Author Archives: Andrea

Lunar eclipse

A total lunar eclipse will be visible from almost everywhere on earth tomorrow night (March 3rd/4th, 2007). This site links to several webcasts and gives the beginning and ending times:

“The Moon encounters the penumbra, the Earth’s outermost shadow zone, at 20:18 Universal Time (UT). About thirty minutes later a slight dusky shading can be noticed on the leading edge of the Moon.

At 21:30 UT the Moon begins its entry into the innermost shadow zone, or umbra. For more than an hour a circular shadow creeps across the Moon’s face. At 22:44 UT, the Moon will lie completely within Earth’s dark shadow.[…]

Totality will end at 23:58 UT, when the moon’s leading edge exits the umbra. The moon will leave the umbra completely at 01:11 UT, and the eclipse will end at 02:23 UT when the moon makes its last contact with the penumbra.”

I just looked out of the window at the moon in an almost clear nightsky. If the weather is like this tomorrow, it’s going to be fun to watch the eclipse from the office without getting cold outside. ;-)

Did it ever occur to you that whenever a lunar eclipse occurs on earth, there’s a solar eclipse on moon at the same time because the earth blocks the sun? It never did to me even though I teach how eclipses work at least once every year, and my students usually come up with all sorts of interesting ideas and questions. Here’s a picture of what it would look like.

It’s a pity I only found out about the eclipse now, I would have liked to tell my students about it – I’m covering related topics in two of the three physics classes I teach at the moment (basic optics including lunar and solar eclipses in 8th grade, Kepler‘s laws of planetary motion in 11th grade).

How to play the piano

Ralf discovered Chuan C. Chang’s Fundamentals of Piano Practice. The book is also available at pianofundamentals.com. To quote the author:

“This web site provides free piano lessons, piano teaching material, and piano tuning instructions. You can learn piano up to 1000 times faster (!) compared to other methods (see Chapter One, IV.5). This is the first book ever written on how to practice at the piano. For hundreds of years, many teachers and other books taught you what techniques to acquire, but that is of little use unless you know how to acquire them quickly, as Mozart, Liszt, etc., did. You can download the entire book free using the links below.”

My last piano lesson was about 13 years ago… I’d really like to start playing again, but for now it’s not feasible to move my piano from my parents’ house to our current home. However, having a piano (or a similar instrument) at home is necessary in order to practise enough. I should really look into buying a used electric piano or something like that.

Travelling with little luggage

This site is probably going to be useful before my next trip: One Bag is Doug Dyment‘s advice on how to travel with just a carry-on bag (or just a small bag, in case you’re not going by plane) and what and how to pack. His site contains an annotated packing list. Dyment’s tips are useful even if one doesn’t want to pack quite so radically minimalistic as he does.

And for the even more minimalistic travelers Dyment links to Anders Ansar who challenges himself by taking zero bags on his trips, though he cheats somewhat by having big pockets sewn into his trousers.

Great photos

Two great photo links on MetaFilter today:

Georg Gerster aerial photography.
From his website:

“Georg Gerster was born in Winterthur, Switzerland, on April 30th, 1928 […]. Since 1956 he has been a freelance journalist specializing in science reporting and aerial photography. He has undertaken extensive visits to every part of the world, including Antarctica.”

Click on “Picture Gallery” in the left margin on his website to browse a gallery of his photos (direct linking does not seem to be working).

Seb-Przds mindbending photos.
Flickr user Seb Przd specialises in spherical panoramas and conformal mappings. Be sure to take a look at his Equirectangular and Stereographic Projections galleries as well. He explains his technique here.