Venus Aerospace has reached a major milestone. Courtesy photo
Houston-based Venus Aerospace successfully completed the first U.S. flight test of its proprietary engine at a demonstration at Spaceport America in New Mexico.
Venus’ next-generation rotating detonation rocket engine (RDRE) is supported by a $155,908 federal Small Business Innovation Research (SBIR) grant from NASA and aims to enable vehicles to travel four to six times the speed of sound from a conventional runway. The recent flight test was the first of an American-developed engine of its kind.
"With this flight test, Venus Aerospace is transforming a decades-old engineering challenge into an operational reality,” Thomas d'Halluin, managing partner at Airbus Ventures, an investor in Venus, said in a news release. “Getting a rotating detonation engine integrated, launch-ready, and validated under real conditions is no small feat. Venus has shown an extraordinary ability to translate deep technical insight into hardware progress, and we're proud to support their bold approach in their attempt to unlock the hypersonic economy and forge the future of propulsion."
Venus’ RDRE operates through supersonic shockwaves, called detonations, that generate more power with less fuel. It is designed to be affordable and scalable for defense and commercial systems.
The RDRE is also engineered to work with the company's air-breathing detonation ramjet, the VDR2, which helps enable aircraft to take off from a runway and transition to speeds exceeding Mach 6. Venus plans for full-scale propulsion testing and vehicle integration of this system. Venus’ ultimate goal is to develop a Mach 4 reusable passenger aircraft, known as the Stargazer M4.
"This milestone proves our engine works outside the lab, under real flight conditions," Andrew Duggleby, Venus co-founder and chief technology officer, said in the release. "Rotating detonation has been a long-sought gain in performance. Venus' RDRE solved the last but critical steps to harness the theoretical benefits of pressure gain combustion. We've built an engine that not only runs, but runs reliably and efficiently—and that's what makes it scalable. This is the foundation we need that, combined with a ramjet, completes the system from take-off to sustained hypersonic flight."
The hypersonic market is projected to surpass $12 billion by 2030, according to Venus.
"This is the moment we've been working toward for five years," Sassie Duggleby, CEO and co-founder of Venus Aerospace, added. "We've proven that this technology works—not just in simulations or the lab, but in the air. With this milestone, we're one step closer to making high-speed flight accessible, affordable, and sustainable."
Five Houston female founders have been recognized by Inc. Magazine for their innovation, including Sassie Duggleby, the CEO and co-founder of groundbreaking space tech and engine company Venus Aerospace.
The women were named to Inc.'s Female Founders 500 list, which features female entrepreneurs based in the U.S. The group attracted approximately $9 billion in 2024 revenue and $10.6 billion in funding, according to Inc.
“Female founders know what struggle is, but they’re also experts of improvisation, adaptability, and creativity. The women featured on this year’s list exemplify these qualities," Diana Ransom, Inc. executive editor said in a release. "Through times of uncertainty, their unwavering dedication and steadfast leadership are not only inspiring but vital to driving progress.”
Venus Aerospace is the Houston-based company that is developing reusable hypersonic technology that it hopes "will revolutionize and redefine the boundaries of aviation, defense, and beyond." The company won the in the Deep Tech Business category in the 2024 Houston Innovation Awards. Duggleby also serves on the Texas Space Commission board of directors.
Duggleby is joined by four other Houston founders:
Stephanie Murphy, CEO and executive chairman of Aegis Aerospace, which provides space services, spaceflight product development, and engineering services. Murphy also serves on the Texas Aerospace Research and Space Economy Consortium Executive Committee.
Emily Cisek, founder of The Postage, now known as Paige, a comprehensive life planning and succession software platform for families and small businesses. The company won the Female-Owned Business category in the 2023 Houston Innovation Awards.
Margo Jordan, founder of adolescent mental health startup Enrichly, which uses AI-driven self-esteem development and behavioral insights to boost student performance.
Nina Magon, founder of Nina Magon Studio / Nina Magon Consumer Products, a residential and commercial interior design company.
"While I don't know many of the ladies on this list, I do know they're some of the most tenacious role models in entrepreneurship. I'm beyond honored to be included among them," Duggleby said in a LinkedIn post.
Twenty-eight Texas female founders made this list, including Kendra Scott and Allison Ellsworth, co-founder of Poppi, and many others.
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A version of this story first appeared on our sister site, InnovationMap.com.
Venus Aerospace is one step closer to high-speed international travel. Photo courtesy Venus Aerospace
A Houston-headquartered hardtech company that's working on technology to enable hypersonic travel has announced a partnership with NASA to test its tech.
Venus Aerospace has partnered with NASA’s Marshall Space Flight Center in Huntsville, Alabama, on what is reportedly the longest sustained tests of a rotating detonation rocket engine, also known as an RDRE.
