Solar X-ray Imager (SXI) are full-disc X-ray instruments observing the

Sun The Sun is the star at the center of the Solar System. It is a nearly perfect ball of hot plasma, heated to incandescence by nuclear fusion reactions in its core. The Sun radiates this energy mainly as light, ultraviolet, and infrared radi ...

aboard

GOES Goes () is a city and municipality in the southwestern Netherlands on Zuid-Beveland, in the province of Zeeland. The city of Goes has approximately 27,000 residents. History Goes was founded in the 10th century on the edge of a creek: de Korte ...

satellites. The SXI on GOES 12 was the first of its kind and allows the U.S.

NOAA The National Oceanic and Atmospheric Administration (abbreviated as NOAA ) is an United States scientific and regulatory agency within the United States Department of Commerce that forecasts weather, monitors oceanic and atmospheric conditio ...

to better monitor and predict

space weather Space weather is a branch of space physics and aeronomy, or heliophysics, concerned with the time varying conditions within the Solar System, including the solar wind, emphasizing the space surrounding the Earth, including conditions in the ma ...

Operation

The Solar X-ray Imager aboard the

GOES 12 GOES-12, known as GOES-M before becoming operational, is an American weather satellite, which is part of the US National Oceanic and Atmospheric Administration's Geostationary Operational Environmental Satellite system. It was launched on July 23, ...

GOES 13 Goes () is a List of cities in the Netherlands by province, city and List of municipalities of the Netherlands, municipality in the southwestern Netherlands on Zuid-Beveland, in the Provinces of the Netherlands, province of Zeeland. The city of G ...

GOES 14 GOES-14, known as GOES-O prior to reaching its operational orbit, is an American weather satellite, which is part of the US National Oceanic and Atmospheric Administration (NOAA)'s Geostationary Operational Environmental Satellite (GOES) system. ...

, and

GOES 15 GOES-15, previously known as GOES-P, is an American weather satellite, which forms part of the Geostationary Operational Environmental Satellite (GOES) system operated by the U.S. National Oceanic and Atmospheric Administration. The spacecraft was ...

NOAA

weather satellites A weather satellite or meteorological satellite is a type of Earth observation satellite that is primarily used to monitor the weather and climate of the Earth. Satellites can be polar orbiting (covering the entire Earth asynchronously), or geo ...

is used for early detection of

solar flares A solar flare is an intense localized eruption of electromagnetic radiation in the Sun's atmosphere. Flares occur in active regions and are often, but not always, accompanied by coronal mass ejections, solar particle events, and other solar phe ...

coronal mass ejection A coronal mass ejection (CME) is a significant release of plasma and accompanying magnetic field from the Sun's corona into the heliosphere. CMEs are often associated with solar flares and other forms of solar activity, but a broadly accepted ...

s (CMEs), and space phenomena that impact

human spaceflight Human spaceflight (also referred to as manned spaceflight or crewed spaceflight) is spaceflight with a crew or passengers aboard a spacecraft, often with the spacecraft being operated directly by the onboard human crew. Spacecraft can also be ...

and military and commercial

satellite communications A communications satellite is an artificial satellite that relays and amplifies radio telecommunication signals via a transponder; it creates a communication channel between a source transmitter and a receiver at different locations on Earth. C ...

. The Solar X-ray Imager was the first

X-ray telescope An X-ray telescope (XRT) is a telescope that is designed to observe remote objects in the X-ray spectrum. In order to get above the Earth's atmosphere, which is opaque to X-rays, X-ray telescopes must be mounted on high altitude rockets, balloon ...

to take a "full-disk" image of the Sun, providing forecasters with the ability to detect solar storms and real-time solar forecasting by the

Space Weather Prediction Center The Space Weather Prediction Center (SWPC), named the Space Environment Center (SEC) until 2007, is a laboratory and service center of the US National Weather Service (NWS), part of the National Oceanic and Atmospheric Administration (NOAA), loca ...

(SWPC).

Imagery

The SXI aboard GOES 12 is a Wolter Type I (

Wolter telescope A Wolter telescope is a telescope for X-rays that only uses grazing incidence optics – mirrors that reflect X-rays at very shallow angles. Problems with conventional telescope designs Conventional telescope designs require reflection or refract ...

) grazing incidence X-ray telescope designed to record coronal images in continuous sequence at 1-minute intervals. The Solar X-ray Imager obtains images at multiple

wavelengths In physics, the wavelength is the spatial period of a periodic wave—the distance over which the wave's shape repeats. It is the distance between consecutive corresponding points of the same phase on the wave, such as two adjacent crests, tro ...

on the

electromagnetic spectrum The electromagnetic spectrum is the range of frequencies (the spectrum) of electromagnetic radiation and their respective wavelengths and photon energies. The electromagnetic spectrum covers electromagnetic waves with frequencies ranging from ...

from 6 to 60

angstrom unit The angstromEntry "angstrom" in the Oxford online dictionary. Retrieved on 2019-03-02 from https://en.oxforddictionaries.com/definition/angstrom.Entry "angstrom" in the Merriam-Webster online dictionary. Retrieved on 2019-03-02 from https://www.m ...

s (Å). The imagery obtained by the XSI and XRS on GOES 12 allowed forecasters to see space phenomena such as

coronal hole A coronal hole is a temporary region of relatively cool, less dense plasma in the solar corona where the Sun's magnetic field extends into interplanetary space as an open field.Freedman, Roger A., and William J. Kaufmann III. "Our Star, the Sun. ...

s, whose

geomagnetic Earth's magnetic field, also known as the geomagnetic field, is the magnetic field that extends from Earth's interior out into space, where it interacts with the solar wind, a stream of charged particles emanating from the Sun. The magnetic fi ...

and

proton A proton is a stable subatomic particle, symbol , H+, or 1H+ with a positive electric charge of +1 ''e'' elementary charge. Its mass is slightly less than that of a neutron and 1,836 times the mass of an electron (the proton–electron mass ...

storms impact

electrical grid An electrical grid is an interconnected network for electricity delivery from producers to consumers. Electrical grids vary in size and can cover whole countries or continents. It consists of:Kaplan, S. M. (2009). Smart Grid. Electrical Power ...

systems on Earth as well as

radio communications Radio is the technology of signaling and communicating using radio waves. Radio waves are electromagnetic waves of frequency between 30 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a transmit ...

and satellite communications systems.

Failure and termination of the GOES 12 instrument

The XSI and XRS sensors on GOES 12 failed due to a problem with the electrical system which controls the north-south motion functionality of the instruments on April 12, 2007. The SXI and XRS currently have the ability to capture and record images. Due to limited field of view of the

x-ray An X-ray, or, much less commonly, X-radiation, is a penetrating form of high-energy electromagnetic radiation. Most X-rays have a wavelength ranging from 10 picometers to 10 nanometers, corresponding to frequencies in the range 30&nb ...

instrumentation, the XSI and XRS and been permanently deactivated.

References

{{Sun spacecraft 2001 in spaceflight Spacecraft instruments Solar observatories

Operation

Imagery

Failure and termination of the GOES 12 instrument

See also

References