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In the end, however, if the critics quoted in the Science article don’t care about global warming, fine – many people don’t. If they think renewables alone can do it, fine – some people do. I’m sure they’re well-intentioned. However, every leading climate scientist from Jim Hansen on down knows that we will not achieve any of our climate goals without a dramatic increase in both nuclear and renewables.

Since fast-reactors, like those that will be tested in the VITR, can get ten times the power out of the same fuel, can burn spent fuel and even depleted uranium like our old Iraqi tank armor, when we get to fast reactors as a significant portion of our energy we will have several thousand years of low-carbon power on hand.

That’s more energy than exists in all the coal, oil and natural gas in the ground right now.

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A new way of administering drugs for wet age-related macular degeneration might be close.


Two studies by researchers at the University of Birmingham have shown that delivering drugs against the wet form of age-related macular degeneration (AMD) in the form of eyedrops might soon be possible in humans [1, 2].

What is age-related macular degeneration?

AMD is a pathology of the retina, which is a light-sensitive tissue located in the back of the eye and is similar to the film in a non-digital camera. Two-dimensional images are created on the retina and are subsequently transferred to the brain in the form of electrical neural impulses. Near the center of the retina is the macula, an oval-shaped region responsible for central, high-resolution, color vision. In AMD, the macula is damaged, impairing or preventing this kind of vision. AMD is progressive, but it cannot lead to total blindness, as it doesn’t affect peripheral vision. It comes in two forms, wet and dry, with the latter being overwhelmingly more common and, unfortunately, presently incurable. As the name suggests, the highest risk factor for AMD is age; the disease is usually observed only in patients over 50.

Ten months after Hurricane Maria, Adjuntas still loses power any time a heavy rain or wind pounds the rickety power lines feeding this town high in the central mountains of Puerto Rico.

That leaves its 20,000 people once again in the dark, without light, fresh water or air conditioning—except for a handful of homes and businesses glowing in the night thanks to .

The people of Adjuntas call those places “cucubanos,” an indigenous Puerto Rican firefly. They’re part of a small but growing movement to provide the U.S. territory with sustainable, renewable energy independent of the decrepit grid.

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Observations made with ESO’s Very Large Telescope have for the first time revealed the effects predicted by Einstein’s general relativity on the motion of a star passing through the extreme gravitational field near the supermassive black hole in the centre of the Milky Way. This long-sought result represents the climax of a 26-year-long observation campaign using ESO’s telescopes in Chile.

Obscured by thick clouds of absorbing dust, the closest supermassive black hole to the Earth lies 26 000 light-years away at the centre of the Milky Way. This gravitational monster, which has a mass four million times that of the Sun, is surrounded by a small group of stars orbiting around it at high speed. This extreme environment — the strongest gravitational field in our galaxy — makes it the perfect place to explore gravitational physics, and particularly to test Einstein’s general theory of relativity.

New infrared observations from the exquisitely sensitive GRAVITY [1], SINFONI and NACO instruments on ESO’s Very Large Telescope (VLT) have now allowed astronomers to follow one of these stars, called S2, as it passed very close to the black hole during May 2018. At the closest point this star was at a distance of less than 20 billion kilometres from the black hole and moving at a speed in excess of 25 million kilometres per hour — almost three percent of the speed of light [2].

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A water body exists below the Martian south polar ice cap.

Without water, no form of life as we know it could exist. There is therefore great interest in detecting liquid water on other planets of our Solar System. Landforms such as dry river valleys and lakes show that liquid water must have been present on Mars in the past (1). Nowadays, small amounts of gaseous water exist in the Martian atmosphere, and some water ice is found on the planet’s surface. Water droplets were seen condensing onto the Phoenix lander (2), and there may be reoccurring water activity on slopes during the Martian summer (3). However, stable bodies of liquid water have not been found on Mars. Published in Science’s First Release this week, Orosei et al. (4) report an analysis of radar data from the Mars Express mission that shows the existence of stable liquid water below 1.5 km of ice, close to the Martian south pole.

Ice caps similar to those on Earth exist at the Martian north and south poles, known as the North and South Polar Layered Deposits (NPLD and SPLD, respectively). More than 30 years ago, Clifford hypothesized that liquid water might be present below the Martian polar ice caps (5). Despite mean annual air temperatures of around −60°C, lakes exist below Earth’s Antarctic ice sheet (6). Glacier ice insulates the bed from the cold surface. Thus, temperatures at the base of the Antarctic ice sheet, which may be as thick as 4.8 km, can reach the pressure melting point of water; the melting point is reduced owing to the pressure of the ice layer above. Water at the ice base reduces basal friction, leading to increased flow speeds. Finding liquid water below the Martian ice caps might solve ongoing debates about whether the NPLD ice flow is due to ice deformation, deformation of the bed, or gliding over the bed or whether it is not flowing at all (7).

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