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By Daniel Guevarra |
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February 12, 2010
- Two state-of-the art solar instruments built at the Solar and
Astrophysics Laboratory of the Lockheed Martin Advanced Technology
Center (ATC) in Taking
images that span at least 1.3 solar diameters in multiple wavelengths
nearly simultaneously, at a resolution of about one arc-second and at a
cadence of ten seconds or better. The Helioseismic and Magnetic Imager
(HMI), designed in collaboration with Professor Philip Scherrer, HMI
Principal Investigator, and other scientists at |
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“The successful launch is a very significant step for the solar physics community. With AIA now in space we’re getting very close to the time when this instrument will be providing the kind of data we need to unravel mysteries of the Sun that have been just beyond our grasp,” said physicist – and Principal Investigator of AIA – Dr. Alan Title of the ATC. “Looking at the full Sun in a broad range of temperature bands every 10 seconds will give us unprecedented insight into the processes that determine the evolution of the corona.”
The AIA will produce data required for quantitative studies of the
evolving coronal magnetic field, and the plasma it holds, both in
quiescent phases and during flares and eruptions. The primary goal of
the AIA Science Investigation is to use these data, together with data
from other SDO instruments and from other observatories, to
significantly improve our understanding of the physics behind the
activity displayed by the Sun's atmosphere, which drives space weather
in the heliosphere and in planetary environments. Ultimately, it is
hoped that the greater understanding gained of the observed processes
will guide development of advanced forecasting tools needed by the user
community of the Living With a Star (LWS) program.
"HMI combined with our partner instruments on SDO – the Atmospheric
Imaging Assembly and the Extreme Ultraviolet Variability Experiment –
will provide us with the data needed to first learn if predictions of
solar activity are possible,” said Professor Scherrer. “Then, if we and
our colleagues in the solar physics community are clever enough, we’ll
actually develop forecast methods. This is an exciting time for studying
the Sun and its impact on the Earth." |
The primary goal
of the HMI investigation on SDO is to study the origin of solar
variability and to characterize and understand the Sun’s interior and
magnetic activity. Because of the turbulence in the convection zone near
the surface, the Sun is figuratively ringing like a bell. By studying
these oscillations of the visible surface of the Sun, considerable
insight can be gained into the processes inside. In effect the solar
turbulence is analogous to earthquakes. In manner similar to how
seismologists can learn about the interior of the Earth by studying the
waves generated in an earthquake. HMI’s helioseismologists learn about
the structure, temperature and flows in the solar interior.
“HMI will provide
us with sonograms of the Sun that will show us sunspots and magnetic
fields before they appear on the visible surface,” added Dr. Alan Title
– co-investigator on HMI. “We’ll even be able to see through the Sun and
be aware of the birth of spots on the side facing away from us, allowing
us to be ready for them as they rotate into our view. Moreover, HMI’s
high spatial resolution and full-Sun coverage will give us much more
time to study magnetic field evolution in detail.”
HMI will produce
data necessary 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. Because HMI can measure the
strength and direction of the magnetic field on the surface, more
precise estimates of the coronal magnetic field are possible. In
addition, HMI observations will clarify the relationships between
internal solar dynamics and magnetic activity, providing a better
understanding of solar variability and its effects. The knowledge gained
will enable a major advance in the development of a reliable predictive
capability for solar flares and coronal mass ejections.
Solar scientists
will use the third instrument on SDO – the Extreme Ultraviolet
Variability Experiment (EVE) – to measure the Sun’s brightness in the
most variable and unpredictable part of the solar spectrum. The extreme
ultraviolet, or EUV, ranges in wavelength from 0.1 to 105 nm. EVE will
collect spectra over a broad EUV to UV range from the entire Sun. EVE
and AIA will be able together to establish how local events like flares
affect the entire solar spectrum.
The goal of SDO is
to understand – striving towards a predictive capability – the solar
variations that influence life on Earth and humanity’s technological
systems. The mission seeks to determine how the Sun’s magnetic field is
generated and structured, and how this stored magnetic energy is
converted and released into the heliosphere and geospace in the form of
solar wind, energetic particles, and variations in the solar irradiance.
Flying in a
geosynchronous orbit, SDO will observe the Sun 24 hours a day without
interruption, and downlink its data to the
SDO is the most
advanced spacecraft ever designed to study the Sun and its dynamic
behavior. SDO will provide better quality, more comprehensive science
data faster than any NASA spacecraft currently studying the Sun and its
processes. SDO will unlock the secrets of how our nearest star sustains
life on Earth, affects the planets of our solar system and beyond.
SDO is the first
mission and crown jewel in a fleet of NASA missions to study our Sun.
The mission is the cornerstone of a NASA science program called Living
With a Star (LWS). The goal of the LWS Program is to develop the
scientific understanding necessary to address those aspects of the Sun
and solar system that directly affect life and society.
SDO will study how
solar activity is created and how space weather results from that
activity. Measurements of the Sun’s interior, magnetic field, the hot
plasma of the solar corona, and the irradiance will help meet the
objectives of the SDO mission. SDO is managed by NASA’s Goddard Space
Flight Center for the agency’s Science Mission Directorate at NASA
Headquarters in
The Solar and
Astrophysics Laboratory at the ATC has a 47-year-long heritage of
spaceborne solar instruments including the Soft X-ray Telescope on the
Japanese Yohkoh satellite, the Michelson Doppler Imager on the ESA/NASA
Solar and Heliospheric Observatory, the solar telescope on NASA’s
Transition Region and Coronal Explorer, the Solar X-ray Imager on the
GOES-N and O environmental satellites, the Focal Plane Package on Hinode
and an Extreme Ultraviolet Imager on each of the two spacecraft in
NASA’s Solar Terrestrial Relations Observatory. The laboratory also
conducts basic research into understanding and predicting space weather
and the behavior of the Sun including its impacts on Earth and climate.
The ATC is the
research and development organization of Lockheed Martin Space Systems
Company (LMSSC). LMSSC, a major operating unit of Lockheed Martin
Corporation, designs and develops, tests, manufactures and operates a
full spectrum of advanced-technology systems for national security and
military, civil government and commercial customers. Chief products
include human space flight systems; a full range of remote sensing,
navigation, meteorological and communications satellites and
instruments; space observatories and interplanetary spacecraft; laser
radar; ballistic missiles; missile defense systems; and nanotechnology
research and development.
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