Solar X-ray Imager

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Solar X-ray Imager (SXI) are full-disc X-ray instruments observing the Sun aboard GOES satellites. The SXI on GOES 12 was the first of its kind and allows the U.S. NOAA to better monitor and predict space weather.

Sun Star at the centre of the Solar System

The Sun is the star at the center of the Solar System. It is a nearly perfect sphere of hot plasma, with internal convective motion that generates a magnetic field via a dynamo process. It is by far the most important source of energy for life on Earth. Its diameter is about 1.39 million kilometers, or 109 times that of Earth, and its mass is about 330,000 times that of Earth. It accounts for about 99.86% of the total mass of the Solar System. Roughly three quarters of the Sun's mass consists of hydrogen (~73%); the rest is mostly helium (~25%), with much smaller quantities of heavier elements, including oxygen, carbon, neon, and iron.

Geostationary Operational Environmental Satellite

The Geostationary Operational Environmental Satellite system (GOES), operated by the United States' National Oceanic and Atmospheric Administration (NOAA)'s National Environmental Satellite, Data, and Information Service division, supports weather forecasting, severe storm tracking, and meteorology research. Spacecraft and ground-based elements of the system work together to provide a continuous stream of environmental data. The National Weather Service (NWS) and the Meteorological Service of Canada use the GOES system for their North American weather monitoring and forecasting operations, and scientific researchers use the data to better understand land, atmosphere, ocean, and climate interactions.

National Oceanic and Atmospheric Administration An American scientific agency within the US Department of Commerce that focuses on the oceans and the atmosphere

The National Oceanic and Atmospheric Administration is an American scientific agency within the United States Department of Commerce that focuses on the conditions of the oceans, major waterways, and the atmosphere.

Contents

Operation

The Solar X-ray Imager aboard the GOES 12, GOES 13, GOES 14, and GOES 15 NOAA weather satellites is used for early detection of solar flares, coronal mass ejections (CMEs), and space phenomena that impact human spaceflight and military and commercial satellite communications. [1] The Solar X-ray Imager was the first X-ray telescope 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 (SWPC). [2]

GOES 12 weather satellite

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, 2001, and spent its first 21 months in space as an on-orbit spare. From April 2003, the satellite took over the GOES-East position, providing coverage of the eastern half of the continental United States. In April 2010, GOES-East operations were taken over by GOES 13, and GOES 12 transitioned to the GOES-South location to devote time to South American imagery. It remained at this post until it was decommissioned on August 16, 2013 and subsequently boosted to a graveyard orbit.

GOES 13

GOES 13, known as GOES-N before becoming operational, is an American weather satellite which forms part of the US National Oceanic and Atmospheric Administration's Geostationary Operational Environmental Satellite system. On April 14, 2010, GOES-13 became the operational weather satellite for GOES-EAST. It was replaced by GOES-16 on December 18, 2017 and on January 8, 2018 its instruments were shut off and it began its three week drift to 60 degrees west longitude, arriving on January 31st.

GOES 14 American weather satellite

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. The spacecraft was built by Boeing and is based on the BSS-601 bus. It is the second of three GOES satellites to use the BSS-601 bus, after GOES 13, which was launched in May 2006.

Imagery

First Image from GOES 12 on 7 September 2001 Goes12 firstimage.png
First Image from GOES 12 on 7 September 2001

The SXI aboard GOES 12 is a Wolter Type I (Wolter telescope) 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 on the electromagnetic spectrum from 6 to 60 angstrom units (Å). [3] The imagery obtained by the XSI and XRS on GOES 12 allowed forecasters to see space phenomena such as coronal holes, whose geomagnetic and proton storms impact electrical grid systems on Earth as well as radio communications and satellite communications systems. [2] [3]

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.

Corona Aura of plasma that surrounds the Sun and other stars

A corona is an aura of plasma that surrounds the Sun and other stars. The Sun's corona extends millions of kilometres into outer space and is most easily seen during a total solar eclipse, but it is also observable with a coronagraph. The word corona is a Latin word meaning "crown", from the Ancient Greek κορώνη.

The electromagnetic spectrum is the range of frequencies of electromagnetic radiation and their respective wavelengths and photon energies.

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 instrumentation, the XSI and XRS and been permanently deactivated. [4]

X-ray form of electromagnetic radiation

X-rays make up X-radiation, a form of electromagnetic radiation. Most X-rays have a wavelength ranging from 0.01 to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz (3×1016 Hz to 3×1019 Hz) and energies in the range 100 eV to 100 keV. X-ray wavelengths are shorter than those of UV rays and typically longer than those of gamma rays. In many languages, X-radiation is referred to with terms meaning Röntgen radiation, after the German scientist Wilhelm Röntgen who discovered these on November 8, 1895, who usually is credited as its discoverer, and who named it X-radiation to signify an unknown type of radiation. Spelling of X-ray(s) in the English language includes the variants x-ray(s), xray(s), and X ray(s).

