Jacques de Vaucanson (Feb. 24, 1709 - Nov. 21, 1782) was the French inventor of 'automata' - robot devices of later significance for modern industry. In 1737-38, he produced a transverse flute player, a pipe and tabor player, and a mechanical duck, which was especially noteworthy, not only imitating the motions of a live duck, but also the motions of drinking, eating, and "digesting." link
Saturday, February 24, 2007
Thursday, February 22, 2007
Light and Matter United
Albert Einstein and just about every other physicist insisted that light travels 186,000 miles a second in free space, and that it can't be speeded-up or slowed down. But in 1998, Lene Hau, for the first time in history, slowed light to 38 miles an hour, about the speed of rush-hour traffic.
From an article by William Cromie:
Two years later, she brought light to a complete halt in a cloud of ultracold atoms. Next, she restarted the stalled light without changing any of its characteristics, and sent it on its way.
Now her team has made a light pulse disappear from one cold cloud then retrieved it from another cloud nearby. In the process, light was converted into matter then back into light. For the first time in history, this gives science a way to control light with matter and vice versa.
That's how light moves darkly from one cloud to another in Hau's laboratory. This invisible wave of matter keeps going unless it's stopped in the second cloud with another laser beam, after which it can be revived as light again.
From an article by William Cromie:
Two years later, she brought light to a complete halt in a cloud of ultracold atoms. Next, she restarted the stalled light without changing any of its characteristics, and sent it on its way.
Now her team has made a light pulse disappear from one cold cloud then retrieved it from another cloud nearby. In the process, light was converted into matter then back into light. For the first time in history, this gives science a way to control light with matter and vice versa.
Forever People © DC Comics
A weird thing happens to the light as it enters the cold atomic cloud, called a Bose-Einstein condensate. Atoms at room temperature move in a random, chaotic way. But when chilled in a vacuum to about 460 degrees below zero Fahrenheit, under certain conditions millions of atoms lock together and behave as a single mass. When a laser beam enters such a condensate, the light leaves an imprint on a portion of the atoms. That imprint moves like a wave through the cloud and exits at a speed of about 700 feet per hour. This wave of matter will keep going and enter another nearby ultracold condensate. That's how light moves darkly from one cloud to another in Hau's laboratory. This invisible wave of matter keeps going unless it's stopped in the second cloud with another laser beam, after which it can be revived as light again.
Coherent control of optical information with matter wave dynamics. Naomi S. Ginsberg, Sean R. Garner, Lene Vestergaard Hau. Nature 445:623-626, 2007.PLEASE STAND BY!
Wednesday, February 21, 2007
Monday, February 19, 2007
The Hyborian Age: Chapter Five
CLICK ON EACH TO ENLARGE AND READ
Script by Roy Thomas; Art © Walt Simonson;
The Hyborian Age and Conan © their current copyright holders.
Read:
Chapter One
Chapter Two
Chapter Three
Chapter Four
Friday, February 16, 2007
Opened This Day: Tutankhamen's Tomb
On this day in 1923, archaeologist Howard Carter opened the sealed doorway to the sepulchral chamber of King Tutankhamen's tomb in Thebes, Egypt. A group of invited visitors and officials was present, including Lord Carnarvon, the aristocratic Englishman who had funded the excavation. link
Art by Roy G. Krenkel. Creepy is © and™ Warren Publishing Company.
CLICK IMAGE TO ENLARGE.
The Mummy gets Funky in The Mad Monster Party:
Wednesday, February 14, 2007
Bats Prey On Nocturnally Migrating Songbirds
It was previuosly believed that nocturnally migrating songbirds could stop their anti-predator vigilance at night. A new study shows that the giant noctule bat, Nyctalus lasiopterus, exploits [eats] the billions of Eurasian songbirds when the birds' flight routes converge around the Mediterranean basin, such as the Iberian Peninsula.
