Science & TechnologyS


Telescope

Last Chance to Get a Good Look at Mars Until 2012

Geoff Gaherty
SPACE.com
Thu, 25 Mar 2010 23:11 UTC
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© AFP/USGS/FileA handout image from the US Geological Survey in 2008 shows a mosaic of the Schiaparelli hemisphere of the planet Mars projected into point perspective, a view similar to that which one would see from a spacecraft. A journey from Earth to Mars could eventually take just 39 days, according to a rocket scientist who has the ear of the US space agency.
On Thursday night, March 25, many people may look up at the sky and ask the question, "What's that bright star next to the moon?"

The answer for Thursday night is Mars, but that answer changes night by night as the moon travels along the ecliptic, the path the sun, moon and planets follow across the sky. If you ask the question again on Monday night, March 29, the answer will be the ringed planet Saturn.

Such conjunctions of the moon and planets are regular reminders of how rapidly the moon moves across the sky.

Mars was in opposition to the Sun on Jan. 29, when it appeared 14 arcseconds in diameter, 1/120 of the diameter of the moon. Two months later, it is much farther away, and has shrunk to only 10 arcseconds in diameter.
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Info

Tyrannosaurs Lived in the Southern Hemisphere, Too

Sid Perkins
ScienceNews
Thu, 25 Mar 2010 18:49 UTC
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© R.B.J. Benson/Univ. of CambridgePaleontologists have unearthed the first known fossil of a tyrannosaur that lived on a Southern Hemisphere landmass. This map shows the configuration of landmasses about 110 million years ago (when the human-sized creature lived) and the location of the discovery in Australia.
Paleontologists digging in Australia's aptly named Dinosaur Cove have unearthed the first known fossils of a tyrannosaur from the Southern Hemisphere.

The fossils include the remains of just one 30-centimeter-long bone from the creature's pelvic girdle, but certain features of that bone are seen only in tyrannosaurs, says Roger B.J. Benson and his colleagues report in the March 26 Science. Previously, all known fossils of the tyrannosaur lineage have been unearthed in the Northern Hemisphere.

The size and proportions of the pelvic bone suggest that the dinosaur, which lived around 110 million years ago, was approximately the size of an adult human and tipped the scales at around 80 kilograms. That's around the same size as Raptorex, a tyrannosaur that lived in what is now China at about the same time.
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Book

Random House Fears E-Book Price War on iPad

Dan Hope
TechNewsDaily
Thu, 25 Mar 2010 16:48 UTC
When the iPad was announced, Apple CEO Steve Jobs mentioned five major book publishers that were ready to offer e-books for the iBooks app. What was remarkable about the list was not which companies were on it, but which one was absent, namely Random House, the largest book publisher in the world.

Now the Financial Times is offering an explanation why Random House is reluctant to join iBooks: The company is worried about an upcoming iPad price war.
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Meteor

Flashback Nemesis: Does the Sun Have a 'Companion'?

Robert Roy Britt
Space.com
Thu, 25 Mar 2010 14:43 UTC
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© Space.com
"The trouble with most folks isn't so much their ignorance. It's know'n so many things that ain't so." - A favorite quote of Richard A. Muller, by 19th century humorist Josh Billings.
When you think big, as Richard A. Muller does, you're bound to create ideas now and then that are so compelling you just can't let go of them -- ideas so outlandish that mainstream scientists are equally eager to dismiss them.

Muller, a physicist at University of California at Berkeley, has had his share of big ideas.

If you don't count the restaurant he owned between 1976 and 1982 ("If anyone near and dear to you wants to open a restaurant, I can now be hired to talk them out of it."), Muller's ideas are generally rooted in solid science and genius extrapolation. He's got a gaggle of prestigious awards to prove it, with titles that say things like "outstanding" and "highly original."

But Muller's biggest idea is a real Nemesis. Or so he claims.
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Meteor

Giant Comets, Messengers of Life and Death

William P. Napier
The Cosmic Tusk
Sat, 20 Mar 2010 13:53 UTC
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A Neolithic comet

(Appeared in an anthology: "God, the universe and men - Why do we exist?" (ed. Wabbel, T.D.), Patmos, Dusseldorf, 2003 (original in German).

Comets are jokers in the celestial pack. They irrupt, usually without forewarning, into the orderly progression of the sky. They cross the celestial sphere in weeks or months, growing one or more tails, before fading and disappearing from sight. On rare occasions a comet may be an awesome sight, and the historical literature of the past two thousand years is sprinkled with accounts of the fear induced when a great comet, its smoky red tail bisecting the heavens, appears in the night sky. In the remote past, tales of such apparitions were often conflated with stories of disaster on Earth. A comet called Typhon in Greek mythology was connected with a mythological flood, and the legend of Phaethon, in which the sun's chariot went off course and the Earth was first burned up and then flooded, may describe an exceptional meteorite impact. There is good evidence that the sky in Neolithic times was dominated by a recurrent, giant comet, and that the Earth annually ran through an associated meteor storm of huge intensity. The origin of religion dates to these times and may be tied up with this spectacular night sky. The prospect that cosmic myths, megaliths and art dating from this time may have been responses on the ground to threats in the sky has in recent years moved from Velikovskian fancy to a subject for serious scholarly discussion. In more scientific times, too, it was often suggested that a comet striking the Earth might create create worldwide havoc. For example past encounters of Halley's comet were supposed to have coincided with Noah's flood in 2342 BC.
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Padlock

Laser Security for the Internet: Scientist Invents a Digital Security Tool Good Enough for the CIA -- And for You


Science Daily
Wed, 24 Mar 2010 11:05 UTC
A British computer hacker equipped with a "Dummies" guide recently tapped into the Pentagon. As hackers get smarter, computers get more powerful and national security is put at risk. The same goes for your own personal and financial information transmitted by phone, on the Internet or through bank machines.

