Tag: science

Is Anything at Rest in the Universe?

Is Anything at Rest in the Universe?

In the year 1851 cultivated persons in cities throughout Europe went to the largest cathedrals to attend an unusual sort of worship. They were coming to witness Jean Foucault’s pendulum experiment, which he had first performed for the public in that year under the dome of the Pantheon in Paris.

From the highest point in the cathedral a heavy weight hung suspended on a thin rope, so that it was free to swing in all directions. it was given a push in a northerly direction, and began to swing in a north-south line. It continued to swing for days, but ever so slowly the direction of its swing shifted. And it continued to do so visibly. Those who waited long enough were able to see the plane of the pendulum’s swing turn in a full circle in the course of a day.

Actually, however, the plane of oscillation had not change d at all. A pendulum retains the direction of its original motion, as stated by Galileo’s law of inertia. Thus the pendulum provided visible proof of Copernicus’ doctrine: the Earth was turning underneath the swinging pendulum.

How unfortunate it was that Galileo did not notice this when he observed the chandelier swinging in the Duomo at Pisa. He would have been spared his troubles with the Inquisition; such tangible proof of the Earth’s rotation would have silenced all doubts.

Nevertheless, the Frenchman’s ingenious experiment stimulated other ideas, for which the times and the place were ready: ideas on one of the fundamental problems of both philosophy and religion.

Originally Newton had asked himself whether absolute movement existed in the universe, that is to say, movement in itself which we could determine without reference to other movements. His answer was that there was only one such motion: the rotation of the Earth. Ultimately, he maintained, we would have discovered this motion even if there had not been a sky full of stars circling about the polestar above our heads. Even without the polestar we would have found the flattened poles of our globe; we would have understood that they had been caused by the distorting effect of centrifugal force.

From this reasoning Newton drew a profound conclusion. If we imagine our universe with no other bodies beside the Earth, there must still be something to which we can refer the motion of the Earth, something that is at rest in relation to the Earth. Absolute motion presupposes something absolutely at rest. Only space can be this something. Hence, space ceases to be solely a philosophical concept, a mere word; it must have physical existence, for all that its only characteristic is being at rest. This idea of something at rest, ubiquitous, absolutely fixed, suggested the attributes of the Supreme Being; physical space of its own accord intruded itself into the sphere of religion.

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Rare ancient seal found in Jerusalem

.Rare ancient seal found in Jerusalem

The coin-sized artifact appears to be linked to religious rituals 2,000 years ago.

A rare clay seal found under Jerusalem’s Old City appears to be linked to religious rituals practiced at the Jewish Temple 2,000 years ago, Israeli archaeologists said Sunday.

The coin-sized seal found near the Jewish holy site at the Western Wall bears two Aramaic words meaning “pure for God.”

Archaeologist Ronny Reich of Haifa University said it dates from between the 1st century B.C. to 70 A.D. — the year Roman forces put down a Jewish revolt and destroyed the second of the two biblical temples in Jerusalem.

The find marks the first discovery of a written seal from that period of Jerusalem’s history, and appeared to be a unique physical artifact from ritual practice in the Temple, said Reich, co-director of the excavation.

Very few artifacts linked to the Temples have been discovered so far. The site of the Temple itself — the enclosure known to Jews as the Temple Mount and to Muslims as the Noble Sanctuary — remains off-limits to archaeologists because of its religious and political sensitivity.

Archaeologists say the seal was likely used by Temple officials approving an object for ritual use — oil, perhaps, or an animal intended for sacrifice. Materials used by Temple priests had to meet stringent purity guidelines stipulated in detail in the Jewish legal text known as the Mishna, which also mention the use of seals as tokens by pilgrims.

The find, Reich said, is “the first time an indication was brought by archaeology about activities in the Temple Mount — the religious activities of buying and offering and giving to the Temple itself.”

The site where the seal was found is on the route of a main street that ran through ancient Jerusalem just outside the Temple compound.

Aren Maeir of Bar-Ilan University, a biblical archaeologist not connected to the dig, said the seal was special because it “was found right next to the Temple and is similar to what we see described in the Mishna.”

