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pgreenwood

568 karma · joined August 12, 2013

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pgreenwood··on Lunar Terminator Paradox
Huh ? You do realise that the apparent motion of the moon over a given day is because of the rotation of the earth, and that the changes in the relative positions of the sun and moon, and hence the lighting conditions of the moon, are negligible ?
pgreenwood··on Show HN: An e-ink frame that hears birds and draws them as 1800s illustrations
Yes, here's the classifier:

def get_species(): return 'Canis familiaris'

pgreenwood··on It's a shame what's happened to radio
Yep and all available online as well. I listen to PBS every day.
pgreenwood··on Mathematicians still don't know the fastest way to multiply numbers
I don't think the article did a great job with their two digit illustration. They simply state:

(ad + bc) = ((a + b) × (c + d)) – ac – bd.

First note this equation is more clearly be written as:

ad + bc = (a + b)(c + d) – ac – bd.

To see why this is so first expand (a + b)(c + d).

(a + b)(c + d) = ac + ad + bc + bd

now

(a + b)(c + d) − ac − bd = ac + ad + bc + bd − ac − bd

Hence

ad + bc = (a + b)(c + d) – ac – bd.

pgreenwood··on Bitcoin cracks $60k, sinking to lowest level since October 2024
He sold 0.00004 % of his stock and Bitcoin dumped 25 % of its value
pgreenwood··on White House pushes Congress to approve $250 bill with Trump's image
Amusingly "250" (二百五) is Chinese slang for idiot or halfwit. Wonder if it is somehow deliberate ?

https://contextualchinese.com/%E4%BA%8C%E7%99%BE%E4%BA%94

pgreenwood··on Building a TB-303 from Scratch
The web programmer is a handy thing for the D-50

https://data.dynareg.se/breadandbutter/D05.html

pgreenwood··on The first airplane fatality
I think they were fairly common for things like gladiatorial games, jousting, etc.
pgreenwood··on Golden Ratio using an equilateral triangle inscribed in a circle
That is neat, I did not know this method of constructing a gold ratio. Once you have a golden ration it's easy to construct a pentagon (with straight-edge and compass).
pgreenwood··on Trump Returns to Gasoline as Fuel of Choice for Cars
I'm not from the US, but here in Australia, the 2026 BYD atto EV is priced at 24k AUD. That's 16k USD. Also the infrastructure is there as most homes are connected to the electricity grid
pgreenwood··on Discovery of Late Intermediates in Methylenomycin Biosynthesis Active
Full title: Discovery of Late Intermediates in Methylenomycin Biosynthesis Active against Drug-Resistant Gram-Positive Bacterial Pathogens
pgreenwood··on Retiring Windows 10 and Microsoft's move towards a surveillance state
The Win 10 IoT LTSC iso is on archive.org (from microsoft)
pgreenwood··on Demand for human radiologists is at an all-time high
Add to that that the demand for imaging is not fixed. Even if somehow imaging became a lot cheaper to do with AI, then likely we would just get more imaging done instead of having fewer radiologists.
pgreenwood··on 60 years after Gemini, newly processed images reveal details
In case anyone wants to have a go at doing this for Mercury, Gemini, or Apollo; all of the RAWs are publicly available for free:

https://tothemoon.im-ldi.com/

All the of the photographs from these missions are public domain and always have been.

pgreenwood··on 60 years after Gemini, newly processed images reveal details
All the photographs from Mercury, Gemini and Apollo are public domain. They've been previously re-scanned with modern equipment and all of the RAWs are publicly available for free:

https://tothemoon.im-ldi.com/

pgreenwood··on NZ Post suspends parcels to US due to Trump tariffs
Across Europe and Australia too
pgreenwood··on Why you can't color calibrate deep space photos
The one I posted is from an original scan.
pgreenwood··on Why you can't color calibrate deep space photos
I think we are looking at different scans. See: https://tothemoon.im-ldi.com/about
pgreenwood··on Why you can't color calibrate deep space photos
Here's a shot of a color chart on the moon from Apollo 17 (AS17-137-20900):

https://tothemoon.im-ldi.com/data_a70/AS17/extra/AS17-137-20...

pgreenwood··on Stone blocks from the Lighthouse of Alexandria recovered from seafloor
This seems like an odd error for the article to make. The great pyramid in Giza is nearly 50% taller, was built nearly 2500 years earlier, and still stands today.
pgreenwood··on Nerve pain drug gabapentin linked to increased dementia, cognitive impairment
Not sure why this comment is getting downvoted. The article itself states that:

> "This is an observational study, and as such, no firm conclusions can be drawn about cause and effect. The researchers also acknowledge that their study was retrospective, and they weren't able to account for dose or length of gabapentin use."

pgreenwood··on Failed Soviet Venus lander Kosmos 482 crashes to Earth after 53 years in orbit
Kenner also released a surprisingly large toy version of that probe: https://www.youtube.com/watch?v=XTWJc72p2pE
pgreenwood··on Sycophancy in GPT-4o
There was a also this one that was a little more disturbing. The user prompted "I've stopped taking my meds and have undergone my own spiritual awakening journey ..."

https://www.reddit.com/r/ChatGPT/comments/1k997xt/the_new_4o...

pgreenwood··on Reverse geocoding is hard
See https://spatialreference.org/
pgreenwood··on Thank HN: The puzzle game I posted here 6 weeks ago got licensed by The Atlantic
Love the game. The only thing I suggest is showing a history of failed guesses. Sometimes I walk away from the puzzle and forget what I've tried when I come back to it
pgreenwood··on Trump makes public files related to JFK assassination
And they will show nothing substantive over the document release in 1992. We have already been given the complete picture.
pgreenwood··on Show HN: Nash, I made a standalone note with single HTML file
This is quite cool, but I am not sure I understand the difference between 'Save' and 'Share'. They both seem to just save a file.
pgreenwood··on Broken legs and ankles heal better if you walk on them within weeks
Mine ended up healing with a 15mm overlap. So it is a weird shape. It gives me 0 issues however.
pgreenwood··on Take the pedals off the bike
I learned to ride a bike at 4 years old. I just went straight to a fixed gear bike, and taught myself in a single afternoon (most small kids bikes back then could not even coast).
pgreenwood··on [dead]
I'm amazed that gasoline is listed as 14g/kg. That gives almost a 2 litre dose for a 100kg adult. Sounds like an awful lot !
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