How sticky toepads evolved in geckos


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Nature News wouldn’t leave an embarrassing problem like this unresolved, would it?  Moerchen offered some suggestions, but alas, confessed, “However, these hypotheses… can be excluded…”  Then she offered the authors’ favored two solutions, but added, “However, both models have unresolved issues.”  A couple of other solutions were put forth unenthusiastically, because they are catastrophic: the runaway accretion model, and the collisional cascade model, “in which gravitationally bound dust grains experience successive cratering or wholly destructive collisions that eventually yield grains small enough to be blown out of the system” –  i.e., complete pulverization to smithereens. 

  • Nature News wouldn’t leave an embarrassing problem like this unresolved, would it?  Moerchen offered some suggestions, but alas, confessed, “However, these hypotheses… can be excluded…”  Then she offered the authors’ favored two solutions, but added, “However, both models have unresolved issues.”  A couple of other solutions were put forth unenthusiastically, because they are catastrophic: the runaway accretion model, and the collisional cascade model, “in which gravitationally bound dust grains experience successive cratering or wholly destructive collisions that eventually yield grains small enough to be blown out of the system” –  i.e., complete pulverization to smithereens. 



That’s hardly conducive to planet formation, which is what the planetesimal hypothesis purports to explain.

  • That’s hardly conducive to planet formation, which is what the planetesimal hypothesis purports to explain.

  • Moerchen ended with the best positive spin she could muster, commenting that “the extremely rapid changes in this dusty system are certain to provoke further discussion of planetary-system evolution.”  Indeed, the authors themselves confessed in their abstract, “Such a phase of rapid ejecta evolution has not been previously predicted or observed, and no currently available physical model satisfactorily explains the observations.”  Her final paragraph is a model of theory-rescuing rhetoric in the face of evidential disaster:



The disappearance of the excess infrared radiation from TYC 8241 2652 1 in less than two years is incredibly fast by our current understanding, and the impact of this is difficult to predict. The dust-clearing models proposed by Melis et alcould be refined to bring them more into line with conventional theory. And theories that have been developed for other stars and that were adapted to TYC 8241 2652 1 could be redeveloped. However, perhaps the most exciting possibility is that the brightness drop represents a stage of terrestrial-planet formation that occurs so quickly that we have not been lucky enough to glimpse it until now.

  • The disappearance of the excess infrared radiation from TYC 8241 2652 1 in less than two years is incredibly fast by our current understanding, and the impact of this is difficult to predict. The dust-clearing models proposed by Melis et alcould be refined to bring them more into line with conventional theory. And theories that have been developed for other stars and that were adapted to TYC 8241 2652 1 could be redeveloped. However, perhaps the most exciting possibility is that the brightness drop represents a stage of terrestrial-planet formation that occurs so quickly that we have not been lucky enough to glimpse it until now.



How did the popular press report this anomaly?  PhysOrg led off with the banal evolutionary formula, “New study sheds new light on planet formation.”   The press release from University of Georgia featured home boy Inseok Song standing proudly by his telescope while the university’s spin machine turned the anomaly into a victory for evolution theory: “A study published in the July 5 edition of the journal Nature is challenging scientists’ understanding of planet formation, suggesting that planets might form much faster than previously thought or, alternatively, that stars harboring planets could be far more numerous.”  Yes, that’s right: instead of millions of years, planets might form in a few!  Think of the possibilities that “new light” allows: rapidly forming planets could now be much more common!  The press release author seemed to take liberties with Song’s more humble interpretation of the unexpected finding:

  • How did the popular press report this anomaly?  PhysOrg led off with the banal evolutionary formula, “New study sheds new light on planet formation.”   The press release from University of Georgia featured home boy Inseok Song standing proudly by his telescope while the university’s spin machine turned the anomaly into a victory for evolution theory: “A study published in the July 5 edition of the journal Nature is challenging scientists’ understanding of planet formation, suggesting that planets might form much faster than previously thought or, alternatively, that stars harboring planets could be far more numerous.”  Yes, that’s right: instead of millions of years, planets might form in a few!  Think of the possibilities that “new light” allows: rapidly forming planets could now be much more common!  The press release author seemed to take liberties with Song’s more humble interpretation of the unexpected finding:



“The most commonly accepted time scale for the removal of this much dust is in the hundreds of thousands of years, sometimes millions,” said study co-author Inseok Song, assistant professor of physics and astronomy in the UGA Franklin College of Arts and Sciences. “What we saw was far more rapid and has never been observed or even predicted. It tells us that we have a lot more to learn about planet formation.

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