Category Astronomy/Space

New approach to search for Life in Alpha Centauri: Polarimetric Signatures of Photosynthetic Pigments as Biomarkers.

The polarized light reflected from the leaf contains a footprint of the leaf's biopigments. These biosignatures can be detected with a polarization filter, shown here as a pair of sunglasses. Credit: Illustration: Svetlana Berdyugina

The polarized light reflected from the leaf contains a footprint of the leaf’s biopigments. These biosignatures can be detected with a polarization filter, shown here as a pair of sunglasses. Credit: Illustration: Svetlana Berdyugina

Biopigments of plants, so-called biological photosynthetic pigments, leave behind unique traces in the light they reflect, an international team has discovered. The scientists studied these biosignatures with the help of polarization filters: If biopigments were present as a sign of life on a planet, they would leave behind a detectable polarized signature in the reflected light.

Eg Chlorophyll pigments in plant leaves, absorb blue to red light but reflect a small part of green in the visible spectrum and thus appear green...

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Lightning Strike can Reshape a Mineral’s Crystal Structure:

A rock fulgurite revealed that lightning strikes alter quartz's crystal structure on the atomic level.

A rock fulgurite revealed that lightning strikes alter quartz’s crystal structure on the atomic level.

Researchers once believed only meteorites could do so. At a rock outcropping in southern France, a jagged fracture runs along the granite. The surface in and around the crevice is discolored black, as if wet or covered in algae. But the real explanation for the rock’s unusual features is more dramatic: a powerful bolt of lightning.

Using extremely high-resolution microscopy, Prof Gieré et al found that not only had the lightning melted the rock’s surface, resulting in a distinctive black “glaze,” but had transferred enough pressure to deform a thin layer of quartz crystals beneath the surface, resulting in distinct atomic-level structures called shock lamellae...

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Physicists have revealed a new understanding of Nucleosynthesis in Stars, via radioactive Al

 

>>providing insight into the role massive stars play in the evolution of the Milky Way and the origins of the Solar System. Radioactive aluminium (aluminium-26, or Al26) is an element that emits gamma radiation through its decay enabling astronomers to image its location in our galaxy. Studying how Al26 is created in massive stars, scientists have distinguished between previously conflicting assumptions about its rate of production by nuclear fusion.

Scientists measured the fusion of helium and sodium at 2 separate particle accelerators in Canada and Denmark, and the rate of production of Al26 was determined to within a factor of 2...

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New Horizons Discovers Flowing Ices on Pluto

 In the northern region of Pluto’s Sputnik Planum, swirl-shaped patterns of light and dark suggest that a surface layer of exotic ices has flowed around obstacles and into depressions, much like glaciers on Earth. Credits: NASA/JHUAPL/SwRI

In the northern region of Pluto’s Sputnik Planum, swirl-shaped patterns of light and dark suggest that a surface layer of exotic ices has flowed around obstacles and into depressions, much like glaciers on Earth. Credits: NASA/JHUAPL/SwRI

NASA’s New Horizons mission has found evidence of exotic ices flowing across Pluto’s surface, at the left edge of its bright heart-shaped area. New close-up images from the spacecraft’s Long-Range Reconnaissance Imager (LORRI) reveal signs of recent geologic activity, something scientists hoped to find but didn’t expect. “We’ve only seen surfaces like this on active worlds like Earth and Mars,” said mission co-investigator John Spencer of SwRI.

The new close-up images show fascinating detail within the Texas-sized plain (Sputnik Planum) ...

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