News

A ‘generationally defining moment’: 40 years later, NASA alum reflects on Challenger disaster

Jeff Zehnder — Mon, 26 Jan 2026 15:01:55 +0000

A ‘generationally defining moment’: 40 years later, NASA alum reflects on Challenger disaster Jeff Zehnder Mon, 01/26/2026 - 08:01

On January 28, 1986, NASA’s Challenger space shuttle disintegrated 73 seconds after launching from the Kennedy Space Center. All seven crew members aboard, including CU ��ý�� alumnus Ellison Onizuka (AeroEngr ’69), tragically lost their lives.

David Klaus, professor emeritus from CU ��ý��’s Ann and H.J. Smead Department of Aerospace Engineering Sciences, started his career with NASA and was a shuttle launch control engineer at the time (although he did not work the Challenger mission).

CU ��ý�� Today spoke with Klaus about his memories of that day, the legacy of the crew and crucial lessons learned from the tragedy.

Where were you on the day of the Challenger incident?

NASA had plans to start launching Air Force payloads off the West Coast at Vandenberg Air Force Base in California in July of 1986. I was training to be on the Vandenberg launch team, and I would have been on the Challenger launch console, but I had just gone out to California for some work out there. So I was at the Vandenberg launch site when the Challenger launched from the Kennedy Space Center in Florida.

We happened to be sitting in the launch control center at Vandenberg. We pretty much saw what everybody else watching TV saw, although we could hear the comms loops. We could hear what was going on.

When did you realize that something was wrong?

All I saw was that infamous image with the solid rocket boosters going off in two directions. I was pretty new in the game at that point, so I didn't have a lot of insight. But I was sort of in disbelief at first. You don't really comprehend what you're seeing. It just doesn't look right. Something looks wrong. Your brain’s trying to process what's going on. But we realized pretty quickly that this was a bad event.

What caused the shuttle to break apart?

The actual root cause of the failure was the O-rings (gaskets) that keep the propellant pressure contained inside the two rockets. It was really cold in Florida that day, and my understanding is that the cold weather made the seals brittle. Because they were brittle, they allowed gas pressure to escape, and the escaping gas pressure is ultimately what caused the destruction of the vehicle.

The Challenger crew members are pictured in November 1985, about two months before the tragedy. Back row, from left: Ellison Onizuka, Sharon McAuliffe, Greg Jarvis and Judy Resnik. Front row, from left: Michael Smith, Dick Scobee and Ron McNair. (Credit: NASA)

What lessons were learned from the Challenger?

For every NASA mission, when something goes wrong or is unexpected, it gets documented as ‘lessons learned’, and you work to make sure it doesn't happen again. You either change operational requirements, or you change the design, or both.

After the Challenger accident, for example, NASA has had tighter weather criteria for launch. And they added heater strips around the O-ring joints on later flights as part of a redesign. So both operational and design changes were made.

It's a high-risk endeavor to start with, putting people into space. And I think it became very apparent at that point. The Challenger was the first in-flight fatal accident that had occurred in NASA's history. In the space domain, there are a lot of unknown unknowns, and those are the ones that can cause the biggest problem. But once they happen, they're not unknown anymore, and now you've got something you can design toward.

How do you view the legacy of the Challenger crew?

The Challenger incident was one of those generationally defining moments. It was a reminder that life is risky. If you're pushing the envelope, you accept the risks, and you do the best you can to mitigate those risks. But you can't ever make them go away. So the crew’s legacy was maybe a heightened awareness of the risk of space flight, but also the importance of continuing to go to space even when catastrophic events do occur.

Looking back 40 years later, what stands out the most about the Challenger?

The technical lessons learned made me start thinking more about risk analysis. It's one thing to design a vehicle that can meet all the needs and do the job, but once you get to that point in the design process, you now go back and start looking at it and saying, ‘What can go wrong? What happens if it goes wrong, and what can we do about it if it does go wrong?’

The human aspect, of course, goes without saying. These were some pretty outstanding individuals, and their lives were tragically cut short. But on the other hand, I don't think they would have stepped aside. Everyone understood that there was risk. The degree of risk might have been debatable, but anytime you're launching people into space—anytime you're walking across the street, for that matter—there's a degree of risk that you accept in your life to do what you want to do.

David Klaus

If you were speaking to young engineers now, what would you want them to understand?

When you're the one designing the rockets or the habitats or any of the infrastructure, pay attention to the details. Don't take shortcuts. Try to think beyond just ‘Here's an answer that's good enough.’

Consider risk analysis from the very beginning of the design. Think about all the things that can go wrong and try to design something that is what we call either fault tolerant or redundant. So, if something breaks, can the system continue working? Or do you have another way that you can provide that function in place of the thing that broke?

