Wednesday, April 29, 2020

Space Age marvels - near and far

Let's lift our heads from Earthly troubles for a bit. First something cosmic -- BBC World Service uses me pretty often, most recently on a program about moving the Earth.   A light take on a very – um – heavy topic that I explicate further here.

Is “dark energy” real? It’s based on the notion that cosmic expansion started accelerating again, some 5 to 10 billion years ago, as apparently evidenced by the distance and brightness profiles of Type 1a supernovae, which are our standard candles for immense distances. But what if those candles were not “standard” across those billions of years? Might the brightness of a typical S1a have varied, as the galaxies got older, and more ‘metal-rich’? Or even (perhaps) as space-time itself got more stretched out? (I feel it, even across my almost seven decades!) 

If so, then the new inferred distance/recession curves might eliminate the supposed acceleration and thus any need for dark energy.  (There are other metrics like the Cosmic Background Radiation and the baryonic acoustic oscillations (BAO), but these are even more indirect.) What fascinating times. Fight for a brave, scientific civilization.

Soon the New Horizons spacecraft (with Pluto and and Ultima behind it) will take images of two "nearby" stars, Proxima Centauri and Wolf 359. When combined with Earth-based images made on the same dates, the result will be a record-setting parallax measurement yielding 3D images of these stars appearing (as points) to pop out of their backgrounds, giving very precise distance measurements.

Image from Inouye Solar Telescope
And coincidental with our re-release of my first novel - Sundiver… the new Inouye Solar Telescope based on Maui in Hawaii is taking the most detailed images of our Sun to date. Amazing pics of convection cells the size of Texas coupled with titanic magnetic fields and sources of the Solar Wind that sometimes surges as massive storms.  

== ...and only slightly less cosmic ==

On a broader scale,  a study published in The Astrophysical Journal  found that hundreds of galaxies were rotating in sync with the motions of galaxies that were tens of millions of light years away. It should be impossible that the galaxies separated by six megaparsecs [roughly 20 million light years] directly interact with each other. Perhaps the synchronized galaxies may be embedded along the same large-scale structure. “In 2014, a team observed curious alignments of supermassive black holes at the cores of quasars, which are ancient ultra-luminous galaxies, that stretch across billions of light years.” And yes, one notion is that this provides forther evidence for “we’re in a simulation.” Well, it’s one thought occurring to science fiction readers.

Amazing composite image of the Tycho Supernova, with the red and blue coloring used to give a 3D feel to it (retreating and advancing silicon and other stuff too).

While breathless reporters ask if Betelgeuse is about to go supernova (not huge odds in our lifetimes) a smaller spectacle seems assured in mere decades. V Sagittae is made up of an ordinary star orbiting around a white dwarf star, with the former’s matter slowly falling onto the latter. The astronomers’ mathematical model predicts this process to result in a merger between 2067 and 2099. “It’ll be “substantially brighter than the all-time brightest known nova just over a century ago, and the last time any ‘guest star’ appeared brighter was Kepler’s Supernova in the year 1604.”

China has finally booted up its “super-Arecibo” radio telescope. The completed FAST is about 2.5 times as sensitive as any other radio telescope on the planet, and is expected to have four times the range of the next largest dish. That is, till the Square Kilometer Array goes live.

Astronomers have discovered a 'void' with absolutely nothing in it. ‘The void, which is about 6 billion to 10 billion light years away, is nearly a billion light years across, is empty of both normal matter and dark matter. The finding challenges theories of large-scale structure formation in the universe.’

Speaking of which, here’s the coolest recent thing: a light echo of SN 1987A! Some of the light from the supernova from 1987 went a different direction, bounced off a gas cloud and got here almost 33 years late. Even cooler, we can do this proactively. We can calculate and find gas clouds that WILL reflect a known event to us, at some future time, and then catch some of the very earliest light curves from sudden events like supernovas. 

== And more coolstuff! ==

The first-ever direct image of a black hole's event horizon was a truly impressive feat though so-far low-resolution, confirming exactly the visual appearance (of an accreting singularity) predicted by Caltech Nobelist (and sci fi fan) Kip Thorne, for the movie “Interstellar.” This computer simulation is truly gorgeous. You’ll be glad you clicked.

