Comments of the Week #147: from spacetime's nature to the strangest moon of all

"Sometimes I even now feel like a stranger in my country. But I knew there would be problems because I had seen the world... Freedom is good, but it is not easy." -Katarina Witt

Yes, as always, as another week goes by at Starts With A Bang! there have been a huge number of great stories we've covered. In addition, we've now recorded sixteen Starts With A Bang Podcast episodes thanks to your Patreon support, and if you're local to the Pacific Northwest, we have some fun events coming up, including a public talk at 7:30 at OMSI on February 20th on the controversy over the expanding Universe, a Guest of Honor appearance at NorWesCon in April, and I'll be at Brooks Winery in the path of the eclipse for the big event in August! That said, let's take a look back on this past week of incredible science stories:

There's so much to get to let's not delay, and instead dive right into our comments of the week!

The 'institute of noetic sciences', or IONS, is a good example of counterfactual information. Image credit: screenshot from http://noetic.org/. The 'institute of noetic sciences', or IONS, is a good example of counterfactual information. Image credit: screenshot from http://noetic.org/.

From CFT on redefining words: "Facts are easy, you just remember them. Determining if they are actually true or not is another matter altogether."

No. A fact is not "something that you're told/taught that you remember and regurgitate." That might be how you get your facts, but being told or taught something doesn't make the thing you're told factual. The veracity of the thing being told determines its factualness. And so many of us want a quick and easy answer that we can agree with that we often choose non-factual information (or incomplete facts, or counterfactuals) to confirm our own preconceptions. If you think "oh, I'll just remember this fact" when you encounter some information, you're not fact-finding at all.

Heat-trapping emissions (greenhouse gases) far outweigh the effects of other drivers acting on Earth’s climate. Source: Hansen et al. 2005, Figure adapted by Union of Concerned Scientists. Heat-trapping emissions (greenhouse gases) far outweigh the effects of other drivers acting on Earth’s climate. Source: Hansen et al. 2005, Figure adapted by Union of Concerned Scientists.

From dean on climate science: "The evidence for climate change is overwhelming, as studies and data continue to show, but the communication of that fact has been poorly done – hence the anti-science folks claiming Mann’s analysis has never been supported, or is flawed, or the asinine “sample size of 1” argument the very desperate deniers use."

From a scientific point of view, the communication has been very well done! It's been straightforward, accurate (where about 5-10% of claims are overblown and 5-10% are far too mild, with 80-90% right in the mainstream), representative of scientific thought and publicly available. But the disinformation campaign has been extremely successful among a large segment of the population. I do think it's as simple as that. Add in political bias/polarization, ideology, tribalism and money equaling speech, and that gives us our situation today.

Warming rate of the Earth, as of 2011, and how it changes depending on which start year you choose. Image credit: tamino of http://tamino.wordpress.com/2011/10/30/judith-curry-opens-mouth-inserts-foot/. Warming rate of the Earth, as of 2011, and how it changes depending on which start year you choose. Image credit: tamino of http://tamino.wordpress.com/2011/10/30/judith-curry-opens-mouth-inserts….

From Denier on those lying climate scientists: "This same sample size limitation affects many aspects of Climate Science which is why Climate Science is so reliant on computer models. Those simulated planets are not yet perfect. They make predictions, but those predictions have sizable error bars because the Scientists know they’re not perfect. The deviation between projection and reality is a common soft target, and Ethan has written in defense of the predictions many times summing it up as ‘you just have to be honest about the error bars’.
Climate Scientists are not honest about the error bars."

That there are uncertainties -- quantified accurately in the literature and in the models (i.e., your dishonesty claim is false) -- does not mean the consensus predictions are unreliable. That we have to rely on simulations to understand the climate does not mean the simulations are unscientific or unreliable. This is the difference between science and politics, where in the latter case you make your story full of convincing-sounding points that don't reflect the scientific truth. For example, here's what Drew Shindell said about the (false) claim that maybe human's aren't the main contributor to Earth's warming, which is still being debated, publicly, by large swaths of the country:

Of all the natural drivers, and everything we know that works on long time scales that has ever affected climate in the past, all those things have been ruled out. Beyond a reasonable doubt, it has to be human activities.

So if you want me to call out people when they tout incorrect, misleading or just wrong information on all sides -- and to correct my own mistakes when I make them -- which I have a long record of doing, you should be consistent and do the same. For the people "on your own side" and for yourself. If you're TL;DR-ing, yes, there are uncertainties, no there's no dishonesty about it, and no, the uncertainty about the models' predictive power doesn't change the conclusion about what's real, what its cause is, or what the future holds if we do nothing.

The fabric of the Universe, spacetime, is a tricky concept to understand. But we're up to the challenge. Image credit: Pixabay user JohnsonMartin. The fabric of the Universe, spacetime, is a tricky concept to understand. But we're up to the challenge. Image credit: Pixabay user JohnsonMartin.

From John Duffield on whether space or spacetime is curved: "the article says “curved space” when it ought to say curved spacetime. The space around the Earth is not curved, instead it’s inhomogeneous, and when you plot the inhomogeneity, your plot is curved."

Hi John, long time no see. Or rather, long time without hearing you talk about the difference between space and spacetime, which you are sometimes correct about and sometimes not. In this case, you're not.

Both space and spacetime can be curved, both mathematically and physically, as in General Relativity. Jonah Miller has an excellent post about geodesics, spacetime's curvature and how that manifests gravitationally. Yes, spacetime is curved; yes, space is inhomogeneous around Earth. But also, the space around Earth is curved as well, which is why light rays are deflected by masses in this Universe. The article could have said curved spacetime and would also have been correct, but curved space is absolutely right. If you don't believe me, do the 3+1 decomposition yourself in a weak gravitational field (or Schwarzschild space, if you prefer) and see for yourself!