“It’s nice when we can connect an activity recorded in ancient sources with archaeological finds,” he said.

The seal was found in an excavation run by archaeologists from the government’s Israel Antiquities Authority. The dig is under the auspices of a broader dig nearby known as the City of David, where archaeologists are investigating the oldest part of Jerusalem.

The City of David dig, located inside the nearby Palestinian neighborhood of Silwan and funded by a Jewish group affiliated with the settlement movement, is the Holy Land’s highest-profile and most politically controversial excavation.

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Aussie student cracks a cosmic mystery

Aussie student finds universe's 'missing mass'

A 22-year-old woman on summer break solves a problem that has vexed scientists for decades.

A 22-year-old Australian university student has solved a problem which has puzzled astrophysicists for decades, discovering part of the so-called “missing mass” of the universe during her summer break.

Undergraduate Amelia Fraser-McKelvie made the breakthrough during a holiday internship with a team at Monash University’s School of Physics, locating the mystery material within vast structures called “filaments of galaxies”.

Monash astrophysicist Dr Kevin Pimbblet explained that scientists had previously detected matter that was present in the early history of the universe but that could not now be located.

“There is missing mass, ordinary mass not dark mass… It’s missing to the present day,” Pimbblet told AFP.

“We don’t know where it went. Now we do know where it went because that’s what Amelia found.”

Fraser-McKelvie, an aerospace engineering and science student, was able to confirm after a targeted X-ray search for the mystery mass that it had moved to the “filaments of galaxies”, which stretch across enormous expanses of space.

Pimbblet’s earlier work had suggested the filaments as a possible location for the “missing” matter, thought to be low in density but high in temperature.

Pimbblet said astrophysicists had known about the “missing” mass for the past two decades, but the technology needed to pinpoint its location had only become available in recent years.

He said the discovery could drive the construction of new telescopes designed to specifically study the mass.

Pimbblet admitted the discovery was primarily academic, but he said previous physics research had led to the development of diverse other technologies.

“Whenever I speak to people who have influence, politicians and so on, they sometimes ask me ‘Why should I invest in physics pure research?’. And I sometimes say to them: ‘Do you use a mobile phone? Some of that technology came about by black hole research’.

“The pure research has knock-on effects to the whole society which are sometimes difficult to anticipate.”

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Total lunar eclipse coming Monday night

Total lunar eclipse coming Monday night

Skywatchers will have a view of one of nature’s most beautiful spectacles if the weather is clear.

For a few hours on the night of Dec. 20 to Dec. 21, the attention of tens of millions of people will be drawn skyward, where the mottled, coppery globe of our moon will hang completely immersed in the long, tapering cone of shadow cast out into space by our Earth. If the weather is clear, favorably placed skywatchers will have a view of one of nature’s most beautiful spectacles: a total eclipse of the moon.

Unlike a total eclipse of the sun, which is only visible to those in the path of totality, eclipses of the moon can usually be observed from one’s own backyard. The passage of the moon through the Earth’s shadow is equally visible from all places within the hemisphere where the moon is above the horizon.

The total phase of the upcoming event will be visible across all of North and South America, as well as the northern and western part of Europe, and a small part of northeast Asia, including Korea and much of Japan. Totality will also be visible in its entirety from the North Island of New Zealand and Hawaii — a potential viewing audience of about 1.5 billion people. This will be the first opportunity from any place on earth to see the moon undergo a total eclipse in 34 months. [Amazing photos of a total lunar eclipse]

This star chart shows where in the sky the upcoming lunar eclipse will appear. And check this NASA lunar eclipse chart to see how visible the eclipse will be from different regions around the world.

Stages of the eclipse

There is nothing complicated about viewing this celestial spectacle. Unlike an eclipse of the sun, which necessitates special viewing precautions in order to avoid eye damage, an eclipse of the moon is perfectly safe to watch. All you’ll need to watch are your eyes, but binoculars or a telescope will give a much nicer view.

