The Case for Continuity, with Pam Melroy (Former Deputy Administrator of NASA)

Continuous human presence in orbit has been a cornerstone of U.S. leadership in space for 25 years. But recent changes to NASA’s Commercial LEO Destinations (CLD) strategy have Pam Melroy—former NASA Deputy Administrator and shuttle commander—sounding the alarm. She warns that shifting to short-duration missions risks ceding leadership in LEO and undermining U.S. readiness for Mars, opening the door for China to take the mantle.On this episode of Valley of Depth, we’re joined by Pam to talk about the state of NASA, the future of space stations, and why requirements, the often overlooked backbone of program management, will determine whether the U.S. stays ahead. We trace her career from test pilot to shuttle commander to senior leadership at NASA, DARPA, and the FAA, and unpack what it means to build an architecture that actually holds together from LEO to Mars.We also discuss:Why continuous presence in LEO is a national security and leadership issueHow the CLD Phase 2 shift could reshape investor and partner confidenceThe role of SpaceX and Starship in the Moon–Mars roadmapWhat it takes to write requirements that don’t doom a program from the startPam’s vision of LEO, the Moon, and Mars in 2045…and much more.This episode is brought to you by World Space Business Week, taking place September 15–19 in Paris. WSBW is one of the leading annual gatherings for the global space industry, bringing together executives, investors, government officials, and innovators from across commercial, defense, and satellite sectors. Learn more at wsbw.com.• Chapters •00:00 – Intro00:55 – WSBW Ad01:21 – The key to Pam's success03:32 – The state of NASA05:01 – NASA in the next decade if we stay in our current trajectory06:58 – Why is maintaining a human presence in LEO so important?10:18 – The changing CLD Strategy15:29 – Cost and impact of continuous vs 30-day missions18:01 – NASA's requirements23:50 – Disintegration of requirements27:32 – Impact of the shift in CLD strategy29:52 – Why go back to the Moon?31:35 – Does the media understand the impact of landing on the Moon and Mars?35:19 – Why do 30-day missions make sense37:53 – Will China beat us back to the Moon?41:41 – Cultural impact if China beats us to the Moon45:17 – Does the Artemis program have the right architecture to succeed?47:46 – Is NASA too dependent on SpaceX?52:47 – How much should the U.S. be interested56:02 – What did leading the space shuttle teach Pam about leadership?57:54 – Inspiring the next generation of space exploration58:46 – Prediction 20 years later01:01:37 – Aliens? • Show notes •Mo's socials — https://twitter.com/itsmoislamPayload’s socials — https://twitter.com/payloadspace / https://www.linkedin.com/company/payloadspaceIgnition’s socials — https://twitter.com/ignitionnuclear / https://www.linkedin.com/company/ignition-nuclear/Tectonic’s socials  — https://twitter.com/tectonicdefense / https://www.linkedin.com/company/tectonicdefense/Valley of Depth archive — Listen: https://pod.payloadspace.com/ • About us •Valley of Depth is a podcast about the technologies that matter — and the people building them. Brought to you by Arkaea Media, the team behind Payload (space), Ignition (nuclear energy), and Tectonic (defense tech), this show goes beyond headlines and hype. We talk to founders, investors, government officials, and military leaders shaping the future of national security and deep tech. From breakthrough science to strategic policy, we dive into the high-stakes decisions behind the world’s hardest technologies.Payload: www.payloadspace.comIgnition: www.ignition-news.comTectonic: www.tectonicdefense.com

Logistics rarely makes headlines, but it wins or loses wars. Rune Technologies is betting that the future of contested sustainment won’t be built on warehouses and spreadsheets, but on software. The company recently raised a $24M Series A to accelerate that vision.On this episode of Valley of Depth, we’re joined by Rune co-founder and CEO David Tuttle to talk about how the company is reimagining military logistics from the ground up. We trace Rune’s path from early prototypes to today’s TyrOS platform, discuss the cultural inertia inside the Pentagon, and unpack what it means to build software that commanders can trust under fire.We also get into:The founding story of Rune and the early technical unlocksBuilding TyrOS and winning adoption with frontline commandsWhat it takes to design software soldiers actually want to useWhy logistics is becoming a strategic lever in great power competitionThe long-term vision for software-defined sustainment…and much more.This episode is brought to you by World Space Business Week, taking place September 15–19 in Paris. WSBW is one of the leading annual gatherings for the global space industry, bringing together executives, investors, government officials, and innovators from across commercial, defense, and satellite sectors. Learn more at wsbw.com.