Four gas giants orbiting the star HR 8799. Image credit: Jason Wang / Christian Marois. Four gas giants orbiting the star HR 8799. Image credit: Jason Wang / Christian Marois.

From CFT on failed stars and binary systems: "I remember at one time Carl Sagan said that gas giants were failed stars…and that many solar systems were binary. Are binary star systems then both ‘cooler’ stars since both stars are basically hydrogen? Or is there evidence of a mixed binary system where one can be hot, the other cool?"

The temperature of a star, to an excellent approximation, is determined by its mass. How successful (or unsuccessful) you are at becoming a star determines what your mass is. You can have mismatched binaries where one is cool and one is hot, you can have equally successful binaries of nearly the same mass, or you can have the situation we do here: where Jupiter is the closest thing to a failed star we have, but it still needed about 70-80 times its mass if it wanted to become a star. There are a lot of "chances" in the Universe, and nature exhibits a wide diversity of systems that it delivers to us.

Image credit: Amy S. Lo et al. (2010), from the Starshade Technology Development Astro2010 Technology Development White Paper. Image credit: Amy S. Lo et al. (2010), from the Starshade Technology Development Astro2010 Technology Development White Paper.

From PJ on being amazed by what we can see: "Friggin amazing what we are able to see at the present. The near future will be even more spectacular; given higher resolution means."

This direct imaging technique is incredible, but it relies on a coronagraph, which blocks the light from the parent star but creates a diffraction pattern around it that makes only the largest, most well-separated planets directly visible. The next advance is to create a starshade in space that can fly at an extraordinarily large distance from a space telescope, upping the contrast from about 10^6 to 10^10, making planets 10,000 times as faint visible. Earth-like planets in the habitable zones of stars, here we come! Coming, NASA-funding and prioritization dependent, to either the 2030s or, potentially, WFIRST in the 2020s if we get lucky!

The XKCD version of Free Speech. Image credit: xkcd/Randall Munro, from https://xkcd.com/1357/. The XKCD version of Free Speech. Image credit: xkcd/Randall Munro, from https://xkcd.com/1357/.

From Denier on free speech: "One of the most contentious speakers on the college circuit right now is Milo Yiannopoulos. For those unfamiliar, Milo is a conservative, white gay male who exclusively dates black guys. His lectures are often anti-Feminist, anti-Safe Space, anti-Identity Politics, and religiously bigoted against followers of Islam.
Milo is not Fascist. He’s not a Nazi. He’s not Alt-Right. He’s not racist. Milo is not a White Nationalist.
https://www.youtube.com/watch?v=ywmd8kR-AmI
Wherever Milo Yiannopoulos speaks, protesters come out in force to try and shut down his lectures. They carry signs and chant various accusations of Fascism along with all of the above. These charges are directed not only at Milo but at anyone going to see Milo."

The last time you brought up free speech issues and the first amendment (no idea why it's being brought up here, but whatever), I cautioned you against strawmanning my position and encouraged you to steelman me instead, or at least take what I say at face value. But we're back to strawmanning, I see.

You are welcome to tell me what you think Milo is or isn't, but I am not so old that I don't remember being the ages of 10-13. Where kids first became mean, violent and cruel to one another not to sate their own personal needs (money, candy, the thrill of violence, etc.), but to gain social status instead. I don't care why Milo does what he does or says what he says; what I see is someone who's a minority in one way (he's gay) bully and beat down people -- in a public forum -- who are minorities in ways he is not. Who are not part of his in-group. He bullies trans people. He bullies muslims. He bullies women. He bullies poor people. And he does it knowing full well that this is his ticket to (partial) acceptance and (loud) adulation within his in-group. Which includes all of the people in the "Milo is not..." groups you list above.

I disagree with Milo in almost everything he's ever said. I support not inviting him to your campus. I support protesting his appearance. You know, exercising your right to free speech. But I don't condone the violence in the protests against him. I condemn the actions of the black bloc protesters, as do most people across the political and ideological spectrum. I also don't conflate "liberals" or "progressives" with a violent minority, just as I don't conflate "muslims" with the radical islamic terrorists or "actual Nazis like Steve Bannon" with everyone who voted for Donald Trump. I hope you can stop conflating an article that contends, "scientists should adhere to this simple code of ethics in their scientific pursuits and their presentation of science to the public" with a loss of your first amendment rights to act as a private citizen.

But I think your real point comes a few comments later: "The idea Ethan keeps coming back to lately is how to oppress society."

Society is doing a great job of oppressing a large number of its members. That is an injustice that I see that I believe needs to be righted. So let me ask you what you see as positive ways forward on that front, since elevating those marginalized but valuable voices equals oppression to you. How do we ensure that racial profiling stops? How do we protect the rights of women to control their own bodies: specifically for contraception and access to abortion services? How do we protect rape victims from being further victimized by the legal process? I am starting to think that you and I have very different views on what a "right" is, and that may be the root of where we differ on oppression as well. There is room to argue about that, I suppose, but I think it goes back to something that Donald Trump said in his inauguration speech.

"הִנֵּה מַה-טּוֹב, וּמַה-נָּעִים--    שֶׁבֶת אַחִים גַּם-יָחַד."

Do you recognize that? It's Psalm 133, my favorite of all the Psalms. (Trump read a translation of it at the inauguration.) Literally, it means "how good and how blessed it is when brothers can live together as one." I think if you interpret brothers as "people like me" or "my actual brothers" or "the people on my side but not the ones not on my side," you miss the meaning of "together as one." We are all children of planet Earth, and I want to see a better planet and a better future for us all. For. Us. All. That is what I'm working to build.

