Can you see the northern lights in Viby in October?

On dark, clear nights with enough activity. 31 of 31 nights at Viby have civil darkness, and 12% of past October days reached Kp 5.

How dark is Viby in October?

Viby averages 12.3 hours of civil night a night in October 2026, from 11 h 8 min on the 1st to 13 h 19 min on the last night.

How cloudy is Viby in October?

NASA POWER's 2001 to 2020 climatology gives Viby's 1 degree cell 71% mean cloud in October, against 71% for the whole year. It is an all-hours average, not a forecast.

What is the best night in October 2026 for aurora in Viby?

By darkness and moon alone, Oct 6, with 4 h of moon-free darkness inside 10 PM to 2 AM at Viby. Activity on that date will only be known hours ahead.

Is October or November better in Viby?

By civil night times the clear share, October scores 3.5 hours at Viby and November 3.0. October comes out ahead.

Viby · October 2026

Northern lights in Viby in October 2026

Answer

October gives Viby 12.2 hours of civil night on the 15th, the 5th darkest of its 12 months, under 71% mean cloud. 12% of October days since 1996 reached Kp 5, enough for the oval edge to reach Viby.

12.3 h

civil night, average night

SunCalc for 56.12, 10.15; NASA POWER; GFZ Kp

October against the rest of the year

2.5

3.0

3.2

2.3

1.6

1.8

2.5

3.4

3.5

3.0

2.8

October cloud at Viby averages 71% in NASA POWER's 2001 to 2020 record, close to its yearly mean of 71%. April is Viby's clearest month at 61%. That makes October the best month of Viby's year by civil night times clear sky, 3.5 hours. Århus, 5 km away, averages the same 71%.

Civil night at Viby starts October at 11 h 8 min and reaches 13 h 19 min by October 31 as the nights lengthen by 2.2 hours. SWPC's 10 PM to 2 AM window is fully dark on every night. True astronomical darkness, the sun 18 degrees down, lasts 9.3 hours on the 15th.

October night by night

October opens toward a new moon on Oct 10, with full moon on Oct 26, in Europe/Copenhagen dates. Viby gets 185 hours of civil night with the moon below the horizon across the month. The best of them for moon-free darkness inside 10 PM to 2 AM: Oct 6 (4 h), Oct 7 (4 h), Oct 8 (4 h).

1
69% lit
0.6 h
2
57% lit
1.6 h
3
46% lit
3.0 h
4
35% lit
4.6 h
5
25% lit
6.3 h
6
16% lit
7.8 h
7
8% lit
9.4 h
8
3% lit
10.8 h
9
1% lit
11.8 h
10
0% lit
11.8 h
New
11
2% lit
11.9 h
12
5% lit
12.0 h
13
11% lit
12.1 h
14
17% lit
12.1 h
15
25% lit
11.8 h
16
34% lit
10.9 h
17
43% lit
9.8 h
18
52% lit
8.5 h
19
62% lit
7.2 h
20
71% lit
5.8 h
21
80% lit
4.5 h
22
87% lit
3.1 h
23
94% lit
1.7 h
24
98% lit
0.3 h
25
100% lit
0.0 h
26
99% lit
0.0 h
Full
27
95% lit
0.0 h
28
89% lit
0.0 h
29
81% lit
0.6 h
30
71% lit
1.9 h
31
60% lit
3.4 h

Each cell is the night that starts on that date. Hours are civil-dark time with the moon below the horizon; the green rule scales with them. Green outline: new moon. Bone outline: full moon.

Activity in past Octobers

Viby needs Kp 5 for the average oval edge to sit overhead. 116 of the 930 October days from 1996 to 2025 (12%) reached it in the GFZ Potsdam record, one of the three most active months for that level; storm days with Kp 5 or more made up 12%. Viby sits at 56.2 degrees geomagnetic. By SWPC's rule the average oval edge is overhead at Kp 5, and aurora is usually visible on the northern horizon at G1 (Kp 5) or less.

