Question: What do Sigmund Jähn and Piers Sellers have in common?

Context paragraphs:
Kue cubit: Kue cubit is a common snack food in many Indonesian cities.  It is a cake, around 4 cm in diameter.  The sellers of this snack usually operate near schools or traditional markets.  Kue cubit uses flour, baking powder, sugar and milk as its primary ingredients.  The liquid dough is poured into a steel plate with several small round basins so that it will form a round shape when cooked, and poured with "meises" (chocolate sprinkles) on top of it.  The sellers usually use a special hooked stick to take the cake off from the steel plate.

Grades and standards: In United States agricultural policy, grades and standards refers to the segregation, or classification, of agricultural commodities into groupings that share common characteristics.  Grades provide a common trading language, or common reference, so that buyers and sellers can more easily determine the quality (and therefore value) of those commodities.

The Fiendish Plot of Dr. Fu Manchu: The Fiendish Plot of Dr. Fu Manchu is a 1980 comedy film, primarily notable as the final film of Peter Sellers, David Tomlinson and John Le Mesurier.  Pre-production began with Richard Quine as director.  By the time the film entered production, Piers Haggard had replaced him.  Peter Sellers handled the re-shoots himself.  Based on characters created by Sax Rohmer, the film stars Sellers in the dual role of Fu Manchu, a stereotypical Chinese evil genius, and English country gentleman detective Nayland Smith.  Released only two weeks after Sellers death, the film was a commercial and critical failure.  It was also the final screen appearance for Tomlinson, who retired from acting shortly before its release.

Winona Church and School: The Winona Church and School is a historic church on Rockhouse Road in Winona Township, Carroll County, Arkansas.  The building, a single story wood frame structure with a gable roof, weatherboard siding, and modest Greek Revival styling, was built c. 1890 for use as both a school and a church, a common regional practice of the time.  It originally had a small pyramidal belfry, but the bell was stolen and the belfry removed when the roof was replaced.  Other alterations include the replacement of the old stone piers with concrete piers as its foundation.

Piers Sellers: Piers John Sellers OBE (11 April 1955 – 23 December 2016) was a British-American meteorologist, NASA astronaut and Director of the Earth Science Division at NASA/GSFC.  He was a veteran of three space shuttle missions.

Stefan Walz: Stefan Walz (born 1963) is a Swiss actor.  His best known role is as Sigmund Jähn in the film "Good Bye, Lenin! ".

Eberhard Köllner: Eberhard Köllner (born 29 September 1939 in Stassfurt, Germany) was selected for Soyuz 31 as the backup for Sigmund Jähn.

Ulf Merbold: Dr. Ulf Dietrich Merbold (born June 20, 1941) is the first West German citizen and second German native (after Sigmund Jähn) to have flown in space.  He is also the first member of the European Space Agency Astronaut Corps to participate in a spaceflight mission and the first non-US citizen to reach orbit in a US spacecraft.  In 1983, he and Byron Lichtenberg became the first Payload Specialists to fly on the shuttle.

Sigmund Jähn: Sigmund Werner Paul Jähn (born 13 February 1937) is a German cosmonaut and pilot, who in 1978 became the first East German (and German native) to fly in space as part of the Soviet Union's Interkosmos programme.

Ticket resale: Ticket resale (also known as ticket scalping or ticket touting) is the act of reselling tickets for admission to events.  Tickets are bought from licensed sellers and are then sold for a price determined by the individual or company in possession of the tickets.  Tickets sold through secondary sources may be sold for less or more than their face value depending on demand, which tends to vary as the event date approaches.  When the supply of tickets for a given event available through authorized ticket sellers is depleted, the event is considered "sold out", generally increasing the market value for any tickets on offer through secondary sellers.  Ticket resale is common in both sporting and musical events.

Supporting paragraphs: Sigmund Jähn Piers Sellers
Answer: astronaut