The Siberian orange snow of 2007 was an anomalous phenomenon that occurred in early February 2007. Beginning on 31 January 2007, an orange-tinted snow fell across an area of in

Omsk Oblast Omsk Oblast () is a federal subjects of Russia, federal subject of Russia (an oblast), located in southwestern Siberia. The oblast has an area of . Its population is 1,977,665 (Russian Census (2010), 2010 Census) with the majority, 1.12 million, ...

Siberian Federal District Siberian Federal District ( rus, Сибирский федеральный округ, p=sʲɪˈbʲirskʲɪj fʲɪdʲɪˈralʲnɨj ˈokrʊk) is one of the eight federal districts of Russia. Its population was 17,178,298 according to the 20 ...

, Russia, approximately from Moscow, as well as into the neighboring

Tomsk Tomsk (, ) is a types of inhabited localities in Russia, city and the administrative center of Tomsk Oblast in Russia, on the Tom (river), Tom River. Population: Founded in 1604, Tomsk is one of the oldest cities in Siberia. It has six univers ...

and Tyumen Oblasts. It was unclear what caused the orange snow. Speculation ranged from pollutants to a sandstorm in neighboring

Kazakhstan Kazakhstan, officially the Republic of Kazakhstan, is a landlocked country primarily in Central Asia, with a European Kazakhstan, small portion in Eastern Europe. It borders Russia to the Kazakhstan–Russia border, north and west, China to th ...

Description

The orange snow was malodorous, oily to the touch, and reported to contain four times the normal level of

iron Iron is a chemical element; it has symbol Fe () and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, forming much of Earth's o ...

. Though mostly orange, some of the snow was red or yellow. It affected an area with about 27,000 residents. It was originally speculated that it was caused by industrial pollution, a rocket launch or even a nuclear accident. It was later determined that the snow was non-toxic; however, people in the region were advised not to use the snow or allow animals to feed upon it. Colored snow is uncommon in Russia but not unheard of, as there have been many cases of black, blue, green and red snowfall.

Possible causes

This orange snow may have been caused by a heavy sandstorm in neighboring

. Tests on the snow revealed numerous sand and clay dust particles, which were blown into Russia in the upper stratosphere. The speculation that the coloration was caused by a

rocket A rocket (from , and so named for its shape) is a vehicle that uses jet propulsion to accelerate without using any surrounding air. A rocket engine produces thrust by reaction to exhaust expelled at high speed. Rocket engines work entirely ...

launch from

Baikonur Baikonur ( ; ) is a city in Kazakhstan on the northern bank of the Syr Darya river. It is currently leased and administered by the Russian Federation as an enclave until 2050. It was constructed to serve the Baikonur Cosmodrome with adminis ...

in Kazakhstan was later dismissed, as the last launch before the event took place on 18 January 2007. Russia's environmental watchdog originally claimed that the colored snowfall was caused by industrial pollution, such as "waste from

metallurgical Metallurgy is a domain of materials science and engineering that studies the physical and chemical behavior of metallic elements, their inter-metallic compounds, and their mixtures, which are known as alloys. Metallurgy encompasses both the ...

plants." It stated that the snow contained four times the normal quantities of acids,

nitrate Nitrate is a polyatomic ion with the chemical formula . salt (chemistry), Salts containing this ion are called nitrates. Nitrates are common components of fertilizers and explosives. Almost all inorganic nitrates are solubility, soluble in wa ...

s, and iron. However, it would be nearly impossible to pinpoint a culprit if pollution were the cause, as there are various industries nearby, such as the city of

Omsk Omsk (; , ) is the administrative center and largest types of inhabited localities in Russia, city of Omsk Oblast, Russia. It is situated in southwestern Siberia and has a population of over one million. Omsk is the third List of cities and tow ...

, which is a center of the

oil industry The petroleum industry, also known as the oil industry, includes the global processes of exploration, extraction, refining, transportation (often by oil tankers and pipelines), and marketing of petroleum products. The largest volume products ...

in Russia.

References

{{Reflist Siberian Orange Snow, 2007 Siberian Orange Snow, 2007 Anomalous weather History of Omsk Oblast History of Siberia Snow

Description

Possible causes

See also

References