Think about what needs to be done and break it down into the functions that have to be accomplished to make that happen. Then brainstorm different ideas—not just one solution, but as many as you can come up with. And then work to find an optimal balance of risk and complexity from that process.

Off

Traditional

White

Alumna set for New Shepard launch

Jeff Zehnder — Wed, 21 Jan 2026 17:09:37 +0000

Alumna set for New Shepard launch Jeff Zehnder Wed, 01/21/2026 - 10:09

Laura Stiles (AeroEngr MS'11, PhD'13) is spacebound.

The CU ��ý�� alumna is set to fly on the New Shepard Mission NS-38 suborbital flight, which is scheduled to launch Jan. 22, 2026.

Stiles is Blue Origin’s Director of New Shepard Launch Operations. She is a late addition to the flight, after a previously announced crew contracted an illness and is no longer able to fly.

Stiles has been at Blue Origin in 2013 where she has worked in a number of capacities, including mechanical systems design, integrated vehicle test, launch operations, astronaut training, as well as service as a Flight Controller and CapCom.

In 2024, Stiles was a recipient of a Smead Aerospace alumni award for Excellence in Technical Achievement and Leadership (Under 40 Category).

With the flight, Stiles will become the 21st CU affiliate to journey to space.

Off

Traditional

White

Skyward Showcase 2026 - Coming Friday, Feb. 20 - Sign up Now!

Jeff Zehnder — Wed, 21 Jan 2026 15:21:15 +0000

Skyward Showcase 2026 - Coming Friday, Feb. 20 - Sign up Now! Jeff Zehnder Wed, 01/21/2026 - 08:21

The Smead Program Presents
Skyward Showcase

Friday, February 20, 2025
@ The Aerospace Building
9 a.m. - 5 p.m. - Come and go throughout the day!

Research Talks! Prizes for presenters! Free Food!

Join us for this yearly tradition! Skyward Showcase provides Smead Aerospace students and faculty the opportunity to give 10-minute talks highlighting current research in a friendly and informal event

Questions? Sarah.Kinney@colorado.edu

Join us for this yearly tradition! Skyward Showcase provides Smead Aerospace students and faculty the opportunity to give 10-minute talks highlighting...

Off

Traditional

White

Boyd interviewed on potential sonic weapons

Jeff Zehnder — Thu, 15 Jan 2026 20:40:30 +0000

Boyd interviewed on potential sonic weapons Jeff Zehnder Thu, 01/15/2026 - 13:40

Iain Boyd discusses the raid to capture Nicolas Maduro in a new interview with The Telegraph (UK).

Boyd, a professor in the Ann and H.J. Smead Department of Aerospace Engineering Sciences, is a national security expert and also the director of the CU ��ý�� Center for National Security Initiatives.

The article explores if the United States used a sonic weapon as part of the raid. Such instruments are associated with the Havana Syndrome, a mysterious ailment that has impacted American diplomats around the world.

Boyd suggests the weapon used in the Maduro raid could have combined sonic and radio waves, but many questions remain.

Read the full story at The Telegraph...

Off

Traditional

White

Retired professor and astronaut honored

Jeff Zehnder — Fri, 09 Jan 2026 19:51:28 +0000

Retired professor and astronaut honored Jeff Zehnder Fri, 01/09/2026 - 12:51

Joe Tanner, NASA astronaut and former senior instructor at the ��ý�� is being inducted into the Astronaut Hall of Fame.

Tanner flew on four Space Shuttle missions from 1994 to 2006, taking part in Hubble Space Telescope servicing missions and critical assembly work on the Interntional Space Station.

After retiring from NASA, he joined the Ann and H.J. Smead Department of Aerospace Engineering Sciences, where he served as a senior instructor for nearly a decade.

The U.S. Astronaut Hall of Fame was created by the original Mercury Seven astronauts to recognize accomplishments in space and contributions to space exploration.

Read the full article at Space Coast Daily...

Off

Traditional

White

Minton interviewed on ablative materials research

Jeff Zehnder — Thu, 04 Dec 2025 20:49:45 +0000

Minton interviewed on ablative materials research Jeff Zehnder Thu, 12/04/2025 - 13:49

Tim Minton standing by a vacuum chamber in his laboratory.

Tim Minton was interviewed for a new piece in Via Satellite about research and opportunities in Very Low Earth Orbit (VLEO), the region between 250 and 400 kilometers above Earth's surface.

Minton, a professor in the Ann and H.J. Smead Department of Aerospace Engineering Sciences, is an expert on the degradation and ablation of materials in low-Earth-orbital and atmospheric-entry environments.

He spoke to the trade publication about his work in mitigating the corrosive effect of atomic oxygen atmosphere on satellite systems.

