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Post Info TOPIC: Sun 26.04.07


L

Posts: 131433
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RE: Sun 26.04.07
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Title: Three dimensional structure of penumbral filaments from Hinode observations
Authors: K.G. Puschmann, B. Ruiz Cobo, V. Martinez Pillet

We analyse spectropolarimetric observations of the penumbra of the NOAA AR 10953 at high spatial resolution (0.3"). The full Stokes profiles of the Fe I lines at 630.1 nm and 630.2 nm have been obtained with the Solar Optical Telescope (SOT) on board the Hinode satellite. The data have been inverted by means of the SIR code, deriving the stratifications of temperature, line of sight velocity, and the components of the magnetic field vector in optical depth. In order to evaluate the gas pressure and to obtain an adequate geometrical height scale, the motion equation has been integrated for each pixel taking into account the terms of the Lorentz force. To establish the boundary condition, a genetic algorithm has been applied. The final resulting magnetic field has a divergence compatible with 0 inside its uncertainties. First analyses of the correlation of the Wilson depression with velocity, temperature, magnetic field strength, and field inclination strongly support the uncombed penumbral model proposed by Solanki & Montavon (1993).

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L

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Sunspot 10953
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5 day animation of Sunspot 10953



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L

Posts: 131433
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RE: Sun 26.04.07
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After what seemed to be a unusually long period without  any notable sunspot activity. A  large new sunspot has emerged from  the Suns eastern limb.

Joint USAF/NOAA Report of Solar and Geophysical Activity SDF Number 116 Issued at 2200Z on 26 Apr 2007

IA.  Analysis of Solar Active Regions and Activity from  25/2100Z to 26/2100Z:  Solar activity was very low.  Region 953 (S10E61) produced only B-class activity during the past 24 hours.

IB.  Solar Activity Forecast:  Solar activity is expected to be very low to low.

IIA.  Geophysical Activity Summary 25/2100Z to 26/2100Z: The geomagnetic field has been quiet to unsettled.

IIB.  Geophysical Activity Forecast:  The geomagnetic field is expected to be quiet to unsettled on 27 April.  A recurrent coronal hole high speed stream is expected to become geoeffective on 28 April.  Expect unsettled to minor storm conditions on 28 - 29 April.

III.  Event Probabilities 27 Apr-29 Apr
Class M    05/05/05
Class X    01/01/01
Proton     01/01/01
PCAF       Green

IV.  Penticton 10.7 cm Flux
Observed           26 Apr 081
Predicted   27 Apr-29 Apr  080/080/080
90 Day Mean        26 Apr 074

V.  Geomagnetic A Indices
Observed Afr/Ap 25 Apr  004/005
Estimated Afr/Ap 26 Apr  005/005
Predicted Afr/Ap 27 Apr-29 Apr  005/005-015/025-015/015

VI.  Geomagnetic Activity Probabilities 27 Apr-29 Apr
A.  Middle Latitudes
Active                10/30/30
Minor storm           01/20/20
Major-severe storm    01/05/05
B.  High Latitudes
Active                10/40/35
Minor storm           05/25/20
Major-severe storm    01/10/05


Source

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L

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Sunspot 10953 has emerged from the Suns eastern limb.

Sun 26.04.07
Expand (110kb, 560 x 560)

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