Zeta Ophiuchus

Windswept by Charles Sowers

Though we cannot physically hold wind or see its swirling forms around us, we can definitely feel it.

In order to help visualize wind-currents, artist Charles Sowers created a kinetic installation consisting of 612 aluminum weather vanes called “Windswept” (2011). These were then meticulously placed on the side of the Randall Museum in San Francisco. Through this installation, we are able to see the patterns in the wind; where the currents go, how they turn, and sometimes how wind can abruptly change direction. This gives us a visual representation of the natural, invisible, force which moves around us, and sometimes with enough force, pushes and pulls us.

As the artist states: “Our ordinary experience of wind is as a solitary sample point of a very large invisible phenomenon. Windswept is a kind of large sensor array that samples the wind at its point of interaction with the Randall Museum building and reveals the complexity and structure of that interaction.”

This sort of installation creates a better understanding, and appreciation, of the wind. It is not just one large gust; a single wave can be made up of smaller currents, going in their own directions from the main flow. A dialogue begins to form between the building and the wind, the weather vanes acting as translators.

-Anna Paluch

In engineering we talk a lot about tools. Some people have a favorite collection of software, some a metaphorical belt filled with tips, tricks, and techniques, and others a literal box or lab bench filled with instruments. In my experience, a good engineer not only maintains all three, but seeks...

N44C nebula

On the middle left of the image is a source of its artistic likeness, a network of nebulous filaments surrounding the Wolf-Rayet star. This type of rare star is characterized by an exceptionally vigorous “wind” of charged particles. The shock of the wind colliding with the surrounding gas causes the gas to glow.

The Wolf-Rayet star is part of N44C, a nebula of glowing hydrogen gas surrounding young stars in the Large Magellanic Cloud. Visible from the Southern Hemisphere, the Large Magellanic Cloud is a small companion galaxy to the Milky Way.

What makes N44C peculiar is the temperature of the star that illuminates it. The most massive stars — those that are 10 to 50 times more massive than the Sun — have maximum temperatures of 30,000 to 50,000 degrees Celsius (54,000 to 90,000 degrees Fahrenheit). The temperature of this star is about 75,000 degrees Celsius (135,000 degrees Fahrenheit). This unusually high temperature may be due to a neutron star or black hole that occasionally produces X-rays but is now inactive.

N44C is part of a larger complex that includes young, hot, massive stars, nebulae, and a “superbubble” blown out by multiple supernova explosions. Part of the superbubble is seen in red at the very bottom left of the Hubble image.

Credit: NASA/JPL/Hubble

Transit of Venus

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Métaphore d’un voyage initiatique au coeur de l’oreille adapté aux enfants :

- traversée de l’onde aérienne en avion à l’intérieur du conduit auditif jusqu’à la membrane du tympan

- découverte de l’onde mécanique sur la chaîne des osselets en vue de la fenêtre ovale

- plongée de l’onde de pression dans la cochlée qui contient l’organe de l’audition relié au cerveau

Quantum Tunneling 

Quantum tunneling refers to the quantum mechanical phenomenon where a particle tunnels through a barrier that it classically could not surmount. This plays an essential role in several physical phenomena, such as the nuclear fusion that occurs in main sequence stars like the Sun. It has important applications to modern devices such as the tunnel diode, quantum computing, and the scanning tunneling microscope. The effect was predicted in the early 20th century and its acceptance as a general physical phenomenon came mid-century.

Tunneling is often explained using the Heisenberg uncertainty principle and the wave–particle duality of matter. Pure quantum mechanical concepts are central to the phenomenon, so quantum tunneling is one of the novel implications of quantum mechanics.

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WORKING ON CHRISTMAS: While the beautiful Earth looms in the background, astronaut Steven Smith stands on the mobile foot restraint at the end of the remote manipulator system as he makes repairs to the Hubble Space Telescope, Dec. 24-25, 1999. (NASA)

I visited Nantes’ Natural History Museum.

All the times science fiction became fact

I don’t usually go for these really-big-ads-disguised-as-infographics (Really? Sci-fi ink & toner?), but this one was too cool to pass up.

Unfortunately, no hoverboards yet. But we’ve still got 15 months before time runs out on that one:

Bonus: Why are some science fiction authors so good at predicting the future? Check out this episode of It’s Okay To Be Smart where I talk all about that:

(via io9)

Theories about the Origins of Space and Time. 1. Gravity as Thermodynamics Entropic gravity is a theory in modern physics that describes gravity as an entropic force - not a fundamental interaction mediated by a quantum field theory and a gauge particle, but a consequence of physical systems’ tendency to increase their entropy.  2. Loop Quantum Gravity According to Einstein, gravity is not a force – it is a property of space-time itself. Loop quantum gravity is an attempt to develop a quantum theory of gravity based directly on Einstein’s geometrical formulation. The main output of the theory is a physical picture of space where space is granular. More precisely, space can be viewed as an extremely fine fabric or network “woven” of finite loops. These networks of loops are called spin networks. The evolution of a spin network over time is called a spin foam. The predicted size of this structure is the Planck length, which is approximately 10−35 meters. According to the theory, there is no meaning to distance at scales smaller than the Planck scale. Therefore, LQG predicts that not just matter, but space itself, has an atomic structure. 3. Causal Sets Its founding principles are that spacetime is fundamentally discrete and that spacetime events are related by a partial order. The theory postulates that the building blocks of space-time are simple mathematical points that are connected by links, with each link pointing from past to future. Such a link is a bare-bones representation of causality, meaning that an earlier point can affect a later one, but not vice versa. The resulting network is like a growing tree that gradually builds up into space-time. 4. Causal Dynamical Triangulations The idea is to approximate the unknown fundamental constituents with tiny chunks of ordinary space-time caught up in a roiling sea of quantum fluctuations, and to follow how these chunks spontaneously glue themselves together into larger structures. The space-time building blocks were simple hyper-pyramids (four-dimensional counterparts to three-dimensional tetrahedrons) and the simulation’s gluing rules allowed them to combine freely. The result was a series of bizarre ‘universes’ that had far too many dimensions (or too few), and that folded back on themselves or broke into pieces. 5. Holography In this model, the three-dimensional interior of the universe contains strings and black holes governed only by gravity, whereas its two-dimensional boundary contains elementary particles and fields that obey ordinary quantum laws without gravity. Hypothetical residents of the three-dimensional space would never see this boundary, because it would be infinitely far away. But that does not affect the mathematics: anything happening in the three-dimensional universe can be described equally well by equations in the two-dimensional boundary, and vice versa.