# Ionospheric Weather at Two Starlink Launches during Two-Phase Geomagnetic Storms
###### Abstract  
The launch of a series of Starlink internet satellites on 3 February 2022 (S-36), and 7 July 2022 (S-49), coincided with the development of two-phase geomagnetic storms. The first launch S-36 took place in the middle of the moderate two-phase space weather storm, which induced significant technological consequences. After liftoff on 3 February at 18:13 UT, all Starlink satellites reached an initial altitude of 350 km in perigee and had to reach an altitude of \(\sim\)550 km after the maneuver. However, 38 of 49 launched spacecrafts did not reach the planned altitude, left orbit due to increased drag and reentered the atmosphere on 8 February. A geomagnetic storm on 3-4 February 2022 has increased the density of the neutral atmosphere up to 50%, increasing drag of the satellites and dooming most of them. The second launch of S-49 at 13:11 UT on 7 July 2022 was successful at the peak of the two-phase geomagnetic storms. The global ionospheric maps of the total electron content (GIM-TEC) have been used to produce the ionospheric weather GIM-W index maps and Global Electron Content (_GEC_). We observed a _GEC_ increment from 10 to 24% for the storm peak after the Starlink launch at both storms, accompanying the neutral density increase identified earlier. GIM-TEC maps are available with a lag (delay) of 1-2 days (real-time GIMs have a lag less than 15 min), so the GIMs forecast is required by the time of the launch. Comparisons of different GIMs forecast techniques are provided including the Center for Orbit Determination in Europe (CODE), Beijing (BADG and CASG) and IZMIRAN (JPRG) 1- and 2-day forecasts, and the Universitat Politecnica de Catalunya (UPC-ionSAT) forecast for 6, 12, 18, 24 and 48 h in advance. We present the results of the analysis of evolution of the ionospheric parameters during both events. The poor correspondence between observed and predicted GIM-TEC and _GEC_ confirms an urgent need for the industry-science awareness of now-casting/forecasting/accessibility of GIM-TECs during the space weather events. ionosphere; global electron content; GIM; forecast; Starlink satellite launch; geomagnetic storm 2023  
[PERSON],  
3 February at 18:13 UT, all Starlink satellites reached an initial altitude of 350 km in perigee and had to reach an altitude of \(\sim\)550 km after the maneuver. However, 38 of 49 launched spacecrafts did not reach the planned altitude, left orbit due to increased drag and reentered the atmosphere on 8 February. A geomagnetic storm on 3-4 February 2022 has increased the density of the neutral atmosphere up to 50%, increasing drag on the satellites and dooming most of them [2; 3; 4; 5; 6; 7; 8]. [PERSON] et al. [6] mentioned the E \(\times\) B convection lift of the ionospheric electrons and ions to higher altitudes causing the drag. At the same time, photoionization by solar UV and EUV radiation replaces the depleted lower-altitude ions, giving an overall increase in \(TEC\) on the dayside. To compare the ionospheric effects for the S-36 launch with another similar event, we considered the second launch of S-49 at 13:11 UT on 7 July 2022, which was successful at the peak of the two-phase geomagnetic storm. The global ionosphere maps of total electron content (GIM-TEC) are used in the present study for the analysis of the ionospheric weather during two Starlink launches. GIM-TEC maps are available with a lag (delay) of 1-2 days, and the real-time GIMs have a lag of 15 min [9]. Hence, the GIMs forecast is required in any case by the time of any satellite launch, because the 'true' GIMs are produced only for the time prior to the launch. The goal of the present study was the evaluation of the performance of the different forecast GIMs during the two Starlink launches. The Jet Propulsion Laboratory (JPL)-produced GIM-TEC maps [10] are routinely used to calculate the ionospheric weather GIM-W index maps [11]. W index represents the logarithmic deviation of instantaneous \(TEC\) from the preceding 15-day sliding median TEC\(\upmu\) at the same hour UT for each cell of GIM.