Viewing archive of Thursday, 16 December 1999
Geophysical report
Any mentioned solar flare in this report has a scaling factor applied by the Space Weather Prediction Center (SWPC). Because of the SWPC scaling factor, solar flares are reported as 42% smaller than for the science quality data. The scaling factor has been removed from our archived solar flare data to reflect the true physical units.
Solar and Geophysical Activity Summary 1999 Dec 16 0245 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Solar and Geophysical Activity Summary
SGAS Number 350 Issued at 0245Z on 16 DEC 1999 This report is compiled from data received at SWO on 15 DECA. Energetic Events
Begin Max End Rgn Loc Xray Op 245MHz 10cm Sweep 0157 0157 0202 250 0307 0318 0328 8798 S15E61 SF 130
B. Proton Events
None.
C. Geomagnetic Activity Summary
THE GEOMAGNETIC FIELD WAS QUIET TO
UNSETTLED.
D. Stratwarm
None.
E. Daily Indices: (real-time preliminary/estimated values)
10 CM 179 SSN 148 AFR/AP 002/004 X-RAY BACKGROUND B7.2 DAILY PROTON FLUENCE (FLUX ACCUMULATION OVER 24 HRS) GT 1 MEV 3.4E+04 GT 10 MEV 1.1E+04 P/(CM2-STER-DAY) (GOES-8 SATELLITE SYNCHRONOUS ORBIT W75 DEGREES) DAILY ELECTRON FLUENCE GT 2 MEV 1.30E+05 E/(CM2-STER-DAY) (GOES-8 SATELLITE SYNCHRONOUS ORBIT W75 DEGREES) 3 HOUR K-INDICES: BOULDER 0 0 0 0 0 1 2 2 PLANETARY 0 0 0 0 1 1 1 3
F. Comments
None.
All times in UTC
Latest news
Sunday, 7 December 2025
M8.1 solar flare with earth-directed CME
Monday, 1 December 2025
X1.9 solar flare, Coronal hole faces Earth
Friday, 14 November 2025
X4.0 solar flare
Latest forum messages
Light pillar 4AR4299 M8.1 CME 2025/12/06 268AR 4299 153Geomagnetic Data / Monitoring 6AR4294 / 4296 / 4298 437
More topicsSupport SpaceWeatherLive.com!
A lot of people come to SpaceWeatherLive to follow the Solar activity or if there is a chance to see the aurora, but with more traffic comes higher costs to keep the servers online. If you like SpaceWeatherLive and want to support the project you can choose a subscription for an ad-free site or consider a donation. With your help we can keep SpaceWeatherLive online!
Space weather facts
| Last X-flare | 2025/12/08 | X1.1 |
| Last M-flare | 2025/12/09 | M1.5 |
| Last geomagnetic storm | 2025/12/04 | Kp5 (G1) |
| Spotless days | |
|---|---|
| Last spotless day | 2022/06/08 |
| Monthly mean Sunspot Number | |
|---|---|
| November 2025 | 91.8 -22.8 |
| December 2025 | 160.6 +68.8 |
| Last 30 days | 108.7 +12.8 |