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Chandra’s image of SN 1006 shows X-rays from multimillion degree gas (red/green) and high-energy electrons (blue). In the year 1006 a “new star” appeared in the sky and in just a few days it became brighter than the planet Venus. We now know that the event heralded not the appearance of a new star, but the cataclysmic death of an old one. It was likely a white dwarf star that had been pulling matter off an orbiting companion star. When the white dwarf mass exceeded the stability limit (known as the Chandrasekhar limit), it exploded. Material ejected in the supernova produced tremendous shock waves that heated gas to millions of degrees and accelerated electrons to extremely high energies. Photo and caption: Wikipedia.

Editor’s note: Just over a thousand years ago, the stellar explosion known as Supernova SN 1006 was observed and recorded by Fatimid astronomer Ibn Ridwan (see Aliza Moledina’s piece Ibn Ridwan and Supernova 1006). Scientists have now studied a text by Avicenna which describes the explosion in his Kitab al-Shifa (Book of Healing), a masterpiece written in several volumes that tackles Earth sciences, logic, philosophy, physics, mathematics, astronomy, music, psychology and theology. The report on the findings that appears below is taken from the April 24th, 2016, issue of the popular Russian science magazine http://www.sputniknews.com. The explanation of the findings by German scientists in Avicenna’s Book of Healing may be read at the Astronomical Notes Journal by clicking on http://arxiv.org/pdf/1604.03798v1.pdf.

For the first time, scientists have studied a text by noted tenth century polymath Ibn Sina (known as Avicenna in Latin), in which the scholar described observations of a supernova in the year 397 of the Islamic Hijri calendar, calculated as 1,006 AD.

Ibn Sina (980-1037 AD) was a Persian physician and philosopher who is regarded as the most famous and influential of the medieval Islamic world’s philosopher-scientists.

The German scientists who studied Ibn Sina’s account believe it was written when he was in present-day Iran, Turkmenistan or Uzbekistan, most probably the latter. They translate his description of the supernova’s form, direction and appearance.

Ibn Sina wrote that the object was “tailless,” which distinguished it from the more common transient objects, comets with tails.

The new star was “getting fainter and fainter until it disappeared,” and that it “became fainter and disappeared,” he wrote.

“At the beginning it was towards a darkness and greenness, then it began to throw out sparks and then it became more and more whitish.”

To mark the 1,000th birth anniversary of the most influential of Islam’s philosopher-scientists, UNESCO minted this commemorative medal in 1980. Designed by sculptor-medallist Victor Douek, the obverse depicts a scene showing Avicenna surrounded by his disciples. Photo: UNESCO/N. Burke. Copyright.

His Arabic-language report is one of several historical observations of supernovas that have helped scientists in their understanding of these celestial events, and adds to previous information about the supernova in 1006 AD from observers in Yemen, Morocco, China and Japan.

Contemporary scientists have also provided today’s astronomers with information about supernova sightings in 1054 (from Eastern Asia and Arabia), 1181 (Eastern Asia), 1572 and 1604 AD (the latter two sighted in Eastern Asia and Europe).

“Historic reports can deliver the date of the observation (hence, the age of the supernova remnant and, if existing, of the neutron star) together with a light curve (hence, possibly the supernova type), sometimes the color and its evolution, and the position of the supernova,” the scientists explained in their paper, which can be viewed by clicking http://arxiv.org/pdf/1604.03798v1.pdf.

Date posted: May 1, 2016.

Please also read Aliza Moledina’s Ibn Ridwan and Supernova 1006 

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