Solar cycle 22
Encyclopedia
Solar cycle 22 is the 22nd solar cycle
Solar cycle
The solar cycle, or the solar magnetic activity cycle, is a periodic change in the amount of irradiation from the Sun that is experienced on Earth. It has a period of about 11 years, and is one component of solar variation, the other being aperiodic fluctuations. Solar variation causes changes in...

 since 1755, when recording of solar sunspot
Sunspot
Sunspots are temporary phenomena on the photosphere of the Sun that appear visibly as dark spots compared to surrounding regions. They are caused by intense magnetic activity, which inhibits convection by an effect comparable to the eddy current brake, forming areas of reduced surface temperature....

 activity began. The solar cycle lasted 9.7 years, beginning in September 1986 and ending in May 1996. The maximum smoothed sunspot number (monthly number of sunspots averaged over a twelve month period) observed during the solar cycle was 158.5, and the minimum was 8. There were a total of 309 days with no sunspots during this cycle.

March 1989 geomagnetic storm

During March 1989, a severe geomagnetic storm
Geomagnetic storm
A geomagnetic storm is a temporary disturbance of the Earth's magnetosphere caused by a disturbance in the interplanetary medium. A geomagnetic storm is a major component of space weather and provides the input for many other components of space weather...

 caused the collapse of Hydro-Québec's electricity transmission system
Hydro-Québec's electricity transmission system
Hydro-Québec's electricity transmission system is an expansive, international power transmission system located in Quebec, Canada with extensions into the Northeastern United States...

. The geomagnetic storm causing this event was itself the result of a Coronal Mass Ejection
Coronal mass ejection
A coronal mass ejection is a massive burst of solar wind, other light isotope plasma, and magnetic fields rising above the solar corona or being released into space....

 on March 9, 1989. A few days before, on March 6, 1989, a very large X15 solar flare
Solar flare
A solar flare is a sudden brightening observed over the Sun surface or the solar limb, which is interpreted as a large energy release of up to 6 × 1025 joules of energy . The flare ejects clouds of electrons, ions, and atoms through the corona into space. These clouds typically reach Earth a day...

 also occurred.
At 2:44 am
12-hour clock
The 12-hour clock is a time conversion convention in which the 24 hours of the day are divided into two periods called ante meridiem and post meridiem...

 on March 13, 1989, a severe geomagnetic storm struck Earth
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...

.
The storm began on Earth with extremely intense auroras
Aurora (astronomy)
An aurora is a natural light display in the sky particularly in the high latitude regions, caused by the collision of energetic charged particles with atoms in the high altitude atmosphere...

 at the poles. The aurora could be seen as far south as Texas
Texas
Texas is the second largest U.S. state by both area and population, and the largest state by area in the contiguous United States.The name, based on the Caddo word "Tejas" meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in...

. As this occurred during the Cold War
Cold War
The Cold War was the continuing state from roughly 1946 to 1991 of political conflict, military tension, proxy wars, and economic competition between the Communist World—primarily the Soviet Union and its satellite states and allies—and the powers of the Western world, primarily the United States...

, many worried that a nuclear first-strike might be in progress. Others considered the intense auroras to be associated with the Space Shuttle mission STS-29
STS-29
-Mission parameters:*Mass:**Orbiter liftoff: **Orbiter landing: **Payload: *Perigee: *Apogee: *Inclination: 28.5°*Period: 90.6 min-Mission summary:Space Shuttle Discovery lifted off from Pad B, Launch...

, which had been launched on March 13 at 9:57:00 AM. The burst caused short-wave radio interference, including the disruption of radio signals from Radio Free Europe into Russia. It was initially believed that the signals had been jammed
Radio jamming
Radio jamming is the transmission of radio signals that disrupt communications by decreasing the signal to noise ratio. Unintentional jamming occurs when an operator transmits on a busy frequency without first checking whether it is in use, or without being able to hear stations using the frequency...

 by the Soviet government.


As midnight came and went, invisible electromagnetic forces were staging their own pitched battle in a vast arena bounded by the sky above and the rocky subterranean reaches of the Earth. A river of charged particles and electrons in the ionosphere flowed from west to east, inducing powerful electrical currents in the ground that surged into many natural nooks and crannies.


Some satellites in polar orbits lost control for several hours. GOES weather satellite communications were interrupted causing weather images to be lost. NASA's TDRS-1 communication satellite recorded over 250 anomalies caused by the increased particles flowing into its sensitive electronics. The Space Shuttle Discovery was having its own mysterious problems. A sensor on one of the tanks supplying hydrogen to a fuel cell was showing unusually high pressure readings on March 13. The problem went away just as mysteriously after the solar storm subsided.

The variations in the earth's magnetic field
Earth's magnetic field
Earth's magnetic field is the magnetic field that extends from the Earth's inner core to where it meets the solar wind, a stream of energetic particles emanating from the Sun...

 also tripped circuit breaker
Circuit breaker
A circuit breaker is an automatically operated electrical switch designed to protect an electrical circuit from damage caused by overload or short circuit. Its basic function is to detect a fault condition and, by interrupting continuity, to immediately discontinue electrical flow...

s on Hydro-Québec
Hydro-Québec
Hydro-Québec is a government-owned public utility established in 1944 by the Government of Quebec. Based in Montreal, the company is in charge of the generation, transmission and distribution of electricity across Quebec....

