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<p>This map of dark matter in the Universe was obtained from data from the KiDS survey, using the VLT Survey Telescope at ESO’s Paranal Observatory in Chile. It reveals an expansive web of dense (light) and empty (dark) regions. This image is one out of five patches of the sky observed by KiDS. Here the invisible dark matter is seen rendered in pink, covering an area of sky around 420 times the size of the full moon. This image reconstruction was made by analysing the light collected from over three million distant galaxies more than 6 billion light-years away. The observed galaxy images were warped by the gravitational pull of dark matter as the light travelled through the Universe.</p>

<p>Some small dark regions, with sharp boundaries, appear in this image. They are the locations of bright stars and other nearby objects that get in the way of the observations of more distant galaxies and are hence masked out in these maps as no weak-lensing signal can be measured in these areas.</p>

<p>Credit:</p>

<p>Kilo-Degree Survey Collaboration/H. Hildebrandt & B. Giblin/ESO</p>
Dark Matter May be Smoother than Expected
Analysis of a giant new galaxy survey suggests that dark matter may be less dense and more smoothly distributed throughout space than previously thought.
<p>Interference pattern created by neutron holography.</p>

<p>Credit:</p>

<p>NIST</p>
Holograms from Neutrons Created
For the first time, scientists have used neutron beams to create holograms of large solid objects, revealing details about their interiors in ways that ordinary laser light-based visual holograms cannot.

<p>An artist’s conception of this unusual system, courtesy of Jonathan Holden/Disk Detective.</p>
Oldest Known Planet-Forming Disk Found
Scientists find a star surrounded by the oldest known circumstellar disk—a primordial ring of gas and dust that orbits around a young star and from which planets can form.
<p>Mars’ Valles Marineris canyon, pictured, spans as much as 600 kilometers across and delves as much as 8 kilometers deep. The image was created from over 100 images of Mars taken by Viking Orbiters in the 1970s.</p>

<p>Image: NASA</p>
New Technique May Help Detect Martian Life
A novel interpretation of Raman spectra will help the 2020 Mars rover select rocks to study for signs of life.


Stable Propagation of Light in Nano-Photonic Fibers
New model on how to achieve a more stable propagation of light for future optical technologies was published.
Quantum Effects Observed in ‘One-Dimensional’ Wires
Researchers have observed quantum effects in electrons by squeezing them into one-dimensional ‘quantum wires’ and observing the interactions between them.
Echoes of Black Holes Eating Stars Found
Astronomers now have new insights into tidal disruption flares, thanks to data from NASA's Wide-field Infrared Survey Explorer (WISE).

Science Facts

Large Asteroid Zooms Safely Past Earth

by NASA Headquarters and ScienceIQ.com

An artist A mountain-sized asteroid made its closest approach to Earth at 9:35 a.m. Eastern Time on Wednesday, Sept. 29, 2004. Although asteroid 4179 Toutatis came no closer than four times the distance between Earth and the Moon (approximately 1.5 million kilometers or 961,000 miles), this is the closest approach of any known asteroid of comparable size this century. 'This is the closest Toutatis will come for another 500 years, and its orbit is very well known,' said Dr. Don Yeomans of NASA's Jet Propulsion Laboratory, Pasadena, Calif., manager of NASA's Near Earth Objects Program Office. 'What this fly-by provides is an opportunity to study one of our closest solar system neighbors.'

'While we have done radar observations on this particular asteroid before, this is the closest it has come since at least the twelfth century,' said Dr. Steve Ostro, a scientist at JPL. 'We will use the huge dish in Arecibo, Puerto Rico, to refine our knowledge of its physical characteristics and its trajectory.' Named after an obscure Celtic and Gallic god, Toutatis is a yam-shaped space rock that measures 1.92 kilometers (1.2 miles) by 2.29 kilometers (1.4 miles) by 4.6 kilometers (2.9 miles). Toutatis has one of the strangest rotation states observed in the solar system. Instead of spinning around a single axis, as do the planets and the vast majority of asteroids, it 'tumbles' somewhat like a football after a botched pass. Its rotation is the result of two different types of motion with periods of 5.4 and 7.3 Earth days, which combine in such a way that Toutatis's orientation, with respect to the solar system, never repeats.

When the asteroid flew past Earth, it was traveling at approximately 39,600 kilometers per hour (24,550 miles per hour). Toutatis will not be this close again until 2562. It was discovered in 1989.



When Do We Encounter Ionizing Radiation In Our Daily Lives?

Everyone who lives on this planet is constantly exposed to naturally occurring ionizing radiation (background radiation). This has been true since the dawn of time. The average effective dose equivale ...
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WMAP
The Wilkinson Microwave Anisotropy Probe (WMAP)

The cosmic microwave background (CMB) radiation is the radiant heat left over from the Big Bang. It was first observed in 1965 by Arno Penzias and Robert Wilson at the Bell Telephone Laboratories in M ...
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A speck from a comet? Displayed in a close-up under an electron microscope, this tiny bit ofcosmic dust may be our first sample of a passing comet. Less than one-tenth of a millimeter across, the particle is composed of millions ofeven tinier crystals.
It's Dusty Out There

There is no lower limit to the size of the solid particles that move around the Sun. Small asteroids grade downward into large meteoroids and then into smaller pebbles and so on down to the tiniest pa ...
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Science Quote

'The important thing is not to stop questioning. Curiosity has its own reason for existing. Never lose a holy curiosity.'

Albert Einstein
(1879-1955)


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