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If Jurassic Park had instead chosen different geologic eras

A Satellite’s First Look at Earth Has a Stunning Photo of the Sahara

By Katharine Trendacosta

Sentinel-2A conducted its first ever scan of Earth on June 27th. The result was this gorgeous image of the Sahara in central Algeria, showing a glorious terrain of rocks and sand.

Sentinel-2 is the second of six planned Sentinel missions. A pair of satellites with multispectral high-resolution imaging systems, Sentinel 2 will be used to track land use, vegetation stress, soil and water cover, or satellite imagery for emergency response. This Sahara photo is only one of the first photos picked up by the satellite, the rest being shots of Europe.

When did the continents appear?

This gorgeous shot is Alaska’s Augustine volcano, one of the many volcanoes produced by subduction of the Pacific Plate beneath the rocks of Alaska. This lovely cone is just one tiny sliver of the story to tell today – it’s a piece of a continent.

Earth is unique for a number of reasons, including obviously the existence of life and Facebook pages devoted to Earth science. Another unique property of Earth is the existence of volcanoes like this; almost all of the volcanism in the solar system differs from this peak.

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New Horizons color images reveal two distinct faces of Pluto

New color images from NASA’s New Horizons spacecraft show two very different faces of the mysterious dwarf planet, one with a series of intriguing spots along the equator that are evenly spaced. Each of the spots is about 300 miles (480 kilometers) in diameter, with a surface area that’s roughly the size of the state of Missouri.

Scientists have yet to see anything quite like the dark spots; their presence has piqued the interest of the New Horizons science team, due to the remarkable consistency in their spacing and size. While the origin of the spots is a mystery for now, the answer may be revealed as the spacecraft continues its approach to the mysterious dwarf planet. “It’s a real puzzle—we don’t know what the spots are, and we can’t wait to find out,” said New Horizons principal investigator Alan Stern of the Southwest Research Institute, Boulder. “Also puzzling is the longstanding and dramatic difference in the colors and appearance of Pluto compared to its darker and grayer moon Charon.”

New Horizons team members combined black-and-white images of Pluto and Charon from the spacecraft’s Long-Range Reconnaissance Imager (LORRI) with lower-resolution color data from the Ralph instrument to produce these views. We see the planet and its largest moon in approximately true color, that is, the way they would appear if you were riding on the New Horizons spacecraft. About half of Pluto is imaged, which means features shown near the bottom of the dwarf planet are at approximately at the equatorial line.

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Light and dark slate

Slate is a type of metamorphic rock that breaks or cleaves along planes. You’ve probably seen slate used as a building material before – it often forms thin sheets only a couple millimeters across that can be useful as roof tiles or for lining similar flat objects. This is a piece of slate viewed on the flat side – it broke along the weak face and you can see some other possible layers where the rock could break exposed at the fractures on top and bottom.

See the light and dark pattern? That’s the really neat thing about this sample.

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Over 5,000 landslides recorded after the 2015 Nepal Earthquake. Click through for larger image. The team I sent to Nepal blogs here about their mission to assess damage to glacial lakes in central Himalayas. 

The purpose of this inventory and map is to describe the overall spatial distribution of landsliding triggered by the Gorkha earthquake sequence in April-May 2015, not for site-specific assessment. The image quality is low in steep terrain, meaning that precise landslide locations may be inaccurate by up to 100 m. The landslides have been identified and mapped using optical satellite imagery across the area that experienced shaking during the entire earthquake sequence, up to and including 19 June 2015, in addition to some reports from the ground where available. All landslides have been mapped as lines that start at the landslide head or upslope margin, and trace the landslide path to its toe. The colour on the map shows the number of mapped landslides per km2, ranging from 1 to a maximum of 29, to illustrate regional landslide intensity.  Key rivers, valleys and roads are labelled, and the yellow stars indicate the epicentres of the Gorkha (Mw 7.8) and Dolakha (Mw 7.3) earthquakes.

Groundwater depletion worldwide

Groundwater is an important resource worldwide. Unlike surface water, groundwater supplies are typically clear of pollutants like biological waste and groundwater can represent a stable water supply during drought years.

Groundwater supplies are therefore used worldwide as resources for people and for agriculture. In the United States, removal of groundwater from the aquifers in the Central Plains and California is already a major issue as pumping is gradually depleting these aquifers, removing a resource that will take hundreds of years to replenish. This result is well established in the United States – we can even monitor how much the land surface shifts in response (http://tmblr.co/Zyv2Js1W8T6Bu), but what about the rest of the world?

Where there is clean groundwater, it will likely be used as a resource and not every country has the resources available to monitor how rapidly their aquifers are being depleted. Thankfully, there is a way to monitor groundwater resources worldwide: gravity.

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Tugtupite

found only in the Arctic

Its Inuit name, Tuttupit, means “Reindeer Blood”

“Tugtupite was first discovered as a gemstone in 1957 at Tugtup Agtakôrfia, Greenland. To date it has only been found in two other locations - Mt. St. Hilaire in Canada and the Kola Peninsula in Russia, but only tugtupite from Greenland is richly colored and valued as a gemstone.

Many of the stones respond to warmth. When held firmly in a warm hand or exposed to sunlight, the rather pale red stone suddenly turns into a beautiful dark red gem.

An Inuit legend says that lovers can cause the stone to glow fiery red just from the heat of their romance, announcing the intensity of their love.”