Technology, robotics and AI, decoded with sources and dates.https://chevlume.com/https://chevlume.com/explainers/transistor-to-quadrillion-data-centre/https://chevlume.com/explainers/transistor-to-quadrillion-data-centre/How transistor counts grew from one at Bell Labs in 1947 to 2,300 in 1971 and 1.2 quadrillion in an AI data-centre POD, with caveats on NVIDIA's figures.Thu, 05 Nov 2026 21:00:00 GMThttps://chevlume.com/explainers/crispr-what-is-approved-today/https://chevlume.com/explainers/crispr-what-is-approved-today/What CRISPR medicine is approved today and what is not: Casgevy, its 2026 paediatric extension, a first in vivo decision due in March 2027 and one infant.Thu, 05 Nov 2026 20:00:00 GMThttps://chevlume.com/explainers/why-mars-sample-return-ended/https://chevlume.com/explainers/why-mars-sample-return-ended/Why NASA's plan to bring Mars rocks to Earth stalled and ended: the 2023 review, the 2040 redesign, the January 2026 budget and what stays on Mars.Thu, 05 Nov 2026 16:00:00 GMThttps://chevlume.com/explainers/how-a-robot-hand-grasps/https://chevlume.com/explainers/how-a-robot-hand-grasps/How robot hands learn to grasp: demonstrations, simulation and touch sensing, with the numbers from the papers and what Boston Dynamics says about Atlas.Thu, 05 Nov 2026 13:00:00 GMThttps://chevlume.com/explainers/from-bigdog-to-electric-atlas/https://chevlume.com/explainers/from-bigdog-to-electric-atlas/From the 2008 BigDog paper to a production electric Atlas in 2026: what Boston Dynamics and its sources say, the specifications and what is still unknown.Thu, 05 Nov 2026 00:30:00 GMThttps://chevlume.com/explainers/why-rockets-can-land-themselves/https://chevlume.com/explainers/why-rockets-can-land-themselves/A returning rocket must stop at exactly zero altitude with no second try. How SpaceX's own engineer says it works, and the Mars-landing maths behind it.Wed, 04 Nov 2026 23:30:00 GMThttps://chevlume.com/explainers/data-centre-power-and-water-use/https://chevlume.com/explainers/data-centre-power-and-water-use/What US data centres use in electricity and water, why the flat years ended, how cooling trades one for the other and what the data cannot show.Wed, 04 Nov 2026 23:20:00 GMThttps://chevlume.com/explainers/why-cubesats-changed-access-to-space/https://chevlume.com/explainers/why-cubesats-changed-access-to-space/A standard 10 cm unit made small satellites cheap to build and launch. Where the idea came from, how NASA flies them and what still takes months.Wed, 04 Nov 2026 22:10:00 GMThttps://chevlume.com/explainers/what-rlhf-can-and-cannot-do/https://chevlume.com/explainers/what-rlhf-can-and-cannot-do/How reinforcement learning from human feedback works in the InstructGPT paper, what it improved, the alignment tax and what it leaves unsolved.Wed, 04 Nov 2026 22:00:00 GMThttps://chevlume.com/explainers/what-is-retrieval-augmented-generation/https://chevlume.com/explainers/what-is-retrieval-augmented-generation/What RAG is, how the original 2020 system worked, what the paper measured and where retrieval fails, with the figures from the sources.Wed, 04 Nov 2026 21:50:00 GMThttps://chevlume.com/explainers/therac-25-software-safety/https://chevlume.com/explainers/therac-25-software-safety/Six overdoses between 1985 and 1987 from a radiation machine whose safety rested on software. What the Leveson and Turner investigation found.Wed, 04 Nov 2026 19:50:00 GMThttps://chevlume.com/explainers/knight-capital-45-minutes/https://chevlume.com/explainers/knight-capital-45-minutes/A forgotten code path on one of eight servers cost a trading firm $460 million in 45 minutes. What the SEC found about deployment and controls.Wed, 04 Nov 2026 19:45:00 GMThttps://chevlume.com/explainers/the-voyager-golden-record/https://chevlume.com/explainers/the-voyager-golden-record/What is on the disc launched into interstellar space in 1977, how an alien is meant to play it, how long it may last and the arguments around it.Wed, 04 Nov 2026 00:40:00 GMThttps://chevlume.com/explainers/industrial-robots-by-the-numbers/https://chevlume.com/explainers/industrial-robots-by-the-numbers/How many industrial robots exist, where they work, who has the most, and why density tells a different story than totals. IFR figures for 2025.Wed, 04 Nov 2026 00:35:00 GMThttps://chevlume.com/explainers/mars-climate-orbiter-pounds-and-newtons/https://chevlume.com/explainers/mars-climate-orbiter-pounds-and-newtons/One unit mix-up put a Mars orbiter about 170 km too low. What the NASA board found about the people and process failures behind it.Wed, 04 Nov 2026 00:30:00 GMThttps://chevlume.com/explainers/ariane-5-flight-501-37-seconds/https://chevlume.com/explainers/ariane-5-flight-501-37-seconds/How reused software and one unprotected number destroyed a new rocket in 1996, and what the official inquiry recommended.Wed, 04 Nov 2026 00:25:00 