The last astronomer in the land of the Tuareg
Like two other tourists traveling as a shaman or as a wise Bedouin classify, who aids the farmer with his star client and monitors the proper observance of sowing and harvesting dates. And why they are driven home in the knowledge that they have just met one of the last local astronomers from the land of the Tuareg ...
three-star astronomy
worked in the seventies of the last century, I was the youngest developer for a no longer existing, large electronics company in the antenna laboratory, where once the giant bowls of ground stations in the modern communications satellite designed. part of my job the calculation of all conceivable sources of error and the antenna noise temperature, which played at that time for the data transmission an important role.
To measure the antenna noise we needed at that time stars such as the strong noise source, Cassiopeia A, a remnant of a supernova in the right ascension 23h 21m and declination +58 ° 33 '. Another potential source was Cygnus A, provided they have at least 20 ° above the horizon. Sources below about 20 degrees elevation are useless because the radiation temperature of the soil at 300 Kelvin is much too strong. A rather weak noise source Taurus A forms in the Taurus (the Crab Nebula) in right ascension 5h 31 'and declination +21 ° 58'.
could with these sources will review the accuracy of the positioning and the noise of the antenna. With diameters of 18-25 m were caused by the huge parabolic vulnerable to mechanical stresses, the deviations from the ideal paraboloid shape. For the composition of a continuous series of measurements were needed at different elevation angles sources. The ratios of the main sources of noise made my basic knowledge in the field of astronomy. It was all Three to four stars astronomy.
The gateway to the desert
undertook in the spring of these years, I with my young, small family on a tour in Tunisia, where in addition to the coastal region with the Moorish, Punic and Roman sites and the desert in the south of the country with its oases, the foothills of the Atlas Mountains and the salt lakes on the program were.
It was on this trip to Tunis over El Dijem, Sfax, Gabes, Matmata and Gafsa because we all ss in the south, the gateway to the desert reached that is called because of the dunes of the Sahara Douz . It is a tiny, dusty oasis town, which now can not produce truly great story.
Douz environment with the center of the part still semi-nomadic Mrazig is strain that will descend from the Beni Hilal . As the government leads the people to settle down, reduces the number of nomads from year to year and you will find there today no more Tuareg. Douz earlier, however, was an important stop on the overland caravan routes. The removal of the caravan has been offset by tourism. Per year are counted in the region of Douz 320 000 overnight stays. The desert tourism harms However the environment because of excessive water consumption in the oases.
place in the modern center of Douz Thursday instead of the largest weekly market in southern Tunisia to the sedentary and nomadic buyers and sellers from the area, sometimes together come from Algeria. Even earlier Tuareg moved from southern Algeria with their caravans to the market at Douz. So it was not unusual to encounter in this place just before a Thursday, a foreign Tuareg.
"Touareg" in the "seven-star hotel"
Our hotel in Douz was a so-called "seven-star hotel", which in a black tent was housed. The name referred to a dozen holes in the black tents, which should provide the observers with a closer look in any direction at least 7 stars. We disrupted the bountiful fresh air culture means. It was really comfortable in this huge tent.
to promote the local weaving we had been dressed for dinner in traditional dress with white djellaba and colorful turban decorated . Even that was no problem and soon I had forgotten that we ever wore such exotic clothing.
evening walk on the edge of the desert
And it was here most peaceful in the evening hours after sunset that I took a walk in the oasis, while my wife with our son who preferred to stay at the hotel. It was during dinner instantly became completely dark and so I moved gently under the moonless sky to the edge of town on a sandy path between meter-high stalks that looked like maybe cane or a kind of papyrus. that grows here on the banks of a pond or marshy terrain.
appeared in the darkness, the eerie air and wind, and while my eyes became accustomed to the darkness, I suddenly heard a strange rustling. It sounded as if a tiny toys were forgotten by a child in the sandbox and now on its last legs further rattled by the spring tension had completely broken down ...
Carefully I walked further along the meandering path between the towering, black reeds. Then I tell two people on a low wall, playing with a device that apparently caused the noise. Both were so busy that they do not get me heard and saw at first as I stood beside them.