The eclipse will actually begin when the moon enters the faint outer portion, or penumbra, of the Earth’s shadow a little over an hour before it begins moving into the umbra. The penumbra, however, is all but invisible to the eye until the moon becomes deeply immersed in it. Sharp-eyed viewers may get their first glimpse of the penumbra as a faint smudge on the left part of the moon’s disk at or around 6:15 UT (on Dec. 21) which corresponds to 1:15 a.m. Eastern Time or 10:15 p.m. Pacific Time (on Dec. 20).

The most noticeable part of this eclipse will come when the moon begins to enter the Earth’s dark inner shadow (called the umbra). A small scallop of darkness will begin to appear on the moon’s left edge at 6:33 UT (on Dec. 21) corresponding to 1:33 a.m. EST or 10:33 p.m. PST (on Dec. 20).

The moon is expected to take 3 hours and 28 minutes to pass completely through the umbra.

The total phase of the eclipse will last 72 minutes beginning at 7:41 UT (on Dec. 21), corresponding to 2:41 a.m. EST or 11:41 p.m. PST (on Dec. 20).

At the moment of mid-totality (8:17 UT/3:17 a.m. EST/12:17 a.m. PST), the moon will stand directly overhead from a point in the North Pacific Ocean about 800 miles (1,300 km) west of La Paz, Mexico.

The moon will pass entirely out of the Earth’s umbra at 10:01 UT/5:01 a.m. EST/2:01 a.m. PST and the last evidence of the penumbra should vanish about 15 or 20 minutes later.

Color and brightness in question

During totality, although the moon will be entirely immersed in the Earth’s shadow, it likely will not disappear from sight. Rather, it should appear to turn a coppery red color, a change caused by the Earth’s atmosphere bending or refracting sunlight into the shadow.

Since the Earth’s shadow is cone-shaped and extends out into space for about 844,000 miles (1,358,000 km), sunlight will be strained through a sort of “double sunset,” all around the rim of the Earth, into its shadow and then onto the moon.

However, because of the recent eruptions of the Eyjafjallajkull volcano last spring and the Merapi volcano in Indonesia in October, one and possibly even two clouds of ash and dust might be floating high above the Earth. As a result, the moon may appear darker than usual during this eclipse; during totality, parts of the moon might even become black and invisible.

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Mystery of how cats drink finally solved

Mystery of how cats drink finally solved

It took a team of researchers with high-speed video cameras to unlock the feline secret.

US researchers on Thursday unveiled the secret of how cats lap water or milk with such elegance, a phenomenon that happens so fast it cannot be followed by human eyes. Cats are among the many species that, unlike humans, cannot close their mouths and create suction.

With help from from high-speed video taken of a felines lapping liquid, researchers at the Massachusetts Institute of Technology (MIT) and Princeton University found that household cats and larger felines like tigers balance gravity and inertia as they imbibe liquids.

The research will appear in the November 12 issue of the journal Science. Scientists already knew that when cats insert their tongue into a bowl of liquid, the top surface of the tongue touches the liquid first, then the tip curves like a letter J to form a sort of ladle.

This was first observed by an MIT engineer, who filmed a cat lapping liquid in 1940. However by studying the images researchers have now determined that there is no ladling effect, but instead the cat’s tongue darts in and out so quickly that the action forms a column of liquid.

“Cats, unlike dogs, aren’t dipping their tongues into the liquid like ladles after all,” read a statement from the MIT Department of Civil and Environmental Engineering.

Instead, the smooth tip of cat’s tongue “barely brushes the surface of the liquid before the cat rapidly draws its tongue back up. “As it does so, a column of milk forms between the moving tongue and the liquid’s surface. The cat then closes its mouth, pinching off the top of the column for a nice drink, while keeping its chin dry.”

The liquid column “is created by a delicate balance between gravity, which pulls the liquid back to the bowl, and inertia, which in physics, refers to the tendency of the liquid or any matter, to continue moving in a direction unless another force interferes.”

