PRESTO ALERT

:Issued: 2026 Sep 14 0851 UTC
:Product: documentation at http://www.sidc.be/products/presto
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# FAST WARNING 'PRESTO' MESSAGE  from the SIDC (RWC-Belgium)         #
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A weak shock was detected in the L1 solar wind at 02:25 UT on 14 September.
The interplanetary magnetic field jumped from 4 to 8 nT, the solar wind
speed from 260 to 350 km/s and its density from 1 to 4 particles per cubic
centimeter. The origin is still being investigated, but could be related to
a glancing blow from a CME leaving the Sun on 9-10 September. There has not
been any significant geomagnetic disturbance associated with it up to now,
and probably none will occur.
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# Solar Influences Data analysis Center - RWC Belgium                #
# Royal Observatory of Belgium                                       #
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