Rocket geek, orbits nerd, electric car driver, history buff, technical writer. Opinions my own. May commit puns. Also found on LinkedIn and Bluesky.

Joined February 2014
A person born in China at the end of WWII saw China's power rise as its working age population tripled in their lifetime. But now it has plateaued. A person born today will see that growth reverse. China's working age population will drop by 1 million per month for a long time.
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Josh Hopkins retweeted
Regarding Russian conscripts, this is not the case. The overwhelming percentage of Russian forces fighting in this war are men well over 30 who accepted service contracts for money. They were not conscripted, or mobilized. For more on this topic: warontherocks.com/a-return-t…
Replying to @skscartoon
The endless slaughter of Ukrainian and Russians must stop. We should some sympathy for the poor Russian conscripts too. Those kids have no choice but to fight and die in drone strikes.
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Josh Hopkins retweeted
Peter Koch, editor and publisher of the long-running Moon Miner's Manifesto, passed away on October 8. He was 88. Peter advocated for developing and settling the Moon for most of his life. Whether through the NSS or the Moon Society, which he helped create, Peter held the knowledge, lore, and spirit that kept it all going. He will be sadly missed. nss.org/remembering-peter-ko…
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Josh Hopkins retweeted
No one in the history of media knew the interior workings of a young boy’s brain better than Bill Watterson
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NASA sometimes gets some serious flak for being an expensive organization. However, there are major differences between NASA and for example a private firm making aerospace products. NASA being publically funded, is obligated to make (almost) everything they research public domain available, and because everyone thinks "rockets" they dont know that NASA has been a world leading centre for both gear and rolling bearing research for over fifty years. NASA has done cutting edge research into both these topics at NASA Lewis Research Center and the Glenn Research centre. Why do rockets care about gears and bearings ? Well, there are different types of rocket motors, and only solid fuel rockets are essentially devoid of moving parts, many of the rocket engines used are liquid fuel rockets, and that means ... PUMPS, which are full of gears and bearings (the Space Shuttle engines and Saturn V engines finally moved to direct drive, eliminating the gear reduction). The Saturn 1B (pictured) has a 5000 hp, 33,000rpm gearbox in its turbopump which had to be very lightweight. A huge amount of the work done at these centres was overseen by the godfather of gears and bearings. Which is now centred things like rotorcraft applications. Erwin Zaretsky, if you want to know how to design bearings and look at gear tribology, if you read everything Zaretsky has published on them, there is almost nothing you wont know how to do. The bulk of this research is only freely available because NASA is publically funded. So yes, NASA has spent a lot of money over the years, but unlike with most private firms, a large proportion of the intellectual results are fed back into the global human hive engineering mind. Here is a link to one of my favourite reads, the classis "Liquid Rocket Engine Turbopump Gears." which is as good a place as any to start reading about gears in an exciting application. ntrs.nasa.gov/api/citations/… Erwin is not a young man anymore, but is still around and its a jolly good thing he worked for NASA because we get to read all his stuff for free ! My university theis used free NASA papers from these research centres as its primary source for data, although one had some typos in some of the equations, so I wrote to NASA, and they fixed it ! If thats not good value for humanity, what is ?
Psst... Hey you... Have you heard about asymmetric gears? You know, gears where the teeth feature different pressure angles on each side of a tooth? Well, they're pretty awesome. Allows for higher load handling in one direction & stronger, smaller, lighter gears. Also cuts down on noise & vibration, along with offering a better contact ratio. They're used in the gearboxes of various turboprops and other demanding applications with 50% greater power handling than standard tooth profiles. So, if you didn't know, now you know. Just don't drive them too hard the opposite way... ----- Sources: sciencedirect.com/science/ar… ik.imagekit.io/agmamedia/gt/… akgears.com/pdf/Direct%20Gea… pemltd.com/unimegagear/
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Josh Hopkins retweeted
100 years ago today, on October 21, 1926, a British airship dropped two fighters from the sky! The R.33 climbed to 2,000 ft above Pulham airship station in England and released two Gloster Grebe fighters suspended from its keel. One sat ahead of the front engines, the other closer to the rear. It was a radical idea. 1/3
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Josh Hopkins retweeted
Word reached me today that retired NPR host Noah Adams passed away Friday. We were not close, but Noah unintentionally showed me one of life's most important lessons. It said a lot about him so I'd like to share. It was Thanksgiving in our brand new HQ on Mass Avenue. On Thanksgiving my routine was eating in the afternoon with family and then napping before my nightshift. I'd make it to work right at my starting time because the news was slim, what the White House served for dinner and football games. I got there at 9 and went straight to the cafeteria to buy a soda pop before my shift. When I got there I found Noah on his hands and knees scraping the floor with a small, straight edged razor blade we usually used to cut tape. In those days, the All Things Considered staff threw a “family” Thanksgiving dinner. Here it was, hours later, and Noah was still there. Noah’s job, typically, was to roast the turkey not cleaning up. He was scraping smooshed stuffing from the floor. I was shocked. One of the most famous broadcasters in all of public radio was under a table cleaning. “Noah,” I asked, is everything ok?” “Yes,” Noah said, “I promised Murray I would leave the cafeteria the way I found it.” Murray was our building and infrastructure guy. All at once I felt insignificant in the face of Noah’s gesture. I stammered an apology about needing to be in the newsroom and he told me it was ok. I still reflect on that moment. I knew the lessons but came away with an adult’s understanding. Leadership. Integrity. Caring for everyone in your universe no matter their station in life. Humility. The list goes on. Every time I think about that brief encounter I realize something new. Thank you, Noah, for having such an impact on me. Among my treasured memories, you are among the top.
