Alexander Dahl was a German

Germany

Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...

 industrialist, author

Author

An author is broadly defined as "the person who originates or gives existence to anything" and that authorship determines responsibility for what is created. Narrowly defined, an author is the originator of any written work.-Legal significance:...

 and balloonist. He was the first person to take a photograph of the Earth's curvature from an open hydrogen gas balloon in 1933.

First photograph of Earth's curvature

The first image showing the Earth's curvature was taken at a height of 11300m on 31 August 1933 from the high performance (9.800 cbm) hydrogen gas balloon Bartsch von Sigsfeld. The official purpose of the flight was not to gain maximum height, but rather to measure the effect of sun radiation within the tropopause

Tropopause

The tropopause is the atmospheric boundary between the troposphere and the stratosphere.-Definition:Going upward from the surface, it is the point where air ceases to cool with height, and becomes almost completely dry...

. However, as part of the flight, the crew also set the first height record for unaided altitude flight in an open air balloon.