Pan-STARRS1 Observatory atop Haleakala Maui at sunset. Image credit: Rob Ratkowski. Pan-STARRS1 Observatory atop Haleakala Maui at sunset. Image credit: Rob Ratkowski.

From Wow on collecting every photon: "But not even the best black coating can capture every photon.
Not that every one is required."

There is a difference between collecting and utilizing. It's worth remembering that telescopes have not increased all that much in size over the past 100 years. The telescope that Hubble used to discover the expanding Universe -- the 100 inch (2.5m) Hooker telescope -- is larger than the Hubble Space Telescope's primary mirror. It was commissioned in 1917. One twice the diameter (the Hale telescope) was commissioned in 1948, and today's record holders are about twice that diameter still. But the big improvements are in CCDs and cameras. Instead of collecting between 0.1% and 1% of the light, which is what old photographic plates did, we can now use the technique of photomultiplication -- where photons strike a surface and an electron gets kicked or excited, creating a cascade and an unmistakable electric current -- to efficiently use about 20% of the incident light.

But there is still noise, and that makes the signal hard to pull out of the noise. Once you know where and how something exists, you can go back and clearly pull out a marginally statistically significant signal that would have been ambiguous previously. After the 2011/2012 discovery of the Higgs, they were able to go back to 1988 Fermilab data and identify the first Higgs event; going back through telescope data is a similar process. As time progresses, materials science improves and gets applied to camera technology, we hope to come ever closer to the 100% goal. But noise will always be present.

Light coming from the surface of a neutron star can be polarized by the strong magnetic field it passes through, thanks to the phenomenon of vacuum birefringence. Detectors here on Earth can measure the effective rotation of the polarized light. Image credit: ESO/L. Calçada. Light coming from the surface of a neutron star can be polarized by the strong magnetic field it passes through, thanks to the phenomenon of vacuum birefringence. Detectors here on Earth can measure the effective rotation of the polarized light. Image credit: ESO/L. Calçada.

From Anonymous Coward (and echoed by Sinisa Lazarek) on the weird vacuum birefringence effect: "By the way, does the very powerful magnetic field actually change the polarization of the light from the neutron star? As the abstract indicates the emission of light from the neutron star is thermal and thus it should be emitting light at all wavelengths and polarizations. Does the magnetic field actually change the polarization of the light as it leaves the star, or does it have an effective polarization-dependent refractive index, the way a birefringent crystal like calcite does? The article seems to indicate the former, but I’m not sure this is true."

There is another, older effect which we see all the time: Faraday rotation, which explains how magnetic fields in a medium cause the polarization of light to rotate in a particular fashion. You can measure galactic magnetic fields this way by looking up, away from the galaxy, then moving down, down, down, into the galactic plane, and then out again, and looking at how the polarization of light changes. But this only happens in a dielectric medium, and tells you the combined properties of the magnetic field and of the free (ionized) electron content, which are primarily responsible for the Faraday rotation itself.

But this effect, of vacuum birefringence, is non-classical and purely quantum in nature. It is a much more subtle effect that is similar, but occurs in empty space itself. Yes, the magnetic field actually changes the polarization of light, and it is wavelength dependent. Were these X-rays instead of visible light, the polarization would be ~100% instead of ~15%. It's an incredible confirmation of this quantum prediction.

The two-toned Iapetus is the strangest known moon in all the Solar System. Image credit: NASA / JPL-Caltech / Space Science Institute / Cassini. The two-toned Iapetus is the strangest known moon in all the Solar System. Image credit: NASA / JPL-Caltech / Space Science Institute / Cassini.

And finally, from Sinisa Lazarek on Iapetus: "The first thought that came to mind when I saw the first image is: Rolling stone gathers no moss"

That's actually quite a profound thought, and speaks to the point that Iapetus is tidally locked. If Earth orbited Saturn at the distance of Iapetus, it would be locked, too. This is very meaningful when you consider potentially habitable planets orbiting M-class stars; they're all locked as well. The timescale to locking is very short for these worlds: 10^5 to 10^7 years, while our Solar System is billions of years old. If Iapetus weren't locked, it would be more uniformly covered in Phoebe's soot, except for at the poles. As it stands, you can conclude quite clearly that this planet isn't rolling, and it's a demonstration of the incredible power of tides.

Thanks for a great and thoughtful week, and looking forward to the next one!

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what I see is someone who’s a minority in one way (he’s gay) bully and beat down people — in a public forum — who are minorities in ways he is not. Who are not part of his in-group. He bullies trans people. He bullies muslims. He bullies women. He bullies poor people. And he does it knowing full well that this is his ticket to (partial) acceptance and (loud) adulation within his in-group

And this is what Ben Carson is doing too. He makes up fake stories about how bad and evil and horrible he was as a black kid, as all blacks are, until he Found Jesus and saved from his sinful nature by the blessed White Christians.

They LOVE that BS.

And rather more sadly, it's what Sammy Davis Jr did to get accepted and stay accepted by society. As long as he played whatever second fiddle the rest of the Rat Pack was, and knew (and kept) his place, acting their buttmonkey on demand, he was accepted by the industry who were more afraid of the Rat Pack than they loathed a black performer doing well.

And Judith Curry has been doing it for years for the AGW deniers. She has found the recognition and adulation she KNOWS she deserves, as long as she keeps peddling false uncertainty for AGW deniers to accept and parrot.

Space-time is abstract. A non-linear abstract. Categorically and demonstrably.

By Simon Morley (not verified) on 05 Feb 2017 #permalink

re #2, utter rot, simon

Ethan, you state that we can use photomultiplication to detect 20% of the incident photons. Well, we can use photomultiplication, it's true, but the best CCDs these days can record of order 80% - 90% of the photons which strike them, without photomultiplication.

It's very nice for us observers.

