satellites tagged posts

NASA Satellites reveal Abrupt Drop in Global Freshwater Levels

An angular statellite orbits high over the earth in an artists ipression of the GRACE mission. A radar and laser beams link the satellite to a companion satallite far in the distance.
GRACE satellites measure gravity as they orbit the planet to reveal shifting levels of water on the Earth (artist’s concept).
NASA/JPL-Caltech

An international team of scientists using observations from NASA-German satellites found evidence that Earth’s total amount of freshwater dropped abruptly starting in May 2014 and has remained low ever since. Reporting in Surveys in Geophysics, the researchers suggested the shift could indicate Earth’s continents have entered a persistently drier phase.

From 2015 through 2023, satellite measurements showed that the average amount of freshwater stored on land—that includes liquid surface water like lakes and rivers, plus water in aquifers underground—was 290 cubic miles (1,200 cubic km) lower than the average levels from 2002 through 2014, said...

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Lightning strikes kick off a game of electron pinball in space

When lightning strikes, the electrons come pouring down. In a new study, researchers at the University of Colorado Boulder, led by an undergraduate student, have discovered a novel connection between weather on Earth and space weather. The team utilized satellite data to reveal that lightning storms on our planet can dislodge particularly high-energy, or “extra-hot,” electrons from the inner radiation belt—a region of space enveloped by charged particles that surround Earth like an inner tube.

The team’s results could help satellites and even astronauts avoid dangerous radiation in space. This is one kind of downpour you don’t want to get caught in, said lead author and undergraduate Max Feinland.

“These particles are the scary ones or what some people call ‘killer electrons,'...

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The Milky Way’s satellites help reveal link between Dark Matter Halos and Galaxy Formation

A still image from a simulation of the formation of dark matter structures from the early universe until today. Gravity makes dark matter clump into dense halos, indicated by bright patches, where galaxies form. In this simulation, a halo like the one that hosts the Milky Way forms, and a smaller halo resembling the Large Magellanic Cloud falls toward it. SLAC and Stanford researchers, working with collaborators from the Dark Energy Survey, have used simulations like these to better understand the connection between dark matter and galaxy formation. Credit: Ralf Kaehler/SLAC National Accelerator Laboratory

Just as the sun has planets and the planets have moons, our galaxy has satellite galaxies, and some of those might have smaller satellite galaxies of their own...

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