Posted on Sep 18, 2018 in Astronomy, Physics, Science, Space, Technology
Since 2009 the European Space Agency’s Gravity field and steady-state Ocean Circulation Explorer (GOCE) has been mapping the Earth’s gravitational field. More potato-shaped than spherical, the latest images shows just how different gravity can be at different points on our planet.
The geoid is a model of the earth that doesn’t follow the surface of the crust but rather the average ocean surface if the oceans were at equilibrium and extended through the continents–in other words, the shape the earth would take based on its existing gravitational field if it wasn’t distorted by tides, currents, and crust features.
In the above image, yellow indicates the strongest gravitational pull while blue indicates the lowest. And while we experience these differences in gravity as negligible, they have a big impact on ocean dynamics and the movement of heat around the planet–key to understanding atmospheric conditions and climate change. (ESA/HPF/DLR)
A new US–German gravity-mapping mission that launched in May reports Nature, has not gathered science data since mid-July because of a problem with a key instrument. The twin satellites of the Gravity Recovery and Climate Experiment Follow-On (GRACE-FO) mission measure minute differences in the distance between them to chart changes in Earth’s gravity. Doing so can reveal the distribution and flow of water and ice across the planet.
But part of a microwave instrument aboard one of the satellites shut itself down on 19 July following signs of an electrical problem. Mission managers are investigating the cause and plan to switch to a back-up system later this month, NASA’s Jet Propulsion Laboratory in Pasadena, California, announced on 14 September.
The Gravity Recovery and Climate Experiment Follow-On mission uses twin probes to monitor Earth’s gravity field.
The Daily Galaxy via Nature and The ESA
Top 10 Space & Science Headlines of 2018
“Spying on Earth’s Most Awesome Creatures” –Scientists Pursue Undiscovered Species of Whales Swimming Below Since the Eocene
The Alien Observatory: Ancient Stars 6-9 Billion Years Old in Milky Way’s Halo –“May Harbor Advanced Civilizations”
“Point of No Return” –MIT Scientist Predicts the Event Horizon for Earth’s 6th Mass Extinction
Artificial Intelligence Is Already Out There, and It’s Billions of Years Old” (WATCH Video)
‘Ghost Signals’ of Extraterrestrial Civilizations Haunt the Milky Way –Suggests the New Drake Equation (WATCH Video)
“Odds That There has Never Been Another Civilization in the Universe One in Ten Billion Trillion” –A Joe Rogan Interview
The Alien Observatory –“The Mystery of Where Extraterrestrial Life is Hiding Deepens”
“We’re Entering Uncharted Territory” –The Exoplanet Revolution May Reveal that Rise of Civilizations May Not be Unusual
“The Big Rip” –When Matter and Spacetime are Gradually Torn Apart Through Expansion of the Universe
“Humans are the First to Arrive at the Interstellar Stage” –Physicist Answers the Fermi Paradox