The daily space weather record.
·Latest complete day: Sunday, October 18, 2026. Earth's magnetic field was quiet: the Kp index, a 0 to 9 scale where 5 and above counts as a geomagnetic storm, peaked at 2.3 in the 03:00 to 06:00 UTC window and averaged 1.5 for the day. Aurora stayed up near the poles. The Sun let off 4 small (C-class) flares; the biggest was C3.7 at 06:44 UTC, too small to notice on Earth.
Every morning the daily data run closes the books on the previous UTC day and writes one record: what Kp did in each three-hour window, every flare of C class or above with the strongest and its peak time, NOAA's sunspot number and radio flux for the day, and the solar wind measured at the L1 point. The records are grouped into one page per ISO week, so a quiet Tuesday sits beside the rest of its week instead of standing alone. Nothing is written by hand and nothing is rewritten after the fact, except that a day's sunspot line fills in one run late because NOAA posts it the following afternoon. The record began on August 28, 2026.
What did the last two weeks look like?
| Day (UTC) | Peak Kp (0 to 9) | Flares large / medium / small | Biggest flare | Sunspot count | Radio output | Solar wind peak (km/s) |
|---|---|---|---|---|---|---|
| Sun, Oct 18 | 2.3 | 0 / 0 / 4 | C3.7 | 82 | 137 | 606 |
| Sat, Oct 17 | 3 | 0 / 0 / 7 | C2.8 | 87 | 132 | 532 |
| Fri, Oct 16 | 3.7 | 0 / 0 / 12 | C6.0 | 81 | 131 | 771 |
| Thu, Oct 15 | 3 | 0 / 0 / 10 | C4.9 | 104 | 126 | 574 |
| Wed, Oct 14 | 3.3 | 0 / 0 / 7 | C6.9 | 124 | 123 | 680 |
| Tue, Oct 13 | 3.3 | 0 / 0 / 2 | C4.2 | 102 | 136 | 698 |
| Mon, Oct 12 | 3.3 | 0 / 0 / 4 | C1.1 | 93 | 123 | 615 |
| Sun, Oct 11 | 4 | 0 / 0 / 4 | C1.8 | 94 | 122 | 735 |
| Sat, Oct 10 | 7 | 0 / 2 / 7 | M6.4 | 99 | 126 | 931 |
| Fri, Oct 9 | 4 | 0 / 1 / 13 | M1.3 | 93 | 121 | 577 |
| Thu, Oct 8 | 2 | 0 / 1 / 5 | M6.7 | 69 | 119 | 416 |
| Wed, Oct 7 | 2.7 | 0 / 0 / 5 | C7.9 | 78 | 114 | 448 |
| Tue, Oct 6 | 3 | 0 / 2 / 11 | M1.8 | 77 | 113 | 591 |
| Mon, Oct 5 | 5.3 | 0 / 1 / 4 | M1.0 | 58 | 100 | 656 |
Click a day for its full entry. "Pending" means NOAA has not yet posted that day's sunspot count; it arrives the following afternoon. What each column means is explained below the week list.
Which weeks are on record?
What do the columns mean?
The Kp index says how disturbed Earth's magnetic field was, on a 0 to 9 scale; 5 and above is a geomagnetic storm, and the higher it goes the farther south the aurora reaches. Flares are sudden flashes on the Sun sorted by size: small (C-class) is harmless, medium (M-class) can briefly fade shortwave radio, large (X-class) is a major event. The sunspot count is NOAA's daily tally of dark spots, from 0 on a blank Sun to 150 or more near a cycle's peak. Radio output is the Sun's brightness at a 10.7 cm radio wavelength, another activity gauge: 70 is quiet, 200 very active. Solar wind is the stream of particles flowing past Earth, measured about 1.5 million km upstream; 300 to 400 km per second is ordinary, 600 and above stirs up storms.
Where do the numbers come from?
Kp is NOAA SWPC's estimated planetary K-index at 3-hour cadence. Flares are from the primary GOES satellite's X-ray sensor as listed in NOAA's 7-day event file, kept in the flare archive. The sunspot number, 10.7 cm flux, and new-region count are from NOAA's Daily Solar Data report. Solar wind figures are hourly means of the real-time L1 feed (speed, density, and magnetic field), kept in the solar wind archive. The assembled record for each day is daily-space-weather.json, CC BY 4.0. A day appears here only once all eight Kp values for it are final, and no published value is changed afterward.
How is this different from the Lumara Log?
The Lumara Log is written by a person, only when the sky does something worth an article: a big storm, an eclipse, a meteor peak. This record is written by the machine, every day, whether or not anything happened, so that the quiet days are on the books too. When the log covers an event, the record for those days holds the numbers behind it.