The Planetary Blog

Updates from beyond this world

[earthstory]

Continental Crumple Zone: Zagros

The Arabian tectonic plate and the Eurasian plate meet in continental collision at the Zagros mountain range in southwest Iran. The Zagros are among the world’s most seismically active mountains, formed as a “fold-and-thrust” belt around 1500km long and 300 km wide. Part of the Alpine-Himalayan belt, Earth’s crust is shortening at up to 9 mm per year at the Zagros Mountains, accommodated as both thrust faults in the basement rocks and folds in the overlying sediments.

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[planetaryblog]

'Don't go to the beach': Waves up to 6 stories forecast for Bay Area beaches

Massive mountainous waves, in some cases up to six stories tall, are in the forecast for San Francisco Bay Area beaches.

[nationalsciencefoundation]

Seismic study reveals huge amount of water dragged into Earth’s interior

Slow-motion collisions of tectonic plates under the ocean drag about three times more water down into the deep Earth than previously estimated, according to a first-of-its-kind seismic study that spans the Mariana Trench, a crescent-shaped trench in the Western Pacific that measures 1,500 miles long and is the deepest ocean trench in the world. The observations from the trench have important implications for the global water cycle, according to researchers at Washington University in St. Louis whose work is supported by the National Science Foundation.

Researchers listened to more than a year’s worth of Earth’s rumblings, from ambient noise to actual earthquakes, using a network of 19 ocean-bottom seismographs deployed across the Mariana Trench, along with seven island-based seismographs. The Mariana Trench is where the western Pacific Ocean plate slides beneath the Mariana Plate and sinks deep into the Earth’s mantle as the plates slowly converge. The new seismic observations paint a more detailed picture of the Pacific Plate bending into the trench, resolving its 3D structure and tracking the relative speeds of types of rock that have different capabilities for holding water.

[earthstory]

Alteration

Volcanic rocks are born as lavas or layers of ash, and stack up eruption after eruption, sometimes thick enough to form islands such as Japan and Iceland (in the featured image) on the mid Atlantic ridge. Much of the rock in the latter is basaltic, but gets transformed after its birth into a variety of chewed up and brightly coloured rock remnants.

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[maptitude1]

The National Park Service’s map of Maui and Haleakala National Park

[parallel-awhite]

#place vs. #placename

The geomorphic coherence of these forms - the coherence and their sheer scale - the sheered face of the rock - the water and the history of the water in relation to the rock - its mineral existence - which speaks to the mineral existence of this world. 

The fact that this rock is located in a place to which we refer as Spain - along a coastal plane known as the Basque coast - in a particular area referred to as Gipuzkoa - must be dealt with.  One first has the impression of the place and then one is asked to integrate one’s stored knowledge about that place - to absorb all that accrues to the specificity - the Spanish aspects - the Basque aspects - the history - the imaginings - the human aspects.  

But first we have the direct full frontal sheer gorge and sheer gorgeousness and striated wonder and awesome scale and primordial freshness that is communicated “here” [in this image]. 

[earthstory]

Birds nest inclusion A hexagonal crystal of the pink variety of beryl called morganite (see http://tinyurl.com/mq7j9er) grew alongside or around a curious configuration of feldspar crystals forming a wonderful inner sculpture imprisoned within the rosy gem, The piece was mined in the Kunar province of Afghanistan and measures 8.4 x 6.9 x 4.6 cm. Loz Image credit: Joe Budd/Rob Lavinsky/iRocks.com

[planetaryblog]

Map shows haze in Philly came from California wildfire smoke

As California's devastating wildfires burn through a second week of destruction, the wider atmospheric effects are beginning to show up in f

[earthstory]

What a place to live…..

Part of the Izu chain in the Phillipine sea located within a national park 350km south of Tokyo, Aogashima is the smallest inhabited island in Japan, with a mere 170 dwellers. As you can see, the population is living in the crater of an emergent submarine volcano, with nine square km poking out as land.