See also

2001 in spaceflight Wikimedia list article

This article outlines notable events occurring in 2001 in spaceflight, including major launches and EVAs.

Related Research Articles

Solar flare

A solar flare is a sudden flash of increased brightness on the Sun, usually observed near its surface and in close proximity to a sunspot group. Powerful flares are often, but not always, accompanied by a coronal mass ejection. Even the most powerful flares are barely detectable in the total solar irradiance.

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 magnetosphere, ionosphere, thermosphere, and exosphere. Space weather is distinct from but conceptually related to the terrestrial weather of the atmosphere of Earth. The term space weather was first used in the 1950s and came into common usage in the 1990s. Similar to terrestrial climatology, the long term patterns of space weather comprise space climate.

Geomagnetic storm temporary disturbance of the Earths magnetosphere caused by a disturbance in the interplanetary medium

A geomagnetic storm is a temporary disturbance of the Earth's magnetosphere caused by a solar wind shock wave and/or cloud of magnetic field that interacts with the Earth's magnetic field. The increase in the solar wind pressure initially compresses the magnetosphere. The solar wind's magnetic field interacts with the Earth's magnetic field and transfers an increased energy into the magnetosphere. Both interactions cause an increase in plasma movement through the magnetosphere and an increase in electric current in the magnetosphere and ionosphere.

Coronal mass ejection Significant release of plasma and magnetic field from the solar corona

A coronal mass ejection (CME) is a significant release of plasma and accompanying magnetic field from the solar corona. They often follow solar flares and are normally present during a solar prominence eruption. The plasma is released into the solar wind, and can be observed in coronagraph imagery.

Deep Space Climate Observatory American solar research spacecraft

Deep Space Climate Observatory is a NOAA space weather, space climate, and Earth observation satellite. It was launched by SpaceX on a Falcon 9 launch vehicle on February 11, 2015, from Cape Canaveral.

Space environment is a branch of astronautics, aerospace engineering and space physics that seeks to understand and address conditions existing in space that affect the design and operation of spacecraft. A related subject, space weather, deals with dynamic processes in the solar-terrestrial system that can give rise to effects on spacecraft, but that can also affect the atmosphere, ionosphere and geomagnetic field, giving rise to several other kinds of effects on human technologies.

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), located in Boulder, Colorado. SWPC continually monitors and forecasts Earth's space environment, providing solar-terrestrial information. SWPC is the official source of space weather alerts and warnings for the United States.

Suzaku (satellite) satellite

Suzaku was an X-ray astronomy satellite developed jointly by NASA's Goddard Space Flight Center and the Institute of Space and Aeronautical Science at JAXA to probe high energy X-ray sources, such as supernova explosions, black holes and galactic clusters. It was launched on 10 July 2005 aboard the M-V-6 rocket. After its successful launch, the satellite was renamed Suzaku after the mythical Vermilion bird of the South.

The Lockheed Martin Solar and Astrophysics Laboratory (LMSAL) is part of the Lockheed Martin Advanced Technology Center (ATC) that is known primarily for its scientific work in the field of solar physics, astronomy and space weather. The LMSAL team is part of Lockheed Martin Space Systems and has close affiliations with NASA and the solar physics group at Stanford University.

Solar cycle 24 solar cycle

Solar Cycle 24 is the 24th solar cycle since 1755, when extensive recording of solar sunspot activity began. It is the current solar cycle, and began in December 2008 with a smoothed minimum of 2.2. Activity was minimal until early 2010. It reached its maximum in April 2014 with a smoothed sunspot number of only 81.8, the lowest since the Dalton Minimum. Reversed polarity polar active sunspot regions in December 2016, April 2018, and November 2018 indicate that a transitional phase to solar cycle 25 is in process.

<i>Hitomi</i> (satellite) X-ray astronomy satellite launched on 17 February 2016

Hitomi, also known as ASTRO-H and New X-ray Telescope (NeXT), was an X-ray astronomy satellite commissioned by the Japan Aerospace Exploration Agency (JAXA) for studying extremely energetic processes in the Universe. The space observatory was designed to extend the research conducted by the Advanced Satellite for Cosmology and Astrophysics (ASCA) by investigating the hard X-ray band above 10 keV. The satellite was originally called New X-ray Telescope; at the time of launch it was called ASTRO-H. After it was placed in orbit and its solar panels deployed, it was renamed Hitomi. The new name refers to the pupil of an eye, and to a legend of a painting of four dragons, two of which were given eyes and flew into the sky, and two that were left eyeless and stayed as motionless art. The spacecraft was launched on 17 February 2016 and contact was lost on 26 March 2016, due to multiple incidents with the attitude control system leading to an uncontrolled spin rate and breakup of structurally weak elements.

