Date in year · 1991 · The 1990s

October 15, 1991

On October 15, 1991, the "Oh-My-God particle", an ultra-high-energy cosmic ray measured at 40,000,000 times that of the highest energy protons produced in a particle accelerator, is observed at the University of Utah HiRes observatory in Dugway Proving Ground, Utah. The year's #1 song was "(Everything I Do) I Do It for You" by Bryan Adams. Duván Zapata, Thiago Alcântara, Cédric Bakambu would arrive in the same year.

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Year

1991

1990s

Featured · October 15, 1991

The "Oh-My-God particle", an ultra-high-energy cosmic ray measured at 40,000,000 times that of the highest energy protons produced in a particle accelerator, is observed at the University of Utah HiRes observatory in Dugway Proving Ground, Utah.

The Oh-My-God particle (as physicists dubbed it) was an ultra-high-energy cosmic ray detected on 15 October 1991 by the Fly's Eye camera in Dugway Proving Ground, Utah, United States. As of 2026, it is the highest-energy cosmic ray ever observed. 9)×1020 eV (320 exaelectronvolt).

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Around 1991

The year in brief

1991 (MCMXCI) was a common year starting on Tuesday of the Gregorian calendar, the 1991st year of the Common Era (CE) and Anno Domini (AD) designations, the 991st year of the 2nd millennium, the 91st year of the 20th century, and the 2nd year of the 1990s decade.

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What happened

On October 15, 1991

  1. 1991 The "Oh-My-God particle", an ultra-high-energy cosmic ray measured at 40,000,000 times that of the highest energy protons produced in a particle accelerator, is observed at the University of Utah HiRes observatory in Dugway Proving Ground, Utah.

    Ultra-high-energy cosmic ray detected in 1991

    The Oh-My-God particle (as physicists dubbed it) was an ultra-high-energy cosmic ray detected on 15 October 1991 by the Fly's Eye camera in Dugway Proving Ground, Utah, United States. As of 2026, it is the highest-energy cosmic ray ever observed. 9)×1020 eV (320 exaelectronvolt).

  2. 1991 The leaders of the Baltic States, Arnold Rüütel of Estonia, Anatolijs Gorbunovs of Latvia and Vytautas Landsbergis of Lithuania, signed the OSCE Final Act in Helsinki, Finland.

    Three countries east of the Baltic Sea

    The Baltic states or the Baltic countries is a geopolitical term encompassing Estonia, Latvia, and Lithuania. All three countries are members of NATO, the European Union, the Eurozone, the Baltic Assembly, and the OECD. The three sovereign states on the eastern coast of the Baltic Sea are sometimes referred to as the "Baltic nations", less often and in historical circumstances also as the "Baltic republics", the "Baltic lands", or simply the Baltics.

Arrivals

Born on October 15, 1991

Brock Nelson 1991– American ice hockey player (born 1991)

Elsewhere that year

Other moments from 1991

The class of 1991

Others born in 1991

Duván Zapata 1991– Colombian footballer
Thiago Alcântara 1991– Spanish footballer
Cédric Bakambu 1991– Congolese footballer
Brennan Poole 1991– American racing driver
Lionel Carole 1991– French professional footballer
Oliver Norwood 1991– English-born Northern Irish international footballer

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The year 1991 1991 retrospective Every october 15 The calendar date One year earlier 1990

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The full year 1991 Every october 15, through history October 15 One year earlier 1990