Friday, November 28, 2008

Scientists discover fossil turtle with half a shell

How did the turtle get its shell? The answer is no longer a Just So story. Scientists have unearthed the first fossil found of a turtle at an intermediate stage of evolution, with only half a shell. The ancient creature's belly is fully covered but its back is not. Olivier Rieppel, of the Field Museum in Chicago, said the 220 million-year-old remains - the oldest turtle bones discovered so far - helped solve one of the great mysteries of reptile evolution - the origin of the turtle's protective armour. "The new species shows that the plastron (the lower part of the shell) evolved before the carapace (the upper part)," he said. It also overturned a theory that the turtle's shell had grown out from bony plates on top of the skin, called osteoderms, like those found on crocodiles and some dinosaurs. "This animal tells people to forget about turtle ancestors covered with osteoderms," said Dr Rieppel, a member of the Chinese, American and Canadian team that made the find. Turtles hit on a winning body plan early on. They have looked much as they do today since the time of dinosaurs. And scientists have been debating the origin of their hard, bony shells, which have provided them with shelter and protection, since the 1800s. The new species, Odontochelys semitestacea, has a small, partial shell on its back, extending from its backbone. The well-preserved specimens of three of the ancient turtles also had ribs that had begun to widen, the scientists report in the journal Nature. This supported the theory that the upper shell was an outgrowth of the backbone and ribs.

Dr Rieppel said the fact that ancient creature had a fully formed shell on its underbelly also suggested that the earliest turtles were aquatic animals, rather than land dwellers. This covering would have provided protection from the dangers of predators swimming below it. An Australian expert in ancient reptiles, Benjamin Kear, of La Trobe University in Victoria, said the lower shell might also have acted like a diving belt.


Thursday, November 27, 2008

Hubble finds first ever carbon dioxide on exoplanet

Carbon dioxide, a potential fingerprint of life, has been discovered for the first time in the atmosphere of a planet orbiting another star. However, the planet, HD 189733b, is too hot to be habitable. But the discovery nonetheless has scientists excited, because carbon dioxide is one of four chemicals that life can generate, so being able to detect it shows that astronomers have the ability to find the signs of life on other worlds."This is the first detection of carbon dioxide in the atmosphere of an extrasolar planet, which means that three of the Big Four biomarkers for habitable/inhabited worlds have now been seen: water, methane, and now carbon dioxide," explained Alan Boss, a planet-formation theorist at the Carnegie Institution of Washington who was not involved in the finding. "The only one that has not yet been detected is oxygen/ozone."Boss told that the detections provide "proof of concept" for what astronomers would search for in looking at an Earth-like world. The detection of carbon dioxide, Boss said, was made with a low degree of resolving power, the sort that could be provided by NASA's planned Terrestrial Planet Finder. HD 189733b is about 65 light-years away. It is a giant, gaseous world known as a "hot Jupiter" because it orbits very close to its host star. The finding was made by Giovanna Tinetti from University College London, UK and her colleagues, according to an article in Nature News, an online publication of the journal Nature.

The researchers measured the spectrum of light reflected from the planet's day side by using an interesting trick: They recorded the light of the planet and its star, then recorded it again when the planet was hidden behind the star. The difference revealed what light was coming from the planet, which is otherwise impossible to see as a distinct object because it is overwhelmed by the light of the star.

Wednesday, November 26, 2008

The sacred geometry of planet Earth

The idea that certain geometric shapes possess some kind of power is very old, as is the idea that certain locations on the Earth are sacred or magical. The elites often apply sacred geometry to architecture; America's capital was built in large part with this in mind, and the most recent additions have included the Washington Monument, an obelisk built by the Freemasons, and the Pentagon, commissioned by Freemason Franklin Delano Roosevelt. But, over the years, a number of researchers and writers have suggested that our entire planet contains a magical geometry which governs the location of sacred sites, and that this geometry may be hyper dimensional, and even that the entire universe was constructed in accordance with the laws of hyper dimensional geometry. At the same time, there is a very ancient belief that all of space is filled with an inexhaustible energy, spiritual in origin, called variously chi, ki, prana, kundalini, vril, odic force, or orgone, and that this energy may serve as a dynamic luminiferous aether, and may be the foundation of all other matter and energy. It has been suggested that this energy flows most strongly along certain paths on the Earth's surface, usually called ley lines.

Many years ago, Ivan T. Sanderson suggested that our planet may be attempting to become a crystal. The force of gravity, of course, holds the planet in a roughly spherical shape, but Sanderson suggested that some other force was trying to turn Earth into an enormous crystal, and that certain locations on our planet, regularly spaced, are prone to mysterious vanishings of ships and aircraft, and other paranormal phenomena. Researchers like Carl Munck described a global grid linking ancient sacred sites, and Hugh Harleston Jr. claimed that the ancient ruin of Teotihuacan in Mexico, with its Pyramid of the Sun and Pyramid of the Moon was built according to tetrahedral geometry, and he suspected that the entire universe was constructed according to tetrahedral geometry.

