Science | WPN World People News

• Twenty-six black hole candidates have been identified in Andromeda, aka M31, adding to 9 previously found.
• This is the largest number of possible black holes to date ever found in a galaxy outside of our own Milky Way.
• These are stellar-mass black holes, which are formed by the collapse of a giant star and have masses between five and 10 times the Sun's.
• Researchers used over 150 separate Chandra observations spread over 13 years to obtain these results.

Much like in an old tube television where a beam of electrons moves over a phosphor screen to create images, the new microscopy technique works by scanning a beam of electrons over a sample that has been coated with specially engineered quantum dots. The dots absorb the energy and emit it as visible light that interacts with the sample at close range. The scattered photons are collected using a similarly closely placed photodetector (not depicted), allowing an image to be constructed.

This prototype is the first ever molybdenum based image sensor, 5 times more sensitive than current silicium-based technology.

Transmission electron microscopy (TEM) images of the gold-indium alloy nanoparticles at room temperature. (A) shows an overview of multiple particles, while (D) shows a high-resolution TEM image of one nanoparticle's crystalline gold-indium core surrounded by the amorphous and catalytic oxide shell.

Permafrost zones occupy nearly a quarter of the exposed land area of the Northern Hemisphere. NASA's Carbon in Arctic Reservoirs Vulnerability Experiment is probing deep into the frozen lands above the Arctic Circle in Alaska to measure emissions of the greenhouse gases carbon dioxide and methane from thawing permafrost - signals that may hold a key to Earth's climate future.

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A transmission electron microscopy image of the hybrid material revealing the formation of “titanium dioxide on a stick.”

This image of asteroid 1998 QE2 was obtained on June 1, 2013, when the asteroid was about 3.75 million miles (6 million kilometers) from Earth. The small white dot at upper left is the moon, or satellite, orbiting asteroid 1998 QE2.

This illustration shows the path of the small asteroid 2013 LR6, which will safely pass within 65,000 miles (105,000 kilometers) of Earth on June 7 at 9:42 p.m. PDT (June 8 at 12:42 a.m. EDT).

At each copper atom (grey balls) there is a quadrupole moment. All together, these form a kind of chessboard pattern, whereby the individual squares of the chessboard differ in the orientation of the positively and negatively charged areas (green: positive areas left and right; grey: positive areas top and bottom). At the boundaries between green and grey surfaces, the signs change. Copper atoms close to the boundary have a smaller quadrupole moment than copper atoms in the middle of the areas.

Botany Bay is a topographic saddle exposing sedimentary rocks that are part of the Burns formation, a geological unit Opportunity examined during earlier years of the mission. At Botany Bay, the Burns formation is exposed between isolated remnants of Endeavour Crater's rim. Solander Point and Cape Tribulation are rim segments south of Botany Bay. Opportunity is on the way to Solander Point to spend the upcoming winter season on northerly tilted surfaces. Extensive rock strata are evident on the northern side of Solander Point, and these ancient rocks and surrounding bench materials will be investigated in detail by Opportunity as part of the winter science campaign.