Joint Polar Satellite System

The Joint Polar Satellite System (JPSS) is the latest generation of U.S. polar-orbiting, non-geosynchronous, environmental satellites. JPSS will provide the global environmental data used in numerical weather prediction models for forecasts, and scientific data used for climate monitoring. JPSS will aid in fulfilling the mission of the U.S. National Oceanic and Atmospheric Administration (NOAA), an agency of the Department of Commerce. Data and imagery obtained from the JPSS will increase timeliness and accuracy of public warnings and forecasts of climate and weather events, thus reducing the potential loss of human life and property and advancing the national economy. The JPSS is developed by the National Aeronautics and Space Administration (NASA) for the National Oceanic and Atmospheric Administration (NOAA), who is responsible for operation of JPSS. Three to five satellites are planned for the JPSS constellation of satellites. JPSS satellites will be flown, and the scientific data from JPSS will be processed, by the JPSS - Common Ground System (JPSS-CGS).

GOES-16 geosynchronous environmental satellite

GOES-16, formerly known as GOES-R before reaching geostationary orbit, is the first of the GOES-R series of Geostationary Operational Environmental Satellite (GOES) operated by NASA and the National Oceanic and Atmospheric Administration (NOAA). GOES-16 serves as the operational geostationary weather satellite in the GOES East position at 75.2°W, providing a view centered on the Americas. GOES-16 provides high spatial and temporal resolution imagery of the Earth through 16 spectral bands at visible and infrared wavelengths using its Advanced Baseline Imager (ABI). GOES-16's Geostationary Lightning Mapper (GLM) is the first operational lightning mapper flown in geostationary orbit. The spacecraft also includes four other scientific instruments for monitoring space weather and the Sun.

Halloween solar storms, 2003

The Halloween solar storms were a series of solar flares and coronal mass ejections that occurred from mid-October to early November 2003, peaking around October 28–29. This series of storms generated the largest solar flare ever recorded by the GOES system, modeled as strong as X45. Satellite-based systems and communications were affected, aircraft were advised to avoid high altitudes near the polar regions, and a one-hour-long power outage occurred in Sweden as a result of the solar activity. Aurorae were observed at latitudes as far south as Texas and the Mediterranean countries of Europe.

Solar cycle 25 is the upcoming and 25th solar cycle since 1755, when extensive recording of solar sunspot activity began. It is expected to begin in late 2019 and continue through 2030. The first Cycle 25 sunspot may have appeared in early April 2018 or even December 2016.

GOES-17 Geostationary Operational Environmental Satellite

GOES-17 is the second of the current generation of weather satellites operated by the National Oceanic and Atmospheric Administration (NOAA). The four satellites of the series will extend the availability of the GOES until 2036 for weather forecast and meteorology research. The satellite was built by Lockheed Martin, was based on the A2100A platform, and will have an expected useful life of 15 years. The satellite was launched on 1 March 2018 and reached geostationary orbit on 12 March 2018. In May 2018, during the satellite's testing phase after launch, a problem was discovered with its primary instrument, the Advanced Baseline Imager. GOES-17 became operational as GOES-West on 12 February 2019. GOES-17 is currently operating alongside GOES-15 but will replace it in July 2019.

NOAA-20

NOAA-20, designated JPSS-1 prior to launch, is the first of the United States National Oceanic and Atmospheric Administration's latest generation of U.S. polar-orbiting, non-geosynchronous, environmental satellites called the Joint Polar Satellite System. NOAA-20 was launched on November 18, 2017 and joined the Suomi National Polar-orbiting Partnership satellite in the same orbit. NOAA-20 operates about 50 minutes ahead of Suomi NPP, allowing important overlap in observational coverage. Circling the Earth from pole-to-pole, it crosses the equator about 14 times daily, providing full global coverage twice a day. This will give meteorologists information on "atmospheric temperature and moisture, clouds, sea-surface temperature, ocean color, sea ice cover, volcanic ash, and fire detection" so as to enhance weather forecasting including hurricane tracking, post-hurricane recovery by detailing storm damage and mapping of power outages.

References

  1. "GOES Solar X-ray Imager". NOAA/SWPC. Retrieved 2015-06-29.
  2. 1 2 "Environmental Satellite Readied to Detect Solar Storms". NASA/NOAA. 2003-01-30. Retrieved 2009-12-12.
  3. 1 2 "The GOES Solar X-ray Imager". NASA/Marshall Solar Physics. 2007-01-18. Retrieved 2009-12-12.
  4. "GOES SXI Operational Status (2007-08-24)". Space Weather Prediction Center(SWPC). 2007-08-24. Retrieved 2009-12-12.