A tetrahedron is one of the five Platonic solids, and it is a three dimensional space bounded by four triangular sides. In a regular tetrahedron the triangles are equilateral, and all of their angles are sixty degrees each. A hexahedron has six sides; a regular hexahedron is a cube. An octahedron has eight sides, a dodecahedron has twelve, and an icosahedron has twenty. The tetrahedron and icosahedron are most germane to this discussion. Buckminster Fuller based his geodesic domes on icosahedrons, which have triangular sides; in a regular icosahedron, as in a regular tetrahedron, the sides are all equilateral triangles.

Bruce Cathie, a former airline pilot from New Zealand, developed some of these ideas into an overall theory. He suggested that the Earth somehow contains or is trying to become a regular icosahedron, and that ancient sacred sites like Stonehenge and Teotihuacan are sited according to a "world grid" based on this. According to his theory major ley lines intersect at or near its vertices, and he believed that ufos travel along the ley lines, which are separated from one another by thirty minutes of arc (one half a degree). Of course, this is counting even the minor ley lines.

In recent years, these ideas have been popularized and further developed by Richard Hoagland. Hoagland pointed out that if a regular tetrahedron of the right size existed witin a sphere like the spinning Earth, and one of its vertices were at the South Pole, the other three vertices would be spaced one hundred and twenty degrees apart some 19.47 degrees (an irrational number, like most constants) north of the equator. He pointed out that major upwellings of energy seem to cluster within a degree or two of one of these locations, like the immense Hawaiian volcanoes on Earth, the Olympus Mons volcano (the highest and most massive mountain in the Solar System) the Great Red Spot on Jupiter, and the Dark Spot on Neptune. These may be north or south of the equator, depending on the planet.

Hoagland also suggested that the current paradigm in physics, based on the twin pillars of relativity theory and quantum mechanics, may be in need of serious revision, and that physics may have been close to a grand unified theory with the original equations of James Clerk Maxwell, before Oliver Heaviside and others simplified and altered them. He believed that much of the energy of the Sun and other stars came not from hydrogen fusion, but from a universal energy from a higher, hypredimensional source, and that this energy also accounted for much of the internal heat of the planets. The energy in stars and planets (and, some of us have noticed, the intensity of their magnetic fields) seems to correlate at least roughly with their angular momentum. Of course, if all of this is true, it may be possible for us to tap this energy and perhaps also to achieve gravity control.

Two mysterious hexagons surround the north pole of the planet Saturn; the main one is 15,000 miles across and, per infrared photos, extends at least sixty miles down into the planet's interior. It does not move with the wind driven clouds, but rotates every ten hours and thirty nine minutes, as do Saturn's radio emissions. This is probably the period of axial rotation. Physicists and astronomers currently have no explanation for any of this.

Hoagland suggested that two four dimensional interlocking hyper tetrahedrons projecting down into three dimensional space could produce such a hexagon. We cannot visualize the fourth dimension, but, reasoning by analogy, we can at least partly understand it. A square is a two dimensional shape bounded by four straight lines, and its three dimensional equivalent is a cube bounded by six squares. So a four dimensional hyper cube would be bounded by six cubes. An equilateral triangle is a two dimensional shape bounded by three straight lines. A tetrahedron is a three dimensional shape bounded by four triangles. So a hyper tetrahedron would be a four dimensional space bounded by five tetrahedrons.

Long ago, a man named Ernst Chladni tried sprinkling sand on a flat metal plate and using sound to vibrate the plate. The sand grains would arrange themselves into geometric shapes, caused by standing waves, and, the higher the frequency became, the more compex the shapes became. The study of this is called cymatics, and some have suggested that this might be the cause of Saturn's hexagon; perhaps this theory and Hoagland's are not mutually exclusive.

Certainly, there is at least some evidence that something strange is going on along lines in the Earth, specifically earthquake faults and the rift zones that separate Earth's tectonic plates. Paranormal phenomena do seem to cluster at such locations, including earthquake lights.

Most of the known early developments of human culture, including the first known civilizations and the development of the major religions happened in or near these zones or (as in the case of Egypt) along earthquake faults parallel to the rifts. Clearly, this needs to be investigated, but we have to remember that the known cultures were almost certainly not the first.

A look at a map or globe of the Earth reveals some interesting oddities. Remember the triangles forming the faces of tetrahedrons and icosahedrons? All but two of Earth's continents are at least roughly triangular. Anyone can see that South America and Africa are roughly triangular. North America is not as obvious, since its shape is interrupted by, among other things, the Florida peninsula. Even Eurasia is at least very roughly triangular, with its shape marred by the Indian subcontinent. In all of these, one apex is more or less to the south, and one side makes up the north of the continent. Another oddity: most of the largest peninsulas on Earth point roughly toward the equator. The exceptions to the triangular continent pattern are Australia and Antarctica. Even if we include Tasmania and New Guinea as part of Australia (which, geologically, under very shallow water, they are) it is still not remotely triangular.

