Artikel: NASA wil mensen naar Venus sturen

Gareth Dorrian & Ian Whittaker / LiveScience

Popular science fiction of the early 20th century depicted Venus as some kind of wonderland of pleasantly warm temperatures, forests, swamps and even dinosaurs. In 1950, the Hayden Planetarium at the American Natural History Museum were soliciting reservations for the first space tourism mission, well before the modern era of Blue Origins, SpaceX and Virgin Galactic. All you had to do was supply your address and tick the box for your preferred destination, which included Venus.

Today, Venus is unlikely to be a dream destination for aspiring space tourists. As revealed by numerous missions in the last few decades, rather than being a paradise, the planet is a hellish world of infernal temperatures, a corrosive toxic atmosphere and crushing pressures at the surface. Despite this, NASA is currently working on a conceptual manned mission to Venus, named the High Altitude Venus Operational Concept —(HAVOC).

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Artikel: Extracting carbon dioxide from the air is possible. But at what cost?

The Economist

IN MAY some 250 scientists and policy types from around the world convened in Gothenburg, Sweden, to discuss a dirty secret of the three-year-old Paris climate agreement. Virtually all simulations which chart paths toward meeting that compact’s goal—to keep temperature rise “well below” 2°C relative to pre-industrial levels—assume not just a sharp reduction in actual emissions but also the removal of carbon dioxide from the atmosphere on a massive scale. One reason such “negative emissions” have been absent from climate discussions—the Swedish shindig being the first of its kind—is that no one has a good idea of how exactly to bring them about. The obvious solution is to plant lots of trees, to convert CO2into wood. But this would mean foresting an area with a size somewhere between that of India and Canada. Alternative, engineered fixes have been dogged by potentially stratospheric costs, uncertain efficacy or both.

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