Only a dabbler in Love2d here but I’d expect that update to be a bit down the line. If I’m not mistaken the current Love2d version 11.5 is (mostly) tied to Lua 5.1 because of LuaJIT, though I understand some later Lua features are backported. And the changelog for the in-dev 12.0 release talks about compiling Love2d for Lua 5.4 as if it’s an optional thing.
I don’t really follow LuaJIT too closely so I’m not sure if they’re even targeting Lua 5.4 let alone 5.5. I remember reading some GitHub issue that suggested some of the design decisions in Lua 5.4 wouldn’t really support LuaJIT goals re: performance.
With that said I’ve been enjoying Love2d even with Lua 5.1 features — as a hobbyist it works just fine for me.
Would certainly appreciate any corrections by those more in-the-know though!
This is a particularly bizarre part of the article to me. Certainly Eric Berger, the article's author who's written more than one book on space at this point knows this.
The President appoints NASA's administrator (subject to Senate approval, of course) and Congress controls NASA's budget. How anyone is puzzled by NASA's focus is beyond me. If I'm being pessimistic, I would assume such people are woefully ignorant of how NASA (and maybe the government as a whole) works. I try to be pessimistic instead of cynical because if I were cynical then I would assume a bunch of negative ulterior motives.
Here is a link [0] to the NASA Authorization Act of 2005. And here's a relevant snippet:
"The Administrator shall ensure that NASA
carries out a balanced set of programs that shall include, at
a minimum, programs in— ...
(A) human space flight, in accordance with subsection (b);
...
The Administrator shall establish a pro-
gram to develop a sustained human presence on the Moon,
including a robust precursor program, to promote exploration,
science, commerce, and United States preeminence in space,
and as a stepping-stone to future exploration of Mars and
other destinations. The Administrator is further authorized
to develop and conduct appropriate international collaborations
in pursuit of these goals."
Artemis grew out of these efforts and enjoyed fairly bipartisan support over the years (including by President Trump in his first term, see [1]).
I didn't say nor mean to imply it did. I assumed your initial question about a congressional mandate was about Artemis rather than the layoffs specifically as that's what sparked this comment chain (the wonderment at NASA spending money on Artemis and the Lunar Gateway).
> Laying off what is presumably the bottom 10% of the NASA workforce is probably a healthy decision in an environment where Butch Wilmore and Suni Williams still have not returned home.
Per the article, the 10% includes both people that have taken the deferred resignation offer and probationary employees. The former are probably generally older staff that are already considering retirement. The latter are, according to what I could find on the definition of federal probationary employees, either new hires or existing employees that were promoted or otherwise moved into a new position.
I don't see how you square that with "the bottom 10% of the NASA workforce". On the back end you're losing institutional knowledge. On front end you're losing your future contributors (see the old adage about "eating your seed corn").
Like this is what I don't get - how is it in any way fine to fire probationary employees ? Like isn't like totally wrong, rude and overall totally treating those people like garbage without any fault at their side ? What justifies such a totally insane behavior ?
How do you expect anyone willing to work four you in the future if you treat people like this...
> But with SAR you're not beam forming. You're illuminating everything - the whole ground below you. And you get a return from everywhere all at once. Two equidistant reflectors will return signals simulatenously. If your flight path is between these two points, and the distance is always equal, how can you differentiate them?
There are a couple conceptual ways to think about SAR. One is, in fact, as beamforming. Each position of the radar along the synthetic aperture is one element in an enormous array that's the length of the synthetic aperture itself: that's your receive array.
Regarding your question about scatterers that are equidistant along the entire synthetic aperture length: typically, SAR systems don't use isotropic antennas. And they're generally side-looking. So you would see the scatterer to one side of the radar, but not the equidistant scatterer on the other side.
If you had an isotropic antenna that saw to each side of the synthetic aperture, then the resulting image would be a coherent combination of both sides. Relevant search terms would be iso-range and iso-Doppler lines. Scatterers along the same iso-range and iso-Doppler lines over the length of the synthetic aperture are not distinguishable.
As to your question earlier in the chain, my preferred SAR book is Carrara et al. Spotlight Synthetic Aperture Radar: Signal Processing Algorithms. Given the title, it is of course geared toward spotlight (where you steer the beam to a particular point) rather than strip map or swath (where your beam is pointed at a fixed angle and dragged as you move along). It has decent coverage of the more computationally efficient Fourier-based image formation algorithms but does not really treat algorithms like the back projection that Henrik uses (I also think back projection is easier to grasp conceptually, particularly for those without a lot of background in Fourier transforms). But my book preference might just be because that's what I first learned with.
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