But Antarctica, located around the South Pole, may not be the exception it seems. Earth has no Saturn-style hexagon, perhaps because the Earth has a solid crust and mantle, but both Antarctica and the Arctic Ocean are roughly circular, which is at least fairly close to hexagonal. And the strangeness does not end there. The Arctic Ocean covers 5,400,000 square miles, and Antarctica is only a tiny bit larger, just over 5,400,000 square miles. The greatest depth in the Arctic Ocean is 18,000 feet and the highest point in Antarctica, the Vinson Massif, is only 2,000 feet off at 16,050 feet above sea level. But we don't want to make too much of all this, since Earth's tectonic plates are not triangular, and, anyway, the current arrangement and shape of the continents is only temporary; continental drift has changed it greatly over the aeons.

But maybe there is something very special about the current age...

Sunday, November 23, 2008

The Baghdad Battery


In 1936, while excavating ruins of a 2000-year-old village near Baghdad, workers discovered mysterious small vase. A 6-inch-high pot of bright yellow clay dating back two millennia contained a cylinder of sheet-copper 5 inches by 1.5 inches. The edge of the copper cylinder was soldered with a 60-40 lead-tin alloy comparable to today's solder. The bottom of the cylinder was capped with a crimped-in copper disk and sealed with bitumen or asphalt. Another insulating layer of asphalt sealed the top and also held in place an iron rod suspended into the center of the copper cylinder. The rod showed evidence of having been corroded with an acidic agent.

An Ancient Battery

German archaeologist , Wilhelm Konig, examined the object and came to a surprising conclusion that the clay pot was nothing less than an ancient electric battery.

The ancient battery in the Baghdad Museum

The ancient battery in the Baghdad Museum, as well as those others which were unearthed in Iraq, are all dated from the Parthian occupation between 248 BCE and 226 CE. However, Dr. Konig also found copper vases plated with silver in the Baghdad Museum, excavated from Sumerian sites in southern Iraq, dating back to at least 2500 BCE. When the vases were lightly tapped, a blue patina or film separated from the surface, which is characteristic of silver electroplated onto copper base. It would appear then that the Parthians inherited their batteries from one of the earliest known civilizations.

In 1940, Willard F.M. Gray, an engineer at the General Electric High Volatage Laboratory in Pittsfield, Massachusetts, read of Konig's theory. Using drawings and details supplied by German rocket scientist Willy Ley, Gray made a replica of the battery. Using copper sulfate solution, it generated about half a volt of electricity.

In 1970s, German Egyptologist, Arne Eggebrecht built a replica of the Baghdad battery and filled it with freshly pressed grape juice, as he speculated the
ancients might have done. The replica generated 0.87V. He used current from the battery to electroplate a silver statuette with gold.

This experiment proved that electric batteries were used some 1,800 years before their modern invention by Alessandro Volta in 1799.
It also seems that the use of similar batteries can be safely placed into ancient Egypt, where several objects with traces of electroplated precious metals have been found at different locations. There are several anomalous finds from other regions, which suggests use of electricity on a grander scale.
The Riddle of "Baghdad's batteries"

Arran Frood investigates what could have been the very first batteries and how these important archaeological and technological artefacts are now at risk from the impending war in Iraq.

I don't think anyone can say for sure what they were used for, but they may have been batteries because they do work Dr Marjorie Senechal

War can destroy more than a people, an army or a leader. Culture, tradition and history also lie in the firing line.
Iraq has a rich national heritage. The Garden of Eden and the Tower of Babel are said to have been sited in this ancient land.

In any war, there is a chance that priceless treasures will be lost forever, articles such as the "ancient battery" that resides defenceless in the museum of Baghdad.

For this object suggests that the region, whose civilizations gave us writing and the wheel, may also have invented electric cells - two thousand years before such devices were well known.

Biblical clues

It was in 1938, while working in Khujut Rabu, just outside Baghdad in modern day Iraq, that German archaeologist Wilhelm Konig unearthed a five-inch-long (13 cm) clay jar containing a copper cylinder that encased an iron rod.

Batteries dated to around 200 BC Could have been used in gilding

The vessel showed signs of corrosion, and early tests revealed that an acidic agent, such as vinegar or wine had been present.
In the early 1900s, many European archaeologists were excavating ancient Mesopotamian sites, looking for evidence of Biblical tales like the Tree of Knowledge and Noah's flood.

Konig did not waste his time finding alternative explanations for his discovery. To him, it had to have been a battery.

Though this was hard to explain, and did not sit comfortably with the religious ideology of the time, he published his conclusions. But soon the world was at war, and his discovery was forgotten.

