Category Archives: Physics

“North is on the move”

NPR Science: As Magnetic North Pole Zooms Toward Siberia, Scientists Update World Magnetic Model.

“North is on the move, and that’s a problem for your smartphone’s maps.

Earth’s geographic north pole is fixed. But the planet’s magnetic north pole — the north that your compass points toward — wanders in the direction of Siberia at a rate of more than 34 miles per year.

That movement may seem slow, but it has forced scientists to update their model of Earth’s magnetic field a year earlier than expected so that navigational services, including map-based phone apps, continue to work accurately.”

NPR: The North Magnetic Pole Is Shifting East, Fast. “NPR’s Ari Shapiro speaks with Nature reporter Alex Witze about a rapid shift in the Earth’s magnetic poles.”

“If the answer here doesn’t blow your mind, I don’t know what will.”

3Blue1Brown: The most unexpected answer to a counting puzzle and So why do colliding blocks compute pi? and How colliding blocks act like a beam of light…to compute pi. (YouTube, 5:12min and 15:15min and 14:40min)

The connection between the initial experiment and the calculation of π is surprising, and finding two different solutions in physics is even more astounding. The videos are extremely well done, and the presentation helps a lot with understanding the mathematical manipulations.

Mind. Blown.

Link via Futility Closet.

Noch eine Nummer größer, bitte

Deutsche Welle: CERN: Beschleunigerring der Superlative geplant. “Der neue Teilchenbeschleuniger am CERN soll Future Circular Collider heißen und 100 Kilometer lang werden. Die Physiker wollen noch energiereichere Kollisionen als mit dem derzeitigen Large Hadron Collider erreichen.”

“Mit einer Länge von 100 Kilometern wäre der Future Circular Collider (FCC) mehr als dreimal so lang wie der 27 Kilometer lange LHC. In den Kreis des neuen Beschleunigerrings würde praktisch das gesamte Stadtgebiet Genfs passen und obendrauf noch ein Teil Frankreichs.

Das Konzept für den FCC haben die CERN-Physiker am 15. Januar veröffentlicht. Er wird in die “Europäische Strategie für Teilchenphysik” einfließen. Darin soll festgelegt werden, wohin die Reise geht, wenn der LHC voraussichtlich 2035 stillgelegt wird.
Als zweite Option für einen LHC-Nachfolger ist ein kompakter linearer Teilchenbeschleuniger (CLIC) im Gespräch. Doch was am Ende gebaut wird, müssen letztendlich die 22 Mitgliedsstaaten des CERN entscheiden.”

On the Outskirts of our Solar System

NPR Science: Voyager 2 Bids Adieu To The Heliosphere, Entering Interstellar Space.

“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.”

Atmospheric optics

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.