Measure Yourself Tonight and Again Tomorrow
The effect is large enough to find with a pencil mark on a door frame, which is the only reason anybody believes it without…
There is a fact almost everybody knows and almost nobody can explain, which makes it a useful place to start.
The Moon presents the same face to Earth continuously. The…
There is a question that sounds unanswerable and turns out to be a geometry problem.
How far away is a star? You cannot go there. You cannot bounce anything off…
Almost nobody looks at a dark night sky and thinks it requires explanation. It is dark because the sun has set, which seems sufficient.
It is not sufficient, and noticing…
Source: Wikipedia
Antarctica has around four hundred known subglacial lakes: bodies of liquid water trapped beneath kilometres of ice, kept from freezing by geothermal heat from below and the insulating weight…
Source: Wikipedia
The Voyager probes launched in 1977 to study the outer solar system, and they did that job extraordinarily well, returning the first detailed images of Jupiter, Saturn, Uranus and…