|Rare Lowitz Arc, Alpharetta, Georgia
Tom Faber experienced his second display (the first) of rare Lowitz arcs on 21st January '13. "Between 3:00-3:30PM EST I saw sundogs, a 22° halo, upper tangent arc, a Parry arc, a circumzenithal arc, part of the parhelic circle with a faint 120° parhelia and an upper Lowitz arc! ©Tom Faber, shown with permission.
|Johann Tobias Lowitz was the first to report these arcs in a publication of the St Petersburg Imperial Academy of Sciences 1794 where he was Professor of Chemistry.
The Academy, founded by Peter the Great, was a major intellectual centre with many eminent European scientists and other scholars.
Lowitz was born in Göttingen in 1757 and moved at the age of ten to St Petersburg with his father who was also an Academician. At age 17 he accompanied his father on an expedition to the Caspian Sea where both were captured by rebels. Tobias escaped but his father was killed.
He subsequently studied back in Göttingen before returning to Russia.
His chemical studies established many basic laboratory methods, he was the first to produce anhydric ethanol – a task requiring some ingenuity – and he prepared many compounds.
It is ironic that after years of practising chemical research he is now best known for his observation in the skies of Petersburg on June 18, 1790 of what has proven to be one of the most enigmatic and elusive of the ice halos.
|Lowitz arcs are often most sought as short arcs extending from sundogs to meet a 22 degree halo. There is a hint of those in the images at right.
However, a much better search location is between upper tangent and Parry arcs. The upper Lowitz arc extends upwards from the 22 degree halo, crosses the tangent arc and finally becomes tangent to the Parry.
Always search this area when the sun is moderately high and a Parry arc is visible.