• Chapters •00:00 – Intro01:02 – WSBW01:27 – The story behind the name "Rune"03:02 – What is Rune building?04:34 – David's background and how he ended up founding Rune08:10 – Why David and Peter Goldsborough had to make Rune exist10:43 – Logistics in warfare13:02 – How logistics are still being tracked today and why it’s outdated17:05 – How TyrOS changes the logistics of the battlefield21:56 – Operating in denied or degraded environments24:54 – Who's using Rune's products right now and future scaling29:20 – What has surprised David the most31:08 – Pilot to program of record with the DoD33:39 – Competitive landscape36:01 – Will Rune stay in Defense?37:30 – Will software like Rune's change military doctrine?40:28 – Software making decisions in life-or-death scenarios42:45 – Contrarian beliefs about defense tech46:12 – Milestones to look out for at Rune47:32 – What does the US military look like if Rune succeeds?48:59 – What does David do for fun? • Show notes •Rune’s website — https://www.runetech.co/Mo's socials — https://twitter.com/itsmoislamPayload’s socials — https://twitter.com/payloadspace / https://www.linkedin.com/company/payloadspaceIgnition’s socials — https://twitter.com/ignitionnuclear / https://www.linkedin.com/company/ignition-nuclear/Tectonic’s socials  — https://twitter.com/tectonicdefense / https://www.linkedin.com/company/tectonicdefense/Valley of Depth archive — Listen: https://pod.payloadspace.com/ • About us •Valley of Depth is a podcast about the technologies that matter — and the people building them. Brought to you by Arkaea Media, the team behind Payload (space), Ignition (nuclear energy), and Tectonic (defense tech), this show goes beyond headlines and hype. We talk to founders, investors, government officials, and military leaders shaping the future of national security and deep tech. From breakthrough science to strategic policy, we dive into the high-stakes decisions behind the world’s hardest technologies.Payload: www.payloadspace.comIgnition: www.ignition-news.comTectonic: www.tectonicdefense.com

Tommy Hendrix is Managing Partner at Decisive Point, a venture firm backing early-stage companies developing critical national security technologies. In this episode of Valley of Depth, we unpack what it really means to fund the future of national defense and how venture capital is becoming a tool of statecraft.A former Green Beret turned investor, Tommy brings rare insight into the geopolitical stakes, bureaucratic hurdles, and human motivations behind the new national security startup wave. From combat deployments in Iraq to due diligence in D.C., he’s seen the full arc of how technology shapes power.We get into Decisive Point’s playbook, from why it was built, to how it supports founders navigating the defense industrial complex. Tommy also shares lessons from working inside the machine, the firm’s approach to incubation, and how they decide when a startup can actually shift the deterrence equation.We also dive into:The strategic case for funding earlyWhy some military problems aren’t venture-scaleWhat it takes to build “weapons-grade” startupsThe ethics of AI-enabled kill chainsPrivate capital’s role in a new Cold WarHow the next great defense companies will be bornThis episode is brought to you by World Space Business Week, taking place September 15–19 in Paris. WSBW is one of the leading annual gatherings for the global space industry, bringing together executives, investors, government officials, and innovators from across commercial, defense, and satellite sectors. Learn more at wsbw.com.