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seeinnovation:

Motivated by the social impact and scientific challenges posed by the Deep Water Horizon oil spill, a University of Miami oceanographer has modeled the physics of buoyant oil plumes rising from the ocean floor. He determined the circumstances required for a buoyant plume to remain below the surface and spread out in vertical layers. Here, you see a side view of the modeled buoyant plume. Learn more at NSF’s website devoted to science outcomes, SEE Innovation. Credit: Tamay Ozgokmen, University of Miami

unknownskywalker:

Opportunity’s 8th anniversary view from ‘Greeley Haven’

This mosaic of images taken in mid-January 2012 shows the windswept vista northward (left) to northeastward (right) from the location where NASA’s Mars Exploration Rover Opportunity is spending its fifth Martian winter, an outcrop informally named “Greeley Haven.”

The view includes sand ripples and other wind-sculpted features in the foreground and mid-field. The northern edge of the the “Cape York” segment of the rim of Endeavour Crater forms an arc across the upper half of the scene.

Opportunity landed on Mars on Jan. 25, 2004. It has driven 21.4 miles (34.4 kilometers) as of its eighth anniversary on the planet. In late 2011, the rover team drove Opportunity up onto Greeley Haven to take advantage of the outcrop’s sun-facing slope to boost output from the rover’s dusty solar panels during the Martian winter.

The image combines exposures taken through Pancam filters centered on wavelengths of 753 nanometers (near infrared), 535 nanometers (green) and 432 nanometers (violet). The view is presented in false color to make some differences between materials easier to see.

14-billion-years-later:

Electromagnetism

Possibly one of the most important things in anyone’s life, but also one of the least acknowledged or understood. Electromagnetism is one of the 4 fundamental forces (the others being the strong and weak interactions and of course gravity) and it literally shapes the world around us. It’s the force that holds electrons around atoms and also what gives shape to the molecules and structures that we see in the world around us. In fact it’s what allows us to see the world around us as light is essentially just a changing magnetic and changing electric field at right angles. This is because a change in one of the fields creates the other and vice versa, so a growing or shrinking magnetic field will cause a fluctuating electric field, which will in turn create another magnetic field. This is what allows light waves to propagate through empty space; it is its own medium.

A changing magnetic/electric field is also the same principle used in electric motors and makes up the last two of Maxwell’s equations: Faraday’s Law of Induction (that a magnet in motion generates a current in a wire) and Ampere’s Law (that a charged particle in motion generates a magnetic field). The uses of electromagnetism are far more important than those of gravity yet it remains the awkward middle child of the force family. From transformers to our own forms, it is electromagnetism we have to thank.

The image shows how magnetism and electricity can be combined to make a motive force. Neat huh? Pretty easy to make at home too if you’re bored.

unknownskywalker:

Earth from Space: Golden curves

The curving sands in central northern Iran’s salt desert, Dasht-e Kavir, can be seen in this image from the Ikonos-2 satellite acquired on 13 November 2008. Here, clays and sand soils have a high surface salt content owing to the concentration of minerals from high summer evaporation. Iran is one of the world’s most important mineral producers.

Earth-observing satellites are useful for finding and monitoring natural resources like minerals. Satellites can directly identify different minerals and recognise large-scale geological structures related to mineral deposits that ground-based surveys may have difficulty detecting.

Near the area pictured are biosphere reserves, national parks and wildlife refuges. When dealing with large, uninhabited areas like this, remote sensing can provide a simple solution to managing protected land.

(Source: abasa)