Scientific awareness

More than 60 years after their discovery, the batteries of Baghdad - as there are perhaps a dozen of them - are shrouded in myth.

"The batteries have always attracted interest as curios," says Dr Paul Craddock, a metallurgy expert of the ancient Near East from the British Museum.

"They are a one-off. As far as we know, nobody else has found anything like these. They are odd things; they are one of life's enigmas."

No two accounts of them are the same. Some say the batteries were excavated, others that Konig found them in the basement of the Baghdad Museum when he took over as director. There is no definite figure on how many have been found, and their age is disputed.

Most sources date the batteries to around 200 BC - in the Parthian era, circa 250 BC to AD 225. Skilled warriors, the Parthians were not noted for their scientific achievements.

"Although this collection of objects is usually dated as Parthian, the grounds for this are unclear," says Dr St John Simpson, also from the department of the ancient Near East at the British Museum.

"The pot itself is Sassanian. This discrepancy presumably lies either in a misidentification of the age of the ceramic vessel, or the site at which they were found."

Underlying principles

In the history of the Middle East, the Sassanian period (circa AD 225 - 640) marks the end of the ancient and the beginning of the more scientific medieval era.

Though most archaeologists agree the devices were batteries, there is much conjecture as to how they could have been discovered, and what they were used for.

How could ancient Persian science have grasped the principles of electricity and arrived at this knowledge?

Perhaps they did not. Many inventions are conceived before the underlying principles are properly understood.

The Chinese invented gunpowder long before the principles of combustion were deduced, and the rediscovery of old herbal medicines is now a common occurrence.

You do not always have to understand why something works - just that it does.

Enough zap

It is certain the Baghdad batteries could conduct an electric current because many replicas have been made, including by students of ancient history under the direction of Dr Marjorie Senechal, professor of the history of science and technology, Smith College, US.

"I don't think anyone can say for sure what they were used for, but they may have been batteries because they do work," she says. Replicas can produce voltages from 0.8 to nearly two volts.

Making an electric current requires two metals with different electro potentials and an ion carrying solution, known as an electrolyte, to ferry the electrons between them.
Connected in series, a set of batteries could theoretically produce a much higher voltage, though no wires have ever been found that would prove this had been the case.

"It's a pity we have not found any wires," says Dr Craddock. "It means our interpretation of them could be completely wrong."

But he is sure the objects are batteries and that there could be more of them to discover. "Other examples may exist that lie in museums elsewhere unrecognised".

He says this is especially possible if any items are missing, as the objects only look like batteries when all the pieces are in place.

Possible uses

Some have suggested the batteries may have been used medicinally.

The ancient Greeks wrote of the pain killing effect of electric fish when applied to the soles of the feet.

The Chinese had developed acupuncture by this time, and still use acupuncture combined with an electric current. This may explain the presence of needle-like objects found with some of the batteries.

But this tiny voltage would surely have been ineffective against real pain, considering the well-recorded use of other painkillers in the ancient world like cannabis, opium and wine.

Other scientists believe the batteries were used for electroplating - transferring a thin layer of metal on to another metal surface - a technique still used today and a common classroom experiment.

This idea is appealing because at its core lies the mother of many inventions: money.

In the making of jewellery, for example, a layer of gold or silver is often applied to enhance its beauty in a process called gilding.

Grape electrolyte

Two main techniques of gilding were used at the time and are still in use today: hammering the precious metal into thin strips using brute force, or mixing it with a mercury base which is then pasted over the article.

These techniques are effective, but wasteful compared with the addition of a small but consistent layer of metal by electro-deposition. The ability to mysteriously electroplate gold or silver on to such objects would not only save precious resources and money, but could also win you important friends at court.

Let's hope the world manages to resolve its present problems so people can go and see them. Dr Paul Craddock

A palace, kingdom, or even the sultan's daughter may have been the reward for such knowledge - and motivation to keep it secret.
Testing this idea in the late seventies, Dr Arne Eggebrecht, then director of Roemer and Pelizaeus Museum in Hildesheim, connected many replica Baghdad batteries together using grape juice as an electrolyte, and claimed to have deposited a thin layer of silver on to another surface, just one ten thousandth of a millimetre thick.

Other researchers though, have disputed these results and have been unable to replicate them.

"There does not exist any written documentation of the experiments which took place here in 1978," says Dr Bettina Schmitz, currently a researcher based at the same Roemer and Pelizaeus Museum.

"The experiments weren't even documented by photos, which really is a pity," she says. "I have searched through the archives of this museum and I talked to everyone involved in 1978 with no results."

Tingling idols

Although a larger voltage can be obtained by connecting more than one battery together, it is the ampage which is the real limiting factor, and many doubt whether a high enough power could ever have been obtained, even from tens of Baghdad batteries.

One serious flaw with the electroplating hypothesis is the lack of items from this place and time that have been treated in this way.

