dwarf-signal lens
1Railway signal — Not to be confused with Railway signalling. A signal is a mechanical or electrical device erected beside a railway line to pass information relating to the state of the line ahead to train/engine drivers. The driver interprets the signal s… …
2North American railroad signals — Main article: North American railway signaling Baltimore and Ohio Railroad Color Position Light bracket masts at Magnolia, West Virginia North American railroad signals generally fall into the category of multi headed electrically lit units… …
3Glossary of rail terminology — Rail transport Operations Track Maintenance High speed Gauge Stations …
4Dark matter — Not to be confused with antimatter, dark energy, dark fluid or dark flow. For other uses, see Dark Matter (disambiguation) …
5Stars and planetary systems in fiction — The planetary systems of stars other than the Sun and the Solar System are a staple element in much science fiction. Contents 1 Overview 1.1 The brightest stars …
6Physical Sciences — ▪ 2009 Introduction Scientists discovered a new family of superconducting materials and obtained unique images of individual hydrogen atoms and of a multiple exoplanet system. Europe completed the Large Hadron Collider, and China and India took… …
7astronomy — /euh stron euh mee/, n. the science that deals with the material universe beyond the earth s atmosphere. [1175 1225; ME astronomie ( < AF) < L astronomia < Gk. See ASTRO , NOMY] * * * I Science dealing with the origin, evolution, composition,… …
8literature — /lit euhr euh cheuhr, choor , li treuh /, n. 1. writings in which expression and form, in connection with ideas of permanent and universal interest, are characteristic or essential features, as poetry, novels, history, biography, and essays. 2.… …
9Life Sciences — ▪ 2009 Introduction Zoology In 2008 several zoological studies provided new insights into how species life history traits (such as the timing of reproduction or the length of life of adult individuals) are derived in part as responses to… …
10Methods of detecting extrasolar planets — Any planet is an extremely faint light source compared to its parent star. In addition to the intrinsic difficulty of detecting such a faint light source, the light from the parent star causes a glare that washes it out. For those reasons, only a …
