Science & Technology
As Egyptian mummies go, Asru is a major celebrity. During her life in the 8th century B.C., she was known for her singing at the temple of Amun in Karnak; now she's famous for her medical problems. Forensic studies have revealed that although Asru lived into her 60s, she was not a well woman. She had furred-up arteries, desert lung (pneumoconiosis) caused by breathing in sand, osteoarthritis, a slipped disc, periodontal disease and possibly diabetes, as well as parasitic worms in her intestine and bladder. Her last years must have been full of pain and suffering. After all, what could her doctor do to help? Say a few prayers and recite a spell or two?
Organic molecules - in the form of methane - have been detected on a planet outside our solar system for the first time. The giant planet lies too close to its parent star for the methane to signal life, but the detection offers hope that astronomers will one day be able to analyse the atmospheres of Earth-like worlds.
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| ©Christophe Carreau/ESA |
| The giant planet HD 189733b is too hot for its methane and water vapour to signal life |
June is a time for beach parties and barbecues. It is a time for wildflowers and warm breezes and slow summer evenings. It is a time when our sun-orbiting planet cuts across a trail of cosmic debris, scattered by a monster comet, that one fine day may visit a holocaust upon us.
So says astrophysicist Victor Clube of Oxford University. He's been studying the Taurids--a meteor shower that strikes Earth each year in late June and again in November. The Taurids are not nearly as spectacular as, say, the Perseids of August; in June they're not even visible, because they approach from the dayside of the planet. But Clube and his co-workers think the Taurids are underrated. The meteor stream, they say, includes rocks so large--as much as a mile across--that to see one up close would be to lose a city, a continent, or more.
So says astrophysicist Victor Clube of Oxford University. He's been studying the Taurids--a meteor shower that strikes Earth each year in late June and again in November. The Taurids are not nearly as spectacular as, say, the Perseids of August; in June they're not even visible, because they approach from the dayside of the planet. But Clube and his co-workers think the Taurids are underrated. The meteor stream, they say, includes rocks so large--as much as a mile across--that to see one up close would be to lose a city, a continent, or more.
© David Willacy/EyeEm/Getty Images
Not long after the telescope was invented at the beginning of the 17th century, astronomers came to realise that the Moon, our only natural satellite, was not as dynamic a world as the Earth. The dark lunar tracts which early astronomers had somewhat optimistically called "maria" (seas) turned out to be nothing more than deceptively smooth plains of solidified lava. Much to astronomers' disappointment it became apparent that there were no appreciable expanses of water, though the new romantic marine nomenclature was retained, regardless - names like Mare Crisium (the Sea of Crises) and Oceanus Procellarum (the Ocean of Storms) were given in a vain attempt to grant the Moon an air of mystery and excitement [1].
In reality, the Moon's surface appeared solid and unchanging. The Moon possessed no appreciable atmosphere and there were no detectable signs of lunar life; the Church breathed a sigh of relief, having been spared the embarrassment of attempting to explain why the book of Genesis forgot to mention that our sister planet was teeming with the products of DNA.
It is unlikely the dinosaurs perished in a global firestorm triggered by the asteroid strike on Earth 65 million years ago, scientists have claimed.
A popular theory suggests the impact, which was centred on Chicxulub in Mexico, generated enough energy to set off a raging worldwide inferno.
But a new study shows rocks laid down at the time contain little charcoal - a possible tell-tale record of fires.
The researchers have published details of their work in the journal Geology.
The wildfires theory had grown up from previous research. One study had even found evidence of soot in rocks from around the Earth dating to the time of the impact.
A popular theory suggests the impact, which was centred on Chicxulub in Mexico, generated enough energy to set off a raging worldwide inferno.
But a new study shows rocks laid down at the time contain little charcoal - a possible tell-tale record of fires.
The researchers have published details of their work in the journal Geology.
The wildfires theory had grown up from previous research. One study had even found evidence of soot in rocks from around the Earth dating to the time of the impact.
More confusion at the k-t boundary
Just a few years ago, many scientists, especially physicists and astronomers, considered the Book of Science to be closed in the matter of what happened at the Cretaceous-Tertiary (K-T) boundary, 65 million years ago, and why the dinosaurs met their end. It was declared, rather imperiously, that a large asteroid had impacted the earth, causing much physical and biological devastation. Many scientific papers are still being written on this singular period in the earth's history, and the situation is no longer so clear-cut. We select for brief review four papers, each with a different perspective.
Occurrence of stishovite. Stishovite, a dense phase of silica, is widely accepted as an indicator of terrestrial impact events. It is not found at volcanic sites. Now, J.F. McHone et al report its existence at the K-T boundary, at Raton, New Mexico. (McHone, John F., et al; "Stishovite at the CretaceousTertiary Boundary, Raton, New Mexico," Science, 243:1182, 1989.) A plus for the pro-impact side.
