- The Hertzsprung–Russell diagram (abbreviated as H–R diagram, HR diagram or HRD) is a scatter plot of stars showing the relationship between the stars’ absolute magnitudes or luminosities and their stellar classifications or effective temperatures. The diagram was created independently in 1911 by Ejnar Hertzsprung and by Henry Norris Russell in 1913, and represented a major step towards an understanding of stellar evolution.
- Yakima River (Wikipedia)
The Yakima River is a tributary of the Columbia River in south central and eastern Washington state, named for the indigenous Yakama people. Lewis and Clark mention in their journals that the Chin-nâm pam (or the Lower Snake River Chamnapam Nation) called the river Tâpe têtt (also rendered Tapteete), possibly from the French tape-tête, meaning “head hit”. The length of the river from headwaters to mouth is 214 miles (344 km), with an average drop of 9.85 feet per mile (1.866 m/km). It is the longest river entirely in Washington state.
