Science & TechnologyS

Sherlock

Teasing, NASA style: Martian soil may contain toxic compounds harmful to life

Data gathered by NASA's Phoenix lander on Mars have revealed the red planet's soil could contain a toxic substance that would make it less likely that life formed there.

Earlier NASA said Phoenix analyzers detected water in the soil, which suggested that Mars could have the conditions for life. However, if the presence of perchlorate were confirmed, the probability of detecting living organisms there would be reduced.

"The Phoenix team has been waiting for complementary results from the Thermal and Evolved-Gas Analyzer, or TEGA, which also is capable of detecting perchlorate. TEGA is a series of ovens and analyzers that "sniff" vapors released from substances in a sample," NASA said on its website.

Info

Lost world frozen 14m years ago found in Antarctica

A lost world has been found in Antarctica, preserved just the way it was when it was frozen in time some 14 million years ago.

The fossils of plants and animals high in the mountains is an extremely rare find in the continent, one that also gives a glimpse of a what could be there in a century or two as the planet warms.

A team working in an ice-free region has discovered the trove of ancient life in what must have been the last traces of tundra on the interior of the southernmost continent before temperatures began to drop relentlessly.

Meteor

Planets and Perseids should keep stargazers looking up

Meteor shower expected to hit its peak on August 12.

This is a special month for sky watchers to focus on the western sky, with four planets scuttling back and forth in what appears to be a celestial game of tag.

August also means the arrival of bits of debris trailing in the path of comet Swift-Tuttle, which we call the Perseid meteor shower, usually the best of the year.

Sherlock

New life given to ancient Egyptian texts stored at Stanford for decades

They're torn and faded and have the woven texture of a flattened Triscuit. At first glance, the ancient Egyptian texts look like scraps of garbage. And more than 2,000 years ago, that's exactly what they were - discarded documents, useless contracts and unwanted letters that were recycled into material needed to plaster over mummies, like some precursor to papier-mรขchรฉ.

papyri1
©L.A. Cicero
Approximately 70 pieces from Stanford's papyri collection are being analyzed after being kept in storage since the 1920s.

Sherlock

Found: The hottest water on Earth



Image
©NOAA
A black smoker

Even Jules Verne did not foresee this one. Deep down at the very bottom of the Atlantic Ocean, geochemist Andrea Koschinsky has found something truly extraordinary: "It's water," she says, "but not as we know it."

At over 3 kilometres beneath the surface, sitting atop what could be a huge bubble of magma, it's the hottest water ever found on Earth. The fluid is in a "supercritical" state that has never before been seen in nature.

The fluid spews out of two black smokers called Two Boats and Sisters Peak.

Koschinsky, from Jacobs University in Bremen, Germany, says it is somewhere between a gas and a liquid. She thinks it could offer a first glimpse at how essential minerals and nutrients like gold, copper and iron are leached out of the entrails of the Earth and released into the oceans.

Telescope

Asteroid Steins will be tracked by ESA's Rosetta comet chaser

Heading toward its first target-asteroid, (2867) Steins, ESA's Rosetta spacecraft has started using its cameras to visually track the asteroid and eventually determine its orbit with more accuracy.

Image
©ESA

Rosetta started the optical navigation campaign on 4 August 2008, at a distance of about 24 million km from Steins; the campaign will continue until 4 September, when the spacecraft will be approximately 950 000 km from the asteroid.

"The orbit of Steins, with which Rosetta will rendezvous on 5 September, closing to a distance of 800 km, is only known thanks to ground observations, but not yet with the accuracy we would like for the close fly-by," said Gerhard Schwehm, Rosetta Mission Manager based at ESA's European Space Astronomy Centre (ESAC), near Madrid, Spain.

"We will be able to use the first data set for the trajectory correction manoeuvre planned for mid-August."

Light Saber

'Gravity tractor' could deflect asteroids

A "gravity tractor" could deflect an Earth-threatening asteroid if it was deployed when the asteroid was more than one orbit away from the potential impact, according to a new study. If the space rock was found heading straight for Earth, a combination of techniques - including a gravity tractor - might save the day.

Comment: And don't forget to check out Signs of the Times' very own Special Report:

Meteorites, Asteroids, and Comets: Damages, Disasters, Injuries, Deaths, and Very Close Calls


Better Earth

Mexican crater could give clues to ancient Mars

A prehistoric crater left by an asteroid collision in Mexico's Yucatan Peninsula could yield clues about what Mars was like billions of years ago, a NASA scientist says.

Sherlock

UK: Large Roman settlement unearthed by builders



Kinghills dig
©Unknown
Oxford Achaeology's team on the Kingshill site

A huge early Roman settlement unearthed in Cirencester is the most significant historical discovery ever made in the town, archaeologists said this week.

The encampment which covers several hectares, dates back to the late-Iron Age in the 1st century ad, and was likely to have been occupied by the first Roman settlers in Cirencester.

Info

Brightest, Sharpest, Fastest X-ray Holograms Yet

The pinhole camera, a technique known since ancient times, has inspired a futuristic technology for lensless, three-dimensional imaging. Working at both the Advanced Light Source (ALS) at the U.S. Department of Energy's Lawrence Berkeley National Laboratory, and at FLASH, the free-electron laser in Hamburg, Germany, an international group of scientists has produced two of the brightest, sharpest x-ray holograms of microscopic objects ever made, thousands of times more efficiently than previous x-ray-holographic methods.

Image
©DOE/Lawrence Berkeley National Laboratory
A coherent x-ray beam illuminates both the sample and a uniformly redundant array (URA) placed next to it. The CCD detector (whose center is shielded from the direct beam) collects diffracted x-rays from both sample and URA. Processing the resulting interference patterns subsequently yields a hologram.