• Chapters •00:00 - Intro01:14 – From Green Beret into venture04:02 – Deployments that have shaped Tommy's venture career10:54 – What is broken in the US's current procurement process for defense tech?14:51 – A future without humans in the kill chain18:42 – What has changed with defense tech investors?24:05 – How does Tommy pick the right companies to invest in?28:57 – Tommy's work in nuclear32:19 – How helping a portfolio company go through bankruptcy gave Decisive Point a new lens for investment strategies34:49 – How does the firm make decisions37:37 – Companies that were good for the nation but difficult to justify long-term venture39:54 – Must-haves for the US to win the tech race42:55 – Tech gaps that need more focus47:00 – Qualities of a founder Tom is looking for49:22 – What Tom carried over from his military career into his investing career52:01 – The driving force behind Decisive Point • Show notes •Decisive Point’s website — https://www.decisivepoint.com/Decisive Point’s socials — https://x.com/decisivepointvcTommy’s socials — https://x.com/thomasehendrixMo's socials — https://twitter.com/itsmoislamPayload’s socials — https://twitter.com/payloadspace / https://www.linkedin.com/company/payloadspaceIgnition’s socials — https://twitter.com/ignitionnuclear /  https://www.linkedin.com/company/ignition-nuclear/Tectonic’s socials  — https://twitter.com/tectonicdefense / https://www.linkedin.com/company/tectonicdefense/Valley of Depth archive — Listen: https://pod.payloadspace.com/ • About us •Valley of Depth is a podcast about the technologies that matter — and the people building them. Brought to you by Arkaea Media, the team behind Payload (space), Ignition (nuclear energy), and Tectonic (defense tech), this show goes beyond headlines and hype. We talk to founders, investors, government officials, and military leaders shaping the future of national security and deep tech. From breakthrough science to strategic policy, we dive into the high-stakes decisions behind the world’s hardest technologies.Payload: www.payloadspace.comIgnition: www.ignition-news.comTectonic: www.tectonicdefense.com 

In this episode of Valley of Depth, we sit down with Regent cofounder and CEO Billy Thalheimer to explore a radical reimagining of coastal mobility, not with eVTOLs or hyperloops, but with high-speed electric seagliders that skim just above the water.Part hydrofoil, part aircraft, and fully electric, Regent’s vehicles operate in the sweet spot between aviation and maritime. They’re fast enough to replace short-haul flights, regulated like boats, and increasingly viewed by the Pentagon as a new class of strategic asset.Billy walks us through Regent’s founding story, from MIT aerodynamics to launching the world’s largest electric aircraft-by-another-name. We dive deep into the company’s dual-use strategy, its multibillion-dollar commercial backlog, and its early defense work with the U.S. Marine Corps.We also get into:The technical magic behind “float, foil, fly”Why flying 10 feet above water solves big infrastructure problemsRegent’s bet on maritime-first regulationHow seagliders fit into Indo-Pacific logistics and contested environmentsThe case for a new coastal transportation layer and why no one’s built it until now• Chapters •00:00 – Intro01:01 – Why Rhode Island?03:15 – Startup community in Rhode Island07:17 – Founding and origin behind Regent12:10 – How things have changed since the ekranoplan19:05 – How Regent's planes handle a rogue wave20:52 – State of Regent's product build24:35 – Who will be Regent's first operators?26:11 – Regent's regulatory process as a maritime vessel31:59 – What happens when the FAA decides to be involved?36:02 – Commercial vs government use38:15 – When did Regent start talking with the DoD?43:34 – Scaling for dual use commercial vs military46:34 – Raising $90m and common skeptical questions49:39 – What does success for Regent look like?• Show notes •Regent’s website — https://www.regentcraft.com/Regent’s socials — https://x.com/regentcraftMo's socials — https://twitter.com/itsmoislamPayload’s socials — https://twitter.com/payloadspace / https://www.linkedin.com/company/payloadspaceIgnition’s socials — https://twitter.com/ignitionnuclear / https://www.linkedin.com/company/ignition-nuclear/Tectonic’s socials — https://twitter.com/tectonicdefense / https://www.linkedin.com/company/tectonicdefense/Valley of Depth archive — Listen: https://pod.payloadspace.com/• About us •Valley of Depth is a podcast about the technologies that matter — and the people building them. Brought to you by Arkaea Media, the team behind Payload (space), Ignition (nuclear energy), and Tectonic (defense tech), this show goes beyond headlines and hype. We talk to founders, investors, government officials, and military leaders shaping the future of national security and deep tech. From breakthrough science to strategic policy, we dive into the high-stakes decisions behind the world’s hardest technologies.Payload: www.payloadspace.comIgnition: www.ignition-news.comTectonic: www.tectonicdefense.com

