- Rubidium is a chemical element; it has symbol Rb and atomic number 37. It is a very soft, whitish-grey solid in the alkali metal group, similar to potassium and caesium. Rubidium is the first alkali metal in the group to have a density higher than water. On Earth, natural rubidium comprises two isotopes: 72% is a stable isotope 85Rb, and 28% is slightly radioactive 87Rb, with a half-life of 48.8 billion years – more than three times as long as the estimated age of the universe.
- Franklin Falls (waterfallsnorthwest.com)
Franklin Falls is the uppermost waterfall along the South Fork Snoqualmie River which bears an officially recognized name, as well as developed trail access. More uniquely the falls have the distinct characteristic of being situated in between the east and west lanes of Interstate 90, with the westbound lanes crossing a talus slope directly above the falls on a high viaduct. Compounding this surprisingly unobtrusive influence of man, the trail to the falls is among the most popular in the Snoqualmie Pass area thanks to its ease and kid-friendliness.