Lockheed Martin
Delivers Helioseismic And Magnetic Imager To Goddard Space Flight Center For
NASA's Solar Dynamics Observatory
(15 November 2007) The Helioseismic
and Magnetic Imager (HMI), an instrument for NASA's Solar Dynamics Observatory
(SDO), has been delivered to NASA's Goddard Spacecraft Center for integration
on SDO, which is scheduled to launch in December 2008.
The HMI
was designed in collaboration with Professor Philip Scherrer, HMI Principal
Investigator, and other scientists at Stanford University. The instrument was
built at the Solar and Astrophysics Laboratory of the Lockheed Martin Advanced
Technology Center (ATC) in Palo Alto.
"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 will
learn about the structure, temperature and flows in the solar
interior.
"This is a very satisfying milestone for us, as the delivery
of HMI for mounting on the SDO spacecraft brings us a big step closer to having
this spectacular instrument in space watching the Sun," said solar physicist --
and co-investigator on HMI -- Dr. Alan Title of the ATC. "HMI will provide us
with sonograms of the Sun that will show us sunspots and magnetic fields before
they appear on the visible surface. 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. The prediction of these violent solar events, how they
travel through the solar system and where they are likely to impact is one of
the key elements of the NASA's Living With a Star (LWS) program. It is also of
critical importance to the NASA Vision for Space Exploration, and a human
presence on the Moon.
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.
The SDO spacecraft will also be a flagship in the
Heliophysics Great Observatory, a series of missions designed to monitor the
Sun and the heliosphere. As humans venture outward from Earth to the Moon, Mars
and beyond their safety depends upon, at least in part, an ability to forecast
energetic events on the Sun. Because both people and planets constantly move
with respect to the Sun, it is also essential to understand how the energy
released by these solar events travels through the heliosphere in order to
properly access the impact on space travellers wherever they may be in the
solar system.
The Solar and Astrophysics Laboratory at the ATC has a
44-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
environmental satellite, 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 behaviour of the Sun
including its impacts on Earth and climate.
The ATC is the research and
development organisation of Lockheed Martin Space Systems Company (LMSSC).
LMSSC, a major operating unit of Lockheed Martin Corporation, designs,
develops, tests, manufactures and operates a full spectrum of
advanced-technology systems for national security, civil 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;
fleet ballistic missiles; and missile defence systems.
Headquartered in
Bethesda, Md., Lockheed Martin employs about 140,000 people world-wide and is
principally engaged in the research, design, development, manufacture,
integration and sustainment of advanced technology systems, products and
services. The corporation reported 2006 sales of US$ 39.6
billion.
(source: Lockheed Martin)
