Merlin engine creator Tom Mueller tours his Impulse Space facility, detailing the 15,000-pound-thrust Deneb engine and Helios vehicle

6:59 AM · Jun 4, 2026

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  @lrocket @GoToImpulse

  

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  amazing shop

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  BREAKING: Inside Impulse Space with Tom Mueller (@lrocket) (SpaceX's 1st Employee) FULL TOUR The famous engineer behind the Merlin engine, now Founder, CEO & CTO of Impulse Space (@GoToImpulse) ICYMI: Merlin still powers Falcon 9 today, the most reliable rocket engine ever flown & the highest thrust-to-weight ever developed. It's the workhorse behind nearly every SpaceX mission: Starlink launches, Dragon crew & cargo flights to the ISS, & booster landings Tom walks us through the factory floor, from the avionics clean room to a live rocket engine firing in the vacuum chamber Impulse is building the in-space mobility layer: the vehicles & engines that move spacecraft after launch, from LEO to GEO, the Moon, infinity & beyond We cover: → Mira: precision maneuvering spacecraft & its saiph thrusters (8 thrusters, ~50 lbs thrust, 5-yr orbit life) → Helios: long haul same-day delivery vehicle (12 tons of LOX/methane, LEO to GEO) → Deneb Engine: 15,000 lbs thrust engine that powers Helios, ox-rich staged combustion, carbon skirt running over 3,000°F → Why 3D printing is "almost a cheat code" for rocket engines → In-house composite tanks, Novaloy, & copper liners machined from 700 lbs down to 25 → 3 spacecraft in orbit + a 1,200-meter rendezvous → Starlink, iterating Merlin & Raptor, & working with @elonmusk → Nuclear propulsion, the Moon, & why compute needs to move to space 𝐓𝐈𝐌𝐄𝐒𝐓𝐀𝐌𝐏𝐒 (00:00) Tom Mueller, Founder, CEO & CTO of Impulse Space (00:49) Inside Impulse Space (02:32) Avionics Bay floor (02:59) Building rockets at home (03:50) Mira and Helios (08:00) Why Tom left SpaceX (09:33) The Deneb Engine walkthrough (11:42) Testing in Mojave (12:23) Favorite part of the Engine (13:30) How it's 3D Printed (14:21) Why 3D Printing changes everything (16:54) Finding Talent for COPVs (17:28) No Modern hardware without software (19:52) The Mill Turn explained (22:42) Payload Deck Design (25:28) Entering the Secret Area (30:48) Thrust, Flow Rate, & 100 Sensors (32:13) Collision avoidance in Orbit (32:57) The Electric Propulsion Chamber (34:28) Nuclear Electric is the future (38:49) Data Centers in Space (40:28) SpaceX & Starlink's Growth (41:10) Working with Elon (42:07) If not CEO, then what? (42:32) Moon matters more than Mars

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  BREAKING: Inside Impulse Space with Tom Mueller (@lrocket) (SpaceX's 1st Employee) FULL TOUR The famous engineer behind the Merlin engine, now Founder, CEO & CTO of Impulse Space (@GoToImpulse) ICYMI: Merlin still powers Falcon 9 today, the most reliable rocket engine ever flown & the highest thrust-to-weight ever developed. It's the workhorse behind nearly every SpaceX mission: Starlink launches, Dragon crew & cargo flights to the ISS, & booster landings Tom walks us through the factory floor, from the avionics clean room to a live rocket engine firing in the vacuum chamber Impulse is building the in-space mobility layer: the vehicles & engines that move spacecraft after launch, from LEO to GEO, the Moon, infinity & beyond We cover: → Mira: precision maneuvering spacecraft & its saiph thrusters (8 thrusters, ~50 lbs thrust, 5-yr orbit life) → Helios: long haul same-day delivery vehicle (12 tons of LOX/methane, LEO to GEO) → Deneb Engine: 15,000 lbs thrust engine that powers Helios, ox-rich staged combustion, carbon skirt running over 3,000°F → Why 3D printing is "almost a cheat code" for rocket engines → In-house composite tanks, Novaloy, & copper liners machined from 700 lbs down to 25 → 3 spacecraft in orbit + a 1,200-meter rendezvous → Starlink, iterating Merlin & Raptor, & working with @elonmusk → Nuclear propulsion, the Moon, & why compute needs to move to space 𝐓𝐈𝐌𝐄𝐒𝐓𝐀𝐌𝐏𝐒 (00:00) Tom Mueller, Founder, CEO & CTO of Impulse Space (00:49) Inside Impulse Space (02:32) Avionics Bay floor (02:59) Building rockets at home (03:50) Mira and Helios (08:00) Why Tom left SpaceX (09:33) The Deneb Engine walkthrough (11:42) Testing in Mojave (12:23) Favorite part of the Engine (13:30) How it's 3D Printed (14:21) Why 3D Printing changes everything (16:54) Finding Talent for COPVs (17:28) No Modern hardware without software (19:52) The Mill Turn explained (22:42) Payload Deck Design (25:28) Entering the Secret Area (30:48) Thrust, Flow Rate, & 100 Sensors (32:13) Collision avoidance in Orbit (32:57) The Electric Propulsion Chamber (34:28) Nuclear Electric is the future (38:49) Data Centers in Space (40:28) SpaceX & Starlink's Growth (41:10) Working with Elon (42:07) If not CEO, then what? (42:32) Moon matters more than Mars

