Topological transport of light is the photonic analog of topological electron flow in certain semiconductors. In the electron case, the current flows around the edge of the material but not through the bulk. It is "topological" in that even if electrons encounter impurities in the material the electrons will continue to flow without losing energy.
Heavens
A train of developing tropical low pressure areas stretch from the Eastern Pacific Ocean into the Central Pacific and they were captured in an image from NOAA's GOES-West satellite on August 1. The train of five tropical lows include the remnants of Tropical Storm Genevieve and newly developed Tropical Storm Iselle.
At 11 a.m. EDT (1500 UTC) the National Hurricane Center noted that the center of Tropical Storm Bertha was located near latitude 14.0 north and longitude 58.9 west, about 70 miles (110 km) southeast of Barbados. It was moving toward the west-northwest near 21 mph (33 kph) and that general motion is expected to continue for the next couple of days. NHC noted that Bertha is expected to move through the central Lesser Antilles during the night (August 1) and approach the Virgin Islands and Puerto Rico on Saturday, August 2. The estimated minimum central pressure is 1008 millibars.
NASA satellite data showed Tropical Storm Halong's "best side" or most powerful side was east of its center. That's where the coldest cloud top temperatures and strongest thunderstorms appeared on satellite imagery.
Tropical Storm Iselle was born in the Eastern Pacific Ocean soon after NASA's Aqua satellite gathered infrared imagery on the storm that showed powerful thunderstorms wrapping into developing storm's center. Iselle is not close enough to land to cause any watches or warnings.
CAMBRIDGE, Mass-- Researchers at MIT and in Saudi Arabia have developed a new way of making surfaces that can actively control how fluids or particles move across them. The work might enable new kinds of biomedical or microfluidic devices, or solar panels that could automatically clean themselves of dust and grit.
Having a companion in old age is good for people — and, it turns out, might extend the chance for life on certain Earth-sized planets in the cosmos as well.
Planets cool as they age. Over time their molten cores solidify and inner heat-generating activity dwindles, becoming less able to keep the world habitable by regulating carbon dioxide to prevent runaway heating or cooling.
In this month's issue of Physics World, Ashley Dale from the University of Bristol warns of the "catastrophic" and "long-lasting" impacts of "solar super-storms" and the dangers we face if the threat continues to go unnoticed.
San Antonio — July 31, 2014 — A new terrestrial bombardment model developed by an international group of scientists led by Southwest Research Institute (SwRI) indicates that Earth's surface was heavily reprocessed — or melted, mixed and buried — as a result of giant asteroid impacts more than four billion years ago.
Observations by NASA's Fermi Gamma-ray Space Telescope of several stellar eruptions, called novae, firmly establish these relatively common outbursts almost always produce gamma rays, the most energetic form of light.
"There's a saying that one is a fluke, two is a coincidence, and three is a class, and we're now at four novae and counting with Fermi," said Teddy Cheung, an astrophysicist at the Naval Research Laboratory in Washington, and the lead author of a paper reporting the findings in the Aug. 1 edition of the journal Science.
Astronomers using NASA's Hubble Space Telescope have unexpectedly discovered the most distant galaxy that acts as a cosmic magnifying glass. Seen here as it looked 9.6 billion years ago, this monster elliptical galaxy breaks the previous record-holder by 200 million years.
These "lensing" galaxies are so massive that their gravity bends, magnifies, and distorts light from objects behind it, a phenomenon called gravitational lensing. Finding one in such a small area of the sky is so rare that you would normally have to survey a region hundreds of times larger to find just one.
TEMPE, Ariz. - The Universe is home to a variety of exotic objects and beautiful phenomena, some of which can generate almost inconceivable amounts of energy. ASU Regents' Professor Sumner Starrfield is part of a team that used the Large Area Telescope (LAT) onboard NASA's Fermi Gamma-ray Space Telescope satellite to discover very high energy gamma rays (the most energetic form of light) being emitted by an exploding star. The surprising discovery dispels the long-held idea that classical nova explosions are not powerful enough to produce such high-energy radiation.
The resurrected Tropical Depression Genevieve appears squeezed between three other developing areas of low pressure. Satellite data from NOAA and NASA continue to show a lot of tropical activity in the Eastern and Central Pacific Oceans on July 31.
NASA's Tropical Rainfall Measuring Mission or TRMM Satellite passed over Guam as heavy rain fell over the island while Tropical Storm Halong's center passed just to the north of the island.
The TRMM satellite flew above tropical storm Halong on July 31, 2014 at 0904 UTC (August 1, 2014 at 7:04 p.m. local time, Guam).
There are two tropical low pressure areas in the Northwestern Pacific Ocean today and they're close enough to each other to be captured in one image generated from data gathered by NASA's Aqua satellite.