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[fuckyeahfluiddynamics]

With some help from Physics Girl and her friends, Grant Sanderson at 3Blue1Brown has a nice video introduction to turbulence, complete with neat homemade laser-sheet illuminations of turbulent flows. Grant explains some of the basics of what turbulence is (and isn’t) and gives viewers a look at the equations that govern flow – as befits a mathematics channel! 

There’s also an introduction to Kolmogorov’s theorem, which, to date, has been one of the most successful theoretical approaches to understanding turbulence. It describes how energy is passed from large eddies in the flow to smaller ones, and it’s been tested extensively in the nearly 80 years since its first appearance. Just how well the theory holds, and what situations it breaks down in, are still topics of active research and debate. (Video and image credit: G. Sanderson/3Blue1Brown; submitted by Maria-Isabel C.)

[wonders-of-the-cosmos]

Hello. Quick yet complicated question... How can the universe be "flat" if gravity curves spacetime?

Well, to be honest, I do not fully understand it, it’s hard to imagine because we live in a 3D universe (three spatial dimensions plus a temporal dimension), so when we say that the universe is flat, it is not in the same sense that a piece of paper is flat, but it means that geometry of the universe is such that the parallel lines never intersect, the angles in a triangle will always add up to 180 degrees, and the cube corners will always make right angles.

If Ω = 1, the universe is flat

If Ω > 1, there is positive curvature

if Ω < 1 there is negative curvature

And also in relation to curvature. When we see a “ simulation ” of the curvature in the space-time fabric, it is always shown in 2D, but this is just a simple way to demonstrate, in a 3D universe the visualization is a bit different and more complicated to understand.

2D ↑

3D ↑

[unhistorical]

William Henry Jackson “Mammoth Hot Springs, Gardiner’s River, Montana,” 1871 “White Mountain Hot Springs,” 1871 “Grand Canyon of the Colorado River,” 1883

[unhistorical]

William Henry Jackson “Mammoth Hot Springs, Gardiner’s River, Montana,” 1871 “White Mountain Hot Springs,” 1871 “Grand Canyon of the Colorado River,” 1883

[just--space]

Gravity’s Rainbow : Saturn’s rings display their subtle colors in this view captured on Aug. 22, 2009, by NASA’s Cassini spacecraft. (via NASA)

[just--space]

NGC 7635: The Bubble Nebula : Blown by the wind from a massive star, this interstellar apparition has a surprisingly familiar shape. Cataloged as NGC 7635, it is also known simply as The Bubble Nebula. Although it looks delicate, the 7 light-year diameter bubble offers evidence of violent processes at work. Above and left of the Bubble’s center is a hot, O-type star, several hundred thousand times more luminous and some 45 times more massive than the Sun. A fierce stellar wind and intense radiation from that star has blasted out the structure of glowing gas against denser material in a surrounding molecular cloud. The intriguing Bubble Nebula and associated cloud complex lie a mere 7,100 light-years away toward the boastful constellation Cassiopeia. This sharp, tantalizing view of the cosmic bubble is a composite of Hubble Space Telescope image data from 2016, reprocessed to present the nebula’s intense narrowband emission in an approximate true color scheme. via NASA

[traverse-our-universe]

Trapezium Cluster: four-star powerhouse (from the book Hubble’s Universe: Greatest Discoveries and Latest Images)

[alxndrasplace]

(NASA/JPL)  Orion’s Dreamy Stars

A colony of hot, young stars is stirring up the cosmic scene in this new picture from NASA’s Spitzer Space Telescope. The image shows the Orion nebula, a happening place where stars are born. The young stars dip and peak in brightness due to a variety of reasons. Shifting cold and hot spots on the stars’ surfaces cause brightness levels to change, in addition to surrounding disks of lumpy planet-forming material, which can obstruct starlight. Spitzer is keeping tabs on the young stars, providing data on their changing ways.

The hottest stars in the region, called the Trapezium cluster, are bright spots at center right. Radiation and winds from those stars has sculpted and blown away surrounding dust. The densest parts of the cloud appear dark at center left.