Min Min light

Min Min light

Channel Country, Queensland

An old hotel on the road between Winton and Boulia, about 1925. It is not the Min Min, which had gone years before this was taken, but it stands on the same road and was the same kind of place: a verandah, a chimney, and a very long way to the next one.

Appearance	A ball of light, about the size of a football
Height	Near eye level
Behaviour	Follows the observer
Reported since	1918 at the latest[1]
Region	The Channel Country, western Queensland
Nearest town	Boulia
The account of it
Cause	Fata Morgana of an ordinary light
Source distance	Tens to hundreds of kilometres
Published	J. D. Pettigrew, 2003[2]
Reproduced deliberately	Yes
Witnesses to that	Six
Answered in the literature	No
Accepted at Boulia	No

The Min Min light is a luminous appearance reported from the Channel Country of western Queensland, described with unusual consistency as a ball of light roughly the size of a football, hanging near eye level, which keeps pace with a traveller and cannot be approached.^[1] Accounts run back at least to 1918 and probably much further, and it is the best-known apparition in Australia.

In 2003 the optical physiologist John Douglas Pettigrew published an account of it in Clinical and Experimental Optometry: it is a Fata Morgana, carrying the light of an ordinary source – a vehicle, a homestead, a camp fire – from tens or hundreds of kilometres beyond the horizon to an observer who has no reason to suspect the source exists.^[2] He then went out and made one.

The light

The descriptions are the strongest evidence that something is actually being seen. Witnesses over more than a century agree on the size, on the height above the ground, and on the two behaviours that make the thing memorable: it follows, and it cannot be reached. Riders reported it pacing them for miles; motorists report it keeping station with the car and then, on being driven at, retreating.

The name is usually attached to the Min Min Hotel, a staging post on the track between Boulia and Winton, and the first widely repeated account belongs to a stockman who saw the light near its site in 1918. That derivation is not settled: a source in an Aboriginal language has also been proposed, and neither has been substantiated.^[5] A sighting of 1838 is sometimes offered as the earliest, from Six Months in South Australia, but it is not clear that the author was describing this at all.

Boulia has since built a good deal on it. The Min Min Encounter, opened in April 2000, is a forty-five-minute animatronic show, and it is the reason a number of people drive to Boulia.

The explanation

The mechanism is the one set out at Fata Morgana, applied at night to a point source instead of by day to a coastline.

The Channel Country from the International Space Station, 2016: the Georgina, Burke and Hamilton rivers braiding out into a floodplain more than thirty kilometres wide. Nothing in it stands up. A duct laid over country like this has nothing to break it, which is how a light can arrive from three hundred kilometres away.

The Channel Country supplies the conditions almost to order: a hot day, a clear sky, and a cold night, which lays a sheet of cold dense air on the ground beneath warmer air above. That is a temperature inversion, the same arrangement that produces looming over cold water; where it is steep enough it becomes a duct, and light entering at a shallow angle is bent back down as fast as it rises and travels along the ground instead of leaving it. The Novaya Zemlya effect is the same trapping at polar latitudes.

"The Min Min light occurs when light, from a natural or man-made source, is refracted to an observer who is tens, or even hundreds, of kilometres away, by an inverted mirage, or Fata Morgana."
– J. D. Pettigrew, 2003

The distances are the part that defeats intuition, and they are why the explanation took so long to arrive. Watching one such light, Pettigrew's party fixed its bearing with a car compass and found that they had to drive five kilometres before the bearing shifted at all, which put the source over 300 kilometres off and far below the horizon. A vehicle was afterwards found to have been travelling towards them at the time.^[3]

The demonstration

This is the part that distinguishes the episode, and there is very little else like it in this encyclopedia.

Having an explanation, Pettigrew went out to produce the phenomenon deliberately. He chose a night with the right conditions – a cool evening after a hot day, and almost no wind – drove ten kilometres away, and took the car down over a slight rise into a watercourse, so that it stood well below the line of sight of the observers he had left behind. Six of them watched his headlights rise up over the horizon and hang there, as a soft ball of light at about eye level, doing what the Min Min light does.

