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Comment Re:They didn't think of this? (Score 1) 41

You are wrong. Satellites do not transmit the P code directly, but the Y code, which is an encrypted version of the P code. Advanced military receivers can lock on the Y code directly. They don't need the C/A code and you cannot spoof the Y code, thus they are not affected by spoofing. Advanced civilian receivers cannot lock on the Y code, but if they can lock on the C/A code, then they can use it even without decryption. Thus they are affected by spoofing of the C/A code. Regular civilian receivers, like those found in cell phones, cannot make use of the Y code.

Comment The joy of C (Score 1) 24

That is what happens when you use a PDP-11 assembler in 2022. There is no shortage of languages that perform automatic index checking (e.g. Ada, C#, Java, Python, Rust, ...). And yet, billions in damage are incurred every year with those bugs and nothing changes. To quote Hoare:

Many years later we asked our customers whether they wished us to provide an option to switch off these checks in the interest of efficiency on production runs. Unanimously, they urged us not to—they already knew how frequently subscript errors occur on production runs where failure to detect them could be disastrous. I note with fear and horror that even in 1980, language designers and users have not learned this lesson. In any respectable branch of engineering, failure to observe such elementary precautions would have long been against the law.

Comment Re:It's called Ethereum (Score 1) 48

Or rather, Uniswap and co. The ridiculous fees of Ethereum don't make these things very practical yet. What I find annoying in the media coverage (including here) is the sole emphasis on the potential value of coins or tokens as investment. The important thing is the technology and as you pointed out it has considerably improved since bitcoin appeared. It still has a long way to go. What's most interesting is that we don't yet know how to build a really good blockchain-based network, nor do we know which applications (and they go far beyond financial services) will succeed, with many yet to be invented.

Comment Re:It's amazing so much weight was allocated to th (Score 4, Informative) 40

The capsule's centre of gravity is deliberatley off-axis. These are counterweights that put it back on the vertical axis. This is needed from launch all the way to separation of the cruise stage, after which they are jettisoned. Thus the capsule enters at an angle, and generates lift. It is therefore aimed a bit short. If you look at the EDL animation you'll see nitrogen thrusters on the back shell that adjust the orientation of the capsule during entry. If the trajectory is short, the capsule pitches up thus increasing lift. If it is long, it pitches down thus decreasing lift. Cross-range errors can also be corrected to some extent. All this significantly reduces the size of the landing ellipse, and allows the rover to drive to its target in a reasonable amount of time.

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