Category Archives: Science

Nuclear Power and Clean Energy

NPR News: California’s Last Nuclear Power Plant To Be Shut Down.

NPR All Things Considered: California To Close State’s Last Nuclear Power Plant.

I remember both the Chernobyl and the Fukushima nuclear disasters and have become much more wary about nuclear power since the latter happened. Japan uses the same kind of reactors that are used in German nuclear power plants, and the disaster there has shown that even if the core doesn’t melt down like it did in Chernobyl‘s graphite-moderated reactor, there’s still a lot that can go wrong even in a water-moderated reactor like the ones used in Japan and Germany (boiling water reactors, pressurized water reactors).

The German government ordered eight of the seventeen reactors to be shut down immediately after Fukushima, and the others will be shut down by the end of the year 2022 at the latest. A few kilometers from where I live is a nuclear power plant that I’ve visited with groups of students several times (in fact I just went two days ago), and while this is of course an interesting excursion, I won’t be sad to see it shut down by the end of 2018 at the latest.

I’m surprised that environmentalists count nuclear power as “clean” like solar and wind because no carbon dioxide is emitted, but what about the tons of radioactive waste? This is an unsolved probleme here in Germany, and I wonder about the situation in other industrial nations like the US, but also Japan or the rest of Europe. Has any country solved this problem for real?

A second moon

Jet Propulsion Lab/NASA: Small Asteroid Is Earth’s Constant Companion.

“A small asteroid has been discovered in an orbit around the sun that keeps it as a constant companion of Earth, and it will remain so for centuries to come.

As it orbits the sun, this new asteroid, designated 2016 HO3, appears to circle around Earth as well. It is too distant to be considered a true satellite of our planet, but it is the best and most stable example to date of a near-Earth companion, or “quasi-satellite.””

The picture of the orbit reminded me of my first (and second-to-last) programming project: During my first year of university I had to write a program that calculated orbits of a satellite influenced by the gravity of sun and earth, also known as three-body-problem. Even though I checked my work again and again, the stupid program wouldn’t turn out the right (periodic or chaotic) orbits, so I had to get an extension on the deadline for handing in the project. Took me two whole days to find the sign error.

And now you know why I hate programming. ;-)

Electric Train

Physics Girl: World’s Easiest DIY Electric Train.

These trains are so much fun! I’ve actually built one last year with students after I saw the instructions on a Swiss/German site that sells neodymium magnets:

Supermagnete.de: Der einfachste Elektrozug der Welt.

The hard part was finding copper wire without insulation, which doesn’t seem to be available in German hardware stores. If you try and build one, don’t be surprised if the battery runs out fast – it’s short-circuited by the coil, so the fun runs out after a short while.

If you need more inspiration, take a look at World’s Simplest Electric Train (2) by Amazing Science.