By Michael Richmond (not verified) on 05 Feb 2017 #permalink

@Ethan wrote

I am starting to think that you and I have very different views on what a “right” is, and that may be the root of where we differ on oppression as well.

I believe this to be an accurate statement. A “right” is a legal entitlement. My interpretation of the First Amendment is along the same lines as the ACLU’s. You’ve admitted in the past that you don’t really understand it as it is not your field of expertise. No problem. A lot of people can’t back up any of their positions with any sort of substance. That is normally not you. In most of what you state, you are as deep as it gets. As you say, you can take an opponent’s argument, fix their problems, and still beat them into the ground all while being perfectly civil. Not so when it is “a right” that is at issue. You resort to strawmanning and ad hom attacks. We do seem to have a different view on what a “right” is, and you may want to entertain the notion that your ‘admitted as uninformed’ view is wrong.

@Ethan wrote

Society is doing a great job of oppressing a large number of its members. That is an injustice that I see that I believe needs to be righted. So let me ask you what you see as positive ways forward on that front

First and foremost:

הִנֵּה מַה-טּוֹב, וּמַה-נָּעִים– שֶׁבֶת אַחִים גַּם-יָחַד

It’s Psalm 133, one of your favorite of all the Psalms. Literally, it means “how good and how blessed it is when brothers can live together as one.” I think if you interpret brothers as “people belonging to an identity group” or “Scientists” or “Minorities”, you miss the meaning of “together as one”. You get so busy dividing people up out of some moral duty to help those you see as less fortunate, or in the case of Scientists, more intellectually fortunate that you’ve completely lost sight of the fact that you are dividing people and have no real endgame for how to later undivide them.

Regardless of the original intent I find divisions in society to be ultimately harmful. We should live together as one. Societal balkanization is cancer. My positive way forward is to exercise my voice when I find people trying to divide us.

Oh god, the Holy Saint gambit. From *Denier*.

FFS.

Ethan has clearly stated how denier is habitually dishonest in his statements. It is no surprise denier claims he hasn't been and tries to claim the high road.
Time to simply ignore him, with the realization that his position isn't based on science, it's based on his agenda.

@Denny #5
"We are all children of planet Earth, and I want to see a better planet and a better future for us all. For. Us. All. That is what I’m working to build."

There is no mention of division, or class identification in Ethans piece.
Hopefully, most of us are pushing in the same direction for universal "brother/sisterhood".

@#4, M.R.
Is that in real time, or by photographic means?

@ PJ

Michael is correct, and it is in real time (hence you can see on your screen what is that you are shooting). Silicone does have some 70-80% sensitivity to photons hitting it, in comparison to several % that photo plates had.

On the other hand... there is a place where Ethan's 20% comes in.. and that's when you cover all that silicone with a grid to carry those electrons, what you in effect do is mask the silicone.. and now you get something which has most of it surface covered and is now actually being able to "see" only about 20-30% of the photons incoming (think about putting a 2 inch thick grid on your window. But that's not the finished CCD. After that, super-tiny lenses are placed at every "open" space on the silicone, but in such a way that they overlap over the grid, gathering the light that would fall on the grid and be wasted. With lenses, it returns back to 70-80%

By Sinisa Lazarek (not verified) on 05 Feb 2017 #permalink

"@#4, M.R.
Is that in real time, or by photographic means?"

B&W CCDs optimised for optical use are up to 90% efficient, and colour ones are somewhere around 60% efficient over the nominal band peak.

And the gain applied to CCDs (including in your DSLR) can be increased so that either less than one electron per photon is counted as a "+1" all the way up to +lots for one electron.

One of the problems I have with DSLR docs is that the ISO rating, which is really just a "photographer-ready" measure of gain isn't given as which setting gives 1:1. Any less than that and you "lose" photons, since they don't create another +1 to the image total exposure for that pixel. Any more than that and you're not increasing the resolution, you're now counting more than +1 to the total count for the exposure.

It is the gain that Ethan is talking about,I think. Unless it's the loss rate not sure.

But the photo electric effect produces 1 electron per photon it captures, And whether an incident photon produces an electron is the quantum efficiency.

Whether that produces another +1 in the count or not is gain (times efficiency) not efficiency.

SL, at low light levels the problem isn't efficiency, it's efficiency to an exponent.

The silver halide crystal is supposed to irreversibly change state when hit by a photon of the right wavelength (and being a solid, this is actually a band of wavelenghts, doping of the gel restricts the amount of photons getting through, mostly outside the nominal doping colour band). But a single photon hit won't do it. It will naturally relax back into its own state within a certain amount of time, and needs another photon to hit it while in this excited state to actually flip.

That is irrelevant in the photon-rich environment of daytime or flash photography. Even dim lighting is fine, plenty of photons to play with per crystal (indeed it is partly because of this requirement that finer grains are "slower" film).

Hence in the days of astrophotography, a subject half as bright would take 10x as long, and what today takes 10-20 minutes to expose on a 90% efficient CCD took days of exposure (at several hours per night) to get the random chance that another photon would come along quick enough to flip the crystal.

What they used to do was chemically treat film beforehand to put them on the brink of changing so that the exposures would reduce by a large factor.

But CCDs allow much much MUCH fainter objects to be detected because their response is linear to light as opposed to logarithmic (at low light levels) for photo emulsion.

I could dig out my old astrophotography book and get a couple of examples of how film exposure times changed per apparent magnitude if you like. Should be able to dig it out.

Ethan: I think if you interpret brothers as “people like me” or “my actual brothers” or “the people on my side but not the ones not on my side,” you miss the meaning of “together as one.” We are all children of planet Earth, and I want to see a better planet and a better future for us all. For. Us. All. That is what I’m working to build.