In this episode of Valley of Depth, we sit down with Xcimer Energy’s cofounders, Conner Galloway and Alexander Valys, to unpack one of the boldest bets in fusion: resurrecting a Cold War-era laser technology to build the fastest, most scalable path to commercial fusion power.Xcimer has raised over $100 million to bring its inertial confinement fusion system to life, starting with LPK, a high-powered prototype laser built in just four months, and progressing toward Vulcan, a full-scale, ignition-class reactor designed for the grid. We also discuss:Why excimer lasers are making a comebackWhat Xcimer learned from building LPK in just four monthsThe Phoenix-to-Vulcan roadmap for commercial fusionLessons from NIF’s ignition milestone and its limitsThe case for fusion as infrastructure, not just scienceHow Xcimer is positioning itself in a crowded fusion landscape…and much, more. • Chapters •00:00 – Intro01:24 – Payload Pro02:06 – Recent changes in fusion03:29 – Commercial fusion and perceptions on the tech05:18 – Founding story of Xcimer06:51 – Common approaches to fusion today08:48 – Was the National Ignition Facility (NIF) the catalyst to start Xcimer?12:22 – Convincing investors to invest $100m into Xcimer13:34 – What is NIF's goal right now and can it produce electricity?18:04 – Why hasn't the private sector solved the fusion problem?20:25 – Xcimer progress report23:07 – Xcimer's roadmap for the next bigger machine24:41 – Coming up with Athena25:33 – Addressing neutron damage29:54 – The biggest unknown for Xcimer32:29 – Who are Xcimer's first customers35:03 – Cost per megawatt per hour to be competitive37:23 – How much of Xcimer's supply chain is being verticalized38:48 – Vaporizing a missile with a laser41:27 – Other fusion companies Alex and Connor admire44:28 – What inspires a founder or engineer to pursue less proven fusion methods?47:28 – What drives Alex and Connor to keep on going?49:02 – First commercial Xcimer fusion plant • Show notes •Xcimer’s website — https://xcimer.energy/Mo's socials — https://twitter.com/itsmoislamPayload’s socials — https://twitter.com/payloadspace / https://www.linkedin.com/company/payloadspaceIgnition’s socials — https://twitter.com/ignitionnuclear /  https://www.linkedin.com/company/ignition-nuclear/Tectonic’s socials  — https://twitter.com/tectonicdefense / https://www.linkedin.com/company/tectonicdefense/Valley of Depth archive — Listen: https://pod.payloadspace.com/ • About us •Valley of Depth is a podcast about the technologies that matter — and the people building them. Brought to you by Arkaea Media, the team behind Payload (space), Ignition (nuclear energy), and Tectonic (defense tech), this show goes beyond headlines and hype. We talk to founders, investors, government officials, and military leaders shaping the future of national security and deep tech. From breakthrough science to strategic policy, we dive into the high-stakes decisions behind the world’s hardest technologies.Payload: www.payloadspace.comIgnition: www.ignition-news.comTectonic: www.tectonicdefense.com 

Mikkel Vestergaard isn’t a typical aerospace founder. Before building solar-powered stratospheric airships, he spent two decades in humanitarian innovation, distributing a billion malaria nets, co-creating the LifeStraw, and helping eradicate Guinea worm disease. Now, as CEO of Sceye, he’s applying that same ethos to aerospace.In this conversation, Mikkel dives deep into the origins, design, and future of High-Altitude Platform Systems (HAPS). We explore why the stratosphere is emerging as a new layer of infrastructure, filling the gap between satellites and towers, and how Sceye’s helium-filled, solar-powered airships could reshape internet connectivity, earth observation, and national security.We cover:Why Mikkel pivoted from global health to aerospaceThe engineering that makes persistent stratospheric flight possibleHow Sceye closes the “power loop” to stay aloft for monthsCommercial applications from telecom to methane detectionStrategic partnerships with SoftBank, América Móvil, and MawaridThe defense potential of HAPSThe business model behind “infrastructure as a service”What it takes to build investor conviction around a platform that feels left-field• Chapters •00:00 – Intro01:52 – Life before