Tumbleweed Raises $7.7 Million to Develop Microgravity Research and Reentry Vehicle

Vienna-based startup Tumbleweed has raised €6.9 million (approximately $7.7 million) in a seed funding round to expand its microgravity research services and develop a spacecraft capable of returning materials from orbit to Earth.

The round was led by Pact VC , with participation from EWOR, Vanagon, Prototype Capital, ESA BIC Austria, Bernhard Rothenbuchner, Candace Johnson and other angel investors.

The funding follows the company’s first in-space mission in July 2026, when its Oasis Alpha satellite carried microgravity research payloads for four customers aboard a SpaceX rideshare. The mission marked the launch of Austria’s first commercial satellite.

Since then, Tumbleweed says it has seen growing interest from organizations seeking access to microgravity research without having to develop and operate their own spacecraft.

A significant portion of the new capital will go toward developing Oasis Beta, a reentry vehicle designed to bring materials manufactured or studied in microgravity back to Earth.

The company plans to begin Oasis Beta missions in 2028, targeting industries such as pharmaceuticals, semiconductors and photonics, where returning physical samples is essential to evaluating the results of experiments conducted in space.

Tumbleweed is also planning additional missions ahead of Oasis Beta's debut, with three flights booked for 2027, including both suborbital and orbital missions.

CEO Julian Rothenbuchner has positioned the company as an infrastructure provider serving industries beyond the traditional space sector.

The company joins a growing group of European and international startups developing commercial microgravity and return-to-Earth capabilities, including Germany’s ATMOS and U.S.-based Varda Space Industries.

Image Credits: Tumbleweed