Sunday, February 12, 2012

Greetings..



Date of issue : 26 January 2011

Tuesday, February 7, 2012


Date of issue : 2 January 2012

Fraunhofer Lines : The Rainbow Lines

This stamp has been issued by Geraman Post to commemorate 225th anniversary of German physicist Joseph von Fraunhofer (1787–1826) . In physics (optics) , the Fraunhofer lines are a set of spectral lines named after Joseph von Fraunhofer The lines were originally observed as dark features (absorption lines) in the optical spectrum of the Sun.