01 January, 1999 – The Euro becomes the official currency in 11 countries

While the Euro was already valid for bank transfers, notes and coins were introduced on January 1, 2002.

02 January, 1860 – Urban Le Verrier announces the discovery of the planet Vulcan

 Despite a thorough search, the planet was never actually sighted.

03 January, 1957 – The first electric watch is available

The Hamilton Electric 500 came in “modern” asymmetrical designs to reflect the revolutionary technology.

04 January, 2010 – Burj Khalifa is opened

Burj Khalifa in Dubai is currently the world's tallest building, at 829.8 m (2,722 ft).

05 January, 1933 – Construction of the Golden Gate Bridge begins

The Golden Gate Bridge in San Francisco is one of the best-known symbols of the United States.

06 January, 1970 – The Wiener Musikverein is inaugurated

The famous concert hall is the home of the Vienna Philharmonic Orchestra.

07 January, 1610 – Galileo Galilei discovers the Galilean Moons

The Italian astronomer spotted the four largest moons of Jupiter that day: Io, Europa, Ganymede, and Callisto.