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Brown Dwarfs Don't Hang Out With Stars

Brown dwarfs, objects that are less massive than stars but larger than planets, just got more elusive, based on a study of 233 nearby multiple-star systems by NASA's Hubble Space Telescope. Hubble found only two brown dwarfs as companions to normal stars. This means the so-called "brown dwarf desert" (the absence of brown dwarfs around solar-type stars) extends to the smallest stars in the universe.

Sergio Dieterich of Georgia State University in Atlanta and team leader of the study is reporting the results January 6 at the 213th meeting of the American Astronomical Society (AAS) in Long Beach, Calif.
Binary Brown Dwarf Kelu-1 This pair of NASA Hubble Space Telescope images of the binary brown dwarf Kelu-1 trace the orbital motion of the two stars over a seven-year span as photographed by the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) on Hubble. In 1998, the stars were too close together to be resolved by Hubble. By 2005, they had moved apart to a separation of 520 million miles. The projected maximum separation is 550 million miles. Binary systems allow astronomers to estimate the mass of companion objects. The brown dwarfs are 61 and 50 times the mass of Jupiter. They are therefore too small to burn as stars, but too large to have formed as planets. Based on the total estimated mass of the system, astronomers suspect there is a third brown dwarf member that has not yet been resolved.
"We still did not find brown dwarfs around small red stars whose mass is only slightly above the hydrogen burning limit. Especially when we consider the fact that brown dwarfs binaries do exist, the fact that there are very few binaries whose components lie on different sides of the hydrogen burning limit is significant," says Dieterich.

The 233 stars surveyed are part of the RECONS (Research Consortium on Nearby Stars) survey meant to understand the nature of the sun's nearest stellar neighbors, both individually and as a population. The current primary goals are to discover and characterize "missing" members of the sample of stars within 32.6 light-years (10 parsecs) of Earth.


Neanderthals Might Have Made Good Blood Donors

At least two of the extinct, ancient humans had type O blood, making them the "universal donor", according to a new genetic analysis of remains of 45,000 year old individuals.

"If you needed a blood transfusion, you could get it from these Neanderthals," says Carles Lalueza-Fox, a geneticist at Pompeu Fabra University in Barcelona, Spain, who led the study.

That's not to say all Neanderthals were type O - others may have also boasted genes for the A and B blood types, which encode enzymes that sprinkle red blood cells with two different sugar molecules, Lalueza-Fox says.


Dartmouth Researchers Find New Protein Function

A group of Dartmouth researchers has found a new function for one of the proteins involved with chromosome segregation during cell division. Their finding adds to the growing knowledge about the fundamental workings of cells, and contributes to understanding how cell function can go wrong, as it does with cancerous cells.

The researchers studied a protein called NOD, distantly related to the motor proteins that power diverse cellular activities, including intracellular transport, signaling, and cell division. They used X-ray crystallography to determine its structure, and then they used enzyme kinetics to find out how it performed. While this protein is found in fruit flies, the results are helpful in determining how related proteins work in humans.


Immoral advances: Is science out of control?

© Ray Tang/Rex Features
UK protesters demonstrate in a field of genetically modified oilseed rape

What would our forebears have made of test-tube babies, microwave ovens, organ transplants, CCTV and iPhones? Could they have believed that one day people might jet to another continent for a weekend break, meet their future spouse on the internet, have their genome sequenced and live to a private soundtrack from an MP3 player? Science and technology have changed our world dramatically, and, for the most part, we take them in our stride. Nevertheless, there are certain innovations that many people find unpalatable.

Leaving aside special-interest attitudes such as the fundamentalist Christian denial of evolution, many controversies over scientific advances are based on ethical concerns. In the past, the main areas of contention have included nuclear weapons, eugenics and experiments on animals, but in recent years the list of "immoral" research areas has grown exponentially. In particular, reproductive biology and medicine have become ripe for moral outrage: think cloning, designer babies, stem-cell research, human-animal hybrids, and so on. Other troublesome areas include nanotechnology, synthetic biology, genomics and genetically modified organisms or so-called "Frankenfoods".

To many scientists, moral objections to their work are not valid: science, by definition, is morally neutral, so any moral judgement on it simply reflects scientific illiteracy. That, however, is an abdication of responsibility. Some moral reactions are irrational, but if scientists are serious about tackling them - and the bad decisions, harm, suffering and barriers to progress that flow from them - they need to understand a little more and condemn a little less.


Jupiter-like Planets Could Form Around Twin Suns

© Jet Propulsion Laboratory, NASA
Jupiter-like planets could form around twin suns.
Life on a planet ruled by two suns might be a little complicated. Two sunrises, two sunsets. Twice the radiation field.

