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<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.
<p>Simplification to represent PT (Parity-Time) symmetry. Imagine a situation where two cars are traveling at the same speed at some instant in time, but car A is speeding up, and car B is slowing down. In order to go at the same speed, you can jump from one car to the other (Parity reversal) and back in time (Time reversal). The cars are like the light waves inside the fiber, the speed of the cars is a representation of the intensity of light and the jump symbolizes a phenomenon called tunneling. (Graphics modified from freepiks).</p>
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).
Individual Atoms Behavior Observed
For first time, researchers see individual atoms keep away from each other or bunch up as pairs.

Science Facts

Introduction to Constellations

by Gene Mascoli and ScienceIQ.com

Constellation Sagittarius.: Image Courtesy Chandra 'Constellation' is the name we give to seeming patterns of starsin the night sky. 'Stella' is the Latin word for star and a constellation is a grouping of stars. In general, the stars in these groups are not actually close to each other in space, they just appear to be close when viewed from Earth. If we could travel by spaceship to another part of the galaxy, we would imagine an entirely different set of constellations. In the meantime, for us on Earth, the constellations are a handy way to locate a star in the sky. On Earth, we see different constellations as we travel to different parts of the globe. The fact that some constellations were visible in the northern hemisphere and not the southern hemisphere, and vice-versa, was used more than 2000 years ago by Greek astronomers to argue that the Earth is round.

Long before the invention of the telescope, early civilizations invented star patterns and named them after animals, objects, heroes, gods, and beasts from stories and myths. Many of these myths were probably created to explain changes in the sky due to seasons, etc. The ancient Greeks named many constellations. For example, they told the story of Orion, the hunter, who leaped into the sea to escape a scorpion's bite, which explained why the constellation Orion disappears from the sky when the constellation Scorpius rises. Different civilizations imagined different patterns, and some stars were included in more than one pattern. Over time, the situation became confusing.

In 1929 the International Astronomical Union defined 88 constellations that are today recognized as the 'official' constellations. Many of these constellations are derived from the complex creations of Greek mythology, like Andromeda, Perseus, and Orion. Others came from ancient cultures such as the Egyptians and Chaldeans and still others were not defined until the 17th and 18th century. In the past, people used the constellations as markers. Some used the constellations to navigate their boats across the sea, to mark seasons of the year, or to locate special stars. Today, astronomers still use constellations as a handy marker to indicate a general area of the sky where far away celestial objects appear. Many of these extremely distant objects can be seen only with powerful telescopes.


An uneven distribution of mass inside the Earth. The Earth
Amazing GRACE

Gravity has an effect on everyone and everything on Earth. Although we can't see it, smell it, taste it or touch it, we know it's there. Although scientists already know quite a bit about this invisib ...
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Among the biggest challenges for GP-B is keeping its Science Instrument Assembly constantly cooled to a temperature of 1.8 Kelvin, or minus 271.4 degrees Celsius (slightly above absolute zero), which will last 18 to 24 months.
GP-B: More Than Just a Pretty Face

Questions about the ways space, time, light and gravity relate to each other have been asked for eons. Theories have been offered, yet many puzzles remain to be solved. No spacecraft ever built has re ...
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Venus Is Hot Stuff

At first glance, if Earth had a twin, it would be Venus. The two planets are similar in size, mass, composition, and distance from the Sun. But there the similarities end. Venus has no ocean. Venus is ...
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Science Quote

'The strength and weakness of physicists is that we believe in what we can measure. And if we can't measure it, then we say it probably doesn't exist. And that closes us off to an enormous amount of phenomena that we may not be able to measure because they only happened once. For example, the Big Bang. ... That's one reason why they scoffed at higher dimensions for so many years. Now we realize that there's no alternative... '

Michio Kaku
(1947-)


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