SFI = 166
A index = 5
K index = 1
SSN = 166
GEOMAGNETIC STORM WATCH: Minor G1-class geomagnetic storms are possible on July 20th or 21st when a slow-moving CME is expected to hit Earth’s magnetic field. The CME was hurled into space by an unstable filament of magnetism, which erupted on July 15th.
HUGE SOLAR PROMINENCE MIGHT BE COMING APART: For days, astronomers have been monitoring a huge prominence on the sun. It might be coming apart. On Saturday, July 16th, Dr. Sebastian Voltmer watched part of the structure fly away:
“The sheer size of the prominence is impressive,” says Voltmer. “It was spectacular to see a very fast moving part of it ejecting and detaching to the side.” Voltmer watched the action through a small refracting telescope protected by a Daystar Quark filter system.
Structures like this, in which hot plasma is held above the sun’s surface by dynamic magnetic fields, are inherently unstable. The entire prominence could come down at any moment. If it falls today, amateur astronomers will get a fantastic side-on view of its disintegration.
NOAA STI
:Product: Geophysical Alert Message wwv.txt
:Issued: 2022 Jul 18 0910 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
#
# Geophysical Alert Message
#
Solar-terrestrial indices for 17 July follow.
Solar flux 166 and estimated planetary A-index 5.
The estimated planetary K-index at 0900 UTC on 18 July was 2.
No space weather storms were observed for the past 24 hours.
No space weather storms are predicted for the next 24 hours.
NOAA Alerts
Space Weather Message Code: ALTEF3
Serial Number: 3260
Issue Time: 2022 Jul 18 0500 UTC
CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Continuation of Serial Number: 3259
Begin Time: 2022 Jul 16 1025 UTC
Yesterday Maximum 2MeV Flux: 5273 pfu
NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation
Potential Impacts: Satellite systems may experience significant charging resulting in increased risk to satellite systems.