GMThttps://chevlume.com/explainers/the-mechanical-turk-chess-automaton/https://chevlume.com/explainers/the-mechanical-turk-chess-automaton/A chess machine from 1770 that was really a hidden person. How the trick worked, who it beat, and how its name ended up at Amazon.Wed, 04 Nov 2026 00:20:00 GMThttps://chevlume.com/explainers/shakey-the-robot-behind-a-star/https://chevlume.com/explainers/shakey-the-robot-behind-a-star/The wobbly 1960s robot that reasoned about rooms and blocks, and left behind the A* and STRIPS algorithms still used in planning.Wed, 04 Nov 2026 00:15:00 GMThttps://chevlume.com/explainers/eliza-deep-blue-and-alphago/https://chevlume.com/explainers/eliza-deep-blue-and-alphago/Three machines that surprised their makers: a 1966 script that only reflected, a chess engine that calculated and a Go player with a famous move 37.Wed, 04 Nov 2026 00:10:00 GMThttps://chevlume.com/explainers/ingenuity-the-mars-helicopter/https://chevlume.com/explainers/ingenuity-the-mars-helicopter/Planned for five flights, it made 72. How a helicopter with a mobile-phone processor flew in air 1% as dense as Earth's, and what ended its mission.Wed, 04 Nov 2026 00:05:00 GMThttps://chevlume.com/explainers/the-apollo-guidance-computer/https://chevlume.com/explainers/the-apollo-guidance-computer/36,864 words of memory woven by hand, and a landing that survived five program alarms because the software knew what to drop.Wed, 04 Nov 2026 00:00:00 GMThttps://chevlume.com/explainers/how-voyager-1-was-repaired/https://chevlume.com/explainers/how-voyager-1-was-repaired/A memory chip died in a 46-year-old computer, 24 billion kilometres away. How engineers found the fault, cut the code into pieces and fixed it.Tue, 03 Nov 2026 23:55:00 GMThttps://chevlume.com/explainers/why-space-computers-are-so-old/https://chevlume.com/explainers/why-space-computers-are-so-old/Radiation flips bits in orbit and wears chips out. Two ways to cope: expensive hardened processors, or fast ones with redundancy and error correction.Tue, 03 Nov 2026 23:50:00 GMThttps://chevlume.com/explainers/slime-mould-and-tokyo-rail-map/https://chevlume.com/explainers/slime-mould-and-tokyo-rail-map/A single cell with no brain grew a network like Tokyo's railways. What the 2010 experiment showed, what press releases added and the algorithm behind it.Tue, 03 Nov 2026 23:45:00 GMThttps://chevlume.com/explainers/belgium-2003-the-4096-extra-votes/https://chevlume.com/explainers/belgium-2003-the-4096-extra-votes/One candidate, 4,096 phantom votes and a bit flip. What the official report concluded, and what later retellings added about cosmic rays.Tue, 03 Nov 2026 23:40:00 GMThttps://chevlume.com/explainers/where-the-word-robot-comes-from/https://chevlume.com/explainers/where-the-word-robot-comes-from/A brother's suggestion, a Czech word for forced labour and a 1920 play about artificial workers who were not made of metal at all.Tue, 03 Nov 2026 23:35:00 GMThttps://chevlume.com/explainers/what-quantum-computers-can-do/https://chevlume.com/explainers/what-quantum-computers-can-do/Qubits, errors, advantage claims and the threat to encryption, with every result labelled as demonstrated, claimed by a company or projected.Tue, 03 Nov 2026 23:30:00 GMThttps://chevlume.com/explainers/open-source-vs-open-weights-ai/https://chevlume.com/explainers/open-source-vs-open-weights-ai/What 'open' really means for AI models: the Open Source AI Definition, open weights, restrictive licences and why the difference changes what you may do.Tue, 03 Nov 2026 23:25:00 GMThttps://chevlume.com/explainers/what-is-an-ai-agent/https://chevlume.com/explainers/what-is-an-ai-agent/An agent is a model that chooses its own steps and uses tools in a loop. How that differs from a workflow, how it is tested and how it fails.Tue, 03 Nov 2026 23:20:00 GMThttps://chevlume.com/explainers/how-language-models-are-trained/https://chevlume.com/explainers/how-language-models-are-trained/From tokens to chat: next-token prediction, human feedback, scaling laws and why models hallucinate, with the numbers from the original papers.Tue, 03 Nov 2026 23:15:00 GMThttps://chevlume.com/explainers/why-space-launch-got-cheaper/https://chevlume.com/explainers/why-space-launch-got-cheaper/Reusable boosters cut the cost per kilogram to orbit about twentyfold. What the numbers really show, what stayed expensive and where Starship stands.Tue, 03 Nov 2026 23:10:00 GMThttps://chevlume.com/explainers/how-humanoid-robots-work/https://chevlume.com/explainers/how-humanoid-robots-work/Motors, sensors, balance and hands: what a humanoid robot is made of, what it does reliably today and why spec sheets flatter the machine.Tue, 03 Nov 2026 23:05:00 GMThttps://chevlume.com/explainers/ai-electricity-use/https://chevlume.com/explainers/ai-electricity-use/Data centres used about 485 TWh in 2025, slightly over 1.5% of global demand. AI is the fast-growing part, and local grids are the bottleneck.Thu, 29 Oct 2026 16:05:44 GMT