A titanic, expanding beam of energy sprang from close to the supermassive black hole in the centre of the Milky Way just 3.5 million years ago, sending a cone-shaped burst of radiation through both poles of the Galaxy and out into deep space.

Hubble Spots a Ghoulish 'Face' in the Depths of Space. Well, two galaxies colliding. But kewl. Watch as it happens! (Be patient.)

The fastest eclipsing white dwarf binary yet known orbits in only 6.91 minutes, and is expected to be one of the strongest sources of gravitational waves detectable with LISA, the future space-based gravitational wave detector. “Closely orbiting white dwarfs are predicted to spiral together closer and faster, as the system loses energy by emitting gravitational waves. J1539’s orbit is so tight that its orbital period is predicted to become measurably shorter after only a few years.”

==The Sci Fi Beat ==

 Kickstarter for SHAPERS OF WORLDS, an anthology featuring first-year guests of The Worldshapers podcast, offers stories by Seanan McGuire, David Weber, me, and many others. 


TCB said...

JPL released an animation of a massive black hole orbiting another, and sending out periodic very very bright flashes of light as the smaller one smashes through the accretion disk of the larger. From the timing of the flashes they worked out the orbit.

Two massive black holes are locked in a dance at the center of the OJ 287 galaxy. The larger black hole is surrounded by disk of gas; it is also orbited by a smaller black hole that collides with the disk, producing a flare brighter than 1 trillion stars. But because the system's complex physics affects the smaller black hole's orbit, the flares occur irregularly. Scientists used NASA's Spitzer Space Telescope to detect one of these bright flashes on July 31, 2019, confirming that they can now anticipate the timing of these flares to within four hours using a detailed model of the system.

In the second half of the video, the animated diagram on the left illustrates the orbit of the smaller black hole (the red dot) around the larger black hole (the stationary white dot) and its collisions with the disk of gas (the pink line), which occur twice per orbit. The years of the collisions are indicated below the diagram and in the graphic on the right shows, dating to 1886.

David Brin said...

TCB Incroyable!

scidata said...

I've been trolled a bit over that black hole simulation. People say it's just another fake news animation. I provide links to show the science behind the simulation (and Kip Thorne, and even "Interstellar"), but that only opens me up to 'elitist' taunts. The stupid, it burns. 'Fake news' is an excuse for just being too damned lazy to read or think.

David Brin said...

Tell them that we all were raised by Hollywood to reflexively oppose some "authoritarian elite." They choose to let themselves get talked into hating all smart people, scientists, doctors, teachers, journalists and the "deep state" men and women who saved us from Hitler, Stalin and bin Laden. Fine, their (stupid) decision. The elites WE loathe are tyrants, commie dictators, mafiasm gambling moguls, Wall Street connivers and inheritance brats... the folks paying for the p;ropaganda behind the War on Science and all fact people. Our hatred of oligarchs is backed up by 6000 years of oppression by kings, priests and feudal lords and plantation slave-owner. Theirs is backed up by... hatred of nerds who refused to be bullied and built great companies and lives. Nerds who these ingrates owe everything to.

But fair enough. Go hate nerds. Only... are you men? Seriously, have you balls? Any at all? Because a man with cojones would be willing to put MONEY BETS on his hot air screams -- e.g. that climate change is a hoax, or any Clinton mania slander, or any randomly chosen lie from Trump's list of 20,000.

Hate science? Fine. Live by your creed and refuse the benefits of anything we invented in the last 70 years.

Kevin Brinck said...

Hey Dr. Brin, I saw the Ancient Ones was available as a new novel / novella / your choice option. Does it have significant expansion from the story, and plot resolution from the chapters you originally posted on Baen's Universe?

Because honestly I felt cheated when the promised mind-splatting who-would-have-ever-guessed that reveal in Existence (Spoiler: it's a viral email) hadn't been explicitly described as such in the pre-published stories on Baen's Universe.

But Existence was worth the Baen's Universe + Lungfish things you added onto it but...

You've promised a new, novel sequel to Kiln People. Some people detest puns, but I don't mind them in the service of the story.

Smurphs said...

RE: Re-release of Sundiver:

I picked it up recently with the Kindle deal and re-read it for the first time in 30 years. I only remembered the broadest outlines of the story. I was not surprised at how good it was, nice. job! I was surprised at how many clues I missed the first time around. Again, nice job!