In a paper published in the December 2008 issue of Astronomy and Astrophysics, astronomer Joel Kastner and his team suggest that planets may easily form around certain types of twin (or "binary") star systems. A disk of molecules discovered orbiting a pair of twin young suns in the constellation Sagittarius strongly suggests that many such binary systems also host planets.

"We think the molecular gas orbiting these two stars almost literally represents 'smoking gun' evidence of recent or possibly ongoing 'giant' (Jupiter-like) planet formation around the binary star system," says Kastner, professor at Rochester Institute of Technology's Chester F. Carlson Center for Imaging Science.


Archaeological Discovery Opens Window To Illyrians

The discovery of an Illyrian trading post gives insight into the ancient peoples of the Balkan Peninsula.

© University of Mostar
Archaeologists found many artefacts, including more than 30 Illyrian boats fully laden with Roman amphorae.
After several weeks of intense digging, an archaeological team from the University of Oslo reported a find last month that could change the written history of Illyrians for a period of their existence.

An Illyrian trading post in the border area between Croatia and Bosnia and Herzegovina (BiH) throws light on an unknown aspect of the life of these ancient people of the Balkan Peninsula.

The head of the archaeological team who discovered the traces of the trading post was Associate Professor Marina Prusac. "Our discovery is important for understanding cultural identities in the Balkans in ancient times," she said.


Mosquitoes Make Sweet Love Music

Amorous mosquitoes "sing" a mating duet by beating their wings together in harmony, US scientists have discovered.

They eavesdropped on a male Aedes aegypti mosquito pursuing a female in mating flight, and recorded the couple's courtship "love song".

The insects spread diseases like yellow fever and dengue, so scientists are seeking ways to control their numbers.

Understanding their mating habits could open up new avenues, says a team from Cornell University, writing in Science.


Mummy Of Female Pharaoh Uncovered

© BBC News
The discovery of such an old mummy is extremely rare, Egyptologists say.
Egyptologists have discovered the remains of a mummy thought to belong to a queen who ruled 4,300 years ago, Egypt's antiquities chief has said.

The body of Queen Seshestet was found in a recently-discovered pyramid in Saqqara, Zahi Hawass announced.

She was mother of King Teti, founder of the Sixth Dynasty of pharaonic Egypt. Her name was not found but "all the signs indicate that she is Seshestet".


Inside the mind of an autistic savant

© Toby Madden/Eyevine
Daniel Tammet

Autistic savant Daniel Tammet shot to fame when he set a European record for the number of digits of pi he recited from memory (22,514). For afters, he learned Icelandic in a week. But unlike many savants, he's able to tell us how he does it. We could all unleash extraordinary mental abilities by getting inside the savant mind, he tells Celeste Biever:

Do you think savants have been misunderstood - and perhaps dehumanised - in the past?

Very often the analogy has been that a savant is like a computer, but what I do is about as far from what a computer does as you can imagine. This distinction hasn't been made before, because savants haven't been able to articulate how their minds work. I am lucky that the autism I have is mild, and that I was born into a large family and had to learn social skills, so I am able to speak up.


A good night out began at home in ancient Greece

© The Bridgeman Art Library / Getty
This red-figure ceramic dish depicts an old man and a young man drinking. It can be seen in the Museum Schloss Hohentubingen, Tubingen, Germany.

It's a wonder the Greeks accomplished as much as they did, as many of their homes seem to have doubled as pubs and brothels. This finding, from new analyses of archaeological remains, could explain why previous hunts for evidence of ancient Greek taverns have been fruitless.

Plays from classical Greece describe lively taverns, but no one has ever unearthed their real-life versions. Clare Kelly Blazeby at the University of Leeds, UK, suspected that archaeologists were missing something, so she took a new look at artefacts from several houses dotted around ancient Greece, dating from 475 to 323 BC.

These had all yielded the remains of numerous drinking cups, and so had been assumed to be wealthy residences. Kelly Blazeby now believes a more likely explanation is that the residents regularly sold wine. Her analysis suggests that many of the houses had hundreds of cups - far too many for a building used only as a residence, she says. Other archaeological artefacts suggest the houses were used for other functions too.

"This blows apart everything that people think about drinking in classical Greece," says Kelly Blazeby, who is presenting her findings on 10 January at the annual meeting of the Archaeological Institute of America in Philadelphia, Pennsylvania. She is not alone. Allison Glazebrook of Brock University in St Catharines, Ontario, Canada, will tell the same conference that some of the houses doubled as brothels. Telltale signs that Glazebrook found include erotic graffiti and objects, and clusters of clay drinking cups.