Dark matter is a mysterious form of matter which exerts gravitational effects on ordinary matter but cannot be observed via any other means. While conventional matter can be detected through stellar activity, light scattering, radio emissions, and other means, dark matter clouds are invisible to the vast majority of our instruments. Yet they constitute 90% – 99% of the matter in the universe.
Category Archive: Short Geoscience Articles
Permanent link to this article: http://www.explainstuff.com/2009/06/21/what-is-dark-matter-science-concept-of-the-day/
An Ice Age is a period of time, typically about 30 million years but occasionally as long as 300 million years, during which ice sheets cover at least the Earth’s polar areas. Individual Ice Ages have sub-Ice Ages, called glacials (when cold) or interglacials (when warmer) that operate in cycles of 40,000 and 100,000 years. When the term “Ice Age” is used colloquially, it often refers to these shorter glacials, periods when the ice caps extend significantly beyond the poles and into the hearts of continents such as North America and Eurasia.
Permanent link to this article: http://www.explainstuff.com/2009/06/15/ice-age-o/
Read about who invented Richter scale and when. Explain stuff takes you further than just the point of giving you a fact. Learn how a Richter scale works. What was the largest earthquake ever to be measured? Read further to learn how earthquakes are measured and using what scale. Also learn about what the ratings of earthquakes on a Richter scale mean.
Permanent link to this article: http://www.explainstuff.com/2009/05/10/explain-stuff-richter-scale-fact-of-the-day/