# SCIENCE ERRORS

Here are scientific errors I found in the book "Dune" by Frank Herbert:

1. The instruction by the Guild: "No flights over the forbidden areas of Dune." is impossible to obey except by not orbiting Arrakis.
• Every orbit around any object in space is an ellipse with one focus at the center of mass of the object.
• Every orbit around a planet must cross or follow its equator.
• There is no possible way that an orbiting ship could stay over the populated northern regions.
• The massed armada of ships could not possibly stay in space over Arrakeen. It must either orbit the planet or expend a huge amount of energy to stay over Arrakeen.

2. The moons of Arrakis cannot possibly have the behavior the book describes.
EVENTPERIODEARTH EQV
Sun rises and then sets0.5 day12 h
Dark0.025 day36 m
Moon #1 rises and then sets0.2 day4h 48m
Dark0.05 day1 h 12 m
Moon #2 rises and then sets0.2 day4 h 48 m
Dark0.025 day36 m
• The book describes the sun and two moons being up separately with dark periods in between
(Example timings at right).
• This is portrayed to occur everywhere on Arrakis.
• Note that, according to the map in the book, Arrakeen and Cave of Birds are on opposite sides of the planet.
• This means that it is night at Cave of Birds when it is day in Arrakeen.
• The moons are obviously in LaGrangian gravitational relationship in a common orbit.
• The most stable LaGgrangian relationship is an equilateral triangle between the planet center and the centers of the moons.
• There is no possible arrangement of moon orbits that can make this sequence appear everywhere on Arrakis.
• Moons orbiting Arrakis at twice the rotation rate could make this happen over only a narrow range of longitudes.
• Moons orbiting twice a day would appear in different orders and times on other parts of the planet.
• It is impossible for the sun and two moons to each be up at separate times with dark periods in between them.
• The only way such a sequence can occur is with an Atrrakicentric system.
(This means the sun and moons orbit Arrakis.)

3. Duke Leto says to have all of their timepieces are adjusted for Arrakeen local.
Herbert thinks all planets have the same length of day.
• Each planet has a different period to revolve around its sun.
• Thus, each planet has a different length of its year.
• Each planet has a different axial rotation period.
• Thus, each planet has a different length of its day/night cycle.
• Their "years standard" is a period as though on the parent planet (e.g. Earth).
• A very special timepiece would be needed to be set for different lengths of year and day.

4. For maximum illumination for vision, the Fremen tune all of the glowglobes to yellow.
• Assuming tuning glowglobes is like tuning LASERs, that gives essentially monochromatic vision.
• For full color vision, glowglobes should be tuned to red, green, and blue.
• Paul describes blue fabrics under this yellow light. That should be impossible.

5. The Fremen save up water so they can "change the face of Arrakis." Can this work?
• Doesn't this make the existing water shortage on Arrakis worse?
• Are they expecting the environment to somehow replenish the water?
• Is a source of hydrogen present in the interim to combine with oxygen to replace the water?

6. Mathematical Reality - Why do Fremen have people calling the time?
• Not very accurate in a large seitch.
• Dispatching a cielago (bat) with a time signal is just as inaccurate.

7. Mathematical Reality - Units of Measure - Herbert does not understand the Metric System.
• The Metric System usually has only ONE unit of measure for each kind of measurement.
• Each unit of measure can be prefixed by any of the metric prefixes (see table below):
Bigger: deca, hecto, kilo, mega, giga, tera, peta, exa, zetta, yotta
Smaller: deci, centi, milli, micro, nano, pico, femto, atto, zepto, yocto
• Herbert mixes liters with "drachms".
Using a second unit of measure defeats the purpose of the metric system.
• A drachm on Earth is a unit of money.
• Herbert uses a prefixed unit as a new unit and then uses large numbers of the new unit. e.g.
"Millions of Decaliters." (correct term: Megaliters)
"620,000 Solaris per Decagram."
• Multiple pointers would be needed on the flowmeter to read out 33 Liters 7 3/32 drachms.
The book says it has a single hand.

8. Mathematical Reality - Herbert does not know that both long scale and short scale numbering systems exist on earth.
VALUE LONG SCALE SHORT SCALE  RECIPROCAL
Metric
prefix
Power
of 10
Z = # of
zeros
Numbername
Z = 6 N
N name
Z = 3 N + 3
N Metric
prefix
Power
of 10
-10^001 (none)0(none)0-10^0
kilo K10^331,000 Thousand.Thousand.milli m10^-3
mega M10^661,000,000 Million1Million1micro μ10^-6
giga G10^991,000,000,000 Milliard.Billion2nano n10^-9
tera T10^12121,000,000,000,000 Billion2Trillion3pico p10^-12
peta P10^15151,000,000,000,000,000 Billiard.Quadrillion4femto f10^-15
exa E10^18181,000,000,000,000,000,000 Trillion3Quintillion5atto a10^-18
zetta Z10^21211,000,000,000,000,000,000,000 Trilliard.Sextillion6zepto z10^-21
yotta Y10^24241,000,000,000,000,000,000,000,000 Quadrillion4Septillion7yocto y10^-24

about long scale or short scale

Each country chooses their numbering system (right):

• The long-scale billion is 1012 = 1,000,000,000,000 = Tera.
• The short-scale billion is 109 = 1,000,000,000 = Giga.
• Some countries do not use base 10. These scales do not apply to them.

