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Two perfect conducting spheres are immersed in a fluid with electrical conductivity σ = 5 x 10^-2 S/m. The spheres have radius r = 1 mm and are maintained a distance R = 1 m apart. A potential difference of V = 220 V is maintained between the two spheres. The fluid extends to infinity. Calculate the net current flowing between the spheres. (If you've been paying attention, you've noticed that this situation violates charge continuity.

As some of you know, I'm going back to the South Pole later this year in December/January. Preparing to go to Antarctica is an intensive process. Most of it relates to preparing the measurements and instrument upgrades we plan to make there. However, there's also a medical component. Antarctica is a "harsh continent" with high altitude (the effective pressure altitude at the South Pole is around 10,500 ft.), freezing cold, extreme aridity, and limited medical facilities.

Last week, members of the South Pole Telescope (SPT) collaboration reported the first detection of B-mode polarization in the Cosmic Microwave Background (CMB). Scientists have been searching for B-mode polarization for over a decade because it offers an opportunity to study all the matter in the Universe and the cause of the Big Bang.

[Note: This is the last in a series of posts adapted from emails I wrote while traveling to the South Pole for research in 2012--2013.]

This is the last entry from the South Pole. I just bag dropped for the flight back to McMurdo tomorrow (Jan. 4). The procedure here is even simpler than at McMurdo. The bag drop is at "Destination Zulu," the rear entrance of the station, so there's no need to drag bags outside. The cargo crew takes care of weighing so all you have to do is put a tag with your name on your bags and leave them there.