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Comment Since nobody is going to mention what was found: (Score 5, Informative) 28

Past studies:

* Volatile, low-mass (100 u) nitrogen- and oxygen-bearing organic species.

* Single-ringed aromatic compounds.

* Complex, high-mass (exceeding 20 u) macromolecular fragments of insoluble organic material, featuring multiple aryl groups connected to hydrocarbon chains, along with nitrogen- and oxygen-bearing groups.

* Aryl (aromatic) and oxygen-bearing compounds in older E-ring grains.

Current study:

* Confirmed aryl and O-bearing compounds in fresh grains (ruling out that they formed due to space weathering)

* Aliphatic O-bearing compounds with carbonyl groups attached to a C2 organic, with acetaldehyde or acetic acid being likely candidates (aldehydes are interesting because they're intermediates precursors in the formation of amino acids)

* Aliphatic and cyclic esters and/or alkenes (on Earth, these are involved in the formation of fats and oils)

* Two classes of ether and/or ethyl compounds (on Earth, these are regularly found in living organisms)

* Tentative N- and O-bearing moieties. Potential candidates for these molecules include derivatives of pyrimidine, pyridine, and nitriles like acetonitrile (such molecules are involved in the reactions that form amino acids).

TL/DR: there may well be not just the atomic building blocks of life in there (CHONPS), but the molecular building blocks as well.

Comment Re:Evolution speaks (Score 1) 50

EVERY point you mentioned has a genetic component.

Menopause has a genetic component? Exactly how much are you planning to reengineer the human race?

The few times its not (environmental causes I suppose) is incredibly rare.

... says PDXNerd, responding to a post where the vast majority of cases listed are predominantly environmental.

If you want to be pedantic, you can probably "find" genetic susceptibilities to literally anything, even dying of a car accident. But you're not going to blame a person dying in a car accident on their genes. It's not even close to the proximate cause.

You literally said "genetic component" or "genetic factor" on every point

I "literally" did not.

PLEASE we do NOT need more old people having babies

Why? No, seriously, why? Because anyone over 50 grosses you out? If you're so obsessed with genes, you should be thrilled with the concept of older people having babies - the older the better! It means they've survived later into life. You should want 90-year-old grannies having as many children as they can.

The low birth rate in western countries

I can't tell if you want to fix it or not.

there's plenty of children that need fostering and adopting.

You could not possibly be more ignorant on the topic. This isn't the 1850s, with orphanages full of orphans just down the street, waiting for someone to show up and sign some papers. There's too much competition for too few children, and it's a bureaucratic nightmare. The average adoption costs $20-50k and international adoptions (most adoptions these days) take on average 2-4 years, but complications can drag them out to far longer - and all the while, the child is growing up without you. It's a massive emotional burden on any prospective parent. Actually talk to any adoptive family before spouting such nonsense.

Comment Re:All that poison people eat and smear on their s (Score 1) 170

Fun fact: the genus name for meadowsweet / mead wort (a plant of waterlogged soils that grows a lot near me), used to be "Spirea". It's a traditional flavoring herb and strewing herb, but also common in herbal medicine. Its traditional medicinal uses were confirmed in the late 1830s when salicylic acid was extracted from it. So in the late 1800s when Bayer started making "acetyl spirea" extract, they named it "aspirin".

Comment Re:All that poison people eat and smear on their s (Score 1) 170

The VOC thing is technically true, but not in practice. It's based on NASA studies in enclosed chambers, but the effect is small enough that it's not meaningful compared to a house's natural ventilation. And plants can also release their own VOCs (though again, very small quantities unless you've turned your home into a forest)

That said, houseplants do two things that help improve air quality:

Humidity: most homes with climate control are too dry (both heating and air conditioning can lower relative humidity). Dry air leads to nasal /throat irritation, nosebleeds, skin and eye irritation, chapped lips, increased susceptibility to pathogens (dried out mucous membranes), longer pathogen lifespans, worsening allergy and asthma symptoms, increased static electricity, wood cracking, and other issues. Plants are natural humidifiers; the loss of large amounts of moisture to the air is an essential part of how they work, and all of the water that you pour in their pots ends up in your air.

Dust removal: not through any sort of fancy process, but simply because plants present very large leaf surface areas that attract and retain dust. When the leaves are shed or water falls on them (or they're wiped down), dust is lost from the system.

A number of studies also strongly suggest that having plants around is just simply good for your psychological well-being, especially in the winter.

Comment Re:All that poison people eat and smear on their s (Score 1) 170

Yeah, I'd advise "natural" people some day to pick a dozen or so spices they like, look up what chemicals comprise the essential oil that give them their aroma and flavour, and then look up each of those chemicals. It's a laundry list of toxins, allergens, carcinogens, mutagens, etc etc.

Thankfully, it's the dose that makes the poison, and most people don't use enough spices to cause a large risk. But "natural" does not mean "safe".

As a side note, I hate the category "ultraprocessed food". If a food contains, for example, whey and has at least five ingredients, that's a NOVA category-4 ultraprocessed food. A large chunk of baby food is "ultraprocessed", and all infant formulas. Specific means of processing are dangerous, and we need to be calling out those specific means, not lumping all forms of processing together. For example, smoked meats adds carcinogens, cured meats adds nitrates / nitrites (carcinogenic), hydrogenation adds trans fats (though the situation is much better than it used to be), etc.