“Having both resistance to atomic oxygen and low drag is essential if we’re to increase the lifetime of satellites in VLEO," Minton said.

Read the full article at Via Satellite...

Tim Minton was interviewed for a new piece in Via Satellite about research and opportunities in Very Low Earth Orbit (VLEO), the region between...

Off

Traditional

White

Postdoc working on AI for astronauts

Jeff Zehnder — Mon, 01 Dec 2025 15:54:12 +0000

Postdoc working on AI for astronauts Jeff Zehnder Mon, 12/01/2025 - 08:54

Jeff Zehnder

Ulubilge Ulusoy is advancing the science of artificial intelligence to help astronauts on future missions to Mars.

Although such a flight is years away, AI systems will be critical to assisting astronauts as they journey beyond Earth’s orbit.

“These are problems we need to understand now,” Ulusoy said. “The International Space Station works because we have a huge group of humans in ground control helping these systems to function. When you go to Mars and the time delays for communications can be up to 24 minutes one way, it’s impossible for NASA to check things in real time. You need AI-based systems ready to keep the crew alive and the habitat functional.”

Ulusoy is designing methods to test human responses to AI systems within a framework where AI systems assist humans and humans also assist AI. The goal is to better understand how people can best interact with them.

He is the inaugural Smead Distinguished Postdoctoral Associate at the ��ý��. The one-year position provides funding for leading PhD graduates conducting aerospace research.

Ulusoy uses sensors to collect an array of physiological data as humans interact with AI systems in real-time, including heart rate variation, perspiration, breathing rate, and cognitive load.

Such objective data can reveal how trustworthy and useful human users find AI systems as well as the best methods AI can use to provide assistance.

“These systems are getting better, but we often ignore them anyway. You sometimes have Siri or Google pop up to say something and you’re like, ‘Not now, Siri.’ These new AI systems have machine learning technology so when you provide counter feedback, it can learn from that,” he said.

Ulusoy is conducting pilot tests this semester with the hope of beginning human trials in the spring. He and fellow Postdoctoral Associate Patrick Pischulti are working with Katya Arquilla, an assistant professor in the Ann and H.J. Smead Department of Aerospace Engineering Sciences, and an expert on how humans interact with and adapt to complex systems.

The research is a long-time goal of Ulusoy. He first began working on AI/astronaut interactions in 2020 during his PhD program. At that time, its potential was largely theoretical.

“I wanted to present a framework on paper, but in my third year, commercial, off-the-shelf large language models came out. It is a really exciting time to move forward,” he said.

The experiments this spring will see human test subjects working with a robotic arm to complete a physical task. Ulusoy will monitor the human test subject responses to see how well they work together.

“Being able to do human factors work, specifically collective physiological data is really helpful,” he said. “Implementing real-time, objective measurements will bring this to the next level.”

Off

Traditional

White

Knipp discusses auroras with the L.A. Times

Jeff Zehnder — Fri, 21 Nov 2025 17:04:20 +0000

Knipp discusses auroras with the L.A. Times Jeff Zehnder Fri, 11/21/2025 - 10:04

Delores Knipp was interviewed by the Los Angeles Times for a new article spotlighting the recent appearance of the Northern Lights in surprisingly low latitude locations.

Knipp, a research professor in the Ann and H.J. Smead Department of Aerospace Engineering Sciences, is an expert on solar wind-geospace coupling and space weather. She has also written extensively about historic solar storms.

The aurora borealis was recently strongly visible across Colorado. The L.A. Times was interested in its presence even further south -- in the Lost Angeles Metro area, where it has also been occasionally visible over the last year.

The article has good tips for spotting auroras across the United States, not just in Los Angeles.

Read it at the L.A. Times...

Off

Traditional

White

Space law – Influencing policy for low Earth orbit and beyond

Jeff Zehnder — Tue, 11 Nov 2025 16:00:07 +0000

Space law – Influencing policy for low Earth orbit and beyond Jeff Zehnder Tue, 11/11/2025 - 09:00

Jeff Zehnder

��ý�� researchers have been shaping space exploration for decades and now are expanding into space law.

As more nations launch satellites, space probes, and military hardware into orbit, policy has become an increasingly critical field in the U.S. and beyond.

Marcus Holzinger is a professor in the Ann and H.J. Smead Department of Aerospace Engineering Sciences and the inaugural holder of the Hatfield Endowed Professor in Space Policy & Law, a position created to shape the future of legal frameworks for space and serve as a bridge between academic research and real-world governance.

“The university brings a nonpartisan, technical perspective to the table, which is incredibly important,” Holzinger said. “When you’re talking about aircraft policy, where they fly, how high and how low, you wouldn’t want to make those decisions without anyone who knew how an airplane worked. We want to provide that necessary information to form cogent policy, but for space.”