“Venus believes strongly in the performance step-change that RDREs bring for both hypersonic and space applications. The partnership with NASA has been key in maturing this new technology.” Andrew Duggleby, CTO and co-founder of Venus Aerospace, says in a news release.
The company's engine injector, which used regeneratively-cooled RDRE architecture, was tested in a "flight-like manner," according to the company. The technology operated successfully for 4 minutes of hotfire testing — a significant improvement, as engine tests of this type last for only 1 to 2 seconds, according to Venus.
"This long-duration hotfire means RDRE’s have retired a major risk area and are able to move into the few remaining steps before a flight demonstration," reads the press release from Venus.
As Venus continues to develop its technology for research, defense, and commercial missions, it will continue to work with NASA, which is also looking into RDRE technology for lunar and martian landers, in-space operations and logistics, and other deep space missions, per the release, because RDREs are more compact, efficient, and versatile than traditional rocket engines.
"Venus has entered into a second-year contract with NASA to provide engine parts for research and development of NASA’s RDRE," the news release continues. "In year two, NASA, with Venus’s support, will test different propellant combinations on hardware, to operate at even higher thrust levels and to demonstrate efficiency gains promised by the detonation engine."
Last summer, Venus added a new investor to its cap table. Andrew Duggleby founded Venus Aerospace with his wife and CEO Sarah "Sassie" Duggleby in 2020, before relocating to the Houston Spaceport in 2021. Last year, Venus raised a $20 million series A round.
At last year's awards program, Cemvita Factory's co-founders, Tara and Moji Karimi, accepted the award for the Green Impact Business category. This year, Moji Karimi served as a judge
The 2023 Houston Innovation Awards announced its 52 finalists — a large portion of which are promising energy transition startups.
The awards program — hosted by EnergyCapital's sister site, InnovationMap, and Houston Exponential — will name its winners on November 8 at the Houston Innovation Awards. The program was established to honor the best and brightest companies and individuals from the city's innovation community.
The following startups, which all have an energy transition element to their business, received a finalist position in one or two categories.
ALLY Energy, helping energy companies and climate startups find, develop, and retain great talent, scored two finalist positions — one in the Female-Owned Business category and the other in the Social Impact Business category.
Eden Grow Systems, next generation farming technologies, is a finalist in the People's Choice: Startup of the Year category.
Feelit Technologies, nanotechnology for preventive maintenance to eliminate leaks, fires and explosions, increase safety and reduce downtime, is a finalist in the Female-Owned Business category and the People's Choice: Startup of the Year category.
Fervo Energy, leveraging proven oil and gas drilling technology to deliver 24/7 carbon-free geothermal energy, scored two finalist positions — one in the Sustainability Business category and the other in the People's Choice: Startup of the Year category.
FluxWorks, making frictionless gearboxes for missions in any environment, is a finalist in the Hardtech Business category.
Helix Earth Technologies, decarbonizing the built environment and heavy industry, is a finalist in the Hardtech Business category.
INOVUES, re-energizing building facades through its non-invasive window retrofit innovations, making building smarter, greener, and healthier for a better and sustainable future, was named a finalist in the SustainabilityBusiness category.
Kanin Energy, helping heavy industry monetize their waste heat and decarbonize their operations, was named a finalist in the BIPOC-Owned Business and the SustainabilityBusiness categories.
Mars Materials, developing a carbon-negative pathway for carbon fiber and acrylamide production using CO2 and biomass as raw materials, is a finalist in the BIPOC-Owned Business category.
Molecule, an energy/commodity trading risk management software that provides users with an efficient, reliable, responsive platform for managing trade risk, is a finalist in the Digital Solutions Business category.
Rhythm Energy, 100 percent renewable electricity service for residential customers in Texas, is a finalist in the People's Choice: Startup of the Year category.
Sage Geosystems, a cost-effective geothermal baseload energy solution company, also innovating underground energy storage solutions, was named a finalist in the Sustainability Business category.
Solugen, decarbonizing the chemical industry, is a finalist in the Hardtech Business category.
Square Robot, applying robotic technology to eliminate the need to put people into dangerous enclosed spaces and eliminate taking tanks out of service, is a finalist in the HardtechBusiness category.
Syzygy Plasmonics, a deep decarbonization company that builds chemical reactors designed to use light instead of combustion to produce valuable chemicals like hydrogen and sustainable fuels, is a finalist in the HardtechBusiness category.
Tierra Climate, decarbonizing the power grid faster by helping grid-scale batteries monetize their environmental benefits and change their operational behavior to abate more carbon, was named a finalist in the SustainabilityBusiness category.
Utility Global, a technology company converting a range of waste gases into sustainable hydrogen and syngas, was named a finalist in the SustainabilityBusiness category.
Venus Aerospace, a hypersonics company on track to fly reusable hypersonic flight platforms by 2024, is a finalist in the HardtechBusiness category.