They showed that the bats ate only insects in summer, included some songbirds' flesh in their diet during spring, and depended a great deal on passerines during autumn. Moreover, a higher fraction of songbirds' flesh in autumn than in spring was attributed to the more massive passerine migration in autumn, because both parents and offspring migrate then towards their wintering grounds in Africa.
The Noctural Predator In Action:
Bats Conquest of a Formidable Foraging Niche: The Myriads of Nocturnally Migrating Songbirds. 2007. Citation: A.G. P.-Lisseanu et al. PLoS ONE 2(2): e205.
They showed that the bats ate only insects in summer, included some songbirds' flesh in their diet during spring, and depended a great deal on passerines during autumn. Moreover, a higher fraction of songbirds' flesh in autumn than in spring was attributed to the more massive passerine migration in autumn, because both parents and offspring migrate then towards their wintering grounds in Africa.
Nyctalus lasiopterus. Credit: Ana Popa-Lisseanu
The ability of giant noctules to prey on the wing upon nocturnally migrating passerines appears unique not only among bats but also within the whole animal kingdom. The unique ecological niche of the giant noctule may in turn explain some of its peculiar natural history traits. First, the species occurs almost exclusively in some restricted parts of the Mediterranean where major streams of migrating birds congregate. Second, it is among the largest Palaeartic bats and even belongs to the heaviest aerial-hunting bats of the world, a prerequisite for subduing prey items as large as passerines. Link: press releaseThe Noctural Predator In Action:
Bats Conquest of a Formidable Foraging Niche: The Myriads of Nocturnally Migrating Songbirds. 2007. Citation: A.G. P.-Lisseanu et al. PLoS ONE 2(2): e205.
Monday, February 12, 2007
How To Ingite A Cosmic Lighthouse
Researchers have been able to show that all supernovae of a certain type explode with the same mass and the same energy - the brightness depends only on how much nickel the supernova contains. This knowledge has allowed the researchers to calibrate the brightness of supernovae with greater precision. This means that in the future, they will use the brightness of a supernova that they are observing through their telescopes to determine more accurately how far away from the Earth the cosmic lighthouse is emitting its rays.
The arrow points to the supernova 2002bo, the explosion of a white dwarf in the galaxy NGC 3190 in the Leo constellation--60 million light years away from earth.Image: Benetti et al., MNRAS 384:261-278 (2004)
All supernovae have low-velocity cores of stable iron-group elements. Outside this core, nickel-56 dominates the supernova ejecta. The outer extent of the iron-group material depends on the amount of nickel-56 and coincides with the inner extent of silicon, the principal product of incomplete burning. The outer extent of the bulk of silicon is similar in all supernovae, having an expansion velocity of 11,000 kilometers per second and corresponding to a mass of slightly over one solar mass. This indicates that all the supernovae considered here burned similar masses and suggests that their progenitors had the same mass. link
A Common Explosion Mechanism for Type Ia Supernovae. 2007. P.A. Mazzali et al. Science.
Hey, Where's Capt. Kirk!?
The arrow points to the supernova 2002bo, the explosion of a white dwarf in the galaxy NGC 3190 in the Leo constellation--60 million light years away from earth.Image: Benetti et al., MNRAS 384:261-278 (2004)
All supernovae have low-velocity cores of stable iron-group elements. Outside this core, nickel-56 dominates the supernova ejecta. The outer extent of the iron-group material depends on the amount of nickel-56 and coincides with the inner extent of silicon, the principal product of incomplete burning. The outer extent of the bulk of silicon is similar in all supernovae, having an expansion velocity of 11,000 kilometers per second and corresponding to a mass of slightly over one solar mass. This indicates that all the supernovae considered here burned similar masses and suggests that their progenitors had the same mass. link
A Common Explosion Mechanism for Type Ia Supernovae. 2007. P.A. Mazzali et al. Science.
Hey, Where's Capt. Kirk!?
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