk on the moon, talks about solar energy, buses between the planets, the Constellation program, his time on the moon and his new animated movie, Fly Me to the Moon. Plus, we'll test your knowledge of some recent science in the news. Web sites mentioned in this episode include www.snipurl.com/aldrin; www.sciamdigital.com; www.flymetothemoonthemovie.com
> Related Story: Buzz Aldrin Flies to the Moon Again
[More]Defining the Line “The Doping Dilemma,” by Michael Shermer, suggests that the possible penalties of using artificial enhancements in sports should be made greater than the possible rewards. But it is impossible to determine what is and is not an unacceptable artificial enhancement. With advances in medicine, biology and even prosthetics, the broad gray line will only get wider and murkier. We have reached the stage in our “progress” where meaningful contests between individuals are no longer possible.
[More]Defining the Line “The Doping Dilemma,” by Michael Shermer, suggests that the possible penalties of using artificial enhancements in sports should be made greater than the possible rewards. But it is impossible to determine what is and is not an unacceptable artificial enhancement. With advances in medicine, biology and even prosthetics, the broad gray line will only get wider and murkier. We have reached the stage in our “progress” where meaningful contests between individuals are no longer possible.
[More]