Denier's straw man version of Ethan: You get so busy dividing people up out of some moral duty to help those you see as less fortunate, or in the case of Scientists, more intellectually fortunate that you’ve completely lost sight of the fact that you are dividing people and have no real endgame for how to later undivide them.

Good lord, man! How you turn someone's own sentence around so badly without feeling a sense of shame? How exactly did your eyes see "all children of Earth" and "For. Us. All." and yet your brain translated these actual words into "dividing people up" in your head?

Thanks, SL.
I remember the days well using 400 asa film blown to 1600, sometimes to get a little more out of a shot. Today, of course, stacking many shots pays dividends.

@ Wow
"I could dig out my old astrophotography book and get a couple of examples..."

Sure, that would be great! :) Don't know that much about pre 80's astrophotography. I have a Will Tirion Sky Atlas 2000 deluxe from 1981 on my bookshelf.. but that's about how far my history of astronomy goes in terms of actual printed material. Nowdays Stellarium does same and much more, so haven't really picked the atlas in 15 years or more.

@ PJ
signal-to-noise is IMO today's biggest hurdle. Just the difference between a summer astrophoto and a winter one in terms of noise on the CCD is tremendous. Hence the cryo cooling of pro ccd's. But stacking helps a lot. 200 photos of 1s exposure stacked, will generally give a better result then a single 200s exposure, if shooting with a dslr. Cooled CCD's can handle more exposure ofc... but after several hours, I think light polution slowly starts to set the upper limit of what you can get (talking for us amateurs ofc.. who don't have a scope on mount whatever 400 miles from a first lamp post :D)

By Sinisa Lazarek (not verified) on 05 Feb 2017 #permalink

This is what I've got for Kodak's B&W film. This is jotted down from their spec sheet, since there's no such film any more (though kodachrome is still going strong, and quite fast too. But now FAR too expensive to use. Even my dad now uses his Nikkon DSLR).

If you are looking for the data itself, look for "Reciprocity factors". Expressed in stops. For astrophotography, you have it wide open anyway (or it's prime focus so you have no stop to change), so you need to increase the exposure instead

For an exposure (shutter) time of 1/10s or less, no change.
For 100s exposures, you have to either open up 3 stops or increase the time by a factor of 12.

A bit of googling brought up this table for several films

https://mkaz.com/film-reciprocity-tables/

culled from people's information rather than from the various sites, because these are often not on the internet or have been retired as film stock changes.

You may find your film stock in there, if you have it.

Re: dark skies, a faster scope may be what you don't want, since the light collection is from a wider sky.

Figures for brightness for astronomy tables don't work for extended objects, because they use integrated (total area of object) brightness, which also makes for a variation in catalogue brightness for extended DSOs. Include the fringes or cut more of the edge out changes the integrated brightness of an object given.

they may be on another revision, but The Observer's Sky Atlas by E Karkoschka, ISBN978-0-387-48537-9 gives the per-solid-arcsecond brightness and the equivalent values for the sky with various phases of the moon for reference: if the object is darker than the sky, you won't be able to see it since it won't be much brighter than "empty" sky.

Sinisa #10,
CCD's are not made from silicone. Some of them are made from silicon, which is a semiconductor. Silicone is an insulator, and is the rubbery substance used to seal around windows and bathtubs.

@ ketchup

thank you for spellchecking. they are made from silicon, not silicone.

By Sinisa Lazarek (not verified) on 06 Feb 2017 #permalink

@PJ wrote:

There is no mention of division, or class identification in Ethans piece.

In the 'Psalm 133' paragraph, you're absolutely right. Ethan said nothing of division. The reason I chose to so closely mirror his prose was to highlight how inconguent it was with some of his other writings.

One particular example was the sentiment expressed in his piece titled 'The two questions that determine your scientific literacy'. It was essentially elitism. In that piece, there were 3 divisions: 1-Scientists, 2-The Literate(non-Scientists who worshiped group #1), and 3-The Non-Literate. In CotW#144 Ethan affirmed it. Specifically he wrote:

And finally, from Denier on cutting right to the chase: “When you get right down to it, this is just more elitism.”

Yes. Yes, you said it, and this is right.

This is far from the only example in Ethan's writings, but was the reason for the inclusion of 'Scientists' in the Psalm 133 paragraph. For a while last year or the year before he was on a kick of protecting women. Ethan seems to see divisions in our society and wants to help those he sees as less able to protect themselves. Ethan's musings are those of someone who seems himself as privileged and wants to use that privilege in the service of moral good. It is a noble sentiment and I believe Ethan to be a good person. I'm not arguing that he isn't a moral person who doesn't want us to live as one.

In Quantum Mechanics, some ideas can seem counter-intuitive. Some aspects of Socio-Economic theory can likewise seem counter-intuitive. I have no doubt Ethan knows all the pitfalls of the former, but is not nearly as bulletproof on the latter. I believe some of his proposed solutions will have consequences he didn't intend, and are ultimately a detriment. I'm open to being proven wrong, but so far I'm not getting back any substance.

One particular example was the sentiment expressed in his piece titled ‘The two questions that determine your scientific literacy’. It was essentially elitism.

Ah, more lying bullshit, denier. No, it was not, essentially or even tangentially "elitism".

Is it elitism to get a qualified medical doctor to diagnose your illness rather than your house maid?

2-The Literate(non-Scientists who worshiped group #1),

You really never tire of strawmanning, do you?

I believe some of his proposed solutions will have consequences he didn’t intend...

That's funny, because when you say he wants to do x y or z, or he thinks x y or z, you are very clearly attributing intent to him. If you think there are consequences he doesn't intend, then stop saying he supports those consequences.

If you're open to being proven wrong, then consider the fact that your position over time has become logically contradictory. You first started making claims that Ethan supported all these crazy outcomes. Overturn the first amendment! Criminalize speech! Now you claim he doesn't intend these detrimental consequences of his proposed solutions. Which is it?

