EVE FOV and HMI/AIA Flatfield calibration maneuvers, July 21, 2021 [Archive]

ExomatrixTV

4th August 2021, 19:30

The Solar Dynamics Observatory (SDO) is a NASA (https://en.wikipedia.org/wiki/NASA) mission which has been observing the Sun (https://en.wikipedia.org/wiki/Sun) since 2010. Launched on 11 February 2010, the observatory is part of the Living With a Star (https://en.wikipedia.org/wiki/Living_With_a_Star) (LWS) program.

The goal of the LWS program is to develop the scientific understanding necessary to effectively address those aspects of the connected Sun (https://en.wikipedia.org/wiki/Sun)–Earth (https://en.wikipedia.org/wiki/Earth) system directly affecting life and society. The goal of the SDO is to understand the influence of the Sun on the Earth and near-Earth space by studying the solar atmosphere on small scales of space and time and in many wavelengths simultaneously. SDO has been investigating how the Sun's magnetic field (https://en.wikipedia.org/wiki/Stellar_magnetic_field) is generated and structured, how this stored magnetic energy is converted and released into the heliosphere (https://en.wikipedia.org/wiki/Heliosphere) and geospace (https://en.wikipedia.org/wiki/Geospace) in the form of solar wind (https://en.wikipedia.org/wiki/Solar_wind), energetic particles, and variations in the solar irradiance (https://en.wikipedia.org/wiki/Solar_irradiance).

The SDO spacecraft was developed at NASA's Goddard Space Flight Center (https://en.wikipedia.org/wiki/Goddard_Space_Flight_Center) in Greenbelt, Maryland (https://en.wikipedia.org/wiki/Greenbelt,_Maryland), and launched on 11 February 2010, from Cape Canaveral Air Force Station (CCAFS (https://en.wikipedia.org/wiki/Cape_Canaveral_Space_Force_Station)). The primary mission lasted five years and three months, with expendables expected to last at least ten years. Some consider SDO to be a follow-on mission to the Solar and Heliospheric Observatory (https://en.wikipedia.org/wiki/Solar_and_Heliospheric_Observatory) (SOHO).

SDO is a three-axis stabilized spacecraft (https://en.wikipedia.org/wiki/Attitude_control), with two solar arrays (https://en.wikipedia.org/wiki/Solar_panel), and two high-gain antennas, in an inclined geosynchronous orbit (https://en.wikipedia.org/wiki/Geosynchronous_orbit) around Earth (https://en.wikipedia.org/wiki/Earth).
The spacecraft includes three instruments:

the Extreme Ultraviolet Variability Experiment (EVE) built in partnership with the University of Colorado Boulder (https://en.wikipedia.org/wiki/University_of_Colorado_Boulder)'s Laboratory for Atmospheric and Space Physics (https://en.wikipedia.org/wiki/Laboratory_for_Atmospheric_and_Space_Physics) (LASP),
the Helioseismic and Magnetic Imager (HMI) built in partnership with Stanford University (https://en.wikipedia.org/wiki/Stanford_University), and
the Atmospheric Imaging Assembly (AIA) built in partnership with the Lockheed Martin Solar and Astrophysics Laboratory (https://en.wikipedia.org/wiki/Lockheed_Martin_Solar_and_Astrophysics_Laboratory) (LMSAL).

Data which is collected by the craft is made available as soon as possible, after it is received. As of February 2020, SDO is expected to remain operational until 2030.

Helioseismic and Magnetic Imager (HMI)

https://upload.wikimedia.org/wikipedia/commons/thumb/d/d7/Getting_NASA%27s_SDO_into_Focus.jpg/220px-Getting_NASA%27s_SDO_into_Focus.jpg (https://en.wikipedia.org/wiki/File:Getting_NASA%27s_SDO_into_Focus.jpg)
Comparison of HMI Continuum

immediately after an eclipse (https://en.wikipedia.org/wiki/Eclipse), and then after the sensor has rewarmed.

The Helioseismic (https://en.wikipedia.org/wiki/Helioseismology) and Magnetic Imager (HMI), led from Stanford University (https://en.wikipedia.org/wiki/Stanford_University) in Stanford, California (https://en.wikipedia.org/wiki/Stanford,_California), studies solar variability and characterizes the Sun's interior and the various components of magnetic activity. HMI will take high-resolution measurements of the longitudinal and vector magnetic field over the entire visible solar disk thus extending the capabilities of SOHO (https://en.wikipedia.org/wiki/Solar_and_Heliospheric_Observatory)'s MDI instrument.