's power grid
Hydro-Québec's electricity transmission system
Hydro-Québec's electricity transmission system is an expansive, international power transmission system located in Quebec, Canada with extensions into the Northeastern United States...

. The utility's very long transmission lines and the fact that most of Quebec sits on a large rock shield
Canadian Shield
The Canadian Shield, also called the Laurentian Plateau, or Bouclier Canadien , is a vast geological shield covered by a thin layer of soil that forms the nucleus of the North American or Laurentia craton. It is an area mostly composed of igneous rock which relates to its long volcanic history...

 prevented current flowing through the earth, finding a less resistant path along the 735 kV power lines.

The James Bay
James Bay Project
The James Bay Project is a series of hydroelectric development with a combined installed capacity of over 16,000 megawatts built since 1974 for Hydro-Québec by the on the La Grande and other rivers of Northern Quebec....

 network went offline in less than 90 seconds, giving Quebec
Quebec
Quebec or is a province in east-central Canada. It is the only Canadian province with a predominantly French-speaking population and the only one whose sole official language is French at the provincial level....

 its second massive blackout
Power outage
A power outage is a short- or long-term loss of the electric power to an area.There are many causes of power failures in an electricity network...

 in 11 months. The power failure lasted 9 hours and forced the company to implement various mitigation strategies, including raising the trip level, installing series compensation
Flexible AC transmission system
A flexible alternating current transmission system is a system composed of static equipment used for the AC transmission of electrical energy. It is meant to enhance controllability and increase power transfer capability of the network...

 on ultra high voltage
High voltage
The term high voltage characterizes electrical circuits in which the voltage used is the cause of particular safety concerns and insulation requirements...

 lines and upgrading various monitoring and operational procedures. Other utilities
Public utility
A public utility is an organization that maintains the infrastructure for a public service . Public utilities are subject to forms of public control and regulation ranging from local community-based groups to state-wide government monopolies...

 in North America, the UK, Northern Europe and elsewhere implemented programs to reduce the risks associated with geomagnetically induced current
Geomagnetically induced current
Geomagnetically induced currents , affecting the normal operation of long electrical conductor systems, are a manifestation at ground level of space weather. During space weather events, electric currents in the magnetosphere and ionosphere experience large variations, which manifest also in the...

s.

Since 1995, geomagnetic storms and solar flare
Solar flare
A solar flare is a sudden brightening observed over the Sun surface or the solar limb, which is interpreted as a large energy release of up to 6 × 1025 joules of energy . The flare ejects clouds of electrons, ions, and atoms through the corona into space. These clouds typically reach Earth a day...

s have been monitored from the Solar and Heliospheric Observatory
Solar and Heliospheric Observatory
The Solar and Heliospheric Observatory is a spacecraft built by a European industrial consortium led by Matra Marconi Space that was launched on a Lockheed Martin Atlas IIAS launch vehicle on December 2, 1995 to study the Sun, and has discovered over 2100 comets. It began normal operations in May...

 (SOHO) joint-NASA
NASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...

-European Space Agency
European Space Agency
The European Space Agency , established in 1975, is an intergovernmental organisation dedicated to the exploration of space, currently with 18 member states...

 satellite.

August 1989 geomagnetic storm

In August 1989, another geomagnetic storm affected microchips
Integrated circuit
An integrated circuit or monolithic integrated circuit is an electronic circuit manufactured by the patterned diffusion of trace elements into the surface of a thin substrate of semiconductor material...

, leading to a halt of all trading on Toronto
Toronto
Toronto is the provincial capital of Ontario and the largest city in Canada. It is located in Southern Ontario on the northwestern shore of Lake Ontario. A relatively modern city, Toronto's history dates back to the late-18th century, when its land was first purchased by the British monarchy from...

's stock market
Stock market
A stock market or equity market is a public entity for the trading of company stock and derivatives at an agreed price; these are securities listed on a stock exchange as well as those only traded privately.The size of the world stock market was estimated at about $36.6 trillion...

. This geomagnetic storm was caused by a very large X20 solar flare
Solar flare
A solar flare is a sudden brightening observed over the Sun surface or the solar limb, which is interpreted as a large energy release of up to 6 × 1025 joules of energy . The flare ejects clouds of electrons, ions, and atoms through the corona into space. These clouds typically reach Earth a day...

 on August 16, 1989, which was even stronger than the X15 flare from March 6, 1989, referred above.

See also

  • March 1989 geomagnetic storm
    March 1989 geomagnetic storm
    The March 1989 geomagnetic storm was a severe geomagnetic storm that caused the collapse of Hydro-Québec's electricity transmission system. It occurred during solar cycle 22.-Geomagnetic storm and auroras:...

  • Solar variation
    Solar variation
    Solar variation is the change in the amount of radiation emitted by the Sun and in its spectral distribution over years to millennia. These variations have periodic components, the main one being the approximately 11-year solar cycle . The changes also have aperiodic fluctuations...

  • List of solar cycles
  • Sunspot
    Sunspot
    Sunspots are temporary phenomena on the photosphere of the Sun that appear visibly as dark spots compared to surrounding regions. They are caused by intense magnetic activity, which inhibits convection by an effect comparable to the eddy current brake, forming areas of reduced surface temperature....

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