Sceye02:51 – Work at Lifestraw06:31 – What is Lifestraw?07:50 – Making the pivot from global health to aerospace and working at Sceye10:52 – HAPS or High-Altitude Platform Systems12:25 – Why choose a balloon over a fixed wing aircraft?14:04 – Types of payloads16:06 – Not Hindenburg 2.016:48 – How Mikkel's earlier material science experience shaped Sceye's design decisions18:09 – Pitching Sceye to investors19:16 – Common misconceptions of stratospheric platforms20:41 – What can HAPS do for the telecommunications industry?25:03 – How many HAPS would we need to provide global coverage?25:24 – Sceye's equity investor partners26:00 – When Sceye will be fully commercialized28:34 – Other use cases31:33 – Advantages over satellites32:34 – National security use cases33:31 – The business model of HAPS34:52 – Sceye's next iteration of customers35:40 – How Sceye is building their team36:56 – Manufacturing process and scaling37:53 – Capital to scale38:25 – What keeps Mikkel up at night39:38 – What does success to Sceye look like • Show notes •SCEYE’s website — https://sceye.com/Mo's socials — https://twitter.com/itsmoislamPayload’s socials — https://twitter.com/payloadspace / https://www.linkedin.com/company/payloadspaceIgnition’s socials — https://twitter.com/ignitionnuclear / https://www.linkedin.com/company/ignition-nuclear/Tectonic’s socials — https://twitter.com/tectonicdefense / https://www.linkedin.com/company/tectonicdefense/Valley of Depth archive — Listen: https://pod.payloadspace.com/ • About us •Valley of Depth is a podcast about the technologies that matter — and the people building them. Brought to you by Arkaea Media, the team behind Payload (space), Ignition (nuclear energy), and Tectonic (defense tech), this show goes beyond headlines and hype. We talk to founders, investors, government officials, and military leaders shaping the future of national security and deep tech. From breakthrough science to strategic policy, we dive into the high-stakes decisions behind the world’s hardest technologies.Payload: www.payloadspace.comIgnition: www.ignition-news.comTectonic: www.tectonicdefense.com

Julien Barber is an investor at Emerson Collective, a venture and policy firm founded by Laurene Powell Jobs, where he backs bold bets on decarbonization, infrastructure, and long-horizon climate technologies. Before becoming an investor, Julien researched fusion energy at MIT and co-founded a carbon-tech startup. In today’s episode, we go deep into Julien’s investing philosophy, Emerson’s unique model, and the hard tech categories he believes are most undercapitalized.We cover:Why Emerson is structured for risk others can’t takeFusion, fission, and the evolving energy stackAI’s impact on power demand and hardware accelerationHow to invest when the grid is the bottleneckBuilding conviction in hard tech when capital is scarcePublic vs. private roles in scaling fusionWhat a 7-million-fold increase in energy density may actually look like• Chapters •00:00 – Intro01:49 – From scientist to investor04:37 – Why Julien chose fusion08:57 – Investment process at Emerson10:08 – The team at Emerson12:15 – Is Emerson consensus-driven and why is it an LLC?14:07 – Under-invested areas in climate & industrial tech17:24 – Are AI valuations reasonable today?18:59 – Bottlenecks in the grid23:11 – AI energy consumption: hype or real concern?27:10 – Bridging the energy gap29:20 – Fusion’s role in the next decade31:24 – Google & Commonwealth Fusion: serious commercial signal?32:37 – Are we underinvesting in fusion?39:12 – Who will reach commercial fusion first?41:36 – 30-year future if fusion succeeds • Show notes •Emerson’s socials — https://x.com/emcollectiveEmerson’s website — https://www.emersoncollective.com/Mo's socials — https://twitter.com/itsmoislamPayload’s socials — https://twitter.com/payloadspace / https://www.linkedin.com/company/payloadspaceIgnition’s socials — https://twitter.com/ignitionnuclear / https://www.linkedin.com/company/ignition-nuclear/Tectonic’s socials  — https://twitter.com/tectonicdefense / https://www.linkedin.com/company/tectonicdefense/Valley of Depth archive — Listen: https://pod.payloadspace.com/ • About us •Valley of Depth is a podcast about the technologies that matter — and the people building them. Brought to you by Arkaea Media, the team behind Payload (space), Ignition (nuclear energy), and Tectonic (defense tech), this show goes beyond headlines and hype. We talk to founders, investors, government officials, and military leaders shaping the future of national security and deep tech. From breakthrough science to strategic policy, we dive into the high-stakes decisions behind the world’s hardest technologies.Payload: www.payloadspace.comIgnition: www.ignition-news.comTectonic: www.tectonicdefense.com

