CIR IMPACT SPARKS BRIGHT AURORAS: A co-rotating interaction region (CIR) hit Earth's magnetic field on Jan. 8th, igniting some of the best Arctic auroras in years. Lights over Lapland tour guide Sachrias Rundquist sends this picture from Abisko, Sweden.

SUBSIDING GEOMAGNETIC STORM: A G1-class geomagnetic storm caused by the impact of a CIR on Jan. 8th (see above) is subsiding now. The storm is over. Arctic auroras remain possible as Earth enters a moderately fast stream of solar wind flowing behind the CIR.

Solar wind
speed: 444.6 km/sec
density: 4.9 protons/cm3
Updated: Today at 1555 UT

X-ray Solar Flares
6-hr max: B4 1318 UT Jan10
24-hr: B5 1602 UT Jan09
Updated: Today at: 1600 UT

Daily Sun: 10 Jan 22

All of these sunspots have stable magnetic fields that pose little threat for strong flares. Credit: SDO/HMI

Planetary K-index
Now: Kp= 1 quiet
24-hr max: Kp= 3 quiet

Interplanetary Mag. Field
Btotal: 3.7 nT
Bz: -2.7 nT south
Updated: Today at 1555 UT

Coronal Holes: 10 Jan 22

Solar wind flowing from this emerging coronal hole should reach Earth on Jan 17-18. Credit: SDO/AIA

FARSIDE SOLAR EXPLOSION: Something just exploded on the farside of the sun. Hidden from view, the blast hurled a magnificent CME over the northeastern edge of the solar disk. The bright light at the top of this SOHO coronagraph movie is Venus, which happened to be passing by the sun at the same time:

When the CME appeared, US Air Force antennas detected strong Type II and Type IV radio bursts. These are caused by shock waves inside the CME. Frequency drifts revealed the speed of the storm cloud, approximately 575 km/s or 1.3 million mph.

The source of this blast, probably an unstable sunspot, should turn toward Earth later this week.

Solar wind
speed: 392.2 km/sec
density: 6.6 protons/cm3
Updated: Today at 1606 UT

X-ray Solar Flares
6-hr max: B4 1147 UT Jan11
24-hr: C1 0838 UT Jan11
Updated: Today at: 1610 UT

Daily Sun: 11 Jan 22

All of these sunspots have stable magnetic fields that pose little threat for strong flares. Credit: SDO/HMI

Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 2 quiet

Interplanetary Mag. Field
Btotal: 6.1 nT
Bz: -3.0 nT south
Updated: Today at 1605 UT

Coronal Holes: 11 Jan 22

Solar wind flowing from this southern coronal hole should reach Earth on Jan 16-17. Credit: SDO/AIA

THE FORECAST CALLS FOR QUIET: Earth is in a void between solar wind streams. Quiet conditions are expected to prevail until the next stream arrives on Jan. 16th or 17th. This forecast could be upended by a solar flare. The sun is dotted with 3 numbered sunspot groups; unexpected explosions could occur at any time.

THE MORNING STAR IS BACK: On Saturday, Jan. 8th, Venus passed by the sun, moving from the evening to the morning sky. Paolo Bardelli woke up early this morning in Sumirago (Varese), Italy, and made a discovery: "Venus is back!"

Solar wind
speed: 510.8 km/sec
density: 5.3 protons/cm3
more data: ACE, DSCOVR
Updated: Today at 1511 UT

X-ray Solar Flares
6-hr max: C2 1142 UT Jan13
24-hr: C2 1142 UT Jan13
explanation | more data
Updated: Today at: 1515 UT

GEOMAGNETIC STORM WATCH: Minor G1-class geomagnetic storms are possible on Jan. 16th when a stream of high-speed solar wind is expected to hit Earth's magnetic field. The gaseous material is flowing from a southern hole in the sun's atmosphere. Arctic auroras could appear as early as Jan. 15th in response to a CIR traveling ahead of the stream.

Solar wind
speed: 365.9 km/sec
density: 8.9 protons/cm3

Updated: Today at 1606 UT

X-ray Solar Flares
6-hr max: C4 1333 UT Jan14
24-hr: M1 0203 UT Jan14
explanation | more data
Updated: Today at: 1610 UT