There was an error in this gadget

Followers

Thursday, October 30, 2008

“Amateur” astronomers capture Jupiter, Charon

The definition of a professional astronomer is one who gets paid to do it. But the difference between that and an amateur, who technically does it for fun, is getting hard to tell.

Take this image of Pluto and its moon Charon taken by so-called amateur astronomers Antonello Medugno and Daniele Gasparri from Italy:


Pluto and Charon from amateurs

The bright blob on the right is Pluto, and Charon is on the left. The separation is 0.7 arcseconds, an incredible feat (the Moon is 2500 times wider than this in the sky). This is definitely Charon; it’s at the correct position, separation, and brightness. They nailed it.

Mind you, Charon wasn’t even discovered until 1978 by a pro, using a 61 inch telescope! The image above was using a 14″ telescope, and is in fact much better than the discovery image. In 30 years of progress, a much smaller commercial telescope can do better than a professional setup could. Wow.

Also, an amateur used an iPhone (and a telescope) to capture this image of Jupiter:


iPhone image of Jupiter

Sure, it’s not the best, but c’mon, it was taken with an iPhone.

We live in the future. Still no flying cars, but we live in the future.

Edited to add: I did not include any of the technical descriptions of the Charon image, and I should have.

Equipment: Meade L200GPS 14″ at f/25, with a Starlight Xpress SXV-H9 CCD
Image scale: 0.15″/pixel, unbinned
Exposure: 6 seconds/frame
Filters: R +Ir (Baader)
Final image: 21 frames, median combined, deconvolved to enhance sharpness

At the time, Pluto was 31 AU away, at a mag of 13.9 and Charon was mag 15.5. The images were taken on August 19, 2008.

Charon image credit: Coelum Astronomia, Daniele Gasparri, and Antonello Medugno

iJupiter credit: Mac Observer.

Tip o’ the dew shield to Davide De Martin and Anthony Bossuyt.

Original here

Electricity Found on Saturn Moon--Could It Spark Life?


Rebecca Carroll
for National Geographic News

Recently identified electrical activity on Saturn's largest moon bolsters arguments that Titan is the kind of place that could harbor life. At a brisk -350 degrees Fahrenheit (-180 Celsius), Titan is currently much too cold to host anything close to life as we know it, scientists say.

But a new study reports faint signs of a natural electric field in Titan's thick cloud cover that are similar to the energy radiated by lightning on Earth.

Lightning is thought to have sparked the chemical reactions that led to the origin of life on our planet.

"As of now, lightning activity has not been observed in Titan's atmosphere," said lead author Juan Antonio Morente of the University of Granada in Spain.

But, he said, the signals that have been detected "are an irrefutable proof for the existence of electric activity."

Frozen, Prebiotic Casserole

Morente's team studied data returned from the European Space Agency's Huygens probe, which broke away from NASA's Cassini spacecraft in 2005 to become the first probe to go below Titan's clouds. (Read "Voyage to Saturn" in National Geographic magazine.)

As soon as the probe entered the moon's atmosphere, a strong wind tilted the device about 30 degrees.

This accidental motion enabled Huygens to detect the Earthlike electrical resonances that it otherwise would have missed, which Morente and colleagues describe their study, published in a recent issue of the journal Icarus.

Jeffrey Bada, of the Scripps Institution of Oceanography, believes the process that allowed lightning to spark life on Earth is universal and could happen in many environments—including on Titan.

Confirmation earlier this year of Titan's hydrocarbon lakes makes the Saturnian moon the first place other than Earth where open bodies of liquid have been found.

Hydrocarbons are organic molecules, and the fact that they exist in large quantities on Titan suggests that life could take root there under the right conditions. "If you had lightning taking place in the atmosphere of Titan, you could make what we call precursor molecules," said Bada, who was not involved with Morente's study.

"To go any further than that," he said, "you need liquid water."

Titan's water is currently frozen into chunks as hard as granite. If those ice "rocks" were to melt, however, the environment could become more hospitable to the building blocks of life.

With liquid water, the planet could host the formation of amino acids and then full proteins, which drive all biochemistry and set the stage for more complex molecules.

"I look at Titan as a big, frozen, prebiotic casserole," Bada said, referring to the state before the emergence of life.

"The idea that life could be widespread in the universe, I think, is very credible."

A Field of Its Own

Advocates of theories about life on Titan note that various celestial events could temporarily warm up the moon enough to melt its ice into water.

Perhaps this happened in the past, they say—or it could happen in the future.

But study author Morente said it's impossible to precisely assess such possibilities with the scientific knowledge available today.

What astronomers do know is that Titan does not have its own magnetic field, he said. The moon instead orbits within Saturn's magnetosphere at differing distances from the planet.

This means that the strength of Titan's magnetic field is constantly changing, leaving its surface more vulnerable to damaging cosmic rays.

Without stable protection from radiation, Morente said, "the existence of life is very unlikely."

Original here

Ice: the Cradle of Life?

