September 10 – 16, 2021

Solar activity forecast for the period September 10 – 16, 2021

Issued: 2021 Sep 9 2100 UTC

Activity level from Sep 10 to Sep 13: mostly low
X-ray background flux (1.0-8.0 A): in the range A9.0-B7.0
Radio flux (10.7 cm): a fluctuation in the range 85-105 f.u.
Events: class C (0-12/day), class M (0-1/day), class X (0/period), proton (0/period)
Relative sunspot number (Ri): in the range 22-80

Activity level from Sep 14 to Sep 16: mostly low
X-ray background flux (1.0-8.0 A): in the range A7.0-B6.0
Radio flux (10.7 cm): a fluctuation in the range 80-100 f.u.
Events: class C (0-12/day), class M (0-1/day), class X (0/period), proton (0/period)
Relative sunspot number (Ri): in the range 11-70

Jozef Lesko
Roztoky Observatory, Slovak Republic
www.osveta.sk/n/11283/astronomia.html
e-mail: safor (at) protonmail.ch

Geomagnetic activity forecast for the period September 10 – 16, 2021

Issued: 2021 Sep 9 2130 UTC

Quiet to unsettled: Sep 14 – 16
Quiet to active: Sep 10 – 13

Jozef Lesko
Roztoky Observatory, Slovak Republic
www.osveta.sk/n/11283/astronomia.html
e-mail: safor (at) protonmail.ch