CU ��ý�� also recently created the Colorado Space Policy Center to bring together academic majors across the university and further boost research and engagement in industry, civil, and military space. It is being led by Dan Baker, who served as director of the Laboratory for Atmospheric and Space Physics for nearly 30 years.

“We have one of the best concentrations of space scholars in the nation,” Holzinger said. “There’s also a very large space industry here in Colorado. There are a lot of people interacting across academia, industry, and government. This is the right place, at the right time, with the right people.”

CU ��ý�� already teaches non-engineering courses on space policy and has a Space Law Society for students. In addition, the aerospace department has revised its PhD practicum requirements to offer a policy option.

“Traditionally the practicum has been mentoring or teaching. We changed that so students could fulfill it by applying their technical skills to benefit society. We’ve now had students do that by interning at the state legislature, in federally funded research and development centers,
and at think tanks,” Holzinger said.

He is hoping to further integrate students into the space policy sphere. The Hatfield Professorship only began in June 2025, but Holzinger said he has already been contacted by many students interested in learning more about space policy.

“I’m really excited overall about the work being done here,” Holzinger said. “We’re drawing upon CU ��ý��’s technical expertise and strengths to be a real center of mass and resource for policymakers, through the students we graduate and the expertise we can provide.”

Off

Traditional

White

Student-built rocket flies into the stratosphere

Jeff Zehnder — Mon, 10 Nov 2025 15:47:41 +0000

Student-built rocket flies into the stratosphere Jeff Zehnder Mon, 11/10/2025 - 08:47

Jeff Zehnder

Go for launch!

The 12-foot-tall rocket roared off the pad, streaming higher and higher until it was barely more than a pinprick in the morning sky.

At 9:15 a.m. on Sunday, October 12, the ��ý�� Sounding Rocket Lab (SRL) successfully launched a rocket to 90,000 ft. in altitude.

Designed and built by students in the club, the Mamba III rocket was a multiyear effort for SRL.

“Over 100 students worked on this project,” said Robert Umali, the team solids/composites lead and an aerospace sophomore. “Our test fire in March performed flawlessly. This rocket is built like a tank.”

Built From Scratch

Although off-the-shelf rocket plans are available online, the team elected to design theirs from the ground up, said Tyler Boim, team co-captain and an aerospace senior.

“Anything that we can make in-house we do. We fully made our avionics, composites, structures, and propellant. You understand each part and why it’s there. We’re not building Legos. You become a better engineer,” Boim said.

Putting the extra work into an independent design has also had career benefits for members like Nick Kieft, fellow team co-captain and an aerospace senior.

“It’s experience for industry. In internship interviews, most of what I talk about with companies is the team. I manufactured this, designed that, tested this,” Kieft said.

The successful launch in California’s Mojave Desert was a moment of exhilaration for all the team members, but only one portion of the day’s excitement, as the rocket body also contained sensors and cameras to track the flight and its landing.

Hitting Mach 3.36

“Mamba had a maximum Mach number of 3.36, equivalent to a velocity of 2,393 mph. Consistent communication of the rocket's flight computers throughout ascent and descent enabled us to determine a landing position and recover the vehicle. The final GPS coordinates were within 50 feet of the landing location,” Kieft said.

Getting to the finish line was not always easy. The team experienced significant setbacks in launches on the previous Mamba I, which suffered a nose cone failure, as well as Mamba II, which exploded midflight.

“Mamba III used the same principles of the original design, but was reworked to account for lessons learned. We spent an entire year recharacterizing the propellant. We overbuilt this rocket to guarantee there would be no failures,” Boim said.

Next Steps

With the successful launch, the team is moving on to a much bigger goal called Spaceshot. They are beginning work on a new rocket design that can reach at least 350,000 ft. in altitude and become only the second student rocketry organization in the world to cross the atmospheric boundary into space – internationally designated at 328,000 ft.

“There will be big infrastructure improvements. We’ll be developing it over the next year or two,” Boim said.

Although that launch will be after senior team members like Boim and Kieft graduate in May 2026, each team stands on the shoulders of earlier graduates, incorporating their design and education in the next iteration.

“I won’t necessarily be here for that launch, but a lot of the work you do leading up to it is just as valuable and rewarding,” Kieft said. “There’s smaller milestones along the way. SRL takes all the important first principles we learn in class to the next level.”

Additional Photos

Onboard still of the rocket near apogee.

Avionics team tracking the rocket during ascent.

The rocket at liftoff.

Recovery of the rocket after landing.

SRL Team Members

Performing final avionics bay integration.

The 12-foot-tall rocket roared off the pad, streaming higher and higher until it was barely more than a pinprick in the morning sky. At 9:15 a.m. on Sunday, October 12, the...

Off

Traditional

White