Just a few years ago, many scientists, especially physicists and astronomers, considered the Book of Science to be closed in the matter of what happened at the Cretaceous-Tertiary (K-T) boundary, 65 million years ago, and why the dinosaurs met their end. It was declared, rather imperiously, that a large asteroid had impacted the earth, causing much physical and biological devastation. Many scientific papers are still being written on this singular period in the earth's history, and the situation is no longer so clear-cut. We select for brief review four papers, each with a different perspective.
Occurrence of stishovite. Stishovite, a dense phase of silica, is widely accepted as an indicator of terrestrial impact events. It is not found at volcanic sites. Now, J.F. McHone et al report its existence at the K-T boundary, at Raton, New Mexico. (McHone, John F., et al; "Stishovite at the CretaceousTertiary Boundary, Raton, New Mexico," Science, 243:1182, 1989.) A plus for the pro-impact side.
The dinosaurs dominated the landscape for 160 million years, living over a thousand times longer than modern humans (Homo sapiens first evolved about 150 thousand years ago). During this vast stretch of time some dinosaur species became extinct, but overall the impression is one of an immensely tough class of animals that could endure whatever hardships the planet managed to throw at it. When the end finally came, it came from beyond Earth.
A meteorite impact 65 million years ago is the simple explanation for the extinction of the dinosaurs. The exact details are much more complex, and researchers are still trying to nail down exactly what happened. The Cretaceous-Tertiary (K-T) extinction event is like an ancient tapestry that has become matted and soiled due to time and neglect. There are hundreds of threads of evidence that need to be untangled, smoothed out, and put in their proper place before a clear picture can emerge.
A meteorite impact 65 million years ago is the simple explanation for the extinction of the dinosaurs. The exact details are much more complex, and researchers are still trying to nail down exactly what happened. The Cretaceous-Tertiary (K-T) extinction event is like an ancient tapestry that has become matted and soiled due to time and neglect. There are hundreds of threads of evidence that need to be untangled, smoothed out, and put in their proper place before a clear picture can emerge.
In 1993, J. Richard Gott III computed with scientific certainty that humanity would survive at least 5,100 more years. At the time, I took that as reason to relax, but Dr. Gott has now convinced me I was wrong. He has issued a wake-up call: To ensure our long-term survival, we need to get a colony up and running on Mars within 46 years.
If you're not awakened yet, I understand. It's only prudent to be skeptical of people who make scientific forecasts about the end of humanity. Dr. Gott, a professor of astrophysics at Princeton, got plenty of grief after he made his original prediction in 1993. But in the ensuing 14 years, his prophetic credentials have strengthened, and not merely because humanity is still around.
If you're not awakened yet, I understand. It's only prudent to be skeptical of people who make scientific forecasts about the end of humanity. Dr. Gott, a professor of astrophysics at Princeton, got plenty of grief after he made his original prediction in 1993. But in the ensuing 14 years, his prophetic credentials have strengthened, and not merely because humanity is still around.
IN HIS ARTICLE "A Gaian Politics" (WER #53, p.4), historian William Irwin Thompson asks: "What would be the slightest and subtlest of moves that could transform our present political environment from one of terror to a life-centered polity of compassion?" He goes on to say that the martial arts teach us to appraise the situation as given and look for ways to redirect the energies manifested toward positive goals. As an example, Thompson suggests that the Strategic Defense Initiative (SDI) could be transformed into a transnational program for the exploration of space.
But would the mysteries of Mars provide sufficient cement to bind opposing parties long enough for their mutual paranoia to wane? Thompson laments that, even if desired, transformation is difficult for a nation with an economy built around preparation for war. The military component must be reduced slowly as employment is shifted to other areas--a task next to impossible without government subsidies. The problem, he states, "is that citizens and politicians will only vote for subsidies under threat, and so there always has to be a threat from the enemy or the environment to mobilize a society."
But would the mysteries of Mars provide sufficient cement to bind opposing parties long enough for their mutual paranoia to wane? Thompson laments that, even if desired, transformation is difficult for a nation with an economy built around preparation for war. The military component must be reduced slowly as employment is shifted to other areas--a task next to impossible without government subsidies. The problem, he states, "is that citizens and politicians will only vote for subsidies under threat, and so there always has to be a threat from the enemy or the environment to mobilize a society."
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| ©NASA/JPL-Caltech/Cornell University |
Comment: What they didn't consider is multiple smaller impacts as well as a larger one off Yucatan, AND overhead cometary fragment explosions.