BTW, as my physical library is long gone (donated, given away, or just recycled), these $5 Kindle deals are great. Keep 'em coming.

scidata said...

Frank Ramsey was a classic example of individual potential. Mathematical psychohistory might have once had an 'inverse Mule'.

And trolls calling me an 'elite' is laughable. I'm a farm boy who wandered into libraries because there was little else to do or hope for (a fairly common story actually). But how many Ramseys (or Hypatias, Moseleys, Turings) have been cut short by fate or plowed under by fascist bullies? Nature's quest for diversity is what shaped us from a blob of goo. Tolerance is a very small price to pay if it gets us to the stars.

This is why the stupifying drumbeat of numbers of infections and deaths horrifies me almost as much as the 'liar tweets tonight' does. It paves over individual potential.

Keith Halperin said...

@ Everybody: Re Poll-


@ Dr. Brin: Re: New Solar Image-
Well, I knew the moon was made of green cheese, but now I know the sun ( is made of Tahini granola (


@ Dr. Brin and Everybody: Re: Fun and Silliness-
Dr. Brin, can't remember if you said you were doing more Uplift stuff or not. (Hope so...)
Anyway, if you ARE, here's an idea- you create a contest for the names of new races and you pick the ones you like, crediting the winners in the book.

Meanwhile, the names of a new faction and a few races:
The Fabricator Faction-
They believe all other factions tell lies about the Progenitors.
A major race of this greatly-despised faction is the Tarrumph (a Tarrumph -ab Narcis -ab Le'er -ab Krimnall -ul Vank'uhh) closely aligned with Mak-Koh-Nul and the P'uH T!en (designations unknown). Besides this basic disbelief in- and disrespect for the values of any other faction, they seem to have few if any other core beliefs beyond a belief in their own innate superiority and a desire for power and wealth within the Five Galaxies.
The Tarrumph are regarded as both bullies and cowards, the Mak-Koh-Nul as obstructionists and tradition-breakers, and the P'uH T!en as greatly manipulative toward other races. Approximately 12,000 hab-years ago, the Fabricators attempted to form an alliance with the Thennanin
(a-Thennanin ab-Wortl ab-Kosh ab-Rosh ab-Tothtoon ul-Paimin ul-Rammin ul-Ynnin ul-Olumimin) and the Oo'tAh (designation unknown) of the Abdicator Faction, feigning commonality of interests, but neither race was persuaded, and to this day both races regard the Fabricator races with loathing....

SW, All

Larry Hart said...


Frank Ramsey was a classic example of individual potential. Mathematical psychohistory might have once had an 'inverse Mule'.

I'm not sure what you're getting at with 'inverse Mule'. I haven't read the entire article yet, but so far he sounds like a real life Ebling Mis.

David Brin said...

scidata, fun riff on the Fabricatr faction! Hoping by the time I resume work on Escape From Kithrup all the jokes will be about gone-obsolete figures.

You guyys are being erudite today. Ebling Mis-sed my breakfast, already!

Keith it was only the first maybe 4 chapters of Ancient Ones that appeared in Baen's Universe... so lots of wretched puns to go! But Lungfish fit so well into the theme of interstellar parasitism that it called out for inclusion in EXISTENCE.

 Ashley said...

What do you make of MOND and superfluidity as an alternative solution not requiring WIMPs and Dark Matter?

jim said...

Well this “lazy, useless, ingrate, ass without a conscience*” just finished talking with the director of research and development (at my essential workplace, doing my essential job) and I have convinced him to initiate a crash R and D project to develop reliable, inexpensive stickers that will change color if you have a fever. Put them on your forehead and if it is green you don’t have a fever if it is red you do. We are pretty sure we can do it, not sure how quickly we could scale up yet. This goes along with our other crash R and D project – anti -viral top coat for packaging ink.

David Brin said...

Ashley While the failure to find viable dark matter candidates is certainly bizarre and intriguing, MOND demands something even weirder, a variable Newton's Law of Gravity. I'm gonna have to stay skeptical about that... though it's kind of reminiscent of Vernor Vinge's "galactic zones" big idea in his novels. Brilliant stuff there.

Actually, I have a completely different alternative... that gravity is the weakest force because much of it bleeds out laterally to other dimensions while EM and strong and weak forces remain confined to our Einsteinian four. If so, then that effect migh ebb with distance from major mass concentrations like the galactic core and at distance allow something slightly stronger than inverse square.