Herbert throws out "billion" as though it has only one value.

So we don't know if the 10 billion Solaris per 330 Standard Days is long or short scale.

EU uses the long scale. US uses the short scale.

In Canada, all provinces use short scale except French-speaking Quebec (long scale).

N is the number implied by the major name (mil = 1, bil = 2, tril = 3, etc).

9. Mathematical Reality - Herbert does not check the math of his numbers to check story accuracy.
• The figures in the story don't fit together:
Look what happens when we do the math on the Spice Melange market
1. Using the Short Scale:
• Income is 10⋅109 Sol / 330 day-std = 10 GSol / 330 day-std
• Melange price is 620000 Sol / Dkg = 62 KSol / g
• Melange sales is 10 GSol / (62 kSol / g) = 161 Kg (not even a Tonne - metric ton)
• Assuming the 10 GSol is a 10 percent profit instead of gross income:
Sales is 100 GSol / (62 kSol / g) = 1.61 Mg (Under 2 Tonnes)
You could put it in a pickup truck.
The entire 60 year repayment amount of spice would fit in two silos.
2. Using the Long Scale:
• Income is 10⋅1012 Sol / 330 day-std = 10 Tsol / 330 day-std
• Melange price is 620000 Sol / Dkg = 62 KSol / g
• Melange sales is 10 TSol / (62 kSol / g) = 161 Mg = 161 Tonne (~4 truckloads)
• Assuming the 10 TSol is a 10 percent profit instead of gross income:
Sales is 100 TSol / (62 kSol / g) = 1.61 Gg = 1.61 KTonne (~32 truckloads)
You could put it all in a one silo and send yearly production out on one ship.

If that's their total yearly production, why do they need many spice silos?
Jessica saw from the conservatory window at least 20 storage yards with spice silos.
Why so many shipments of spice?
Herbert needed either a much lower price or a much higher yearly profit.

• One possibility is that the spice has a low density, and takes up space with little mass.
- An 11 m diameter silo holds 1900 m3 of material.
- Assuming 200 silos, they have a capacity of 380,000 m3.
- Cinnamon has density of 446 Kg / m3.
- 1.61 Gg (see above, long scale) of cinnamon takes up space of 3610 m3.
(1.61 Gg / (446 Kg / m3) = 3610 m3)
- The cinnamon fits in one silo.
- The density of air is 1.29 Kg / m3.
- Assume that refined spice melange has a low density of 30 Kg / m3.
- 1.61 Gg of spice melange takes up space of 53667 m3.
(1.61 Gg / (30 Kg / m3) = 53667 m3)
- The spice fits in 29 silos.

10. How big was the selamlik (the Emperor's audience chamber) within the hutment?
Here are the known facts:
• The hutment has a 1000-meter diameter (500 m radius).
• The Emperor's starship lighter was the centerpost of the hutment.
• The selamlik is an oval (probably really an ellipse).
• The oval could be aligned with either the long axis or the short axis along the radius.
• A 40 m section of the hutment was blasted away, leaving the doors at the far end of the selamlik open to the sand.
• The fact that the "far end" was where part of the hutment was blasted away indicates the long axis is along the radius.
• So the long axis of the selamlik a = 500 m - 40 m - r (where r is the radius of the ship).
• The emperor was standing within his ship and seeing most of his entourage. This implies a large diameter ship.
• For 100 people, the minimum radius of the space is r = 4.21 m.
• Ignoring thickness of the walls, the selamlik is at most 455 m.

# LOGIC ERRORS

11. How do they have or know about all of these things from Earth?
• April
• Coffee
• Pansies
• Daisies
• Flies
• Cats
• Cinnamon
• Hell
• Saint
• Byzantium
• Now-disused second-person familiar case (Thou, Thee, Thy, and -th verb endings)

Environmentalists would go berserk if someone moved a species from one planet to another.

12. Alia was captured leading a band of Fremen and taken to the emperor. She was wearing an aba, a stillsuit, and sandals in the selamlik.
• When and how did she remove her stillsuit boots and put on sandals?
• Where did she get sandals?
• Did she then go out of the emperor's hutment in sandals (instead of stillsuit boots) to mark the dead for water recovery?