Welcome to a special Tuesday-edition of Valley of Depth, powered by Integrate.John Conafay spent years inside the space and defense worlds, from Spire to Astranis to the U.S. Air Force, and saw the same problem everywhere: complex programs were managed with spreadsheets, slide decks, and…crossed fingers. So in 2022, he founded Integrate to fix it. What started as a scrappy startup with five engineers has since landed what he describes as one of the largest software contracts in Space Force history. We discuss: Why defense programs are still run on outdated, fragmented toolsWhat Integrate actually does and how it’s different from Smartsheet or Microsoft ProjectHow Conafay won a $25M Space Force contractThe architecture choices behind real-time collaboration in classified environmentsWhy internal tools and status quo software can’t scale with complexityAnd much, much more… • Chapters •00:00 – Intro01:57 – John's background02:59 – What is Integrate?04:02 – Pain points in complex project management06:08 – John's interest in aerospace10:01 – Core product at Integrate11:20 – Why tools weren't implemented before12:50 – DoD project management & efficiency loss14:29 – Multiplayer coordination approach16:19 – Hardest integration problem17:40 – Security architecture20:17 – Go-to-market & government entry22:18 – $25M Space Force contract26:14 – Future Space Force goals27:59 – Government vs commercial customers29:16 – Pricing30:13 – Profitability, team, funding, scaling32:23 – Ideal investor33:20 – Competitors34:50 – Competing with internal tools36:01 – 10-year product vision37:36 – Strategic risks in the next decade39:42 – Hardest part of building Integrate41:34 – Misconceptions about working with the DoD42:55 – Advice for founders & younger self43:53 – John in another life • Show notes •John’s socials — https://x.com/jconafayIntegrate’s socials —https://x.com/Integrate_coIntegrate’s website — https://integrate.co/Mo's socials — https://twitter.com/itsmoislamPayload’s socials — https://twitter.com/payloadspace / https://www.linkedin.com/company/payloadspaceIgnition’s socials — https://twitter.com/ignitionnuclear /  https://www.linkedin.com/company/ignition-nuclear/Tectonic’s socials  — https://twitter.com/tectonicdefense / https://www.linkedin.com/company/tectonicdefense/Valley of Depth archive — Listen: https://pod.payloadspace.com/  • About us •Valley of Depth is a podcast about the technologies that matter — and the people building them. Brought to you by Arkaea Media, the team behind Payload (space), Ignition (nuclear energy), and Tectonic (defense tech), this show goes beyond headlines and hype. We talk to founders, investors, government officials, and military leaders shaping the future of national security and deep tech. From breakthrough science to strategic policy, we dive into the high-stakes decisions behind the world’s hardest technologies. Payload: www.payloadspace.comIgnition: www.ignition-news.comTectonic: www.tectonicdefense.com

Chris Kemp took Astra public in 2021 with a bold vision: low-cost rockets launching daily, bringing sovereign space access to every country on Earth. At its peak, the company was worth over $2 billion. Within two years, that valuation collapsed by 99%. In this episode of Valley of Depth, we go inside one of the most dramatic flameouts and attempted comebacks in the commercial space era. We discuss:Why Astra’s SPAC-era promises didn’t survive contact with realityWhat really went wrong with Rocket 3 and how much of that falls on KempThe decision to take the company private and buy it back for pennies on the dollarHow Astra raised $80M, and its attempt to raise another $100M+The quiet success of its satellite propulsion businessRocket 4, and whether this time is actually differentHow Kemp is repositioning Astra as a mobile, defense-aligned launch platform • Chapters •00:00 – Intro01:53 – What's happened since 2022?02:58 – What kept Astra going after test flight failures?06:46 – Did Astra's engineering approach work against them?08:15 – What Chris believes he got wrong12:51 – Has Chris questioned his leadership at Astra?14:37 – What would Chris have done differently?16:34 – Taking Astra