- When redirects are implemented, change to a standard URL for Wikimedia-hosted pictures.
- Closeup of the side of railroad car 55 at Heritage Park in Lynnwood, Snohomish County, Washington. The top of the railroad car is painted white and has square windows, which are reflecting back leafless trees and blue sky. The middle of the train is pained in light blue with a red border, and has the number 55 in white paint. The bottom of the train has dark gray metallic wheels.
- Main sequence (Wikipedia)
In astronomy, the main sequence is a classification of stars which appear on plots of stellar color versus brightness as a continuous and distinctive band. Stars on this band are known as main-sequence stars or dwarf stars, and positions of stars on and off the band are believed to indicate their physical properties, as well as their progress through several types of star life-cycles. These are the most numerous true stars in the universe and include the Sun. Color-magnitude plots are known as Hertzsprung–Russell diagrams after Ejnar Hertzsprung and Henry Norris Russell.