"The examples we see from this region and era are conventional gild plating and mercury gilding," says Dr Craddock. "There's never been any untouchable evidence to support the electroplating theory."

He suggests a cluster of the batteries, connected in parallel, may have been hidden inside a metal statue or idol.

He thinks that anyone touching this statue may have received a tiny but noticeable electric shock, something akin to the static discharge that can infect offices, equipment and children's parties.

"I have always suspected you would get tricks done in the temple," says Dr Craddock. "The statue of a god could be wired up and then the priest would ask you questions.

"If you gave the wrong answer, you'd touch the statue and would get a minor shock along with perhaps a small mysterious blue flash of light. Get the answer right, and the trickster or priest could disconnect the batteries and no shock would arrive - the person would then be convinced of the power of the statue, priest and the religion."

Magical rituals

It is said that to the uninitiated, science cannot be distinguished from magic. "In Egypt we know this sort of thing happened with Hero's engine," Dr Craddock says.

Hero's engine was a primitive steam-driven machine, and like the battery of Baghdad, no one is quite sure what it was used for, but are convinced it could work.

If this idol could be found, it would be strong evidence to support the new theory. With the batteries inside, was this object once revered, like the Oracle of Delphi in Greece, and "charged" with godly powers?

Even if the current were insufficient to provide a genuine shock, it may have felt warm, a bizarre tingle to the touch of the unsuspecting finger.

At the very least, it could have just been the container of these articles, to keep their secret safe.

Perhaps it is too early to say the battery has been convincingly demonstrated to be part of a magical ritual. Further examination, including accurate dating, of the batteries' components are needed to really answer this mystery.

No one knows if such an idol or statue that could have hidden the batteries really exists, but perhaps the opportunity to look is not too far away - if the items survive the looming war in the Middle East.

"These objects belong to the successors of the people who made them," says Dr Craddock. "Let's hope the world manages to resolve its present problems so people can go and see them."

Source of the above article: BBC NEWS

New evidence found for Herod's tomb site

Israeli archaeologists excavating what they believe is the tomb of biblical King Herod said Wednesday they have unearthed lavish Roman-style wall paintings of a kind previously unseen in the Middle East and signs of a regal two-story mausoleum, bolstering their conviction that the Jewish monarch was buried here.Ehud Netzer, head of the team from Jerusalem's Hebrew University, which uncovered the site at the king's winter palace in the Judean desert in 2007, said his latest finds show work and funding fit for a king."What we found here, spread all around, are architectural fragments that enable us to restore a monument of 25 meters high, 75 feet high, very elegant, which fits Herod's taste and status," he told The Associated Press in an interview Wednesday at the hillside dig in an Israeli-controlled part of the West Bank, south of Jerusalem.Herod is known for extensive building throughout the Holy Land.Netzer said that since finding fragments of one ornately carved sarcophagus in 2007, he and his team have found two more, suggesting that the monumental tomb may have been a royal family vault."A mausoleum like the one which we have here was generally built by a king but not (necessarily) only for himself, many times for his children and his family, like the famous mausoleum of Augustus in Rome, of Hadrian in Rome," he said. "It's not a surprise that we found here more than one sarcophagus."Herod was the Jewish proxy ruler of the Holy Land under imperial Roman occupation from 37 B.C. and reigned for more than six decades.The ruler is known to have had a taste for extravagance.
Netzer described the winter palace, built on a largely man-made hill 680 meters (2,230 feet) high, as a kind of "country club", with a pool, baths, gardens fed by pools and aqueducts and a 650-seat theater.

In Herod's private box at the auditorium, the diggers discovered delicate frescoes depicting windows opening on to painted landscapes, one of which showed what appeared to be a southern Italian farm, said Roi Porat, one of Netzer's assistants on the digsJust visible in the paintings, dating from between 15-10 B.C., are a dog, bushes and what looks like a country villa.

Friday, November 21, 2008

Ice lake found on the Red Planet

The photographs were taken by the High Resolution Stereo Camera on board Mars Express, the European Space Agency probe which is exploring the planet.
Scientists led by a University of Texas geologist report that data from an unmanned NASA space probe suggests there's much more ice on Mars than previously thought. The Mars Reconnaissance Orbiter, according to an article in the journal Science, has identified several dirt-covered glaciers — including one that is three times longer than the city of Los Angeles and up to a half-mile thick. The glaciers may be remnants of warmer conditions on the Red Planet.