The cat “instinctively knows just how quickly to lap in order to balance these two forces, and just when to close its mouth. If it waits another fraction of a second, the force of gravity will overtake inertia, causing the column to break, the liquid to fall back into the bowl, and the cat’s tongue to come up empty.”

Cats average about four laps per second, with each lap bringing in about 0.1 milliliters of liquid, the researchers said, adding that larger felines lap at a slower pace.

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Could new found planet be just right for life?

Could new found planet be just right for life?

Not too hot and not too cold, the first-time discovery offers conditions with rare potential.

Astronomers say they have for the first time spotted a planet beyond our own in what is sometimes called the Goldilocks zone for life: Not too hot, not too cold. Just right.

Not too far from its star, not too close. So it could contain liquid water. The planet itself is neither too big nor too small for the proper surface, gravity and atmosphere.

It’s just right. Just like Earth. “This really is the first Goldilocks planet,” said co-discoverer R. Paul Butler of the Carnegie Institution of Washington.

The new planet sits smack in the middle of what astronomers refer to as the habitable zone, unlike any of the nearly 500 other planets astronomers have found outside our solar system. And it is in our galactic neighborhood, suggesting that plenty of Earth-like planets circle other stars.

Finding a planet that could potentially support life is a major step toward answering the timeless question: Are we alone?

Scientists have jumped the gun before on proclaiming that planets outside our solar system were habitable only to have them turn out to be not quite so conducive to life. But this one is so clearly in the right zone that five outside astronomers told The Associated Press it seems to be the real thing.

“This is the first one I’m truly excited about,” said Penn State University’s Jim Kasting. He said this planet is a “pretty prime candidate” for harboring life. Life on other planets doesn’t mean E.T. Even a simple single-cell bacteria or the equivalent of shower mold would shake perceptions about the uniqueness of life on Earth.

But there are still many unanswered questions about this strange planet. It is about three times the mass of Earth, slightly larger in width and much closer to its star — 14 million miles away versus 93 million. It’s so close to its version of the sun that it orbits every 37 days. And it doesn’t rotate much, so one side is almost always bright, the other dark.

Temperatures can be as hot as 160 degrees or as frigid as 25 degrees below zero, but in between — in the land of constant sunrise — it would be “shirt-sleeve weather,” said co-discoverer Steven Vogt of the University of California at Santa Cruz.

It’s unknown whether water actually exists on the planet, and what kind of atmosphere it has. But because conditions are ideal for liquid water, and because there always seems to be life on Earth where there is water, Vogt believes “that chances for life on this planet are 100 percent.”

The astronomers’ findings are being published in Astrophysical Journal and were announced by the National Science Foundation on Wednesday. The planet circles a star called Gliese 581. It’s about 120 trillion miles away, so it would take several generations for a spaceship to get there. It may seem like a long distance, but in the scheme of the vast universe, this planet is “like right in our face, right next door to us,” Vogt said in an interview.

That close proximity and the way it was found so early in astronomers’ search for habitable planets hints to scientists that planets like Earth are probably not that rare. Vogt and Butler ran some calculations, with giant fudge factors built in, and figured that as much as one out of five to 10 stars in the universe have planets that are Earth-sized and in the habitable zone

With an estimated 200 billion stars in the universe, that means maybe 40 billion planets that have the potential for life, Vogt said. However, Ohio State University’s Scott Gaudi cautioned that is too speculative about how common these planets are.

Vogt and Butler used ground-based telescopes to track the star’s precise movements over 11 years and watch for wobbles that indicate planets are circling it. The newly discovered planet is actually the sixth found circling Gliese 581. Two looked promising for habitability for a while, another turned out to be too hot and the fifth is likely too cold. This sixth one bracketed right in the sweet spot in between, Vogt said.

With the star designated “a,” its sixth planet is called Gliese 581g. “It’s not a very interesting name and it’s a beautiful planet,” Vogt said. Unofficially, he’s named it after his wife: “I call it Zarmina’s World.”

The star Gliese 581 is a dwarf, about one-third the strength of our sun. Because of that, it can’t be seen without a telescope from Earth, although it is in the Libra constellation, Vogt said. But if you were standing on this new planet, you could easily see our sun, Butler said.

