Author: Ibrahim

Cassini – An exhilarating story of planetary exploration

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For more information: Cassini at Saturn

More on the Grand Finale (2nd dive: May 2, 2017; End of mission: Sept 15, 2017)

Animation of the Heat Diffusion in an L-shaped domain

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\partial_t T = K \partial^2_x T

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Animation of the Italy Earthquake’s Seismic Velocity

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A “real-time” animation of the seismic (vertical) velocity of Italy’s 5.5 Mw earthquake that hit between the Aquila and Rieti provinces. The second half of the animation shows the whole country and surrounding area.

Real-time indicates that the video reflects how the waves propagated in real-time. It’s neither slowed down not sped up.

Red color indicates relatively higher vertical velocities indicating the ground is moving upwards while the blue color indicates the lower (negative) velocities indicated a downward movement of the ground. Color intensity refers to the magnitude.

Fluid Mechanics video lectures

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In a previous post we selected some resources on fluid dynamics. In that post we suggested the videos from the National Committe for Fluid Mechanics (notes on the website) that date to the 1960’s and is an excellent exposition to fluid mechanics. We share them below following a very clear demonstration of Euler’s equation and Bernoulli’s integral:

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Sound of the Moving Earth

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What do you think an earthquake would sound like if you could hear it?

Here’s a sample (opens in a new tab).

The audio was generate by processing seismic data.

More samples are available on from the source where you can also find the corresponding spectrograms, (i.e. the representation of the frequency content of the signal and how it varies in time).

via Zhigang Peng @ Georgia Institute of Technology

Credit: Peng, Z., C. Aiken*, D. Kilb, D. Shelly, B. Enescu (2012), Listening to the 2011 magnitude 9.0 Tohoku-Oki, Japan earthquake, Seismol. Res. Lett., 83(2), 287-293, doi: 10.1785/gssrl.83.2.287. , and Kilb, D., Z. Peng, D. Simpson, A. Michael and M. Fisher* (2012), Listen, watch, learn: SeisSound video products, Seismol. Res. Lett., 83(2), 281-286, doi: 10.1785/gssrl.83.2.281.

As a follow-up here’s a nice video from USGS