Earlier this year, another spacecraft, NASA's Phoenix Mars Lander, scratched below the dirt-covered plains of the planet's North Pole to uncover a glistening slab of ice. The latest findings, from a team of 11 scientists led by John W. Holt of the University of Texas, will appear in today's edition of Science, a publication of the American Association for the Advancement of Science. Mars is a cold, dry realm. But long channels and what appear to be watersheds in the rugged terrain suggest to some scientists that water once flowed or pooledgnals from the orbiter penetrated the dirt-covered features and were reflected back at velocities con on the planet. In addition, Mars may undergo periodic climate swings linked to changes in its axis. During these changes, the north pole dips, exposing the region to higher temperatures, possibly thawing the ice. The Mars Orbiter used radar to examine the Hellas Basin, an ancient asteroid impact region in the planet's southern hemisphere. The scientists supervising the $700 million project were interested in the area's gently sloping features at the edges of mountains and cliffs. The radar sisistent with radio waves passing through ice, the scientists said.
The spacecraft also spotted similar sloping formations extending from cliffs in the northern hemisphere. If Mars once hosted a more substantial atmosphere and warmer climes, then water may have fostered some form of life. Water would prove valuable to future human explorers as well. Its chemical elements, oxygen and hydrogen, can be used as rocket propellants, and oxygen, of course, is a source of air for breathing.

A giant patch of frozen water has been pictured nestled within an unnamed impact crater on Mars!!!

The ice disc is located on Vastitas Borealis, a broad plain that covers much of Mars' far northern latitudes.
The existence of the water-ice patch on Mars raises the prospect that past or present life will one day be detected.
It also boosts the chances that manned missions could eventually be sent to the Red Planet - because they would probably need accessible water to survive.

Highly visible

The highly visible ice lake is sitting in a crater which is 35 km (23 miles) wide, with a maximum depth of about two km (1.2 miles).
Scientists believe the water-ice is present all year round because the temperature and pressure are not sufficient to allow it to change states.
Researchers studying the images are sure it is not frozen carbon dioxide (CO2), because CO2 ice had already disappeared from the north polar cap at the time the image was taken.
The team has also been able to detect faint traces of water-ice along the rim of the crater and on the crater walls.
Mars is covered with deep gorges, apparently carved out by rivers and glaciers, although most of the water vanished millions of years ago.
Earlier this year, the European Space Agency detected what they called a huge "frozen sea", but it is located below a crust of surface deposits.
Large reserves of water-ice are also known to be held at the poles on Mars, and probably at great depth at many locations around the planet.

Thursday, November 6, 2008

The Chambered Nautilus

The curious-looking chambered nautilus, also known simply as the nautilus, is considered by many to be a living fossil. Nautilus pompilius is the largest and most common of about six species known to exist. Like the coelacanth, it has remained unchanged for over 400 million years. During prehistoric times, there were about 10,000 different species of nautilus, but only a small handful are known to survive today. The nautilus is a mollusk and a member of the cephalopod family. It is closely related to other cephalopods such as the squid, cuttlefish, and octopus. Like most cephalopods, it can use jet propulsion to attain speeds of over two knots. A small tube near the animal's tentacles, known as a siphon, expels water under pressure. This propels the nautilus in the opposite direction at high speeds.
The life and habits of the nautilus are still largely a mystery, since it spends most of its time in deep water. The shell of the nautilus is comprised of many individual chambers. Each chamber is individually sealed and contains an amount of gas. This provides the animal with buoyancy. The nautilus can regulate its density by injecting or removing fluid into these chambers through a system of tubes. This strong shell also provides protection for the animal's soft body. The nautilus has many more tentacles than its close cousins. Depending on the particular species, there can be up to 90 separate tentacles. The tentacles are arranged into two circles, and unlike those of other cephalopods, they have no suction cups. These tentacles are used to catch shrimp, fish and small crustaceans, which the animal crushes with its powerful beak. Nautiluses are active predators, but since their siphon system uses very little energy while swimming, they only need to eat about once a month. Their eyesight is very poor because their eyes contains no lenses. Instead, there is only a tiny hole to allow light into the eye. This system operates much like a pinhole camera. The nautilus is thought to rely mainly on its sense of smell when searching for food or looking for a mate. An adult nautilus can grow to about eight inches (20 centimeters) in length.
The Nautilus reproduces by laying eggs. The eggs are usually attached to rocks in shallow water, hidden away from curious predators. These eggs require between eight and twelve months to fully develop. When a young nautilus first hatches from its egg, it is about an inch in diameter and has a shell with seven chambers. The young animal will drift and feed on plankton and other small prey as it grows. As it gets larger, it will add new chambers to its shell. Each new chamber will be a little larger that the last, allowing the opening of he shell to continually grow larger. The average life span of the nautilus is believed to be about 20 years, which is unusually long for a member of the cephalopod family.

Nautiluses are found throughout the Pacific and Indian oceans, where they spend their daylight hours at depths of about 1,800 feet (550 meters). At night they migrate to shallower waters to feed among the coral reefs. The shell of the nautilus cannot withstand the pressure of depths greater than 2,600 feet (800 meters). Unfortunately, nautilus populations are on the decline due to the harvesting of their beautiful shells. Because of this, export of the shells has been banned in may countries throughout the world. You can help save this amazing animal by refusing to buy nautilus shells.

