Science & TechnologyS

Telescope

Stars Forming Just Beyond Black Hole's Grasp At Galactic Center

young, blue stars encircling a supermassive black hole
© NASA, ESA, and A. Schaller (for STScI)This artist's concept shows young, blue stars encircling a supermassive black hole at the core of a spiral galaxy like the Milky Way. The background stars are the typical older, redder population of stars that inhabit the cores of most galaxies (including our own). CfA astronomers caught two stars in the act of forming within a few light-years of the Milky Way's center. Their find demonstrates that stars can form at our galaxy's core despite the powerful gravitational tides generated by the black hole.
The center of the Milky Way presents astronomers with a paradox: it holds young stars, but no one is sure how those stars got there. The galactic center is wracked with powerful gravitational tides stirred by a 4 million solar-mass black hole. Those tides should rip apart molecular clouds that act as stellar nurseries, preventing stars from forming in place. Yet the alternative - stars falling inward after forming elsewhere - should be a rare occurrence.

Using the Very Large Array of radio telescopes, astronomers from the Harvard-Smithsonian Center for Astrophysics and the Max Planck Institute for Radio Astronomy have identified two protostars located only a few light-years from the galactic center. Their discovery shows that stars can, in fact, form very close to the Milky Way's central black hole.

"We literally caught these stars in the act of forming," said Smithsonian astronomer Elizabeth Humphreys. She presented the finding today at a meeting of the American Astronomical Society in Long Beach, Calif.

Info

Mystery Of South American Trophy Heads Solved

Nasca trophy head
© Field MuseumNasca trophy head from a tomb at the site of Cahuachi.
The mystery of why ancient South American peoples who created the mysterious Nazca Lines also collected human heads as trophies has long puzzled scholars who theorize the heads may have been used in fertility rites, taken from enemies in battle or associated with ancestor veneration.

A recent study using specimens from Chicago's Field Museum throws new light on the matter by establishing that trophy heads came from people who lived in the same place and were part of the same culture as those who collected them. These people lived 2,000 to 1,500 years ago.

Archaeologists determined that the severed heads were trophies because holes were made in the skulls allowing the heads to be suspended from woven cords. A debate has been raging for the past 100 years over their meaning.

Telescope

Astronomers To Gaze Back In Time And Map History Of Universe

Milky Way galaxy seen at 100 microns
© NASA/JPL-CaltechArtist's view of Spitzer seen against the infrared sky. The band of light is the glowing dust emission from the Milky Way galaxy seen at 100 microns (as seen by the IRAS/COBE missions).
UK astronomers are set to expand our knowledge of the history of our Universe with a new project to map the inception and formation of galaxies.

Making use of an Infrared Array Camera on NASA's Spitzer Space Telescope, the Spitzer Extragalactic Representative Volume Survey (SERVS) will make a very large map of the sky, capable of detecting extremely faint galaxies. The primary aim is to chart the distribution of stars and black holes from when the Universe was less than a billion years old to the present day.

The survey is one of the largest ever awards of observing time on a space-based observatory - a total of 1400 hours.

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Gene expression and splicing vary widely from one tissue to the next

Genes talk to themselves and to each other to control how a given cell manufactures proteins. But variation in the control of the same gene in two different tissues may contribute to certain human traits, including the likelihood of getting a disease, said a team of geneticists and neuroscientists at Duke University Medical Center.

Using a genome-wide screen to look for single-nucleotide changes, the researchers found that the expression of a given gene -- the amount of protein it is producing -- can vary widely. They also found that genetic variation leading to alternative splicing, a process that can create different proteins from the same gene, might in general be more relevant to disease than the effects of genetic variation on the general amount of gene expression.

Coffee

Stonehenge had special resonant acoustic properties

Image
© Getty Images An academic from Huddersfield University believes the standing stones had the right acoustics to amplify certain sounds
The monument has baffled archaeologists who have argued for decades over the stone circle's 5,000-year history but academic Rupert Till believes he has solved the riddle by suggesting it may have been used for ancient raves.

Mr Till, an expert in acoustics and music technology at Huddersfield University, West Yorks., believes the standing stones had the ideal acoustics to amplify a "repetitive trance rhythm".

The original Stonehenge probably had a "very pleasant, almost concert-like acoustic" that our ancestors slowly perfected over many generations

Telescope

Milky Way a Swifter Spinner, More Massive, New Measurements Show

Fasten your seat belts -- we're faster, heavier, and more likely to collide than we thought. Astronomers making high-precision measurements of the Milky Way say our Galaxy is rotating about 100,000 miles per hour faster than previously understood.

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Baby Jupiters Must Gain Weight Fast

Baby Jupiters
© NASAThis photograph from NASA's Spitzer Space Telescope shows the young star cluster NGC 2362. By studying it, astronomers found that gas giant planet formation happens very rapidly and efficiently, within less than 5 million years, meaning that Jupiter-like worlds experience a growth spurt in their infancy.
The planet Jupiter gained weight in a hurry during its infancy. It had to, since the material from which it formed probably disappeared in just a few million years, according to a new study of planet formation around young stars.

Smithsonian astronomers examined the 5 million-year-old star cluster NGC 2362 with NASA's Spitzer Space Telescope, which can detect the signatures of actively forming planets in infrared light. They found that all stars with the mass of the Sun or greater have lost their protoplanetary (planet-forming) disks. Only a few stars less massive than the Sun retain their protoplanetary disks. These disks provide the raw material for forming gas giants like Jupiter. Therefore, gas giants have to form in less than 5 million years or they probably won't form at all.

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The 'first true scientist'

For, without doubt, another great physicist, who is worthy of ranking up alongside Newton, is an Iraqi scientist born in AD 965 who went by the name of al-Hassan Ibn al-Haytham.
BBC Arab Physicist
© BBC NewsAn artist's impression of al-Hassan Ibn al-Haytham

Most people in the West will never have even heard of him.

As a physicist myself, I am quite in awe of this man's contribution to my field, but I was fortunate enough to have recently been given the opportunity to dig a little into his life and work through my recent filming of a three-part BBC Four series on medieval Islamic scientists.


Yet, the truth is rather grayer; and I feel it important to point out that, certainly in the field of optics, Newton himself stood on the shoulders of a giant who lived 700 years earlier.

It is incredible that we are only now uncovering the debt that today's physicists owe to an Arab who lived 1,000 years ago

R2-D2

Will brain waves help pilot future space ships?

NASA's plans to ship people to the moon and some day Mars are very much up in the air these days, with debate over Barack Obama's plans for the space agency a hot water cooler topic in the aerospace industry. Budget battles aside, one new study asks, how should these future astronauts steer their way around our solar system?

Brain waves, suggests the current Acta Astronautica journal report. Fans of Neuromancer may recall the story's hero using brain implants to navigate around cyberspace, but the researchers led by Carlo Menon of the European Space Agency, see astronaut brain-machine interfaces as a the way to get around outer space.

Telescope

Mystery stone circles may point to water on Mars

Elysium Planitia
© NASA/JPLElysium Planitia
Stone circles on Mars are prompting a rethink about the planet's ancient climate.

Using cameras on NASA's Mars Reconnaissance Orbiter, Matt Balme of the Open University in Milton Keynes, UK, and his colleagues mapped the Elysium Planitia, a region near the equator. They saw rings up to 23 metres across made up of stones sorted by size into concentric bands.

On Earth, similar structures form via repeated freezing and thawing of ice, but with the stones sorted into layers. Water in soil under stones freezes faster than in surrounding soil, and the expanding ice pushes the stones upwards. Larger stones rise faster, and so layers sorted by size form.