Karl the Fog stayed away, allowing Bay Area skywatchers a chance to observe the Super Blue Blood Moon total lunar eclipse that occurred in the early hours of January 31. I get up early anyway on weekdays. My current workout … Continue reading
When the Cassini probe launched in 1997, some controversy followed it for the first part of its voyage. Probes heading to the outer solar system need a speed boost. Big chemical rockets are too impractical and expensive. Ion rockets, though … Continue reading
Ptolemy was an Egyptian-born Roman philosopher and scientist who lived around the First and Second centuries AD. He’s best known for the Ptolemaic System of the universe, an expansion of Aristotle’s view that the Earth laid at the center of … Continue reading