Additionally, two energy companies were named to the Corporate of the Year category, which honors corporations that supports startups and/or the Houston innovation community. Aramco Ventures and Chevron Technology Ventures are two of the four finalists in this category.
Lastly, Jason Ethier, co-founder of Lambda Catalyzer and host of the Energy Tech Startups podcast, and Kendrick Alridge, senior manager of community at Greentown Labs, scored finalist positions in the Ecosystem Builder category, as individuals who have acted as leaders in developing Houston’s startup ecosystem.
Houston maintained its No. 3 status this year among U.S. metro areas with the most Fortune 500 headquarters. Fortune magazine tallied 26 Fortune 500 headquarters in the Houston area, behind only the New York City area (62) and the Chicago area (30).
Last year, 23 Houston-area companies landed on the Fortune 500 list. Fortune bases the list on revenue that a public or private company earns during its 2024 budget year.
On the Fortune 500 list for 2025, Spring-based ExxonMobil remained the highest-ranked company based in the Houston area as well as in Texas, sitting at No. 8 nationally. That’s down one spot from its No. 7 perch on the 2024 list. During its 2024 budget year, ExxonMobil reported revenue of $349.6 billion, up from $344.6 billion the previous year.
Here are the rankings and 2024 revenue for the 25 other Houston-area companies that made this year’s Fortune 500:
Nationally, the top five Fortune 500 companies are:
Walmart
Amazon
UnitedHealth Group
Apple
CVS Health
“The Fortune 500 is a literal roadmap to the rise and fall of markets, a reliable playbook of the world's most important regions, services, and products, and an indispensable roster of those companies' dynamic leaders,” Anastasia Nyrkovskaya, CEO of Fortune Media, said in a news release.
Among the states, Texas ranks second for the number of Fortune 500 headquarters (54), preceded by California (58) and followed by New York (53).
Three Houston companies claimed spots on LexisNexis's 10 Most Innovative Startups in Texas report, with two working in the geothermal energy space.
Sage Geosystems claimed the No. 3 spot on the list, and Fervo Energy followed closely behind at No. 5. Fintech unicorn HighRadius rounded out the list of Houston companies at No. 8.
LexisNexis Intellectual Property Solutions compiled the report. It was based on each company's Patent Asset Index, a proprietary metric from LexisNexis that identifies the strength and value of each company’s patent assets based on factors such as patent quality, geographic scope and size of the portfolio.
Houston tied with Austin, each with three companies represented on the list. Caris Life Sciences, a biotechnology company based in Dallas, claimed the top spot with a Patent Asset Index more than 5 times that of its next competitor, Apptronik, an Austin-based AI-powered humanoid robotics company.
“Texas has always been fertile ground for bold entrepreneurs, and these innovative startups carry that tradition forward with strong businesses based on outstanding patent assets,” Marco Richter, senior director of IP analytics and strategy for LexisNexis Intellectual Property Solutions, said in a release. “These companies have proven their innovation by creating the most valuable patent portfolios in a state that’s known for game-changing inventions and cutting-edge technologies.We are pleased to recognize Texas’ most innovative startups for turning their ideas into patented innovations and look forward to watching them scale, disrupt, and thrive on the foundation they’ve laid today.”
This year's list reflects a range in location and industry. Here's the full list of LexisNexis' 10 Most Innovative Startups in Texas, ranked by patent portfolios.
Fervo Energy fully contracted its flagship 500 MW geothermal development, Cape Station, this spring. Cape Station is currently one of the world’s largest enhanced geothermal systems (EGS) developments, and the station will begin to deliver electricity to the grid in 2026. The company was recently named North American Company of the Year by research and consulting firm Cleantech Group and came in at No. 6 on Time magazine and Statista’s list of America’s Top GreenTech Companies of 2025. It's now considered a unicorn, meaning its valuation as a private company has surpassed $1 billion.
Meanwhile, HighRadius announced earlier this year that it plans to release a fully autonomous finance platform for the "office of the CFO" by 2027. The company reached unicorn status in 2020.
The climate conversation is evolving — fast. It’s no longer just about emissions targets and net-zero commitments. It’s about capital, infrastructure, and execution at industrial scale.
That’s exactly where Yao Huang operates. A seasoned tech entrepreneur turned climate investor, Yao brings sharp clarity to one of the biggest challenges in climate innovation: how do we fund and scale technologies that remove carbon without relying on goodwill or government subsidies?
In this episode of the Energy Tech Startups Podcast, Yao sits down with hosts Jason Ethier and Nada Ahmed for a wide-ranging conversation that redefines how we think about decarbonization. From algae-based photobioreactors that capture CO₂ at the smokestack, to financing models that mirror real estate and infrastructure—not venture capital—Yao lays out a case for why the climate fight will be won or lost on spreadsheets, not slogans.