Any food grouping that clusters together bread, ice cream, artificially sweetened yogurt, and vodka in the same category is a nonsensical food category. One of the main goals of food science over the past century has been to break down categories. E.g. moving on from:

"Fat is bad!"
"Well, *saturated* fat is bad, non-saturated fat is good!"
"Well, *saturated fat* is bad, polyunsaturated fat isn't great, mono-unsaturated fat is good!"
"Well, re polyunsaturated, the omega-3s are good but too much omega-6s are bad - and also, trans fat is really bad!"
"Well, *this particular* fatty acid..."

The whole concept of ultraprocessed foods is a huge step in the wrong direction.

Comment Re:Evolution speaks (Score 4, Informative) 50

"unless we can also correct flaws in the DNA that does not allow them to have children"

Why on Earth did you just assume that they can't have children because of "flaws in the DNA"?

First off is a source of complete infertility which *every* woman encounters unless she dies young: age (menopause). As for non-age related causes:

Of partial infertility, the most common cause (~80-85% of cases) is PCOS. Literally 5-10% of women in the US of reproductive age have this. There is a genetic component, but environmental factors are probably the biggest contributor (it's on a hormonal axis that includes diabetes, and is related to excess weight, stress, etc, but also has some mild intersex characteristics, such as high testosterone levels, high AMH, etc; there's an interplay between hormones that's out of balance)

Other causes: uterine fibroids and polyps, endometriosis, etc.

Of full infertility: bilateral tube blockage is a relatively common one, such as from pelvic inflammatory disease (often caused by STDs), previous surgeries, past ectopic pregnancy, etc.

Primary ovarian insufficiency: either hitting menopause young, or never having normal ovarian function. Some causes are genetic, others are not - for example, cancer treatment.

Absence of a uterus: sometimes genetic, by far more common is due to hysterectomy (for a range of reasons). Though of course this would preclude pregnancy from this technique as well.

Genetic conditions that lead to streak gonads (undifferentiated between testes / ovaries) or the absence of ovaries, though these are rare.

So yes, genetic factors *can* be a cause of infertility, but far more common is non-genetic factors.

Comment Re:I am rooting for Blue Origin now. (Score 1) 31

And here is the problem: you're so bad at social interaction that you can't tell the difference between a rebuttal and "rage". You have some sort of fantasy about someone on the other side of the world smashing their keyboard and stewing over your words all day.

I hate it to break it to you, but that's just your pathetic imagination.

Comment Re:I am rooting for Blue Origin now. (Score 3, Informative) 31

I take it you believe the Apollo program shouldn't have happened

What did you pull that out of? The technology was nowhere near mature enough back then. That doesn't change the economic picture of throwing away your entire rocket every flight.

(We can argue whether "flags and footsteps" were worth spending an amount of money best measured in a percentage of your GDP, but that has nothing to do with the reuse question)

Next up

Lol, "next up"? You clearly think you hit your straw man out of the park ;)

since return is paramount - are you in agreement that only launch envelopes that allow return hold be allowed

"Be allowed"? Do you do anything other than straw men, or is that literally the only way you know how to carry out conversations on the internet?

SpaceX "allows" anyone to choose a disposable mission. Almost nobody chooses that because reuse is cheaper. In general, the only times when disposal is chosen is when there is literally no option but disposal in order to meet the spacecraft's performance needs.

Again: if you were given a choice when buying a plane ticket, either it can be cheap, or it can be expensive because they're going to wreck the plane specifically on your behalf, unless you had some really pressing need to wreck the plane, you're not choosing that option.

As a smart person who understands orbit mechanics

As an internet asshole, do you know that you actually have the option to not be an asshole online?

you do know that only very specific launch envelopes allow return.

First off, it's not even clear what you're referring to with "return". Boosters don't even reach orbit, so bringing up the concept of launch envelopes and return from them related to "orbital mechanics" is ill-formed. Booster return is entirely contingent on whether the payload needs an extreme level of performance beyond that which the system can meet with reuse, e.g. whether they absolutely have to remove the landing legs and grid fins to lighten the booster and burn every last drop of propellant. Only an extremely small fraction of launches fit into this category. Falcon 9 - the vehicle in question - only does booster return, so this conversation ends there.

If we want to talk about something other than F9, like, say, Starship, saying "only very specific launch envelopes allow return" is also wrong - again, unless your payload needs so much performance that the upper stage will not reenter the atmosphere (or you deliberately designed a trajectory to specifically make the stage come in hard). Their TPS design goal is to be able to burn off the heat of even mars transfer orbits. Now, one can argue that they'll fail in that goal, but you need to list your assumption of failure as a premise. Regardless, though, unless the entire project is a failure, the upper stage will handle return all "normal" Earth orbits. It has on-orbit reignition and can target its entry trajectory.

If a falcon 9 or heavy needs to go to a different orbit, it has to be abandoned

Again, this makes no sense. Are you positing launches where they change their mind partway through ascent or after it reaches orbit? "Nah, we don't REALLY want it in that trajectory, let's do a different one!"?

In the real world, again, the only times they expend a booster is when the performance needs of the payload are beyond what they can deliver in reusable mode, even with Falcon Heavy (or occasionally for testing, etc). And the upper stage of F9/FH never returns, because it can't, so it's not part of the discussion (they've done some work on trying to make it recoverable, but in each cases it was a "better to put the effort toward Starship" situation... which is IMHO kind of a shame, in that I'd love to see the maturation of e.g. inflatable entry systems, one of the possibilities they were considering).

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