13. Two of the major schools formed after the Butlerian Jihad have survived: the Bene Gesserit and the Spacing Guild.
- What about the Mentat school and the Suk school?
14. The Bene Gesserit test to separate humans from animals.
- Is the Baron Harkonnen a human???
15. The Baron expected the Duke to refer to him as "Cher Cousin".
- Where does he come up with this? He does not know they are related.
16. Jessica was told to bear only daughters. Does that mean abortions for male offspring?
17. "Muad'Dib (the mouse) makes his own water." Condensing water is not making it.
18. Electronic sparking for communications?
• The invention of amplifying electronics ended the need for spark gaps.
• The neck pendant transmitters are obviously not spark gap.

19. How did a radio signal "Trapped in a cave." get out of the cave?
- Most radio waves can't pass through earth or water.
20. "We mustn't have an odd number." (of guests at the table)
- Why? Superstition? Male-female pairs?
21. Why didn't Paul ask Jamis, "Wouldn't you rather that I teach you how I did it?"
- "We promised Stilgar that we would teach all Fremen the Weirding Way."
- Jamis was unconscious when Stilgar explained the weirding way to the troop.
22. How did Hawat's crew open the palm lock to inspect the climate conservatory?
23. "The nightly prayer of parting"
• Fremen normally sleep during the day and are awake at night, to avoid the heat of day.
• For some events (e.g. sandrider test) they turn time around and are awake during the day.
• Is this nightly prayer originally based on being awake days or awake nights?
• Is it at the beginning of night or the end of night?

24. Who fights wars with knives?
- It's the only effective way to fight with shields.
25. How do smugglers have a factory crawler, ornithopters, and a carryall?
26. How do they "fix" a crysknife?
• An unfixed knife disintegrates away from flesh.
• Why didn't the Harkonnens or Sardaukar find Jessica's crysknife?
- It should have been on her body or in her room.
- What happened to it?

27. All of the Emperor's entourage watched Feyd Rautha fight Paul and saw Paul's crysknife.
• Fremen law: "Anyone who has seen a crysknife must be cleansed or slain."
• Must everyone in the entourage be cleansed or killed?

28. How does a shield feed back to cause both a shield and a lasgun to explode?
• Maybe shields work by repelling all impinging objects.
• The shield repels the lasgun beam back to the lasgun and also overloads itself?
• Sensor equipment should be able to detect shields that work in this manner.

29. People somehow did not make the connections they should have made about other people:
• Gurney recalled the stories told of Muad'Dib, the Lisan al-Gaib.
- Why didn't he remember that Fremen had called Paul "Lisan al-Gaib"?
• Paul introduced Stilgar and Gurney to each other.
- Why didn't either remember the other from when Idaho was told not to unsheath the crysknife?
- Gurney's name was not used while Stilgar was there.
• Why didn't Gurney notice that Jessica was a Reverend Mother from conversation?
- Did he think a Reverend Mother could be a traitor?

30. How do people in these sci-fi stories put up with these things that outrage people on earth?
• Eugenics - Bene Gesserit breeding program is eugenics and often uses incest.
• Abortions - Part of the selective part of selective breeding?
• Monopoly - The Spacing Guild and CHOAM are monopolies.
• Castes (faufreluches) prevail throughout the empire.
• Polygamy and concubines
• Government controlled economy
• Unelected leaders (emperor, duke, baron, count, etc)
- Why so many different titles?
• Hereditary succession of leaders

31. There are errors in the map and in the cartographic notes.
• OH Gap is on the map where Old Gap should be.
• Cave of Riches is on the map where the Cave of Ridges is supposed to be.
• The Basis for Latitude (meridian through Observatory Mountain) should be Basis for Longitude.

32. Just what is an ornithopter? An ornithopter is a wing-flapping flying machine.
- It has all of the following:
• Wing controls
• Wing motion, cup, dip, and wingbeats
• Wing rotors
• Turbines
• Jetpods, tailpods
• Afterjets
• Jet brakes
• Attitude jets
• It can bank.
• Can it waggle its wings (bank back and forth repeatedly)???

Is there a pilot's license for flying ornithopters? Many seem to know how.

The lack of air traffic control is strange. They just get into 'thopters and take off.

33. It's obvious that Herbert does not understand religion.
- He sees it as a mumbo-jumbo of strange phrases and concepts:
• He puts religious sayings in the book with no explanation.
• Gurney obviously sees religion as nothing but "prattle".
• Fremen worship sandworms???
• Bene Gesserit uses trickery to make things seem miraculous.
• Pardot Kynes (Liet's father) said that religion and law must be the same. Disobedience is a sin.
• Plenty of religion, but no plan for personal salvation.
• They see a savoir as a warrior.