Ice Bubbles

Image: Jim’s outside photos

It is one of the most sought after answers in modern science: where did life come from? How did those first molecules put themselves together in such a way as to form molecular machinery capable of reproducing itself and thereby fueling the creation of the vast and amazing diversity we see on this planet today? Up until recently it was assumed that life first arose on this planet, and on any other where it might exist, in water. It’s a very sensible assumption. Water is critical to all forms of life and almost all the biological functioning that we know of would be impossible without it. But what if we were looking at the wrong type of water, what if life arose in solid ice?

This counterintuitive hypothesis has a small but growing representation in the scientific community. The notion that life may have formed in ice instead of liquid water is significant in that there is ice almost everywhere in the solar system, while water seems to be rare. Lots of planets and many of their moons have plenty of observable ice, and if solid H2O proves to be the most hospitable place for the formation of the precursors to modern life then our chances of encountering biology of some form or another somewhere else in our solar system increase significantly.

icicles

Image: justmakeit

To understand this theory we need to go back to basic chemistry. Solid water - ice - can be compared to a highly polished military unit on parade review, all the H2O molecules know exactly where and how to stand in relation to each other and they do their best not deviate from that pattern. Now imagine injecting impurities (say a bunch of drunks and anarchists) into that regiment of soldiers at attention; the drunks are probably going to have a hard time fitting in.

The sots and anarchists in this analogy are a mix of metals and organics and basically any molecule that isn’t good old H2O. What happens, in both ice and imaginary military units analogous to ice, is that all the impurities end up slowly trudging through the ranks until they run into other impurities. Eventually all of the interesting oddball molecules are forced together into millions of little pockets; this even causes some of the surrounding solid H2O to break ranks and turn into liquid water. What you then end up with is essentially millions of discrete test tubes surrounded by solid ice, stuffed chock full of every interesting atom in the vicinity. The close confines then constantly force the molecules to run into (react) with one another in ways not really possible in any other natural setting. On top of that you even have a supply of liquid water. Sounds like the perfect recipe for organic life if there ever was one.

alien

Image: concertayouch

So far there have only been a few laboratory experiments testing the foundations of this hypothesis, but the results have been encouraging. While it will likely be a very long time before anybody figures out exactly how life first arose, if solid ice is where it first happened, alien life might be much closer than we think.

Original here

T.rex 'followed its nose' while hunting

Tyrannosaurus rex a theropod from the Late Cretaceous of North America pencil drawing. Image: Wikipedia.
Tyrannosaurus rex, a theropod from the Late Cretaceous of North America, pencil drawing. Image: Wikipedia.

Although we know quite a bit about the lifestyle of dinosaur; where they lived, what they ate, how they walked, not much was known about their sense of smell, until now.

Scientists at the University of Calgary and the Royal Tyrrell Museum are providing new insight into the sense of smell of carnivorous dinosaurs and primitive birds in a research paper published in the British journal Proceedings of the Royal Society B.

The study, by U of C paleontologist Darla Zelenitsky and Royal Tyrrell Museum curator of dinosaur palaeoecology François Therrien, is the first time that the sense of smell has been evaluated in prehistoric meat-eating dinosaurs. They found that Tyrannosaurus rex had the best nose of all meat-eating dinosaurs, and their results tone down the reputation of T. rex as a scavenger.

The researchers looked at the importance of the sense of smell among various meat-eating dinosaurs, also called theropods, based on the size of their olfactory bulbs, the part of the brain associated with the sense of smell. Although the brains of dinosaurs are not preserved, the impressions they left on skull bones or the space they occupied in the skull reveals the size and shape of the different parts of the brain. Zelenitsky and Therrien CT-scanned and measured the skulls of a wide variety of theropod dinosaurs, including raptors and ostrich-like dinosaurs, as well as the primitive bird Archaeopteryx.

"T. rex has previously been accused of being a scavenger due to its keen sniffer, although its nose may point to alternative lifestyles based on what we see in living animals" says Zelenitsky, the lead investigator on the study. "Large olfactory bulbs are found in living birds and mammals that rely heavily on smell to find meat, in animals that are active at night, and in those animals that patrol large areas. Although the king of carnivorous dinosaurs wouldn't have passed on scavenging a free dead meal, it may have used its sense of smell to strike at night or to navigate through large territories to find its next victim."
In addition to providing clues about the biology and behavior of the ancient predators, the study also reveals some surprising information about the sense of smell in the ancestors of modern birds.

Therrien and Zelenitsky found that the extinct bird Archaeopteryx, known to have evolved from small meat-eating dinosaurs, had an olfactory bulb size comparable to most theropod dinosaurs. Although sight is very good in most birds today, their sense of smell is usually poor, a pattern that does not hold true in the ancestry of living birds.

"Our results tell us that the sense of smell in early birds was not inferior to that of meat-eating dinosaurs," says Therrien. "Although it had been previously suggested that smell had become less important than eye sight in the ancestors of birds, we have shown that this wasn't so. The primitive bird Archaeopteryx had a sense of smell comparable to meat-eating dinosaurs, while at the same time it had very good eye sight. The sense of smell must have become less important at some point during the evolution of those birds more advanced than Archaeopteryx."

