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LIVING WITH A STAR PROGRAM
We live in the extended atmosphere of an active star. While sunlight enables
and sustains life, the Sun's variability produces streams of high-energy
particles and radiation that can affect life.
Under the protective shield of its the magnetic field and atmosphere,
the Earth is an island in the solar system where life has developed and
flourished. The origins and fate of life on Earth are intimately connected
to the way the Earth responds to the Sun's variations. Understanding the
changing Sun and its effects on the Solar System, life, and society is
the goal of the Sun-Earth Connection Theme.
There are two groups of mission spacecraft in the LWS Space Weather Research
Network:
(a) Solar dynamics elements (Solar Dynamics Observatory/Sentinels)
that observe the Sun, track the disturbances originating
there through the heliosphere, and
(b) Geospace dynamics elements (Geospace Missions Network)
consisting of spacecraft located in the magnetosphere and
ionosphere to define the Geospace response to varying solar
and solar wind input.
WHAT IS "SPACE WEATHER"?
Everyone is familiar with changes in the weather on Earth. But "weather" also
occurs in space. Just as it drives weather on Earth, the Sun is responsible
for disturbances in our space environment.
Besides emitting a continuous stream of plasma called the solar wind,
the Sun periodically releases billions of tons of matter in what are called
coronal mass ejections. These immense clouds of material, when directed
towards Earth, can cause large magnetic storms in the magnetosphere and
the upper atmosphere.
The term space weather generally refers to conditions on the Sun and
in the solar wind, magnetosphere, ionosphere, and thermosphere that can
influence the performance and reliability of space-borne and ground-based
technological systems and can endanger human life or health.
STORMS IN SPACE
Magnetic storms produce many noticeable effects on and near Earth:
- Aurora borealis, the northern lights, and aurora australis,
the southern lights
- Communication disruptions
- Radiation hazards to orbiting astronauts and spacecraft
- Current surges in power lines
- Orbital degradation
- Corrosion in oil pipelines
THE SUN AND EARTH ARE A CONNECTED SYSTEM
Variable Star |
Varying |
Earth |
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- Radiation
- Solar Wind Plasma and Magnetic fields
- Energetic Particles
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Interacting |
Interacting |
Interacting |
- Magnetic Fields
- Plasmas
- Energetic Particles
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- Solar Wind Plasma and Magnetic Fields
- Energetic Particles
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- Magnetic Fields
- Atmosphere
- Plasmas
- Radiation Belt-Energetic Particles
- Ionosphere/Thermosphere
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