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Journal Journal: Slash-ML quotes. 11

The comment entry box proclaims that

"blockquote" Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.

, and

"quote" Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.

are accepted, but according to my regular HTML references "quote" has been deprecated (since 3.2?) for "q" Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.. So, how does Slash mangle them?

I've never used the ecode formatting before either. How does that look?

<b>"ecode"</b> Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.

.

How does that look?

So, "blockquote" indents and left-side bar ; greyed text ; "quote" indents more, left side bar, regular text colour ; "q" is ignored ; "ecode" indents, side-bars, greys, and monospaces. I'll just stick with "blockquote".

User Journal

Journal Journal: Hall of (apostrophised) Shame of editors. 43

Who can't handle "Apple-ish" funny quotes, without for one second considering the more difficult question of non-Latin characters and other HTML entities.

For clarity, the problem seems to be (not an Apple-eater myself) that Apple, with some level of automation, substitute a typographical double- (or single-) quote pair where the text file has (had) an ASCII double- or single-quote pair in it. SlashCode has more problems with HTML and Unicode entities, but this particular bug is particularly common. And annoying.

And msmash is one of the guilty parties.

How many editors are there?

User Journal

Journal Journal: new mars stuff

Another potential one from Arxiv.

Anoxic Atmospheres on Mars Driven by Volcanism: Implications for Past
Environments and Life

The current atmosphere of Mars is low pressure, but oxidising (largely because water gets split by UV high in the atmosphere, the hydrogen is lost to space but the oxygen (hydroxyl molecules) is heavy enough (has a short enough mean free path) to be retained in the atmosphere ; the iron in the surface rocks turns red (goes to +3 oxidation state). Which is well and good, and well understood. But ... oxygen does horrible things to biochemistry. Ask any SCUBA diver who has read up on the biochemistry of oxygen toxicity. While biological systems can learn how to handle having the poisonous stuff around, it needs a fair amount of biochemical machinery to contain and manage the poison. After a few hundred million years to a billion years, life on Earth managed to learn how to handle it and survived the "Great Oxidation Event". But all serious models for the origin of life on Earth depend on having initially a reducing atmosphere, unlike that of today's planet (and Mars). Mars today has no observed volcanism, but relatively fresh volcanic landforms suggests there is some volcanism from time to time. Impacts can also inject surface material into the atmosphere without active volcanism.

This study describes a model of the influence of volcanism on the oxidation state of the Martian atmosphere. A modest (more than ~0.14cu.km per year, around 1% of Earth's rate) amount of basaltic volcanism would be able to make the current atmosphere reducing, and volcanism was likely to be more common in the past, so the atmosphere of early Mars was probably often reducing, which is generally expected to be a good thing for a local origin of life. Also, an atmosphere which changed between reducing (after a large impact or volcanism) and oxidising (under the continuing influence of solar radiation) might actually stimulate the development of interesting chemistry (a.k.a "life").

Chemical signatures of previous reducing atmospheres which could be measured with current and future Mars rovers are discussed.

User Journal

Journal Journal: Confocal orbits for asteroid defence 9

Arxiv 2103.13304 "Automatic planetary defense : Deflecting NEOs by missiles shot from L1 and L3 (Earth-Moon)" proposes that

  • -1- hitting a PHA at 90deg to it's orbit is most likely to produce a large course change. I think that's pretty obvious once you look at it.
  • -2- this can be achieved at more manageable cost from L1/ L3, which are always in sight of Earth (radio communications). An elliptical orbit CONFOCAL (having the same focal points as) to the PHA's hyperbolic orbit will intersect the PHA at 90deg. I'm not entirely sure what the L1/ L3 brings to it other than relative stability and line-of-sight.
  • -3- there remains the problem of determining the PHA's orbit sufficiently accurately sufficiently soon. Time-of-flight from L1/ L3 to half-way across the Earth-Moon system remains significant, O(1day).
  • -4- Launching a salvo of missiles would produce lower risk-of-miss.
  • -5- Wouldn't a missed missile return to (close to) L1/ L3, potentially for re-use or re-fuelling?
  • -6- If so, why not produce a stream of orbiting missiles needing relatively small course adjustments to reach a PHA, so approximating a permanent defence system?
  • -7- doesn't the L1 Sun-Earth point present the same benefits ... no, we're looking at PHAs which may impact the central body, and we don't care about rocks hitting the Sun.
  • -8- You'd need two streams of missiles in clockwise/ counter-clockwise orbits to reach most orbits efficiently. Would you need some at moderate inclinations to cover out-of-Fundamental Plane objects? Or ... the contra-rotating missile streams being at 45deg to the Fundamental Plane to cover both options.
  • -9- Somewhat related, what would be the benefits of Earth-Sun L4/ L5 points for positioning earth-scanning telescopes to scan for PHAs.
  • -n-

The detailed paper (Acta.Astro 50 185 (2002) is hidden and SciHub blocked now. Asked author for a copy (ore re-post yo Arxiv?). Need a VPN.

Slashdot.org

Journal Journal: Politics and moderation.

Doing some moderation and getting extremely pissed off by the endless maundering of (presumed) Americans about some internal political matters. Someone called Kerry Dubyah is contesting with someone called John Bush for the leadership of some body called POTUS (sometimes a related position called FLATUS is also brought into the "debate" to confuse matters. this post seems to be related to the gigolos/ babotchkas that the contestants use/ are used by. I think.)
I'm wishing for a moderating flag like "Parochial Politics" that would come at a level like "-99", so that such comments could be killed off at source, leaving the interesting (to nerds - this is "News for Nerds, stuff that matters" after all) stuff like the trolling, the flamebaits and the actual technical stuff where people can find it without wading through the dross. Might be able to get rid of the Iraq dross through the same method.

But how to put this forward to the "system" as a proposal? Still can't find a place to post such suggestions/ requests.

The idea is not /quite/ comparable to moderation though - things can move up and down a scale in the moderating system, but I envisage this as being more like a permanent flag. Sort of like the "green beard" method described by W.D.Hamilton.

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