Tag

Earth Rotation

All articles tagged with #earth rotation

science7 days ago•3 min saved

Earth’s days drift longer as the planet slows under lunar pull

Earth’s day is gradually lengthening—about 1.7 milliseconds per century—primarily due to tidal braking by the Moon, which is gradually moving away from Earth (~3.8 cm/year). Additional tiny effects come from shifts in Earth’s interior, winds, and ocean currents, including climate-driven glacier melt that redistributes mass. Scientists track these minute changes with atomic clocks and techniques like VLBI. A full stop would take tens of billions of years, well beyond the Sun’s red-giant era.

via BBC Sky at Night Magazine|

#atomic-clocks #climate-change #earth-rotation

science13 days ago•12 min saved

Ancient clam reveals a 372-day year and a faster Earth

Researchers analyzed daily growth rings in the Cretaceous clam Torreites sanchezi from Oman to estimate that ~70 million years ago a year contained about 372 days, with each day ~23.5 hours long. This implies Earth spun faster then, slowed by tidal interactions with the Moon (which was closer and is receding today at ~3.8 cm/year). The study’s high-resolution method—combining daily laminae counts and chemistry—could be applied to other well-preserved shells to refine the history of Earth's rotation.

via Space Daily|

#days-per-year #earth-rotation #fossil-clam

space13 days ago•12 min saved

Earth’s Tidal Brake Pushes Moon Away, Extending Our Day

Tidal friction is slowly transferring Earth's rotational energy to the Moon, lengthening our days by about two milliseconds per century and pushing the Moon outward by roughly 3.8 centimeters per year, a drift measured for decades with lasers reflecting off Apollo-era lunar mirrors. The mechanism, rooted in gravity and corroborated by geological and historical records, will continue to alter the Earth–Moon dynamic, with long-term implications for day length, eclipses, and climate-linked sea-level changes in coming centuries.

via Space Daily|

#apollo-retroreflectors #earth-rotation #lunar-laser-ranging

science1 month ago•11 min saved

Earth’s inner core slows and drifts backward in a 70-year seismic rhythm

Seismic data indicate Earth's solid inner core, long spinning slightly faster than the surface, slowed to match the surface around 2009–2010 and has since fallen behind, effectively drifting backward relative to the rest of the planet. The motion is a relative one (to the mantle) and likely part of a ~70-year oscillation that also influences length of day and the magnetic field; the evidence is indirect and debated, with ongoing work to confirm the oscillation model over the coming decade.

via Space Daily|

#earth-rotation #geophysics #inner-core

science2 months ago•13 min saved

Ancient corals reveal Earth's day was about 22 hours 380 million years ago

Earth’s rotation has been slowing for billions of years due to tidal friction with the Moon, lengthening a day from roughly 22 hours in the Devonian (about 385–410 million years ago) to today’s 24 hours. Fossil corals show ~400 daily growth lines per year in the Middle Devonian, giving a day of ~21.9 hours, while Pennsylvanian corals imply ~22.4-hour days; the Moon’s recession (~3.8 cm/year) and internal mass redistribution also affect daily length in the short term. Proterozoic proxies suggest days as short as ~19 hours, highlighting how Earth’s spin has gradually slowed over deep time.

via Space Daily|

#coral-growth-rings #day-length #devonian

science3 months ago•4 min saved

Human-driven melting slows Earth’s spin at an unprecedented pace

A new study shows Earth's day length is increasing at about 1.33 milliseconds per century—unprecedented in 3.6 million years—driven by mass shifting from melting polar ice into the oceans. The redistribution (around 1000 gigatonnes) slows rotation to a level whose energy is comparable to a magnitude 9.0 earthquake; if high-emission trends continue, climate change could become the leading driver of day-length change by century’s end, with subtle effects on GPS and spacecraft navigation. Researchers note today’s human activity is matching a rare natural event from ~2 million years ago and plan to study other mass-shift processes like groundwater depletion.

via BBC Science Focus Magazine|

#climate-change #earth-rotation #gps-navigation

science4 months ago•6 min saved

Three Gorges Dam Tiny Spin: NASA Calculations Show Subtle Shift in Earth's Rotation

