Category Archives: Physics

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.

From the Earth to Space

Astronomy Picture of the Day: Rocket Launch as Seen from the Space Station. (YouTube, 1:37min) “Video Credit: ISAA, NASA, Expedition 57 Crew (ISS); processing: Riccardo Rossi (ISAA, AstronautiCAST); music: Inspiring Adventure Cinematic Background by Maryna.”

“Have you ever seen a rocket launch — from space? A close inspection of the featured time-lapse video will reveal a rocket rising to Earth orbit as seen from the International Space Station (ISS). The Russian Soyuz-FG rocket was launched ten days ago from the Baikonur Cosmodrome in Kazakhstan, carrying a Progress MS-10 (also 71P) module to bring needed supplies to the ISS. Highlights in the 90-second video (condensing about 15-minutes) include city lights and clouds visible on the Earth on the lower left, blue and gold bands of atmospheric airglow running diagonally across the center, and distant stars on the upper right that set behind the Earth. A lower stage can be seen falling back to Earth as the robotic supply ship fires its thrusters and begins to close on the ISS, a space laboratory that is celebrating its 20th anniversary this month.”

“We’re changing a mass realization system that we’ve had for 129 years”

NPR Science: Say Au Revoir To That Hunk Of Metal In France That Has Defined The Kilogram.

“The world is about to say au revoir to Le Grand K, a cylinder of platinum and iridium that has long reigned over the world’s system of weight measurement.

Le Grand K was forged in 1879 and is held in a locked vault outside Paris — revered and kept under lock and key because its mass, a little over 2 pounds, is the official definition of the kilogram.

But this is will soon change. On Friday, the international General Conference on Weights and Measures will meet in Versailles, France, to vote on whether to redefine the kilogram.

The vote is expected to be unanimous, a mere formality after years of work. Going forward, the world’s system of mass measurement will not be based on some special hunk of metal, but rather on unalterable features of the universe — such as the speed of light, time and Planck’s constant, a number that helps scientists figure out the energy of a photon of light, given its wavelength.”