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  @elonmusk 👀

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  BREAKING: Inside Impulse Space with Tom Mueller (@lrocket) (SpaceX's 1st Employee) FULL TOUR The famous engineer behind the Merlin engine, now Founder, CEO & CTO of Impulse Space (@GoToImpulse) ICYMI: Merlin still powers Falcon 9 today, the most reliable rocket engine ever flown & the highest thrust-to-weight ever developed. It's the workhorse behind nearly every SpaceX mission: Starlink launches, Dragon crew & cargo flights to the ISS, & booster landings Tom walks us through the factory floor, from the avionics clean room to a live rocket engine firing in the vacuum chamber Impulse is building the in-space mobility layer: the vehicles & engines that move spacecraft after launch, from LEO to GEO, the Moon, infinity & beyond We cover: → Mira: precision maneuvering spacecraft & its saiph thrusters (8 thrusters, ~50 lbs thrust, 5-yr orbit life) → Helios: long haul same-day delivery vehicle (12 tons of LOX/methane, LEO to GEO) → Deneb Engine: 15,000 lbs thrust engine that powers Helios, ox-rich staged combustion, carbon skirt running over 3,000°F → Why 3D printing is "almost a cheat code" for rocket engines → In-house composite tanks, Novaloy, & copper liners machined from 700 lbs down to 25 → 3 spacecraft in orbit + a 1,200-meter rendezvous → Starlink, iterating Merlin & Raptor, & working with @elonmusk → Nuclear propulsion, the Moon, & why compute needs to move to space 𝐓𝐈𝐌𝐄𝐒𝐓𝐀𝐌𝐏𝐒 (00:00) Tom Mueller, Founder, CEO & CTO of Impulse Space (00:49) Inside Impulse Space (02:32) Avionics Bay floor (02:59) Building rockets at home (03:50) Mira and Helios (08:00) Why Tom left SpaceX (09:33) The Deneb Engine walkthrough (11:42) Testing in Mojave (12:23) Favorite part of the Engine (13:30) How it's 3D Printed (14:21) Why 3D Printing changes everything (16:54) Finding Talent for COPVs (17:28) No Modern hardware without software (19:52) The Mill Turn explained (22:42) Payload Deck Design (25:28) Entering the Secret Area (30:48) Thrust, Flow Rate, & 100 Sensors (32:13) Collision avoidance in Orbit (32:57) The Electric Propulsion Chamber (34:28) Nuclear Electric is the future (38:49) Data Centers in Space (40:28) SpaceX & Starlink's Growth (41:10) Working with Elon (42:07) If not CEO, then what? (42:32) Moon matters more than Mars

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  Tom Mueller (@lrocket) says his "proudest development" as the 1st Employee at SpaceX was creating the Merlin engine: "Currently flying on Falcon 9, it is the most reliable rocket engine ever developed, and also the highest thrust to weight of any rocket engine ever developed."

  

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  "I worked on Starship for the last six years at SpaceX." " When I left, I had the plan of launch mostly being solved or is being solved."

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BREAKING: Inside Impulse Space with Tom Mueller (@lrocket) (SpaceX's 1st Employee) FULL TOUR The famous engineer behind the Merlin engine, now Founder, CEO & CTO of Impulse Space (@GoToImpulse) ICYMI: Merlin still powers Falcon 9 today, the most reliable rocket engine ever flown & the highest thrust-to-weight ever developed. It's the workhorse behind nearly every SpaceX mission: Starlink launches, Dragon crew & cargo flights to the ISS, & booster landings Tom walks us through the factory floor, from the avionics clean room to a live rocket engine firing in the vacuum chamber Impulse is building the in-space mobility layer: the vehicles & engines that move spacecraft after launch, from LEO to GEO, the Moon, infinity & beyond We cover: → Mira: precision maneuvering spacecraft & its saiph thrusters (8 thrusters, ~50 lbs thrust, 5-yr orbit life) → Helios: long haul same-day delivery vehicle (12 tons of LOX/methane, LEO to GEO) → Deneb Engine: 15,000 lbs thrust engine that powers Helios, ox-rich staged combustion, carbon skirt running over 3,000°F → Why 3D printing is "almost a cheat code" for rocket engines → In-house composite tanks, Novaloy, & copper liners machined from 700 lbs down to 25 → 3 spacecraft in orbit + a 1,200-meter rendezvous → Starlink, iterating Merlin & Raptor, & working with @elonmusk → Nuclear propulsion, the Moon, & why compute needs to move to space 𝐓𝐈𝐌𝐄𝐒𝐓𝐀𝐌𝐏𝐒 (00:00) Tom Mueller, Founder, CEO & CTO of Impulse Space (00:49) Inside Impulse Space (02:32) Avionics Bay floor (02:59) Building rockets at home (03:50) Mira and Helios (08:00) Why Tom left SpaceX (09:33) The Deneb Engine walkthrough (11:42) Testing in Mojave (12:23) Favorite part of the Engine (13:30) How it's 3D Printed (14:21) Why 3D Printing changes everything (16:54) Finding Talent for COPVs (17:28) No Modern hardware without software (19:52) The Mill Turn explained (22:42) Payload Deck Design (25:28) Entering the Secret Area (30:48) Thrust, Flow Rate, & 100 Sensors (32:13) Collision avoidance in Orbit (32:57) The Electric Propulsion Chamber (34:28) Nuclear Electric is the future (38:49) Data Centers in Space (40:28) SpaceX & Starlink's Growth (41:10) Working with Elon (42:07) If not CEO, then what? (42:32) Moon matters more than Mars