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People seem confused about why Tesla is getting so much backlash over its new "flying Roadster." For those of us who were once genuinely enthusiastic about Tesla, this isn't about hating innovation. It's about a long history of broken promises, misleading expectations, and increasingly absurd marketing. Tesla unveiled the second-generation Roadster in 2017, took customer deposits, and promised deliveries in 2020. Six years past that deadline, it still hasn't delivered the car. Instead, it's demonstrating an even more outrageous version with features that will likely never make it into production. The original 2nd gen Roadster would still be an amazing car today. Why not just deliver what was promised? Then there's Full Self-Driving. Tesla marketed the idea that Model 3 owners could turn their cars into income-generating robotaxis. That never materialized. Even if the technology eventually gets there, the opportunity has already passed for many early buyers. Timing matters. Delivering something a decade late isn't fulfilling the promise you sold to customers. And then there's Solar Roof. Unveiled in 2016 as a revolutionary approach to residential solar, it struggled with costs, installation challenges, and adoption far below expectations. After nearly a decade, Tesla discontinued it entirely in August 2026. Another grand vision abandoned, leaving existing customers with a discontinued product to maintain. Then came the Cybertruck, marketed as a nearly indestructible, revolutionary truck. Instead, we got a vehicle with questionable build quality, numerous recalls, expensive repairs, disappointing results in several real-world off-road tests, and specifications that fell short of the original promises. It literally looks like a dumpster, but aesthetics aside, the collapsing demand speaks volumes about the reality of what Tesla delivered. Another heavily hyped product that fell dramatically short of expectations. This is how consumer trust erodes. Not through one disappointment, but through years of accumulating them. And this is part of the reason why many people who were once enthusiastic about Tesla have become critical and cynical about it. But there's something even more fundamental here: Tesla has completely departed from the grounded, practical vision that made so many of us enthusiastic about the company in the first place. Electric cars were ambitious, but the idea was grounded in reality. People could charge at home, infrastructure could gradually expand, technology could improve, and millions of ordinary people could eventually benefit. There was a realistic path toward mass adoption. What the hell does a flying Roadster powered by compressed-air thrusters have to do with any of that? It's an expensive, impractical engineering stunt with enormous packaging, safety, and regulatory challenges, and no credible near-term path toward mass-market usefulness. Modern electric cars already achieve ridiculous acceleration without this nonsense. What practical problem does it solve? Who actually needs it? When will ordinary consumers benefit? And watching Tesla fans compare this experimental prototype in a Roadster-shaped shell to actual production vehicles people can buy today is ridiculous. What's especially infuriating is the cult-like mentality surrounding all of this. You can't point out the history of failed promises, question the practicality, or demand realistic timelines without being accused of being a "hater" or having "Elon derangement syndrome." Tesla deserves recognition for helping make electric cars a reality, but that success doesn't give it a blank check to keep marketing increasingly fantastical promises while failing to deliver on previous commitments. This isn't hatred. It's disappointment from people who once believed in the company, watched it accomplish extraordinary things, and have since watched it increasingly substitute practical innovation with spectacle and promises. Elon fanboys are also ignoring a bigger pattern that goes beyond Tesla. What made many of us enthusiastic about Elon and Tesla and in the first place was a grounded vision of technological progress that could genuinely improve millions of lives. Electric cars were ambitious, but practical, achievable, and useful to ordinary people. Now we're supposed to get excited about flying cars with compressed-air thrusters that have no credible path to mass adoption and solve no meaningful problem for the average consumer. It's the same kind of thinking behind marketing the colonization of Mars as some urgent necessity for humanity's survival. There's nothing wrong with space exploration, but Earth isn't about to become uninhabitable because of the Sun. We're talking about geological timescales, while humanity faces enormous problems RIGHT NOW: poverty, hunger, access to education, corruption, abuse of power, wars, and a lack of government accountability. We have plenty of very real problems to solve before worrying about humanity's survival on another planet. And then there's DOGE. I was genuinely excited about the original