Now a new invention developed by Dr. Jacob Scheuer of Tel Aviv University's School of Electrical Engineering promises an information security system that can beat today's hackers -- and the hackers of the future -- with existing fiber optic and computer technology. Transmitting binary lock-and-key information in the form of light pulses, his device ensures that a shared key code can be unlocked by the sender and receiver, and absolutely nobody else. He will present his new findings to peers at the next laser and electro-optics conference this May at the Conference for Lasers and Electro-Optics (CLEO) in San Jose, California.
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Magnify

23,000-Year-Old Stone Wall Found at Entrance to Cave in Greece


Agence France-Presse
Mon, 22 Mar 2010 12:48 UTC
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© AFP/GCM-HOAn undated handout photo provided by the Greek Culture Ministry shows an prehistorical stone wall. The ministry said Greek experts discovered the oldest stony wall of the country, blocking the entrance of a cavern for 23,000 years in Thessalia, in the north.
Athens - The oldest stone wall in Greece, which has stood at the entrance of a cave in Thessaly for the last 23,000 years, has been discovered by palaeontologists, the ministry of culture said Monday.

The age of the find, determined by an optical dating test, singles it out as "probably one of the oldest in the world", according to a ministry press release.

"The dating matches the coldest period of the most recent ice age, indicating that the cavern's paleolithic inhabitants built it to protect themselves from the cold", said the ministry.
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Magnify

Archaeologists: Sublime technique makes Syrian mosaics one of the greatest in the world

H. Sabbagh
Global Arab Network
Wed, 24 Mar 2010 19:29 UTC
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© UnkownHama governorate contains some of the most important mosaics in Syria, with around 50% of uncovered mosaics, most significant of which is "Tiba al-Imam," a 600 square meters mosaic dating back to 242 AD.
Another mosaic housed at Hama National Museum is the "Musicians" mosaic. This piece, measuring 4.25 meters by 5.37 meters, depicts six female musicians and two children, in addition to old musical instrument including an organ, cymbals, two flutes, a harp and an Indian musical instrument consisting of metal bowls placed on a table.

In a statement to Syrian press, Professor of mosaic restoration at Athens University Stephania Chlouveraki underlined the strong composition and accuracy of representation in the Musicians mosaic, noting the small details such as attire, hair, braids, gentle smiles and wide eyes.
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Info

Ancient DNA suggests new hominid line

Bruce Bower
Science News
Wed, 24 Mar 2010 19:19 UTC
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© J. KrauseMitochondrial DNA analysis of a finger bone found in Denisova Cave in the Altai Mountains of southern Siberia suggests that a group of unknown hominids ventured out of Africa less than a million years ago.
A new member of the human evolutionary family has been proposed for the first time based on an ancient genetic sequence, not fossil bones. Even more surprising, this novel and still mysterious hominid, if confirmed, would have lived near Stone Age Neandertals and Homo sapiens.

"It was a shock to find DNA from a new type of ancestor that has not been on our radar screens," says geneticist Svante Pääbo of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. These enigmatic hominids left Africa in a previously unsuspected migration around 1 million years ago, a team led by Pääbo and Max Planck graduate student Johannes Krause reports in a paper published online March 24 in Nature.
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Saturn

Helium Rain on Jupiter

James Riordon
American Physical Society
Wed, 24 Mar 2010 19:13 UTC
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© Hugh F. Wilson and Burkhard Militzer, University of California, BerkeleyThis schematic depiction of the interior of a gas giant (e.g. Jupiter or Saturn) shows Helium-rich droplets forming within the immiscibility layer and raining downwards, leading to a slow increase in the helium concentration in the deep interior. Neon is absorbed in the droplets and carried out of the upper atmosphere.
When NASA's Galileo probe reached Jupiter in 1995 and began sending back data about the gas giant, astronomers were in for a surprise: Jupiter was unusually poor in helium and neon, the two lightest noble gases. New simulations of the physics inside the planet reveal why.

The results, which provide a glimpse into Jupiter's turbulent innards, are reported in the current issue of Physical Review Letters and highlighted with a Viewpoint by Jonathan Fortney (University of California, Santa Cruz) in the March 22 issue of Physics.

To understand how a planet might have formed and what the inside of it might be like, astronomers compare the abundances of its constituent elements with the amounts of those elements found in the sun and meteorites. Jupiter, like the sun, is mostly hydrogen and helium. But the Galileo probe showed that, while it was richer than the sun in six elements, the planet seemed to be missing a small amount of helium and a substantial amount of neon - although neon makes up 1/600 of the mass of the solar system, it made up only 1/6000 of the mass of Jupiter's upper atmosphere, where Galileo made its observations.
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