It is worth being plain about how unusual that is. The literature of this encyclopedia is largely made of people who observed a real effect and then accounted for it badly: Hieronymus Unlonn measured refraction correctly for twenty years and attributed it to the disposition of the air. Anders Theodor Jung did better and tabulated the lot, but he tabulated observations others had made. What is on offer here is the third thing: an account, and then the effect made to happen on purpose, at a time and place announced in advance, in front of people who could see whether it worked. The Bedford Level experiment is the corpus's other example, and it took a wager to arrange.

Why it follows

The following is the feature every account mentions and the one that sounds least like optics, and it is the easiest part to explain.

A mirage has no position. There is no object hanging in the air at a place one could walk to; there is a set of ray paths that happen to arrive at a particular eye. Move the eye, and the set of paths that can reach it changes, and the image is reassembled somewhere slightly different. The light therefore travels with whoever is looking at it, holds its bearing as the car moves, and recedes when driven at – all of which is exactly what a distant, ducted source must appear to do, and none of which any object could do.

The apparition is thus not merely explained but explained in the detail that made it seem inexplicable. That is a stronger result than an explanation which accounts for the phenomenon and quietly drops its most striking feature.

Since

The paper has not been answered. It is also not the account given in Boulia, where the visitor centre advises that many have tried to establish the light's origin and that nobody has yet succeeded.^[4]

There is no scandal in this. A town that has been telling a story for a century, and has built a theatre for it, is not obliged to retire it because an optometry journal has been persuaded; and the mirage, being real, will go on producing the light whatever anybody has published. The result is a phenomenon that is simultaneously accounted for in the literature and unexplained on the ground, which is a condition several subjects in this encyclopedia would recognise.

The inverse arrangement is Vic Tandy's laboratory, where the apparition was diagnosed and abolished on the premises, and the explanation offered for it afterwards went into general circulation in a form the literature has since declined.

See also

• Fata Morgana – the mirage this is a case of, and the mechanism in full
• Looming – the same refraction, without the duct
• Novaya Zemlya effect – the same duct, carrying the Sun instead of a car
• The Bedford Level experiment – the corpus's other case of somebody going out to settle it in the field
• Anders Theodor Jung – who did this work for the northern shores, and without the animatronics
• Reuelsee – a lake conjured by the opposite arrangement, warm ground under cool air, and just as absent
• Hieronymus Unlonn – who observed the same physics and never once staged it
• Vic Tandy – the inverse case: an apparition settled on the premises, and over-explained everywhere else

References

1. ^ The widely repeated first account belongs to a stockman near the site of the Min Min Hotel, in 1918; the hotel had been destroyed by fire some years before. An 1838 report in Six Months in South Australia is sometimes cited as earlier; the description does not clearly match. Aboriginal accounts of lights in the country long predate both, and are not the same tradition.
2. ^ J. D. Pettigrew, "The Min Min light and the Fata Morgana: An optical account of a mysterious Australian phenomenon", Clinical and Experimental Optometry 86:2 (March 2003), 109–120, doi:10.1111/j.1444-0938.2003.tb03069.x. Pettigrew came to the country studying nocturnal birds and encountered the light in the ordinary way.
3. ^ The method is triangulation with the crudest instrument to hand. A nearby light changes its bearing quickly as the observer moves; one that holds its bearing over five kilometres of travel is a very long way off. The figure of 300 kilometres is a lower bound arrived at in the field, not a measurement.
4. ^ The hotel derivation is the usual one and is repeated everywhere, including here; it has not been established. A derivation from an Aboriginal language has also been offered. This article names the hotel because that is what the accounts do, not because the point is settled.
5. ^ The Min Min Encounter and Boulia visitor information centre. The position is not evasive: it is what the town's own material says, and it has said it since the attraction opened in April 2000, three years before the paper.

External links

• The Min Min light and the Fata Morgana – Pettigrew's paper in Clinical and Experimental Optometry (2003)
• UQ scientist unlocks secret of Min Min lights – the University of Queensland's announcement, 27 March 2003
• Mystery of the Min Min lights explained – ABC Science's account of the field demonstration
• Min Min Encounter, Boulia – the Boulia Shire Council's visitor centre
• Old hotel on the road between Winton and Boulia – the photograph reproduced above, ca. 1925, John Oxley Library, State Library of Queensland
• Channel Country, Northwest Queensland – the astronaut photograph reproduced above, ISS048-E-71898, taken 5 September 2016; NASA Earth Observatory