HMI produces data to determine the interior sources and mechanisms of solar variability and how the physical processes inside the Sun are related to surface magnetic field and activity. It also produces data to enable estimates of the coronal magnetic field for studies of variability in the extended solar atmosphere. HMI observations will enable establishing the relationships between the internal dynamics and magnetic activity in order to understand solar variability and its effects.

Extreme Ultraviolet Variability Experiment (EVE)

The Extreme Ultraviolet Variability Experiment (EVE) measures the Sun (https://en.wikipedia.org/wiki/Sun)'s extreme ultraviolet (https://en.wikipedia.org/wiki/Extreme_ultraviolet) irradiance with improved spectral resolution (https://en.wikipedia.org/wiki/Spectral_resolution), "temporal cadence", accuracy, and precision over preceding measurements made by TIMED (https://en.wikipedia.org/wiki/TIMED) SEE, SOHO (https://en.wikipedia.org/wiki/Solar_and_Heliospheric_Observatory), and SORCE (https://en.wikipedia.org/wiki/Solar_Radiation_and_Climate_Experiment) XPS (https://en.wikipedia.org/wiki/X-ray_photoelectron_spectroscopy). The instrument incorporates physics-based models in order to further scientific understanding of the relationship between solar EUV (https://en.wikipedia.org/wiki/Extreme_ultraviolet) variations and magnetic variation changes in the Sun.

The Sun's output of energetic extreme ultraviolet photons (https://en.wikipedia.org/wiki/Photon) is primarily what heats the Earth (https://en.wikipedia.org/wiki/Earth)'s upper atmosphere (https://en.wikipedia.org/wiki/Mesosphere) and creates the ionosphere (https://en.wikipedia.org/wiki/Ionosphere). Solar EUV radiation (https://en.wikipedia.org/wiki/Radiation) output undergoes constant changes, both moment to moment and over the Sun's 11-year solar cycle (https://en.wikipedia.org/wiki/Solar_cycle), and these changes are important to understand because they have a significant impact on atmospheric heating (https://en.wikipedia.org/wiki/Atmospheric_physics), satellite drag (https://en.wikipedia.org/wiki/Drag_(physics)), and communications (https://en.wikipedia.org/wiki/Communication) system degradation, including disruption of the Global Positioning System (https://en.wikipedia.org/wiki/Global_Positioning_System).

The EVE instrument package was built by the University of Colorado Boulder (https://en.wikipedia.org/wiki/University_of_Colorado_Boulder)'s Laboratory for Atmospheric and Space Physics (https://en.wikipedia.org/wiki/Laboratory_for_Atmospheric_and_Space_Physics) (LASP), with Dr. Tom Woods as principal investigator (https://en.wikipedia.org/wiki/Principal_investigator), and was delivered to NASA Goddard Space Flight Center (https://en.wikipedia.org/wiki/Goddard_Space_Flight_Center) on 7 September 2007. The instrument provides improvements of up to 70% in spectral resolution measurements in the wavelengths below 30 nm, and a 30% improvement in "time cadence" by taking measurements every 10 seconds over a 100% duty cycle (https://en.wikipedia.org/wiki/Duty_cycle).

Atmospheric Imaging Assembly (AIA)

The Atmospheric Imaging Assembly (AIA), led from the Lockheed Martin Solar and Astrophysics Laboratory (https://en.wikipedia.org/wiki/Lockheed_Martin_Solar_and_Astrophysics_Laboratory) (LMSAL), provides continuous full-disk observations of the solar chromosphere (https://en.wikipedia.org/wiki/Chromosphere) and corona (https://en.wikipedia.org/wiki/Solar_corona) in seven extreme ultraviolet (https://en.wikipedia.org/wiki/Extreme_ultraviolet) (EUV) channels, spanning a temperature range from approximately 20,000 Kelvin to in excess of 20 million Kelvin. The 12-second cadence of the image stream with 4096 by 4096 pixel images at 0.6 arcsec/pixel provides unprecedented views of the various phenomena that occur within the evolving solar outer atmosphere.

The AIA science investigation is led by LMSAL, which also operates the instrument and – jointly with Stanford University – runs the Joint Science Operations Center from which all of the data are served to the worldwide scientific community, as well as the general public. LMSAL designed the overall instrumentation and led its development and integration. The four telescopes providing the individual light feeds for the instrument were designed and built at the Smithsonian Astrophysical Observatory (https://en.wikipedia.org/wiki/Smithsonian_Astrophysical_Observatory) (SAO). Since beginning its operational phase on 1 May 2010, AIA has operated successfully with unprecedented EUV image quality.

source (https://en.wikipedia.org/wiki/Solar_Dynamics_Observatory)