WDR Doku: Wölfe – Schützen oder schießen? (YouTube, 43:50min) “Die Wölfe sind zurückgekehrt und breiten sich in Deutschland aus. Aber sind Wölfe automatisch gefährlich für den Menschen? Tendenziell sollen Menschen für den Wolf uninteressant sein, aber was sagen Experten? Ob in Niedersachsen, Sachsen oder jüngst in Nordrhein-Westfalen, allerorten werden die Raubtiere gesichtet – Der Wolf ist zurück in der deutschen Wildnis.”
“Just a few months after celebrating its 41st birthday, the Voyager 2 probe has left its familiar environs and entered interstellar space — only the second human-made object in history to do so, after Voyager 1 did it in 2012.
The moment they were waiting for arrived early last month, when Voyager 2 left what’s known as the heliosphere — the vast bubble of plasma and particles generated by the sun and stirred in solar winds. This bubble ends at a boundary called the heliopause, where the sun’s magnetic field peters out and solar winds give way to interstellar space.
By one definition, that also means Voyager 2 — now more than 11 billion miles from the sun — has achieved another, much simpler-to-say feat: leaving the solar system.
It’s not the only definition, though. And the JPL itself marks the end of the solar system at the edge of the sun’s gravitational influence, on the outer boundaries of the Oort Cloud. By that measure, the lab explained, both Voyager probes “have not yet left the solar system, and won’t be leaving anytime soon.”
“It will take about 300 years for Voyager 2 to reach the inner edge of the Oort Cloud,” it said, “and possibly 30,000 years to fly beyond it.”
Astronomy Picture of the Day: Tiny Planet Timelapse .
“You can pack a lot of sky watching into 30 seconds on this tiny planet. Of course, the full spherical image timelapse video was recorded on planet Earth, from Grande Pines Observatory outside Pinehurst, North Carolina. It was shot in early September with a single camera and circular fisheye lens, digitally combining one 24-hour period with camera and lens pointed up with one taken with camera and lens pointed down. The resulting image data is processed and projected onto a flat frame centered on the nadir, the point directly below the camera. Watch as clouds pass, shadows creep, and the sky cycles from day to night when stars swirl around the horizon. Keep watching, though. In a second sequence the projected center is the south celestial pole, planet Earth’s axis of rotation below the tiny planet horizon. Holding the stars fixed, the horizon itself rotates as the tiny planet swings around the frame, hiding half the sky through day and night.”
I love me some sun dogs and halos.
The Washington Post: The story behind an incredible sky scene in New Hampshire. “This was the surreal scene Saturday morning at Franconia Notch in New Hampshire. Steve LeBaron of the New Hampshire Department of Transportation’s Highway Design Bureau captured a stunner of a sky atop Cannon Mountain while skiing.”
Link via MetaFilter.
Alexander Gerst’s ESA Blog: This week in space – 26 November . “As we enter the final month of ESA astronaut Alexander Gerst’s Horizons mission, it is time to reflect once more on the crew’s busy schedule. From science to spacecraft and even spacewalk preparation, there is never a dull moment in space.”