private & investor reactions20:58 – What Chris saw more than anyone else22:20 – Team and factory space at Astra23:20 – Chris's philosophy on rocket building25:54 – Rocket 4 vs Rocket 330:35 – Astra’s renewed business model34:11 – Why is Rocket Lab valued at $16B?36:21 – Engine business & customer trust39:25 – NASA & Astra39:49 – Post-privatization investment45:18 – The team at Astra47:08 – What went wrong with Astra's infamous flight47:54 – Chris's evolving leadership style50:05 – Chris's hardest moment at Astra50:49 – Unfair criticisms of Chris51:54 – What present Chris would tell past Chris53:12 – What keeps Chris going54:57 – Would Astra go public again?57:51 – Astra milestones to watch • Show notes •Chris’ socials — https://x.com/KempAstra’s socials —https://x.com/astraAstra’s website — https://astra.com/Mo's socials — https://twitter.com/itsmoislamPayload’s socials — https://twitter.com/payloadspace / https://www.linkedin.com/company/payloadspaceIgnition’s socials — https://twitter.com/ignitionnuclear /  https://www.linkedin.com/company/ignition-nuclear/Tectonic’s socials — https://twitter.com/tectonicdefense / https://www.linkedin.com/company/tectonicdefense/Valley of Depth archive — Listen: https://pod.payloadspace.com/ • About us •Valley of Depth is a podcast about the technologies that matter — and the people building them. Brought to you by Arkaea Media, the team behind Payload (space), Ignition (nuclear energy), and Tectonic (defense tech), this show goes beyond headlines and hype. We talk to founders, investors, government officials, and military leaders shaping the future of national security and deep tech. From breakthrough science to strategic policy, we dive into the high-stakes decisions behind the world’s hardest technologies.Payload: www.payloadspace.comIgnition: www.ignition-news.comTectonic: www.tectonicdefense.com

Jeff Thornburg helped build Raptor at SpaceX. Now he’s building something new: a spacecraft designed for rapid maneuverability across orbits powered by solar thermal propulsion.In this episode of Valley of Depth, we get into the technical, strategic, and commercial implications of in-space mobility and why it matters now. Topics include:The hardest parts of building a rocket engine (and why most startups get it wrong)The origins of the Raptor engine and lessons from SpaceXWhy Portal is betting on solar thermal propulsionHow Supernova enables fast, responsive movement across LEO, MEO, and GEOThe case for refueling in orbit and designing without dependenciesWhy defense needs faster spacecraft and what commercial use cases followHow Thornburg sees Starship changing the economics of spaceand much more… • Chapters •00:00 – Intro01:44 – What drew Jeff to creating engines?05:13 – Why is building rocket engines still so difficult?11:50 – Jeff's time at SpaceX17:52 – Stratolaunch and Commonwealth Fusion and why Jeff moved on22:50 – Origin of Portal25:25 – Commercial use case27:00 – 5 year vision for Portal's architecture32:01 – Pricing34:52 – Solar thermal propulsion38:14 – What comes after Portal's Supernova?41:15 – Customer traction and Supernova flight45:44 – Competition in solar thermal propulsion49:20 – Fundraising prior to the first launch51:18 – Portal in the next 10 years54:53 – State of Starship • Show notes •Jeff’s socials — https://x.com/JeffThornburgAntares’ socials — https://x.com/PortalSpaceSysAntares’ website — https://www.portalsystems.space/Mo's socials — https://twitter.com/itsmoislamPayload’s socials — https://twitter.com/payloadspace / https://www.linkedin.com/company/payloadspaceIgnition’s socials — https://twitter.com/ignitionnuclear /  https://www.linkedin.com/company/ignition-nuclear/Tectonic’s socials  — https://twitter.com/tectonicdefense / https://www.linkedin.com/company/tectonicdefense/Valley of Depth archive — Listen: https://pod.payloadspace.com/ • About us •Valley of Depth is a podcast about the technologies that matter — and the people building them. Brought to you by Arkaea Media, the team behind Payload (space), Ignition (nuclear energy), and Tectonic (defense tech), this show goes beyond headlines and hype. We talk to founders, investors, government officials, and military leaders shaping the future of national security and deep tech. From breakthrough science to strategic policy, we dive into the high-stakes decisions behind the world’s hardest technologies.Payload: www.payloadspace.comIgnition: www.ignition-news.comTectonic: www.tectonicdefense.com