But then I am more a sci fi guy than a (fully licensed) physicist.

Keith Halperin said...

@ Dr. Brin: Re: Who said what:
I did the talk on the new faction.
Scidata, Larry talked about "Inverse Mule".
Kevin talked about "The Ancient Ones".

Mule musings:
1) ISTM there were few fen, cons, or blogs on Gaia. If there were- the Mule would probably have been a happier, less-isolated person. Perhaps he is a distant descendant of Locum Ranch.
2) With his mentalics and visisonor talents, Mulie could have been a successful musician, comedian, monologist, or performance artist- a Ric Ocasek/Steve Martin/Spalding Grey/Josh Kornbluth/Bill Irwin-type.
3) Mulie was short-sided- he could only convert so many people, but using what WE know npw, he could have combined mentalics and other techniques to create a self-sustaining movement or cult not dependent on him: "Make the Galaxy Great Again!"...
4) If they'd been in the novels at the time, Mulie could have learned about those mentalic generator/curiosity suppressors around the worlds of the Galaxy, and had someone hack them to aid his conquest.
5) Gaia (who even knows what the moss and rocks think about) should have recognized Mulie as "one bad muthfucka". Why didn't She "go downright mentalic on his ass" and "fix" him? (Maybe he was part of HER plan!)


David Brin said...

Okay then jim. Yay at you. See the main character of my story "The Giving Plague." A self-confessed cynical ass who (he grudgingly admits) has done tremendously more good than harm for the world.

Like Benedict Arnold, a conceited jerk who saved the Revolution three, maybe four times and proved really bad at treason.

So yay at you. Keep coming back here and muttering, if it keeps you going.

Smurphs said...

jim, good luck on your project. But be sure to do your due diligence. Contact thermometer stickers are not a new idea. My fish tank has them. But, to my knowledge, they are not very accurate/precise. But maybe precise enough.

sociotard said...

The US patent office has ruled that AIs cannot be listed as inventors.

Alfred Differ said...


Make it a headband and we can revive a version of mood rings. 8)

Next to return... bell bottom jeans! Loved those!

A.F. Rey said...

I have convinced him to initiate a crash R and D project to develop reliable, inexpensive stickers that will change color if you have a fever. Put them on your forehead and if it is green you don’t have a fever if it is red you do.

But how will you know it is really a fever, and not just the result of listening to Trump's latest press conference? ;)

jim said...

The color change technology is not new and it comes in a few varieties but the basic mechanism is this:
You have a dye that is one color in a liquid matrix and a different color in a solid matrix.
The older (cheaper) version uses a wax with a well defined melt point, but these are not accurate enough. There are different matrix that have a much more precisely defined phase change, the plan is to use them. But the supply chain for these raw materials is quite different from the wax supply chain.

This project is pretty strait forward, with well defined qc parameters, it is really 99.9999% development not a lot of research.
We really only need to develop one very precise color change colorant. Turning the colorant into an ink and printing it is no problem.

I have no idea what the final sticker would look like. If it was up to me, I would keep it simple like a dot or a triangle the marketing people will probably have different ideas.

David Brin said...

While it is grating to be lectured by the PRC, this short cartoon & tweet summarizes concisely and accurately the situation the Foxite-Putinist-Trumpists have put us in. Led by idiots (or worse) we no longer lead the world. (The aim all along.)

Keith Halperin said...

Re: Dr. Brin & Everybody: Fen Alert-
According to,
244 BxY (2006 CE):
Earth based observers discover NuDawn orbiting in the habitable zone.
Using my incredible research powers (,
I learned *HD_69830_d was discovered in 2006 and orbits in the habitable zone of its star, which is about 41 ly from here.
It's a "warm Neptune," of 18.1 M⊕ so a moon as proportionately as massive as Luna would be about 2x the mass of Mars...

Meanwhile Dr. Brin, you have about 5 years to get us a near-light drive for probes:
225 BxY (2025 CE):
Near light speed probes sent to six planets orbiting stars.
All planets are in the habitable zone and show evidence of water and O2.


Keith "Should Use My Time Wore Wisely" Halperin

*Somebody probably let you know this 14 years ago...

 Ashley said...

With David's kind approval here's a couple of links for those interested in an alternative explanation of Dark Matter from Sabine Hossenfelder's blog (Physicist) talking about MOND and superfluidity.

