Saturday, March 27, 2010
Sunday, March 21, 2010
In 1990, when Voyager I spacecraft was leaving the solar system, NASA commanded the robotic space probe to turn its camera towards Earth and take a picture of the planet. The picture, taken from a distance of 6 billion kilometers, came to be known as “the pale blue dot”. Viewed from such a remote vantage point, our planet seemed to be an insignificant dot against the vastness of space.
The two videos that I selected for this post deal with different facets of this apparent insignificance when it comes to understanding our place in the universe. Both approaches are very interesting.
Saturday, March 20, 2010
Ignaz Semmelweis, a hungarian obstetrician who lived in the 19th century, is nowadays credited with being the father of infection control. In his time, however, his propositions faced harsh skepticism and he was eventually forced to quit medicine altogether. In the end, he died in an institution for mentally ill patients.
As long as pathogens were not yet known, it is hardly surprising that his claims were not taken seriously. Just try to imagine how crazy they must have sounded.
This case is a good example of an apparently weird idea that was actually right. Although most seemingly ridiculous ideas regarding natural and human sciences are indeed no more than ridiculous ideas, there are some that turn out to be correct. For this reason, no ideas should be considered invalid a priori. This, of course, does not mean that they should be accepted a priori, as it is frequently the case with myths and pseudoscientific claims.
On the videos below you will come into contact with some controversial ideas that contradict commonly held assumptions, beliefs and theories. I do not necessarily agree with them. My purpose here is to stimulate reflection and critical thinking.
UNHEALTHY "HEALTHY" FOOD
Saturday, March 6, 2010
Solar power plants are one of the most cherished renewable energy sources. They are clean and the “raw material” they work with is available for free. However, they have some obvious limitations: they cannot generate power at night*, the solar panels generally occupy huge areas and their effectiveness depends on climate conditions.
Fortunately there may be another way to profit from nuclear reactions such as those that take place in a star. For decades, scientists have been trying to use these reactions to generate electrical power. Nevertheless, until recently, they did not succeed to produce a nuclear fusion reaction that produced more energy than it consumed.
Now it seems to have finally happened. Watch the video below and find out how.
* ERRATA: Actually, part of the thermal energy collected during daytime can be stored and used to generate electrical power at night. This, nevertheless, does not change the fact that the total amount of energy produced each day is limited by the partial absence of sunlight.