The Vampire Squid

The vampire squid, known to scientists as Vampyroteuthis infernalis, looks more like something that swam out of a late-night science fiction movie. The squid has large fins at the to of its body that resemble large ears. It is very gelatinous in form, resembling a jellyfish more than the common squid. The vampire squid has the largest eyes relative to its body size of any animal. Though it is relatively small, growing to a length of only about six inches, it has globular eyeballs as large as the eyes of a large dog. The vampire squid's body is covered with light-producing organs called photophores. This gives the squid the unique ability to "turn itself on or off" at will.
When the photophores are off, the squid is completely invisible in the dark waters where it lives. These squid live as deep as 3000 feet. Unlike other squid and octopi, the vampire squid has no ink sack. The squid's arms are covered with sharp tooth-like spikes. This is what gives the animal its unique name. One pair of arms has been modified into retractile filaments that can extend to twice the body length of the animal. The squid may use these arms to capture its prey. When threatened, the squid can draw its arms up over itself and form a defensive web that covers its body. The vampire squid can swim extremely fast for a gelatinous animal. It can reach a speed of 2 body lengths per second and can accelerate to this speed in only 5 seconds. If danger is present, it can make several quick turns in an attempt to escape its enemies. The vampire squid is found throughout the world in most tropical and temperate regions. 

Monday, November 3, 2008


What is Glowing in the Water? Bioluminescent Dinoflagellates

“……it is not the property of fire alone to give light;…small drops of the water, struck off by the motion of the oars in rowing, seem sparkling and luminous.”
Francis Bacon, 1605

What is glowing in the water? If you have visited the ocean and witnessed the water at night, you may be pondering this question. The first scientist to document observations of glowing water was Anixinemenes in the year 500 B.C. He described light emitted by the sea when it was struck with an oar. Light in the ocean has been observed thousands of times since; these “mysterious glowing things” may even be responsible for some of the ghost stories told by sailors who witnessed the glowing waters but did not know the cause. Sightings of aerial bioluminescence have been documented; it appears the sky is glowing. It is assumed that bioluminescent particles are somehow carried into the air from the ocean, but no evidence has been found. Theories as to what is responsible for the things that glow at night have been proposed and many scientists have tried to unravel this mystery. The mystery has not been completely solved, but science is closer to discovering the truth.

Basic Facts of Bioluminescence

Bioluminescence is the light produced by a chemical reaction that occurs in an organism. It occurs at all depths in the ocean, but is most commonly observed at the surface. Bioluminescence is the only source of light in the deep ocean where sunlight does not penetrate. Amazingly, about ninety percent of the organisms that live in the ocean have the capability to produce light.

Four main uses for an organism to bioluminesce have been hypothesized. It can be used to evade predators, attract prey, communcate within their species, or advertise (Nealson, 1985). For example, the angler fish uses the Lure Effect (attracting prey). This fish has a dangling lure in which bioluminescent bacteria live. The lure hangs in front of its mouth; fish swim toward the light and may become food for the angler fish. Some fish use bioluminescence for mating signals or as territorial signals (intraspecies communication), and some use it to communicate interspecies (advertisement). Some organisms employ it for more than a single reason.

Most bioluminescence is blue for two reasons. First, blue-green light travels the farthest in water. Its wavelength is between 440-479 nm, which is mid-range in the spectrum of colors. Second, most organisms are sensitive to only blue light. They do not have the visual pigments to absorb the longer or shorter wavelengths. Red light, which has a long wavelength, is quickly absorbed as you descend in water- this is why underwater pictures appear blue. As with every rule, exceptions exist. Some cnidarians emit green light and one family of fish, the Malacosteids (known as the Loosejaws) emit and are able to see red light. The red light they produce is almost infrared and not visible to the human eye. This is a huge advantage to these fish because they can produce light to see their prey, but their prey can not see them!

Each luminescent organism has a unique flash. Factors that can vary are color, rise time, decay time, and total flash time (Nealson, 1985). Some organisms can emit light continuously, but most emit flashes with varying durations and brightness. The luminescence of one dinoflagellete lasts for 0.1 seconds and is visible to humans. Larger organisms, such as a jellyfish, can luminesce for tens of seconds.
In most multi-cellular organisms, the ability to produce light is controlled neurally. However, the transmitter that signals the change to take place is unknown in most organisms. Luminescence can also be induced by the presence of another luminescing organism.

A few characteristics are common to all bioluminescent reactions. All bioluminescent reactions occur in the presence of oxygen. Two types of chemicals are required- a luciferin and a luciferase (lucifer means light bringing). The luciferin is the basic substrate of the reaction and produces the light. The luciferase catalyzes the reaction. In the basic reaction, the luciferase catalyzes the oxidation of luciferin, which results in two products- light and inactive oxyluciferin. In most organisms, new luciferin must be brought to the system either by diet or internal synthesis for each reaction. Sometimes the luciferin and luciferase are bound together in one unit called a photoprotein. The photoprotein is then triggered when a particular ion is added to the system- frequently calcium. Most of the energy released in this reaction occurs in the form of light, therefore, bioluminescence is commonly called “cold light.”