Original here

Nanoparticles Target Multiple Cancer Genes, Shrink Tumors More Effectively

“It is a very selective and targeted approach,” said Gavin Robertson, Ph.D., who led the team of researchers from the Penn State College of Medicine. “And unlike most other cancer drugs that inadvertently affect a bunch of proteins, we are able to knock out single genes.”
The Penn State researchers speculated that siRNA could turn off the two cancer-causing genes and potentially treat the deadly disease more effectively. “siRNA checks the expression of the two genes, which then lowers the abnormal levels of the cancer causing proteins in cells,” explained Dr. Robertson. This research appears in the journal Cancer Research.

In recent years, researchers have zeroed in on two key genes—B-Raf and Akt3—that play key roles in the development of melanoma. Mutations in the B-Raf gene, the most frequently mutated gene in melanoma, lead to the production of a mutant form of the B-Raf protein, which then helps mole cells survive and grow. B-Raf mutations alone, however, do not trigger melanoma development. That event requires a second protein, called Akt3, that regulates the activity of the mutated B-Raf, which aids the development of melanoma. The siRNA agents used in this study specifically target Akt3 and the mutant B-Raf and therefore do not affect normal cells.

However, although knocking out specific genes may seem like a straightforward task, delivering the siRNA drug to cancerous cells is another story, because not only do protective layers in the skin keep drugs out but also chemicals in the skin quickly degrade the siRNA. To clear these two hurdles, Dr. Robertson and his team engineered lipid-based nanoparticles that can incorporate siRNA into their hollow interiors. The researchers then used a portable ultrasound device to temporarily create microscopic holes in the surface of the skin, allowing the drug-filled particles to leak into tumor cells beneath.

When the researchers exposed lab-generated skin containing early cancerous lesions to the treatment 10 days after the skin was created, the siRNA reduced the ability of cells containing the mutant B-Raf to multiply by nearly 60 to 70 percent and more than halved the size of lesions after 3 weeks. “This is essentially human skin with human melanoma cells, which provides an accurate picture of how the drug is acting,” said Dr. Robertson.

Mice with melanoma that underwent the same treatment had their tumors shrink by nearly 30 percent when only the mutant B-Raf was targeted. There was no difference in the development of melanoma when the Akt3 gene alone was targeted, although existing tumors shrank by about 10 to 15 percent in 2 weeks. However, when the researchers targeted both Akt3 and mutant B-Raf at the same time, they found that tumors in the mice shrank about 60 to 70 percent more than when either gene was targeted alone.

“If you knock down each of these two genes separately, you are able to reduce tumor development somewhat,” Dr. Robertson said. “But knocking them down together leads to synergistic reduction of tumor development.”

This work, which was supported in part by the National Cancer Institute, was detailed in the paper “Targeting V600EB-Raf and Akt3 Using Nanoliposomal-Small Interfering RNA Inhibits Cutaneous Melanocytic Lesion Development.” An abstract of this paper is available at the journal’s Web site (http://dx.doi.org/doi:10.1158/0008-5472.CAN-07-6614).

Provided by National Cancer Institute

Original here

Pipeline bursts at Alaska's Prudhoe Bay

BP's old bugaboo, corrosion, might have struck again in the giant Prudhoe Bay oil field.

The oil company suspects corrosion contributed to a pressurized natural gas pipeline blowing apart on Sept. 29, BP spokesman Steve Rinehart said.

No one was hurt, though some workers were in the vicinity when the line ruptured violently, hurling a length of pipe across the tundra.

Automated safety systems and field workers rushed to shut down the pipeline, which was 8 inches in diameter and carried gas for shooting underground, part of a technique to help coax out additional crude oil.

The incident forced the shutdown of two well pads producing about 5,000 barrels of oil per day -- less than 1 percent of total North Slope oil output. The pads remained out of service on Friday.

BP will do a metallurgical analysis of the failed pipe before declaring corrosion as the culprit for the rupture, Rinehart said. Some possibilities have been ruled out, he said, such as a bad weld.

Investigators found the corrosion had attacked the outside surface of the above-ground pipe at a point where insulation that normally jackets the line was missing, Rinehart said.

Moisture had wicked beneath the exposed insulation and come into contact with the steel, causing corrosion that can eat through metal and weaken a pipeline, he said.

As a safety measure, BP workers will look for any pipes that might be in a similar condition, Rinehart said.

State and federal pipeline regulators are investigating the pipeline rupture.

BP runs Prudhoe, the nation's largest oil field, on behalf of itself and other owners including Conoco Phillips and Exxon Mobil.

Corrosion has bedeviled BP since 2006, when oil leaks from major Prudhoe pipelines drew intense regulatory and congressional scrutiny of the London-based company. The lines were found to be riddled with corrosion.

Original here