Can't put it down...

This interesting biography of Rosalind Franklin is very hard to put down.

Lots of physics concepts set in the drama of a one woman's life. Excellent.

An interesting gamma ray burst during final exam week, GRB 130427A

An interesting gamma ray burst happened during finals week, GRB 130427A

Back in the early 1960s, the United States launched a few satellites, the Vela satellites, to detect secret nuclear weapons testing by the Soviet Union. By treaty between the US and USSR, no one was to test nuclear weapons above ground; underground testing was permitted. To monitor the Russians, US scientists at Los Alamos developed the Vela platform.

Nobody ever saw the Russkies nuking off any above ground tests, but while the detectors were not over Siberia, they could definitely see bursts of high energy gamma rays from sources outside the solar system.

Excellent.

In the 1970s, they began publishing scientific studies of these gamma ray bursters. The image below is an animation of the April 27 burst. Click the image to see the animation.

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There is still a lot of study going on as to why these GRBs happen all over the universe. We do not know for sure, and neither do the Russians. This GRB was so close and so well-imaged, that maybe someone will now crack the puzzle, using F = ma, quantum physics and all the concepts we study in PSC1121.

Next semester

Next semester, I will try to feature more biographical material on

1. Rosalind Franklin (DNA, xray diffraction)
2. Louis Pasteur (crystals, polarized light)
3. Michael Faraday (electromagnetic field, light)

Simplifying the grades page

I decided to simplify the grades page, by

1. removing the weight factors -- man, was that a mess;
2. pushing all the regular points from exam, HW and clicking into the "Regular points subtotal."

If you look at your regular points subtotal, you get an estimate of your semester grade, even though I have not added in bonus points yet. I am still fussing with bonus pointages but I will get them squared away as fast as possible.

Be patient, and keep alert, and we humans will defeat the machine known as Webcourses2.

Subtotals

I am updating a new row of your Grades page, "Regular points subtotal," which includes best two midterms, final exam, homework pointage and class participation iClicker 2 pointage.

I will be getting to the bonus points subtotal last.