Five main types of luciferins are known. Bacterial Luciferin is a reduced riboflavin phosphate and found in bacteria, some fish, and squid. Second, Dinoflagellate Luciferin is thought to be derived from chlorophyll because it has similar structure and is found in dinoflagellates and euphasiid shrimp. The third type, Vargulin, is found in the ostracod Vargula and is also used by the midshipman fish Poricthys. This is an interesting dietary link because the fish can not luminesce until they are fed luciferin bearing food. Fourth, Coelenterazine is the most common luciferin; it is found in many phyla- the radiolarians, ctenophores, cnidarians, squids, copepods, chaetognaths, and some fish and shrimp. The fifth is firefly luciferin, which requires ATP as a cofactor in its reactions.


Dinoflagellates are the most common source of bioluminescence and are also known as Pyrrophyta or fire plants. Dinoflagellates are unicellular protists and are usually planktonic- ninety percent are marine plankton. They are small; many are microscopic, although the largest, Noctiluca, is 2 mm in diameter. Dinoflagellates are motile and swim by two flagella, which are movable protein strands. The longitudinal flagella extends from the sulcal groove at the posterior part of the cell and is responsible for the cells forward movement. The flattened flagella extends from the cingulum groove around the equator of the cell and provides the dinoflagellate with the ability to maneuver. Because of these two flagella, the dinoflagellate spirals when it moves.

Dinoflagellates are usually covered by cellulose plates. The cell is surrounded by a series of membranes called the amphiesma. In some, cellulose is deposited between these membranes and forms rigid plates called thecae. When no thecae are present, the dinoflagellates are termed as naked.

Chromosomes are always condensed in dinoflagellates. When the chromosomes of a cell are condensed, the cell is classified as dinokaryotic. The DNA is not associated with the histones as it is in other eukaryotic cells. Dinoflagellates have a relatively large amount of DNA and a large nucleus. The metabolic requirements to support a large amount of DNA probably account for the relatively low growth rates of these protists.

Many dinoflagellates are photosynthetic and play a key role as producers in the food chains of the ocean. The luminescence of photosynthetic dinoflagelletes is very much influenced by the intensity of the previous days sunlight. The brighter the sunlight, the brighter the luminescence will be. Not all are photosynthetic, some are symbiotic- living in the cells of their hosts. Zooxanthallae are the most common symbiotic dinoflagellates and are found in many marine invertebrates such as sponges, corals, jellyfish, flatworms, and other protists. About one half are heterotrophic; they eat other plankton. Sometimes they eat each other by snaring or stinging their prey.

Usually, reproduction is asexual and occurs by the process of mitosis. Occasionally, sexual reproduction can occur when two motile gametes fuse forming a planozygote.
Bioluminescence in Dinoflagellates

Bioluminescence is used to evade predators and acts as a type of burglar alarm defense mechanism in dinoflagellates. Dinoflagelletes produce light when the deformation of the cell by minute forces triggers its luminescence. When the cell is disturbed by a predator, it will give a light flash lasting 0.1 to 0.5 seconds. The flash is meant to attract a secondary predator that will be more likely to attack the predator that is trying to consume the dinoflagellate. The light flash also makes the predator jump and worry about other predators attacking it, making the predator less likely to prey on the dinoflagellate.

In most dinoflagellates, bioluminescence is controlled by an internal biological rhythm. Dinoflagellates are on a circadian rhythm. Towards the end of daylight, luminous chemicals are packaged in vesicles called scintillons. The scintillons then migrate to the cytoplasm from the area around the nucleus. It is not currently known how the scintillons are moved to the cytoplasm. At night, light is triggered by mechanical stimulation. When action potential generates in the vacuole, the action potential propagates throughout the rest of the cell. This allows protons to pass from the vacuole to the cytoplasm (where they were kept). The cytoplasm becomes acidified, normally by hydrogen ions, and the process is activated in the scintillons.

In dinoflagellates, the luciferin is usually bound to a protein called a Luciferin Binding Protein or LBP. At a neutral pH, LBP stabilizes the luciferin from being spontaneously oxidized. When it is activated by a drop in pH, the luciferin dissociates from the LBP and associates with the luciferase. At a pH of 8, the molecule is stable. When the Ph drops to around 6, the luciferin and the LBP dissociate. In the process of being oxidized, luciferin briefly exists in an excited state, after which it decays to the ground state- releasing energy in the form of light. Most dinoflagellates produce much less bioluminescence during the day because there are fewer scintillons. Bioluminescence in dinoflagellates reaches its maximum levels two hours into darkness.