NASA scientists calculated that filling the Three Gorges Dam reservoir would lengthen the length of day by about 0.06 microseconds and shift Earth’s pole by roughly 2 centimeters due to moving 40 cubic kilometers of water higher up; the effect is minuscule compared with the Moon’s tidal slowing and other mass redistributions such as groundwater pumping and ice melt. It’s a real but negligible physical consequence of large-scale engineering, not a weapon or warning.

via The Daily Galaxy|

#earth-rotation #geophysics #mass-redistribution

science5 months ago•5 min saved

Humans Are Lengthening Earth's Day, New Study Finds

Researchers show Earth's day is lengthening by about 1.33 milliseconds per century due to climate-driven mass shifts from melting ice, using fossil foraminifera and a physics-informed deep learning model; the trend could soon surpass the Moon's influence, with implications for communications and space navigation, per a Journal of Geophysical Research: Solid Earth study.

via ScienceAlert|

#climate-change #earth-rotation #foraminifera

science5 months ago•7 min saved

Climate-Driven Spin: Melting Ice Lengthens Earth’s Day and Nudges GPS

New research ties climate-driven water redistribution from melting ice to a measurable slowdown in Earth’s rotation, lengthening the day by about 1.3 milliseconds per century. By analyzing 3.6 million years of benthic foraminifera fossils and deep learning, scientists find this rate is unprecedented in the Quaternary and could, by the end of the century, surpass the Moon’s tidal effect, complicating leap seconds and precise GPS-based navigation.

via The Daily Galaxy|

#climate-change #day-length #earth-rotation

science5 months ago•50 min saved

Climate change lengthens Earth's day, study finds

A study by researchers from the University of Vienna and ETH Zurich finds Earth’s day is lengthening by about 1.33 milliseconds per century due to climate‑driven mass redistribution from melting polar ice and mountain glaciers, moving water from land to oceans and slowing Earth's rotation. This unprecedented pace in 3.6 million years could subtly affect GPS satellites and space missions over time, though the change is far too small for people to notice; by the end of the century, climate-driven effects could rival the Moon's influence on day length.

via Ground News|

#climate-change #earth-rotation #foraminifera

science5 months ago•4 min saved

Moon Slowly Recedes, Extending Earth's Day by Fractions Each Year

NASA measurements show the Moon is moving away from Earth at about 3.8 centimeters per year, transferring rotational energy from Earth to the Moon and gradually lengthening the length of a day. Fossil shells indicate shorter past days (roughly 23.5 hours around 70 million years ago), and the ongoing tidal evolution will continue to lengthen Earth's day by tiny amounts over millions of years.

via The Daily Galaxy|

#earth-rotation #fossil-records #lunar-recession

science8 months ago•5 min saved

Earth's Day Lengths Have Changed Dramatically Over Billions of Years

Research shows that for about a billion years, Earth's day lasted around 19 hours due to a balance between lunar tidal forces and atmospheric tides, with long periods of stability interrupted by episodes of faster or slower rotation, influencing Earth's climate and oxygen levels over geological time.

via Earth.com|

#ancient-earth #day-length #earth-rotation

science8 months ago•4 min saved

Scientists develop device harnessing Earth's rotation for electricity

Scientists in the US have developed a device that can generate tiny amounts of electricity by harnessing Earth's rotation and magnetic field, suggesting a potential, though currently impractical, new energy source if scaled up. The experiment involved a specially shaped ferrite shell that avoids the usual cancellation of voltage caused by electromagnetic forces, producing measurable microvolts as Earth spins. While promising, the technology is in early stages, and further independent testing is needed to verify and explore its scalability.

via Earth.com|

#earth-rotation #electricity-generation #energy-source

science8 months ago•5 min saved

Earth's Day Lengths Have Changed Over Billions of Years

Research shows that for about a billion years, Earth's day lasted roughly 19 hours due to a balance between lunar tidal forces and atmospheric tides, creating long periods where day length remained stable before gradually increasing to 24 hours, impacting Earth's climate and oxygen levels.

via Earth.com|

#ancient-earth #day-length #earth-rotation

science9 months ago•4 min saved

Why Flying Against Earth's Rotation Doesn't Shorten Flight Times

Flying against Earth's rotation does not speed up flights because objects and atmosphere move with the Earth due to inertia and frictional forces, and jet streams—fast-moving air currents influenced by Earth's rotation—affect flight durations more than the Earth's spin itself.

via IFLScience|

#atmosphere #earth-rotation #flight-times