And why is the answer isn't neither of those? Because we wouldn't want a false dichotomy to remain, would we. That would make any conclusion made unreliable at best, and deliberately false at worse!

For a while last year or the year before he was on a kick of protecting women.

telling. It's been apparent from your comments for some time that helping others is (to you) a sign of weakness, but to see you put it so blatantly is interesting. You really aren't much of a decent person are you?

@eric wrote:

Good lord, man! How you turn someone’s own sentence around so badly without feeling a sense of shame?

Perhaps you should ask Ethan if he believes there exists in our society 'marginalized but valuable voices' that need protections. Ask him if he thinks affirmative action is a positive. With what Ethan has written I'm very confident that he does. Before you go insisting I'm wrong, perhaps you should ask him.

Perhaps you should read what Ethan says, not what you claim he thinks, denier. Perhaps you need to connect your claims to what you're responding to, too.

And you pretend to have a wife who's a scientist... Sad.

"Perhaps you should ask Ethan if he believes there exists in our society ‘marginalized but valuable voices’ that need protections."

Yes, yes there are. That is an incredibly stupid question if it means you don't think there are.

"Ask him if he thinks affirmative action is a positive"

Again, yes it is.

Denier:

Perhaps you should ask Ethan if he believes there exists in our society ‘marginalized but valuable voices’ that need protections. Ask him if he thinks affirmative action is a positive.

Well, it appears we're getting to the crux of the matter. Ethan (and probably many other posters) think that protecting marginalized voices leads to a better planet and future for us all. Sort of a positive sum game. You, OTOH, do not think this. Would it be fair to say that you think protecting marginalized voices does not lead to a better planet or future for you? That you see this as a sort of zero sum game, where giving extra help to people who traditionally aren't listened to means Denier's voice must perforce be getting less respect or less air time?

eric wrote

Would it be fair to say that you think protecting marginalized voices does not lead to a better planet or future for you? That you see this as a sort of zero sum game, where giving extra help to people who traditionally aren’t listened to means Denier’s voice must perforce be getting less respect or less air time?

Yes to the first question and no to the second question. I believe a rising tide raises all boats. With your first question, the protection of marginalized voices is harmful to them and thereby harmful to me. I believe that Protectionism has been proven time and again to have long term negative effects. When you carve out segments and apply different rules to them, especially if the targeted segment can be easily identified, you’ll never get rid of the division and you’ll never get equality. Never. The only way to ‘live together as one’ is to get rid of the partitions and treat people as individuals.

@eric wrote:

Ethan (and probably many other posters) think that protecting marginalized voices leads to a better planet and future for us all.

I do agree with you that probably many posters here exhibit the soft bigotry of low expectation directed towards certain identity groups they see as marginalized, and their intrinsic inferiority requires society to bestow protections. I counter that the problem isn’t with the identity group, it is with the bigotry.

"exhibit the soft bigotry of low expectation directed towards certain identity groups they see as marginalized,"

Realizing people who are marginalized by scum like you can succeed when given a chance is bigotry? Wow. I hadn't realize just how evil libertarians could be until you began showing your true colors.

I believe that Protectionism has been proven time and again to have long term negative effects.

Time and again, eh? So you think the US would have been better off if the federal government had not forced the states to integrate their schools? I grant you the outcome has its own flaws, but I find it hard to think that our education system would, on net, be better if that had not happened. I think racial disparities in wealth and education would be a lot worse.

I also don't think these efforts always have to do with 'the soft bigotry of low expectations.' Some might, but for example tests using identical resumes with merely different names (male vs.female, or traditionally 'white' vs 'black'), show that most people are biased in favor of white males. Wanting to reduce or eliminate this bias has nothing - and could not possibly have anything - to do with lower expectations for women on minorities, because the resumes are identical. Down to the last period and same paper identical. What we want to do is eliminate the hard bigotry of higher expectations society often levies on non-white non-males for no rational or justifiable reason.

Is he regretting voting Trump now?

@#16,17.etc
With DSLRs, one can use IR means (modified filters) to record darker skies, then add in RGB for the color enhancement. Taking darks helps get rid of most 'hot pixels' from an extended recording session. The benefits are immense compared to the old days. Getting rid of surface scatter still needs to be overcome, though.
Invigorating, what?
:)

@Denier #30:

I believe a rising tide raises all boats.

That idea was behind tax cuts for the rich. Cut their taxes, they would spend more, leading to everyone benefiting. It didn't turn out that way.

[T]he protection of marginalized voices is harmful to them and thereby harmful to me.

This comment belongs in the "not even wrong" category. You overlook the obvious: why are these voices marginalized in the first place? Not by the choice of the marginalized groups. The fact that you can't (or won't) comprehend that that is why they need protection is astonishing, and not in a good way.

By Julian Frost (not verified) on 06 Feb 2017 #permalink

@eric wrote:

So you think the US would have been better off if the federal government had not forced the states to integrate their schools?

I think desegregation was imperative. Dividing people by race is wrong. Racial bigotry is harmful, and school integration was a necessary step but I believe the implementation was wrong. It should have been done by residency mixing or economic mixing via lottery. The government and every other public or private institution should have been forbidden from enacting any policies that address race, color, religion, gender, or national origin. (Orientation wasn’t included in the Civil Rights Act of 1964 but I have no problem with including it)

For at least 2 decades it would have been whistling past the graveyard. Everyone would have known it was about race but it wasn’t institutionalized that way. Instead they made it all about race and government led its institutionalism by example. That is fucked up and the affect it had on the racial wealth gap is about what you’d expect.

Stop dividing people. It doesn’t work. It isn’t a long term solution.