The low-energy dwarf star will live on for billions of years, much longer than our sun, he said. And that just increases the likelihood of life developing on the planet, the discoverers said. “It’s pretty hard to stop life once you give it the right conditions,” Vogt said.

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An unusual change in the northern lights

Northern Lights hit 100-year low point

The aurora borealis has become a rarer sight than at any other time in the past 100 years.

The Northern Lights have petered out during the second half of this decade, becoming rarer than at any other time in more than a century, the Finnish Meteorological Institute said Tuesday.

The Northern Lights, or aurora borealis, generally follow an 11-year “solar cycle”, in which the frequency of the phenomena rises to a maximum and then tapers off into a minimum and then repeats the cycle.

“The solar minimum was officially in 2008, but this minimum has been going on and on and on,” researcher Noora Partamies told AFP.

“Only in the past half a year have we seen more activity, but we don’t really know whether we’re coming out of this minimum,” she added.

The Northern Lights, a blaze of coloured patterns in the northern skies, are triggered by solar winds crashing into the earth and being drawn to the magnetic poles, wreaking havoc on electrons in the parts of the atmosphere known as the ionosphere and magnetosphere.

So a dimming of the Northern Lights is a signal that activity on the sun which causes solar winds, such as solar flares and sun sports, is also quieting down.

For researchers like Partamies, it is the first time they can observe through a network of modern observation stations what happens to this solar cycle when it becomes as badly disrupted as it is now.

“We’re waiting to see what happens, is the next maximum going to be on time, is it going to be late, is it going to be huge?” Partamies said.

During the cycle’s peak in 2003, the station on Norway’s Svalbard island near the North Pole, showed that the Northern Lights were visible almost every single night of the auroral season, which excludes the nightless summer months.

That figure has fallen to less than 50y percent, while the southernmost station, situated in southern Finland, has been registering only two to five instances annually for the past few years.

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Two new dinosaur species discovered

Two new dinosaur species discovered

Scientists said Wednesday they’ve discovered fossils in the southern Utah desert of two new dinosaur species closely related to the Triceratops, including one with 15 horns on its large head.

The discovery of the new plant-eating species — including Kosmoceratops richardsoni, considered the most ornate-headed dinosaur known to man — was reported Wednesday in the online scientific journal PLoS ONE, produced by the Public Library of Science.

The other dinosaur, which has five horns and is the larger of the two, was dubbed Utahceratops gettyi.

“It’s not every day that you find two rhino-sized dinosaurs that are different from all the other dinosaurs found in North America,” said Mark Loewen, a Utah Museum of Natural History paleontologist and an author of the paper published in PLoS ONE.

“You would think that we know everything there is to know about the dinosaurs of western North America, but every year we’re finding new things, especially here in Utah,” he said.

The Grand Staircase-Escalante National Monument has been a hotbed for dinosaur species discoveries in the past decade, with more than a dozen new species discovered. While it is a rocky, arid place now, millions of years ago it was similar to a swamp.

The Utahceratops has a large horn over the nose and short eye horns that project to the side rather than upward, similar to a bison. Its skull is about 7 feet long, it stood about 6 feet high and was 18 to 22 feet long. It is believed to have weighed about 3 to 4 tons.

The Kosmoceratops has similar facial features at the Utahceratops, but has 10 horns across the rear margin of its bony frill that point downward and outward. It weighed about 2.5 tons and was about 15 feet long.

The horns on both animals range in length from about 6 inches to 1 foot.

Paleontologists say the discovery shows that horned dinosaurs living on the same continent 76 million years ago evolved differently.

Scientists say that other horned dinosaurs lived on the same ancient continent known as Laramidia in what is now Alberta, Canada.

The numerous horns are believed to have been used to attract mates and intimidate sexual competitors, similar to horns on deer.

“The horns really are probably developed at puberty, because most likely these are signals for mate recognition, competition between males, things like that,” Loewen said. “They’re sexual signals and really that’s how we think this group of dinosaurs divided.”

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