The US Naval Observatory is a scientific agency that is part of the US Government.

It was established in the mid 1800′s, and focused on keeping the official time of the US, as well as calibrating chronometers for Navy ships. (A chronometer is an old navigation device that used stars + time to calculate global position.)

Today, the Naval Observatory still keeps the official time. You can get the time by calling 719-567-6742, 202-762-1069, or 202-762-1401. Or on the web at http://www.usno.navy.mil/.

The Naval Observatory is also the location of the official home of the Vice President, called Number One Observatory Circle.

The house located there was originally used as the residence for the superintendent of the Observatory.

In 1974, congress made the house the VP’s official residence. Before then, the VP had to provide their own house, or stay in hotels. The cost of security at private residences was becoming too expensive, so an official residence was proposed.

Source: wiki and this LA Times article, which predictably claims that Dick Cheney conspired to keep his house off of Google Earth (he didn’t).