Water Production of Comet C1999 S4 LINEAR

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Water Production of Comet
C/1999 S4 (LINEAR)

• SWAN observed hydrogen coma of comet C/1999 S4
  from end of May through mid August 2000
• Obtained systematic set of water production rates
  for this well documented event of complete
  fragmentation of a cometary nucleus.
• Total amount of water released 3.3x109 kg
• Combining the SWAN measurements with Hubble
  observations of the last fragements yields
  estimate for size of comet r 375 m
• and thus estimate of density ? 15
  kg/m3

SWAN observations of Comet LINEAR a month before
it disintegrated.
Fragments of Comet Linear seen as mini-comets by
HST on 5 August 2000.
Mäkinen et al. 2001, Science 292, 1326
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UV/EUV Spectral Atlas 670 1609Å

• Best ever analysis of the ultraviolet spectrum of
  the Sun from 670 to 1609 Å
• 1100 emission lines identified
• 150 of these had not been recorded or identified
  before
• Particular improvement for ??????Å
• Atlas contains spectra of the quiet Sun, a
  coronal hole, and a sunspot.
• Rich source of new diagnostic tools to study
  physical parameters in the solar atmosphere.
• Important product both for solar and stellar
  communities.

Curdt et al. 2001, AA 375, 591
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Synoptic Imaging of the
Far Side of the Sun

• Synoptic maps combining observed magnetic flux
  from the near-side of the Sun with proxy flux
  from the far-side inferred from sound travel time
  analysis
• Data medium-l MDI data
• Technique two-skip helioseismic holography
  (Lindsey Braun, Science 2000)
• Updated daily on Internet

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The Event of 24 September 20014th Largest
Proton Storm of the Current Solar Cycle