Tag: Earth

Has Earth’s Inner Core Shifted It’s Spin-Cycle…Again?

Leave a comment

Thousands of kilometres beneath your feet, Earth’s interior might be doing something very weird. Many scientists think that the inner core spins faster than the rest of the planet — but sometime in the past decade, according to a study, it apparently stopped doing so…

“We were quite surprised,” say Yi Yang and Xiaodong Song, seismologists at Peking University in Beijing who reported the findings today [January 23rd] in Nature Geoscience.

The results could help to shine light on the many mysteries of the deep Earth, including what part the inner core plays in maintaining the planet’s magnetic field and in affecting the speed of the whole planet’s rotation — and thus the length of a day. But they are just the latest instalment in a long-running effort to explain the inner core’s unusual rotation, and might not be the final word on the matter…

Researchers discovered the inner core in 1936, after studying how seismic waves from earthquakes travel through the planet. Changes in the speed of the waves revealed that the planet’s core, which is about 7,000 kilometres wide, consists of a solid centre, made mostly of iron, inside a shell of liquid iron and other elements. As iron from the outer core crystallizes on the surface of the inner core, it changes the density of the outer liquid, driving churning motions that maintain Earth’s magnetic field…

Now, Yang and Song say that the inner core has halted its spin relative to the mantle. They studied earthquakes mostly from between 1995 and 2021, and found that the inner core’s super-rotation had stopped around 2009. They observed the change at various points around the globe, which the researchers say confirms it is a true planet-wide phenomenon related to core rotation, and not just a local change on the inner core’s surface.

Now, we ALL can feel unsteady on our feet.

Hanging out beyond the moon, this weekend? Watch out!

1 Comment


A couple of these are wandering by, this weekend [credit ESA]

Two skyscraper-size asteroids are zooming toward Earth this weekend, with one making its closest approach on Friday (July 29) and the second whizzing by on Saturday (July 30).

The first asteroid, dubbed 2016 CZ31, will fly by around 7 p.m. ET (23:00 GMT) on Friday, whizzing at an estimated 34,560 mph (55,618 km/h, according to NASA.

Astronomers estimate that the asteroid measures about 400 feet (122 meters) across at its widest point, making it about as wide as a 40-story building is tall. The asteroid will safely miss our planet…According to NASA, this space rock makes close approaches to Earth every few years, with the next one scheduled for January 2028.

On Saturday, a second, ever larger asteroid will skim past our planet, albeit at a greater distance from Earth. That asteroid, named 2013 CU83, measures approximately 600 feet (183 m) across at its widest visible point, and will pass by about 4,320,000 miles (6,960,000 km) from Earth, or about 18 times the average distance between Earth and the moon…

…Space agencies take planetary defense very seriously. In November 2021, NASA launched an asteroid-deflecting spacecraft called the Double Asteroid Redirection Test (DART), which will slam directly into the 525-foot-wide (160 m) asteroid Dimorphos in autumn 2022. The collision won’t destroy the asteroid, but it may change the space rock’s orbital path slightly, Live Science previously reported. The mission will help test the viability of asteroid deflection, should some future asteroid pose an imminent danger to our planet.

Just in case you were worried. Or needed something more than politics to worry about.

Google Earth Timelapse shows you how much humans are changing Earth

1 Comment

Human beings have had a massive impact on this planet, and Google Earth is launching a new time-lapse feature to show everyone exactly what that looks like.

Whether it’s climate change, deforestation, desertification, or any number of other things, the severity of human activity can be impossible to grasp until you see it for yourself. The new Google Earth feature, called Timelapse, will enable you to do just that — and what’s more, it’s already available to try.

Google will be updating Timelapse every year from now on, and it promises to keep it updated for at least another decade. That way, we’ll be able to continue to see how our planet is changing, and what human beings are doing to continually mess the whole place up.

Same as it ever was. Same as it ever was. Same as it ever was…

Greenland ice is melting faster than ever — affecting Earth’s axial rotation

1 Comment


Click to enlarge — Reuters/Bob Strong

❝ Researchers from the Danish Meteorological Institute had to double-check their instruments to make sure they were working properly. It was hard to believe that 12% of the Greenland ice sheet was melting this early in the year; the previous record was set in 2010 when 10% of the ice sheet was melting in May.

❝ The Earth’s two ice sheets in Antarctica and Greenland and the ice that covers the Arctic sea routinely melt and freeze again each year with the seasons. In the latter years of the 20th century, this ice has been receding more than re-freezing in the cooler months.

Climate scientists are already worried about the melting ice’s contribution to sea level rise. New research from NASA…suggests that the melting ice is also redistributing water enough to affect changes in the Earth’s axial rotation…

❝ The poles have been shifting over time; it’s called the axial “wobble,” and it’s been happening since scientists first recorded data in 1899. In 2000, researchers noticed that the North pole was shifting eastward — toward London, as opposed to Canada, which they attributed to the ice loss in Greenland. As the ice melted, the north pole shifted toward the area with less ice.

The new data, however, indicates that the ice sheets aren’t the only factor affecting axial wobble. The balance of water held in different continents is also making a difference, researchers said. Erik Ivins, a geophysicist and co-author of the paper, explained to Scientific American that he thinks that a recent lack of rainfall in central Eurasia is also pulling the north pole to the east.

❝ “If we lose mass from the Greenland ice sheet, we are essentially putting mass elsewhere. And as we redistribute the mass, the spin axis tends to find a new direction,” Surendra Adhikari, a researcher with Caltech and NASA and co-author of the study, told the Washington Post. He estimates that about 40% of the shift is due to Greenland ice sheet loss; 25% due to Anarctica ice sheet loss, and 25% due to where water is located in continents.

Watch this space. Ivins hopes to have sufficient data added within the year to determine whether or not climate change is the prime factor.

10 adventure trips for every photographer

Leave a comment


Click to enlarge — Chad Copeland

❝ If you’re making travel plans for 2016, these ten places are the best adventure trips for photographers to explore and photograph this year.

❝ For photographers seeking inspiration, or adventure-seeking travelers looking to explore, we’ve put together a list of our favorite adventure trips to take this year.

Beyond their beauty, we believe these locations have more to offer than you might initially think. From hidden caves along the Oregon Coast, to snow-capped mountains in Japan, the following locations are not only worth photographing, but also traveling to see a few sites you might not know exist.

One of the delights of making it to being an old fart is memories – and visual reminders/your own photographs – of the places you visited that stick in your mind for their beauty. I’ve been to a few of these places and they are among my favorites.

Thanks to Om Malik for the reminder.