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Signals traveling from the gut to the brain may help turn meals into lasting memories。 Rats showed stronger memory activity after consuming nutritious foods, but not after drinking sweet liquids with little or no nutritional value。 Blocking the vagus nerve erased this effect and made it harder for the animals to remember where food had been located
Scientists have built the first all-optical photonic time crystal, allowing them to reshape the behavior of terahertz light at extraordinary speeds。 The breakthrough could open the door to ultrafast computing, smarter communication systems, advanced imaging, and a new generation of highly tunable lasers
Physicists have uncovered a surprising limit to electrical resistance caused by particles colliding。 Using ultracold potassium atoms trapped in a grid of light, researchers created a highly controlled stand-in for electrons moving through a solid。 As collisions became more frequent and intense, resistance initially rose, but eventually hit a ceilin
Cosmic expansion allows distant galaxies to move away faster than light, while still letting us see ancient light they emitted when they were much closer。 Eventually, accelerating expansion will push nearly every galaxy beyond our Local Group out of sight, making the Universe appear almost empty
NASA’s Swift Observatory observed a supermassive black hole ripping apart a star more than 30,000 light-years from the center of a distant galaxy。 The extraordinary flare briefly outshone its entire host galaxy in ultraviolet light and revealed a black hole about a million times the Sun’s mass
Wavelength and intensity in the infrared are translated into colors in the visible
Astronomers may have been listening for alien civilizations in only a small slice of the radio spectrum while overlooking a largely unexplored range of higher frequencies。 Using archived data from the ALMA telescope in Chile, researchers conducted the observatory’s first SETI survey, searching for narrow signals that could indicate advanced technol
NASA’s Psyche spacecraft aced its Mars flyby, using the planet’s gravity to speed toward its 2029 encounter with a metal-rich asteroid。 The spacecraft tested its cameras, magnetometer, and particle-detecting instruments, capturing unusual views of Mars and measuring its magnetic environment。 It also detected neutrons from the planet and spotted the
Sony doesn't think the move will hurt it financially
A new analysis suggests the Sun holds far more silver than earlier estimates indicated。 More advanced models of the solar atmosphere raised the calculated amount by 55 percent, bringing it into much closer agreement with ancient meteorites。 The technique may also help scientists track the cosmic origins of silver and other heavy elements
Scientists have created an “electron lighthouse” that uses laser light to launch and steer electrons through a semiconductor without an applied electrical field。 The quantum effect could eventually improve optical sensors, communications, imaging, and information storage
Europa’s hidden ocean has made the icy moon one of the solar system’s most promising places to search for habitable conditions。 Scientists have hoped that water from this deep ocean might rise through cracks and form shallow reservoirs that future spacecraft could more easily study。 New simulations suggest that journey is unlikely because turbulent