idea of making government more efficient, reducing waste, and increasing accountability. Instead, we got questionable savings figures, inexperienced people making sweeping decisions, serious concerns over access to sensitive personal information, and an initiative that ultimately fizzled out without delivering its grand promises. Another enormous narrative that fell apart when confronted with reality. That's what makes all of this so frustrating. It's not that we stopped believing in technological progress. It's that we've watched someone who once pursued grounded, transformative ideas increasingly embrace fantastical promises, political spectacle, and questionable narratives disconnected from practical reality. And somehow, pointing out this history of disappointment gets you labeled a "hater" or accused of having "Elon derangement syndrome." The problem isn't dreaming big. It's repeatedly selling people those dreams, failing to deliver, and then expecting everyone to applaud the next, even more ridiculous promise without asking what happened to the last one. The world doesn't need more spectacular promises. It needs practical solutions to real problems, honest expectations, and accountability for what was promised. That's what made Tesla exciting in the first place, and that's what so many of us feel has been betrayed.
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Josh Hopkins retweeted
SpaceX option package for new Tesla Roadster will include ~10 small rocket thrusters arranged seamlessly around car. These rocket engines dramatically improve acceleration, top speed, braking & cornering. Maybe they will even allow a Tesla to fly …
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Josh Hopkins retweeted
I stand with the people of Ukraine. Putin clearly has zero respect for the administration and our country. He violated the energy ceasefire yesterday which is a giant middle finger to President Trump. My thoughts are with the people of Ukraine as they continue to be under assault from Russian ballistic missiles.
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Of note for those who believe it is good to be accurate:
Today I channeled my energy into this very unofficial but passionate petition for scientists to start drawing icebergs in their stable orientations. I went to the trouble of painting a stable iceberg with my watercolors, so plz hear me out. (1/4)
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Norman Rockwell, From the Earth to the Moon, 1969.
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Josh Hopkins retweeted
Panelled doors wasn't a pretty extra but a clever solution to doors expanding with moisture and warping or jamming shut. Because wood expands and contracts in relation to the ambient air humidity (and also rain etc. if outdoors), the wood panels (not nailed or glued) could move freely inside the groves of the frame. This allowed tight doors that shut very close to the door frame, often mere millimeters or fractions of an inch, giving us ncreased privacy and better acoustics. And they look very charming.
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Josh Hopkins retweeted
Did you know that the world's second largest landlocked country, Mongolia, has a navy? The 'fleet' consists of a single vessel, the tugboat Sukhbaatar III, which operates on freshwater Lake Khövsgöl. The Mongolian navy has a total of seven personnel.
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Here's a fact to drive home just how incredible the current tanker market is: It is now cheaper to book a standard Falcon 9 launch ($74m) than it is to take a VLCC from the USG to the Far East (~$80m). #OOTT #tankers
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Josh Hopkins retweeted
People make their worst decisions at the moments that matter most, and rules exists to make one decision for them at that moment. Here a list of useful rules to keep in mind:
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Replying to @boston25
I quite literally have the receipts
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Basic data literacy 😆
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Josh Hopkins retweeted
Weird that Ben Affleck uses python. I always saw him as more of a .bat man (if you are under 40 you probably won't understand this anyway so sorry about this)
Ben Affleck do you use uv?
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Back in the 1930s, before ski lifts, you got to the top of the hill using the "up ski". This is the Auburn Ski Club up-ski being used at their hill near Cisco Grove. Just about 100 years later, the old up-ski still sits on the side of the mountain, waiting for skiers who will never arrive, with Interstate 80 far below.
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Russia has a message for foreign diplomats in Kyiv: leave, or risk your lives. Our answer: We are staying. The EU Delegation is staying. Threatening us will not stop Europe’s support for Ukraine. It only reminds us why that support matters! 🇪🇺🤝🇺🇦 @EUDelegationUA
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