" Bon soir, monsieur madame y "
I greeted the couple who housed perhaps as a middle-aged couple in a tourist hotel was. They greeted back in French.
the unit on the wall was apparently a camera, so you can scan the night sky in complete darkness for some time. For these shots of the night sky but it takes a special tool. The stars are seen from Earth is not over. Since the earth as all the planets rotate around its axis, the sky cut shifts at all times. Why do you photograph the night sky for scientific purposes, with a tracking system, which compensates for the earth's rotation. Without such a body would only the polar star in the north represented approximately as a fixed star. All other stars are shown as circular arcs around the center around.
The rustling noise came from a now Federzuguhrwerk, which was the camera tracked the stars . The turntable and the transmission came from our own production and the rotational axis was aligned with a polar scope is at the North Star.
selected for such admissions one moonless nights, far from big cities with all that artificial light and a cloudy atmosphere. Thus were the only two tourists traveled specifically to this day all the way to the edge of the desert at this to take pictures.
I am interested in your machine and explained that the form works with Cassiopeia, Cygnus and Taurus is an important part of my subject area.
The mention of these heavenly bodies electrified the research pair and there ensued a lively discussion on the performance limits of tracking at night photography. Such systems allow exposure times from about 30 minutes at 28 mm wide-angle lens and 5 minutes at 200 mm telephoto lens.
The departure of the last shamans
After i n their discussion on K assiopeia, Cygnus and Taurus we changed the subject and took the remarkable Orion under the magnifying glass that can be seen in Central Europe in the evening sky to April and a mythical sky hunter supposed to represent. The striking constellation of ancient peoples of different meanings attributed. Most importantly perhaps the definition of the important harvest seasons, which I had noticed during the teaching of history as an old country sayings was:
" The threshing comes with the giant Orion .
for the Orion is not visible from April to July and only then at home began threshing.
And some fell back with one. If the constellation Scorpio rises in the east, Orion must leave the sky in the west. Thus, the two opponents are never together in the sky. the morning and last of Orion the field work begins:
" When the Pleiades flee mighty Orion giant then thoughtfully cultivate the field, as I command you .
My wisdom and my knowledge impressed the French couple and they expressed their amazement that they had obtained in this remote oasis still so much of the ancient astronomical knowledge!
then initially I was speechless for a few seconds ....
no means I had been aware of that I still have the djellaba and the brightly decorated wore turbans. Obviously it was too dark to recognize me as a West European. My French sounded determined quite bumpy, but for a true- Tuareg certainly acceptable.
The two tourists looked at me certainly as a local who as a shaman or wise Bedouin the local farmer with his astronomy and assists the proper observance of the sowing and harvesting dates monitored.
This was too good to be true. Of course I would have to explain now that I were a Western European technicians and my wisdom to the Orion only inaccurate details of a distant lesson came from. To tell you, however, that she brought to fake and that I was no Africans, but then I do not have the heart. It would also hurt them unnecessarily in their pride ...
It would be better, the couple in the certainty to have to travel back, that guards in the desert city Douz still the old secret knowledge of the astronomical sky clock, which continues to operate if been all the oil is burned and the survivors again as the Bedouin have to live in the desert. So I let the French pair in the madness of my knowledge, passed me politely in French, and followed with pride and walking upright on my way.
I am also sure that both pairs of eyes after my departure for a while must have followed completely surprised - in the knowledge that they had just adopted one of the last local astronomers from the land of the Tuareg ...
Appendix: The constellations
Cassiopeia is visible year-round in Central Europe. The region of Cassiopeia is very star-rich, since the Milky Way runs through the constellation. Several open cluster can be seen here.
The Swan (Cygnus Latin) is a constellation north of the celestial equator. The Swan is a conspicuous constellation in the summer and autumn sky. The swan pulls the bright band of the Milky Way, so the constellation is full of interesting stars and nebulous objects.
The bull (Latin Taurus, astronomical sign: ♉) is a constellation of the ecliptic. The bull is north of the prominent Orion in the sky. The striking reddish star Aldebaran is the Dar. eye of the bull The bull can be observed from fall to spring.
The Orion is a constellation on the celestial equator. The Orion is situated between the river Eridanus and the unicorn on the celestial equator. This should be seen in Central Europe as of August (morning sky) to April (evening sky), in the Southern Hemisphere at higher latitudes, such as July-May
