Information about Solar-B
The Science of Solar-B
EIS Science Planning Guide
Solar-B EIS Contacts
Solar-B Links
EIS working page
Mullard Space Science Laboratory
Solar-B Science
The Sun is our nearest star. Its proximity provides heat and light to maintain life on Earth, as well as a unique laboratory to test our theories of stellar evolution and galaxy formation.It is crucial for our survival on Earth to understand the Sun's effect on the near-earth environment and on the climate of the earth. Our ability to resolve features on the Sun and study the physical processes occurring in detail helps us to understand the processes occurring on other stars and astrophysical objects. In turn, improving our understanding of other stars gives us information on the long-term evolution of the Sun.
The Solar-B mission will provide us with the opportunity to bettter understand that aspect of the Sun that affects the climate on Earth and space weather: solar activity.
The major science goals of Solar-B are:
To determine the mechanisms responsible for heating the corona in active
regions and the quiet Sun.
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One of the remaining unresolved questions in solar physics is why the
temperature of the atmosphere rises from 5780 K at the photosphere to
millions K in the corona. Clearly the second law of thermodynamics
tells us that the temperature should fall as you move away from a heat
source (at the core of the Sun).
The fact that this happens only until we reach the photosphere suggests that an additional non-thermal heat source is needed to explain and maintain the high temperatures seen in the corona. Several mechanisms have been suggested and we are confident that the energy must come from the magnetic field. However, there is as yet no consensus on the details. Solar-B will be able to determine the physical mechanisms responsible for coronal heating using a combination of spectroscopic and magnetic information to determine how the magnetic energy is converted in the EUV and X-ray radiation we see in the corona. |
To determine the mechanisms responsible for transient phenomena, such as
flares and coronal mass ejections.
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Flares and coronal mass ejections (CMEs) are the most energetic
manifestations of our Sun's activity and the most likely to directly affect
our environment on Earth. CMEs in particular when headed in our direction can
cause major magnetic disturbances when they reach the Earth's magnetopshere.
The causes of these explosions and expulsions of plasma are not yet fully
understood.
Solar-B will provide measurements of magnetic fields, electric currents and velocity fields, which coupled with imaging of the corona will reveal the trigger for both flares and CMEs. With an understanding of what triggers these events our opportunities for reliable prediction increase substantially. |
To investigate the processes responsible for energy transfer from the
photosphere to the corona.
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The energy to maintain the high temperatures of the transition region and
corona, and for flares, CMEs and smaller scale activity observed in these
parts of the atmosphere must come from the magnetic field which originates
below the Sun's convection zone.
To determine how this energy is transferred from below the photosphere up to outer atmosphere we need to be able simultaneously measure changes in the magnetic field with the transition region and coronal response. With Solar-B we will be able to make this connection and understand how the energy is transferred. |