Posts Tagged ‘wissenschaft’

Wie viele Planeten gibt es in unserer Galaxie?

Freitag, Juni 18th, 2010

Hochrechnungen der Kepler-Mission sagen: Mindestens 1,4 Milliarden!

They have found, definitely, 306 new extra-solar planets, including 5 systems with multiple planets. Unlike previous searches, most of the planets that Kepler found are Neptune-sized (the smallest gas giant in our Solar System) or smaller!

That’s very, very promising! But they’ve left us with the ultimate teaser: they are withholding data — for a year — on 400 particularly juicy candidates!

What did they find? Are they Earth-sized planets? Are they planets in the habitable zones around their stars? Are they “just barely” detections, and they want to get some more data?

If we assume that each one is a planet, that brings us to 706 planets around 100,000 stars. Since our galaxy has around 200 billion stars, we can figure out that there ought to be — wait for it — at least 1.4 billion planets in our galaxy!

And that, mind you, is a lower limit, as this only will see planets orbiting edge-on to their stars! But it’s the biggest lower limit we’ve ever been able to set, and you’re among the first to know!

Katalog der bisher bekannten Exoplaneten.

BBC Dokumentation: Die Wunder des Sonnensystems

Dienstag, März 9th, 2010

“Professor Brian Cox visits some of the most stunning locations on earth to describe how the laws of nature have carved natural wonders across the solar system. In this first episode, Brian explores the powerhouse of them all, the sun. In India, he witnesses a total solar eclipse, and in Norway he watches the battle between the sun’s wind and earth, as the night sky glows with the northern lights.”

Youtube Playlist; via Nerdcore, misterhonk

Baltimore Gun Club

Sonntag, Januar 24th, 2010


John Hunter möchte mit einer 1,1 KM langen, 500 M tief unter die Meeresoberfläche getauchten Kanone Nachschub und “robuste” Satelliten in den Orbit befördern. Ernsthaft. Robust müssen sie auch sein, um die Beschleunigung von Null auf 20.000 km/h mit 3200 G zu überstehen. Wahrscheinlich wird selbst der Astronautenfraß danach etwas matschiger als gewöhnlich schmecken.

Building colossal guns has been Hunter’s pet project since 1992, when, while a physicist at Lawrence Livermore National Laboratory, he first fired a 425-foot gun he built to test-launch hypersonic engines. Its methane-driven piston compressed hydrogen gas, which then expanded up the barrel to shoot a projectile. Mechanical firing can fail, however, so when Hunter’s company, Quicklaunch, released its plans last fall, it swapped the piston for a combustor that burns natural gas. Heat the hydrogen in a confined space and it should build up enough pressure to send a half-ton payload into the sky at 13,000 mph.

via antifuchs