科学与数学library.sciencemadness.org编辑精选
《点火：液体火箭推进剂非正式史》（1972）
Ignition: An Informal History of Liquid Rocket Propellants (1972) [pdf]
2015 — 2022，它一次次回到首页
黑点是上首页（≥ 50 分）的那次投稿，空心点是没冲上去的投稿，点越大分数越高。
导读
《Ignition!》是 1972 年出版的液体火箭推进剂非正式发展史，作者以幽默笔调讲述工程师们寻找、试验各种推进剂（包括许多极其危险和失败的方案）的历程。此 PDF 由 sciencemadness.org 扫描上传，因绝版多年而成为 Hacker News 反复推荐的经典。
为什么经久不衰：它把严肃的火箭化学写成妙趣横生的工程冒险，兼具史料价值与可读性，且已重新出版，至今仍是了解推进剂研发史的最佳入门读物。
HN 评论精选
上传者自述：绝版期间他的扫描让这本书得以流传
这是我童年最爱的书之一，也是我扫描上传到 sciencemadness.org 的最后一批书之一。我开始扫描时 Google Books 和 HathiTrust 还不存在，后来世界赶超了我能做的，我就停了。但这么多年来这么多人喜欢我的这个扫描版本，我很自豪。
sciencemadness查看英文原文
This was a favorite book of mine as a child. It was one of the last books that I scanned and uploaded to sciencemadness.org. That's probably for the best, since I was still learning how to make good scans and PDFs with the early books. When I first started scanning and uploading books, Google Books did not yet exist. The HathiTrust did not yet exist. Project Gutenberg and Distributed Proofreaders did exist, but their focus on perfect text transcription of non-technical writing did not really suit the books that I wanted to share. I stopped scanning books because the world largely caught up and surpassed what I could do. Between HathiTrust, Library Genesis, and sci-hub, there has never been a better time for doing deep-dive reading from the comfort of one's own living room. But I'm proud that so many people have enjoyed my scan of this book over the years.
书中关于氟的段落是流传最广的火箭工程幽默
很多最精彩的火箭工程名言都出自这本书。我最喜欢这段：'它当然毒性极强，但那是最小的问题。它与所有已知燃料自燃，快到从未测出过点火延迟。它还与布、木头和试验工程师自燃，更别提石棉、沙子和水——与水反应是爆炸性的。它可以装在某些普通结构金属里，因为表面会形成一层不溶的金属氟化物保护膜。但如果这层膜被熔化或擦掉又来不及再生，操作者就要面对金属-氟大火。对付这种情况，我一直推荐一双好的跑鞋。'
WJW查看英文原文
Ah yes, the book that many of the best rocket engineering quotes come from. I've always been partial to this one: “It is, of course, extremely toxic, but that’s the least of the problem. It is hypergolic with every known fuel, and so rapidly hypergolic that no ignition delay has ever been measured. It is also hypergolic with such things as cloth, wood, and test engineers, not to mention asbestos, sand, and water-with which it reacts explosively. It can be kept in some of the ordinary structural metals-steel, copper, aluminium, etc.-because of the formation of a thin film of insoluble metal fluoride which protects the bulk of the metal, just as the invisible coat of oxide on aluminium keeps it from burning up in the atmosphere. If, however, this coat is melted or scrubbed off, and has no chance to reform, the operator is confronted with the problem of coping with a metal-fluorine fire. For dealing with this situation, I have always recommended a good pair of running shoes.”
推荐配套阅读 Derek Lowe 的危险化学博客
读起来太精彩了，让《坎巴拉太空计划》看起来像基于真实事件的纪录片。另推荐 Derek Lowe 的 'Things I Won't Work With' 系列，同样是 HN 长期喜爱的危险化学话题。
orbital-decay查看英文原文
An amazing read which makes Kerbal Space Program look like a documentary based on real life events. See also: Things I Won’t Work With [0] series by Derek Lowe, another long time HN favorite on dangerous chemistry. [0] https://blogs.sciencemag.org/pipeline/archives/category/things-i-wont-work-with
已重新出版；书中'工程师不读历史'的教训对软件业同样适用
这本书绝版了一段时间，这个 PDF 曾是唯一低于 400 美元能读到它的方式。现在已重新出版，只要 17 美元，内容基本相同。他在书中多次谈到工程师不读文献的灾难——别人几年前已证明不行的配方，几年后又被重新尝试。这让我想到编程界是否也该引以为鉴。
LeifCarrotson查看英文原文
The book was out of print for a while, and this PDF was the only way to,read it for less than $400. But now it's back in print for $17: https://www.amazon.com/dp/0813595835/ Basically the same content, highly worth reading in either format. He addresses the calamity that engineers don't read several times in the book - formulations are attempted a few years after someone proved it didn't work. Makes me wonder if a similar approach wouldn't be advisable in programming...
历次讨论
同类还值得读
如果月球只有 1 像素：一个极其精确的太阳系模型（2014）
If the moon were only 1 pixel: A tediously accurate solar system model (2014)
一个网页版太阳系模型，以“如果月亮只有 1 像素”的真实比例呈现：你必须一路横向滚动，才能体会行星之间空旷到何等程度。
科学与数学上首页 7 次 · 2014–2025joshworth.com编辑精选沉浸式线性代数（2016）
Immersive Linear Algebra (2016)
《Immersive Linear Algebra》是一本完全免费、开放在线的线性代数“超文本教科书”，其最大特色是大量可交互的图形：读者可以直接拖动、操作图中的向量、矩阵和变换…
科学与数学上首页 5 次 · 2015–2024immersivemath.com编辑精选如何将贝果切成两个相连的半环（2009）
How to Slice a Bagel into Two Linked Halves (2009)
数学家 George Hart 的经典教程，演示如何用一刀把贝果切成两个相互扣住的环，并附上切割步骤与数学原理。
科学与数学上首页 5 次 · 2009–2022georgehart.com“犹太问题”：一组用于歧视的数学题
Jewish problems
一篇 arXiv 论文，整理并讨论苏联时期犹太学生在申请大学数学系时被问到的特殊数学难题：这些题往往有简单解法却极难想到，被用作面试中拒绝犹太考生的手段。
科学与数学上首页 5 次 · 2011–2021arxiv.org你的身体并非为长久而造：人类死亡率数据的一课
Your body wasn’t built to last: a lesson from human mortality rates
文章从人类死亡率随年龄变化的统计规律出发，解释身体并非为长久使用而设计：年轻时死亡风险较低，之后随年龄近似指数上升，像复杂系统在不断累积损伤。
科学与数学上首页 5 次 · 2009–2018gravityandlevity.wordpress.com