A year after raising $3 million in seed funding, a Space City startup has closed its high-flying series A round to the tune of $20 million.

Venus Aerospace, which is working on a zero-carbon emission spaceplane that will enable one-hour global travel, closed its series A funding round led by Wyoming-based Prime Movers Lab. The firm has a few dozen breakthrough scientific companies in its portfolio, including another Houston-based, space-focused startup, Axiom Space. The round also saw participation from previous investors: Draper Associates, Boost, Saturn 5, Seraph Group, Cantos, The Helm & Tamarack Global.

Venus Aerospace was founded by Sarah "Sassie" and Andrew Duggleby, who serve as the company's CEO and CTO, respectively, in 2020 in California. The Texas A&M University alumni later moved the business into its current facilities in the Houston Spaceport.

"The U.S. is in the middle of a global race for hypersonic technology, and the breakthroughs being developed by Sassie, Andrew, and their team have numerous civilian and defense applications," says Prime Movers Lab General Partner Brandon Simmons in a news release. "Venus hit critical engine tests, vehicle design, and growth milestones that make me tremendously excited about the future of American hypersonic flight."

According to the release, the company will use the fresh funding on enhancing its three main technologies: a next-generation rocket engine, aircraft shape, and leading-edge cooling system, which allows for the Venus spaceplane to take off from existing spaceports.

"These recent advances in technology finally enable a spaceplane, a vehicle long imagined, but only now possible," says Andrew Duggleby in the release. "We will use this round of funding to get into flight testing and engine testing at Spaceport Houston. Bringing this technology forward into systems, drones and ultimately spaceplanes, it will take both new space veterans and bright new minds to solve. We've gone from impossible to hard, and this investment will allow us to knock down the next few steps."

The past year has represented significant growth for Venus, with developing contracts with the government and building out the company's team — and the company still has eight positions listed on its website. After building out and testing its technology, Venus also started a ground test campaign at Spaceport Houston.

"We are excited to continue our partnership with Prime Movers Lab and our other great investors. In the past year, with our initial funding, we have scaled from 3 people to 40. These are the world's best rocket scientists, engineers, and operators," says Sassie Duggleby in the release. "With this funding, we will continue to push forward toward our next technical milestones, hire great people, and scale our organization. We are excited to continue engineering the future of high-speed aviation."