And a YouTube presentation by her on the subject:

scidata said...

S. Hossenfelder: "we have a lot of observational evidence that we are misunderstanding something"
The beauty of math and logic gets SHUT DOWN.
I feel a SETI bru-ha-ha coming on :)

Ahcuah said...

And in other news, the cheaters (anti-flat, -fair, etc.) are fighting back. They are threatening to take their money and go home if Elizabeth Warren is the VP pick.

'Anyone But Elizabeth': With Bernie Out, Big-Dollar Biden Donors Aim to Nix Warren as VP Choice

This is despite the latest polling that shows that Democratic voters preferred a Biden/Warren ticket.

A German Nurse said...

@sociotard: Interesting piece that one day could be used as a precedence, when the legal question arises if a self-aware AI should be granted full citizen's rights or to be considered the property of their creator.

Alfred Differ said...


Thank you. I appreciate stuff like that.

I'm an admitted skeptic of any gravitation theory that doesn't have inertial and gravitation mass equivalence built in from the bottom, but there is more than one way to do that. One can also punt the issue in a few different directions too. Empirical fixes are rarely among any of these options, but they help temporarily by showing approximation terms that we can expand for in the other theories.

My professor's preference was to treat an objects momentum 4-vector as its gravitational 'charge'. In the limit of low speeds, it is Newtonian. At higher speeds it picks up terms that look 'magnetic', but velocity dependence isn't acceleration dependence, so I don't see a MOND connection.

The inverse distance squared term in Newtonian gravity is really just a statement that the universe (as we know it) is 4-D. It's a symmetry thing. One implies the other.

Anonymous said...

@ Dr. Brin & Everybody: Re: Content vs. Discussion Disconnect?

I enjoy the postings re new science developments (Type Ia supernova in [hopefully] my lifetime? YAY!!!} ATST, much of what we discuss here is how to make the world better (from our perspectives) socially, politically, and/or economically. However, there seems to be very little posting on research updates in any of these fields, at least from what I've seen in my relatively short time here. I'd enjoy seeing postings/links on the latest relevant papers in behavioral economics, cognitive neuroscience, political science, etc. to enlighten and enliven us.

I'll start with these Wikipedia articles on what the "best" ways are to select a single candidate from among many (SPOILER ALERT: it's not our usual "First Past The Post, Winner-Take- All" method):,

A final note, Dr. Brin: there is a highly respected political scientist named Arend Lijphart (,,, who is Research Professor Emeritus of Political Science at the University of California, San Diego., presumably relatively close to you.
Perhaps you could send him a copy of "Polemical Judo" and ask his opinion...



David Brin said...

Thanks Keith.
As for Covid rumors, I'm willing to try things that are cheap and proved safe and reasonable "it can't hurt." Here are a couple.

Some papers emphasize Vitamin D.

John Cramer suggests you take 22 mg of Zinc Picolinate and 475 mg of Quercetin (a zinc uptake enhancer). Zinc has long been touted vs. colds, many of which are corona viruses... but uneven results may be due to poor uptake into cells.

Thoughts? Is Tim/Tacitus still with us? Catfish n' Cod?

Tacitus said...

Yes, I'm still around. I hop in when I have something to offer.

I'm a bit negative on the zinc question. Benefits? Debatable. Side effects? Anecdotally I have a friend who swore by the stuff and loaded up to prevent or treat colds. Ended up with total loss of taste and smell.

Mark me skeptical. Of course I'd take bigger risks for more serious maladies.


David Brin said...

And the dosages I mention don't sound dangerous or 'loaded up".

duncan cairncross said...

Hi keith your ranked pairs link leads to a dead end - can you have a look and see what went wrong?

Anonymous said...

Apologies, Duncan and folks:
Not sure why this didn't work.

This one doesn't have the chart (that you can also see in the Schulze Method):

AVR said...

Dr Brin, which anthology did you contribute to? Neither the kickstarter page linked nor any of the three anthologies' pages on Amazon credit you.

David Brin said...

Oh I'm not in that one. What, you think I ONLY self-promote? ;-)

AVR said...

So who's the 'me' in 'offers stories by Seanan McGuire, David Weber, me, and many others.' then?

yana said...