Her message is as bold as it is practical: this isn’t about saving the planet for the sake of it. It’s about building profitable, resilient systems that scale. And Houston, with its industrial base and project finance expertise, is exactly the place to do it.
The 40-Gigaton Challenge—and a Pandemic Pivot
Yao’s entry into climate wasn’t part of a long-term plan. It was sparked by a quiet moment during the pandemic—and a book.
Reading How to Avoid a Climate Disaster by Bill Gates, she came to two uncomfortable realizations:
The people in power don’t actually have this figured out, and
She would be alive to suffer the consequences.
That insight jolted her out of the traditional tech world and into climate action. She studied at Stanford, surrounded herself with mentors, and began diving into early-stage climate deals. But she quickly realized that most of the solutions she was seeing were still years away from commercialization.
So she narrowed her focus: no R&D moonshots, no science experiments—just deployable solutions that could scale now.
Carbon Optimum: Where Algae Meets Infrastructure
That’s how she found Carbon Optimum, a company using algae photobioreactors to remove CO₂ directly from industrial emissions. Their approach is both elegant and economic:
Install algae reactors next to major emitters like coal and cement plants.
Feed the algae with flue gas, allowing it to absorb CO₂ in a controlled system.
Harvest the algae and convert it into valuable commodities like bio-oils, fertilizer, and food ingredients.
It’s a nature-based solution, enhanced by engineering. One acre of tanks can capture emissions and generate profit—without subsidies.
“This is one of the few solutions I’ve seen that can scale profitably and quickly,” Yao says. “And we’re not inventing anything new—we’re just doing it better.”
The Real Problem? It’s Capital, Not Carbon
As an investor, Yao is blunt: most climate startups are misaligned with the capital markets.
They’re following a tech startup playbook—built for SaaS, not steel. But building climate infrastructure requires a completely different approach: project finance, blended capital, debt structures, carbon credit integration, and regulatory incentives.
“Climate tech is more like real estate or healthcare than software,” Yao explains. “You don’t raise six rounds of venture. You build a stack—grants, equity, debt, tax credits—and you structure your project like infrastructure.”
It’s not just theory. It’s exactly how Carbon Optimum is expanding—through partnerships, offtake agreements, and real-world deployments. And it’s why she believes many climate startups fail: they don’t speak the language of finance.
Houston’s Role in the Climate Capital Stack
For Yao, Houston isn’t just a backdrop—it’s a strategic asset.
The city’s deep bench of project finance professionals, commodity traders, lawyers, and infrastructure veterans makes it uniquely positioned to lead the deployment phase of climate solutions.
“We’ve been calling it the wrong thing,” she says. “This isn’t just about climate—it’s an energy transition. And Houston knows how to build energy infrastructure at scale.”
Still, she notes, the ecosystem needs to evolve. Less education, more execution. Fewer workshops, more closers.
“Houston could be the epicenter of this movement—if we activate the right people and get the right projects over the line.”
From Carbon Capture to Circular Economies
The potential applications of Carbon Optimum’s algae platform go beyond carbon capture. Because the output—algae biomass—can be converted into:
Renewable oil
High-efficiency fertilizers (critical in today’s geopolitically fragile supply chains)
Food ingredients rich in protein and nutrients
Even biochar, a highly stable form of carbon sequestration
It’s scalable, modular, and location-agnostic. In island nations, Yao notes, these systems can offer energy independence by turning waste CO₂ into local energy and fertilizer—without needing to import fuels or food.
“It’s not just emissions reduction. It’s economic sovereignty through circular systems.”
Doing, Not Just Talking
One of Yao’s key takeaways for founders? Don’t waste time. Climate startups don’t have the luxury of trial-and-error cycles stretched over years.
“Founders need to get real about what it takes to scale: talent, capital, storytelling, partnerships. If you’re not ready to do that, maybe you should be a CSO, not a CEO.”
She also points out that founders don’t need to hire everyone—they need to tap the right networks. And in cities like Houston, those networks exist—if you know how to motivate them.
“It takes a different kind of leadership. You’re not just raising money—you’re moving people.”
Why This Episode Matters
This conversation is for anyone who’s serious about scaling real solutions to the climate crisis. Whether you’re a founder navigating capital markets, an investor seeking return and impact, or a policymaker designing the frameworks — Yao Huang offers a grounded, urgent, and actionable perspective.
It’s not about hope. It’s about execution.
Listen to the full episode of the Energy Tech Startups Podcast with Yao Huang:
-- Hosted by Jason Ethier and Nada Ahmed, the Digital Wildcatters’ podcast, Energy Tech Startups, delves into Houston's pivotal role in the energy transition, spotlighting entrepreneurs and industry leaders shaping a low-carbon future.