Let me ask you this: You seem to believe in dividing people up and treating different skin colors or ethnicities different. What is your end game? How do you get from marginalized group to task complete where we’re all living as one with one set of rules for everyone? Spell it out for me. How do you plan on getting from 'A' to 'B'?

@Denier #30:

I believe a rising tide raises all boats.

That idea was behind tax cuts for the rich. Cut their taxes, they would spend more, leading to everyone benefiting. It didn’t turn out that way.

But he doesn't want tide lifted for the underprivileged. Weird that.

But he hopes to be the wealthy and powerful one day, he doesn't want the ladder pulled up until AFTER he gets there.

Shorter denier: I don't like the end of segregation it I'll pretend I believe it was done the wrong way. If I make up something foolish I can slam the nasty government and pretend I don't mind baving yucky people living near me.

@dean

Same question is open to you. You were telling everyone in the other thread how you had more on the ball than I did. Let's see you put some of your amazing intellect to use.

After you've created a cultural subsidy to "help" a marginalized identity group, what is your endgame for completing the task of having society all living as one with one set of rules for everyone?

Strawman, denier. And presupposes an ideal not in evidence, but only placed on another.

You preen yourself with being better than everyone else, with the "right" ideology of "fuck the hindmost", you tell us what the endpoint of your ideology is.

It should have been done by residency mixing or economic mixing via lottery. The government and every other public or private institution should have been forbidden from enacting any policies that address race, color, religion, gender, or national origin.

Those two goals are practically impossible to achieve together, since historically and socially people have self-segregated. 'Residency mixing' without regard to race just leads back to segregated schools, for example via the 'white flight' in the 50s-70s. Now sure, in some hypothetical society that didn't start with geographically segregated neighborhoods and people were color blind when they chose where to live, your solution might have worked. But we don't live in that world. Because of our socio-historical baggage, racially blind regional mixing policies would simply (IMO, do simply) perpetuate racial disparities.

Stop dividing people. It doesn’t work. It isn’t a long term solution.

Not everything has to be. There isn't going to be one single, unified, elegant solution to discrimination in the US. We're going to have to kludge together a variety of disparate solutions, some focused on fixing short term problems and some focused on the long term.

Triage is not long-term care. Social problems likewise don't all have to be addressed through idealized long-term solutions.

How do you get from marginalized group to task complete where we’re all living as one with one set of rules for everyone? Spell it out for me. How do you plan on getting from ‘A’ to ‘B’?

I can't speak for everyone but my support for things like affirmative action, in broad strokes, goes like this:
1. We use AA-like measures to reduce the bias towards white males (etc.) in hiring, promotion, education, and so on. Again, not a bigotry of low expectations but a recognition that favoring that specific subset of the population when all factors are equal currently happens in the absence of social controls, is profoundly unfair, and thus we need social controls to stop it from happening.
2. This leads to more diverse work places and schools.
3. This in turn reduces biases amongst school- and work- goers, because they see and interact with people they generally otherwise wouldn't.
4. As the biases disappear, so too does the need for AA-like measures.
1-4 codicil: we also need to recognize that perfect should not be the enemy of good here. Its likely we won't be able to reduce all biases. That's okay. Its likely that constantly shifting biases might mean constantly updating our strategy. That's okay too. Just because a workable collection of solutions isn't a single elegant monolith is no reason to trashcan it. I think, Denier, you're looking for the single elegant monolithic solution. The social rule that will work now, later, and forevermore to bring about an equal-opportunity and just society. There isn't one (and, frankly, I would beware of anyone selling one). Even the founders recognized that; that's one of the reasons why the Constitution has an amendment process built in. Sometimes you fix the problem in front of you in an expedient manner, and work on a better long-term solution while you're doing that.

@eric wrote:

We use AA-like measures to reduce the bias towards white males (etc.) in hiring

I'm going to stop you there. You're wrong right out of the blocks but your example is instructive.

There is not a bias toward hiring males. It is actually the opposite. Women who are seeking jobs are currently finding them on average one week faster than their otherwise identical male counterparts. Academia is showing a 2:1 hiring bias toward women in STEM fields. In Tech, the bias is even greater with women being hired 238% faster than men. The January 2017 US unemployment rate for white men aged 20 and over is 5.0% while the unemployment rate for white women aged 20 and over is 4.5%.

I am fully aware of the landmark study using identical resumes with traditionally black vs traditionally white names. The labor statistics add further weight to the argument. Black men and women spend more time looking for a job than do white men and women. The unemployment rate for Black Americans is higher than for White Americans.

Your picture of the labor market used to be right, but it has since changed for women. The difference between Blacks and Women? Women are NOT legally a 'Protected Class' while African Americans are. With Black Americans they chose the way you want to go and with Women then did not. The result in outcomes could not be any more stark.

Subsidies strengthen the status quo. When you divide people out and provide aid as if they are a less able underclass, you turn them into a less able underclass. The initial need could very well be real but that doesn't mean you should cement it in place. If you want to help then help areas or economic classes. People can move out of areas and economic classes. They cannot move out of their skin color. When you make a skin color into an underclass you get what we have.

@eric

I do want to add one more thing: Even if I don't agree with the sentiment I do commend the thought you put into it and the civil tone. Thank you for that.

"I’m going to stop you there. You’re wrong right out of the blocks"

No he isn't.

Indeed there are many places where people openly admit that women are for babies and house cleaning.

"Women are NOT legally a ‘Protected Class’ while African Americans are. "

But women have rights for protection against sexism and harassment that black americans don't get unless they are women.

You're 100% shit scared that darkies are coming for your women, aren't you? Blazing Saddles wasn't parodying the merkins, it was a goddamned documentary.

At least we've gotten your heirachy of hate. Blacks, then women, then liberals.