Ashley thought:

"MOND and superfluidity"

scidata thought:

"The beauty of math and logic gets SHUT DOWN. I feel a SETI bru-ha-ha coming on :)"

Heheh, it all connects, doesn't it? You don't need to ghosthunt dark matter or energy, if the fine structure constant is not actually, perfectly, constant. It was the splinter under the fingernails of both Fermi and Feynman. If alpha is rising, then you already "have inertial and gravitation mass equivalence built in from the bottom," it rolls Newton and Einstein into play-doh snakes eating each other's tails.

David Brin relayed:

"Vitamin D ... Zinc Picolinate ... Quercetin"

Tim Wolter thought:

"Mark me skeptical."

Me too. One conspiracy nut preached to me at length last week about hyper-dosage of vitamin C (paging Doctor Pauling, call for Dr. Pauling). Another homeopathic adherent swears that vitamin E is the key to beating the 'rona. One of the more virulent conspiracy nuts i know has it all figgered out: Vitamins A & D. When i suggested Vitamin B-12 because studies show that if you take a lot of that one, you talk to god and god talks back, he looked at me askance, as if I was the nutty one! :-)

All such seriousness aside, skip the supplements. Just get the vitamins you need from eating things which are too slow to run away. I have a particular need for vitamin D, so did a buttload of research a few years ago. Then i built a machine which quadruples the D content of a common food. Cost about $85 in parts and a couple hours at the workbench. I love it and my Dr. is amazed.

TCB said...

I haven't done this in a while, but I've used the following combo for helping my immune function during colds: Cold-Eze lozenges for the zinc, lots of vitamin C and D, and astragalus (an herb that is claimed to have the same efficacy as echinacea but in my opinion is a bit more effective). My totally unscientific and anecdotal experience is that the cold is notably shorter and milder about half the time when I do the combo. (It's probably been a different cold strain every time anyway, though, and that alone could skew results.)

On a personal note, my mother in law died from COVID today. She was 97 and had been declining for a few years; she may not even have known what was happening. Her nursing home in Massachusetts has now lost 7 residents and I assume that will soon double.

Anonymous said...

Apologies, Duncan and folks:
Not sure why this didn't work.

This one doesn't have the chart (that you can also see in the Schulze Method):

Keith Halperin said...

@ Dr. Brin: Re: "What, you think I ONLY self-promote?"-
To paraphrase an earlier author:
"If I do not promote my books, who will promote for me?
If I do not promote others, what am I?
And if not now, when?"


Larry Hart said...

Keith Halperin:
Not sure why this didn't work.

It DOES work.
You included a comma at the end of the address the first time, which is why that one didn't work.

David Brin said...

TCB condolences and hoping grandma was at peace.
AVR I will look again at that anthology. Some of my postings contain riffs that were inserted a month or more earlier in a topic compilation. Forgetfulness can slip in!

Thing about supplements is that "can't hurt" requires judgement. Example. A heavily, many times, diluted homeopathy tincture is pure water, though they call it "very strong." One that's been diluted just a couple of times is "weak" and thus contains a lot of whatever poison it is. Seriously.

I'm doing vitamins at no more than double normal because much more is both expensive and dances toward red lines in some cases. Heck, I already eat monkey-loads of fruit & carrots. But I will try the zinc and uptake thing. WTH.

scidata said...

Ope, Feynman got mentioned. Another chance to mention computation.
Computation is to physics what literature is to thought. It's a sort of 'pre-cognition' or 'co-cognition'. It has its own strange form of intelligence that's, well, artificial. Here Stephen Wolfram uses computation to explain, surprisingly, the genius of Richard Feynman.

A German Nurse said...

@TCB: My condolences.

@Food: Overdosing with hydrophile Vitamins (B-Series except B12 and C) is unproblematic Dinge any excess uptake is stored. Lipophile Vitamins (A, D, K) need a minimum of fats to be effective, and cause hypervitaminosis if consumed in excess.

Echinacea is most useful when used before or during the early stage of a Cold. It may or not may affect the infection risk with the coronavirus, did not found any reliable sources.

Zinc is generally not needed if you have a healthy and varied diet (and I wage a secret guerilla war against using zinc salves in wound treatment.)

For self-therapy of colds, I used Chicken soups, hot milk with 1-2 teaspoons of (natural!) honey, and a day off work or two (if you can afford it).

David Brin said...