I love that movie.

By Derek Freyberg (not verified) on 07 Feb 2017 #permalink

Denier:

Your picture of the labor market used to be right, but it has since changed for women.

LOL, that would imply that (or at least correlate with) AA-like measures have worked. If you're argument is 'they worked in the case of women, we've reached the goal, time to scale them back,' then we can debate that point. In fact we already have, and IIRC you somewhat inconsistently claim that while parity in undergraduate rates are a sign no such measures are needed, you simultaneously claim that the disparate rates of post graduate education aren't signs that such measures are needed. Parity is taken as evidence such measures aren't needed, while any disparity is dismissed as being caused by other factors. Is that about correct?

Citing such great strides forward in the employment and education of women over the last couple of decades, as evidence that pro-women measures over the last couple of decades didn't work and weren't necessary, seems just laughably wrong to me.

With Black Americans they chose the way you want to go and with Women then did not.

I would strongly disagree with that statement. Comparing any 30 year period between the end of the civil war and Brown to the 30 years after Brown, I think it's pretty clear that black communities were not "choosing" to be less well educated, rather they were in a vicious cycle actively supported by racist whites, and it took a court order requiring educational resources to be allocated more fairly to break that vicious cycle. You call such court orders a form of 'protectionism' and claim they never work. Well, it did work. I'm not claiming such regulations are a one size fits all solution or that they are appropriate for all social inequities, but I do claim it's a tool in our toolkit that we should pull out from time to time, when we think it's the best tool for the job.

Subsidies strengthen the status quo.

That depends on who you're subsidizing. If a group has a monopoly on some position or resource, and you subsidize them, they'll continue to maintain that monopoly. Remove all subsidies, and the monopoly may well continue under its own steam, because they can often be self-sustaining. Sometimes the best way to bring about true market competition is to break up the monopoly via (at least temporary) regulation or subsidize the little guy.

@eric

that would imply that (or at least correlate with) AA-like measures have worked.

If it worked, it would work for both groups. That isn't the case.

I'll end with this: In your proposed solution in post #41, Item #3 seems best summed up as 'changing the culture'. I completely agree with that statement. It is marketing and it can get you anywhere. I just don't believe that implementing institutionalized bigotry is the best way to go about it. In practice that method introduces statistical discrimination. If the marginalization gap does close, it will be despite Affirmative Action not because of it.

"If it worked, it would work for both groups."

Why? The one stealing all the food loses when we arrest them and incacerate, evict or kill the thief. Everyone else benefits, though, with less of their stuff being nicked.

And where is your proof it didn't? In case the idea is that we shouldn't stop thieves.

"There is not a bias toward hiring males"

Again, what an ass.

Affirmative action is seen by bigots as racism toward whites and by clowns as bigotry toward men, as attempts to level the playing field always are. The repeated foot-stomping done (by folks like denier, clueless of the actual facts) about deserving people (deserving being their code word for "people who aren't icky") reflect what they imagine the reality to be, not what the reality is.

Denier has shown he has no intention of discussing things based on facts but prefers the fact-free notion of "free market cures all" we hear so often. When the market actually fixes something it will make make the news, but that hasn't happened yet.

Denier:

If it worked, it would work for both groups. That isn’t the case.

Surely you're not claiming that all plans must work or none of them must work? Its entirely possible that one worked and the other didn't. The types of rules and practices we instituted for women vs. minorities are different, the percent of the population affected is different, the groups distribution of wealth, education, etc. is different, and so on. So is it really that surprising that the results weren't identical?

I’ll end with this: In your proposed solution in post #41, Item #3 seems best summed up as ‘changing the culture’.

I think when you see only X's being leaders, the natural inclination is to think X's make good leaders. This can cause a hirer to prefer X's to others, even to ignoring a non-X who is better 'on paper.' I think when you see more Y's become leaders, the natural inclination is to revise or modify that initial opinion so that now you think X's AND Y's can be good leaders, and your bias in hiring goes down. Note X and Y are not code here for men and women; I think the above argument is true for MANY sub-groups of people, including groupings by sex, age, race, religion.

I think "hiring-seeing-learning bias" can become a vicious cycle, and occasionally needs to be broken using formal rules or regulations that prevent the "prefer an X even though..." effect.

Do we call that preference "culture?" Am I wanting to change "culture"? I really hope not. It's certainly not part of my culture that women ought to be in the typing pool. Is it part of your culture that women ought to be nurses and men doctors? I'd like to think that these sorts of biases, while social in origin, are not an important part of our culture - and thus eliminating them is not a "cultural change" in any important way. That dispensing with racism and sexism causes about as much damage to our "culture" as dispensing with bell bottoms did. A part of our culture? Okay. An integral part of what makes us who we are, worth saving? No.

Ethan, “john” is deliberately misrepresenting your post on the limits of scientific investigation for rhetorical gain. He is completely clueless about science (since he doesn’t know what radiation is, nor what a geiger counter does), rabidly idiotic about logic (since he doesn’t know what a logical argument or premise IS, even after presenting some that were, as eric will attest, illogical and broken premises), and is not 100% convinced on a pointless blathering of bullshit and lies (and claims of lies) rather than deal with anything said if there’s some offtopic bullshit to chase after to “win” with.

Please kick the moronic son of a bitch off because they’re never going to allow themselves to visit actual rational discourse.

Ta.

"... what I see is someone who’s a minority in one way (he’s gay) bully and beat down people — in a public forum — who are minorities in ways he is not. Who are not part of his in-group ...'

One can see this type of behavior in many places.

Yup, you see it every time you look in the mirror and then insist it's your reflection's fault not yours.

Ethan,

As a judge ruled in 1863, "Res ipsa loquitur."

As someone smarter than you said in 2017, "So what?".