October across Denmark

No month-page town in Denmark has more civil night on October 15 than Viby; the national median is 12.2 hours. Coming from September (9.9 hours at Viby), October adds darkness, and the nights keep growing into November (14.3 hours on the 15th).

Civil night on October 15 and October cloud, month-page towns in Denmark
Town	Civil night	Cloud
Viby	12.2 h	71%
Copenhagen	12.2 h	73%
Århus	12.2 h	71%
Odense	12.2 h	68%
Aalborg	12.2 h	77%

Darkness and moon, every night

Viby, October 2026: each night from local noon to the next noon
Night	Civil	Astronomical	Moon-free dark	Moon-free, 10 PM to 2 AM	Moon lit
Thu Oct 1	11 h 8 min	8 h 11 min	36 min	0 min	69%
Fri Oct 2	11 h 13 min	8 h 16 min	1 h 37 min	0 min	57%
Sat Oct 3	11 h 17 min	8 h 21 min	3 h 1 min	31 min	46%
Sun Oct 4	11 h 22 min	8 h 26 min	4 h 37 min	2 h 4 min	35%
Mon Oct 5	11 h 27 min	8 h 31 min	6 h 15 min	3 h 40 min	25%
Tue Oct 6	11 h 31 min	8 h 36 min	7 h 50 min	4 h	16%
Wed Oct 7	11 h 36 min	8 h 41 min	9 h 22 min	4 h	8%
Thu Oct 8	11 h 40 min	8 h 46 min	10 h 50 min	4 h	3%
Fri Oct 9	11 h 45 min	8 h 51 min	11 h 45 min	4 h	1%
Sat Oct 10	11 h 49 min	8 h 55 min	11 h 49 min	4 h	0%
Sun Oct 11	11 h 54 min	9 h	11 h 54 min	4 h	2%
Mon Oct 12	11 h 58 min	9 h 5 min	11 h 58 min	4 h	5%
Tue Oct 13	12 h 3 min	9 h 9 min	12 h 3 min	4 h	11%
Wed Oct 14	12 h 7 min	9 h 14 min	12 h 7 min	4 h	17%
Thu Oct 15	12 h 12 min	9 h 18 min	11 h 45 min	4 h	25%
Fri Oct 16	12 h 16 min	9 h 23 min	10 h 53 min	4 h	34%
Sat Oct 17	12 h 20 min	9 h 27 min	9 h 46 min	4 h	43%
Sun Oct 18	12 h 25 min	9 h 32 min	8 h 29 min	3 h 12 min	52%
Mon Oct 19	12 h 29 min	9 h 36 min	7 h 9 min	1 h 50 min	62%
Tue Oct 20	12 h 33 min	9 h 40 min	5 h 49 min	28 min	71%
Wed Oct 21	12 h 38 min	9 h 45 min	4 h 28 min	0 min	80%
Thu Oct 22	12 h 42 min	9 h 49 min	3 h 7 min	0 min	87%
Fri Oct 23	12 h 46 min	9 h 53 min	1 h 43 min	0 min	94%
Sat Oct 24	12 h 50 min	9 h 57 min	15 min	0 min	98%
Sun Oct 25	12 h 55 min	10 h 1 min	0 min	0 min	100%
Mon Oct 26	12 h 59 min	10 h 5 min	0 min	0 min	99%
Tue Oct 27	13 h 3 min	10 h 9 min	0 min	0 min	95%
Wed Oct 28	13 h 7 min	10 h 13 min	0 min	0 min	89%
Thu Oct 29	13 h 11 min	10 h 17 min	34 min	0 min	81%
Fri Oct 30	13 h 15 min	10 h 21 min	1 h 52 min	0 min	71%
Sat Oct 31	13 h 19 min	10 h 25 min	3 h 26 min	0 min	60%

Moon lit: SunCalc illuminated fraction at the middle of the 10 PM to 2 AM window.

Questions

Can you see the northern lights in Viby in October?: On dark, clear nights with enough activity. 31 of 31 nights at Viby have civil darkness, and 12% of past October days reached Kp 5.
How dark is Viby in October?: Viby averages 12.3 hours of civil night a night in October 2026, from 11 h 8 min on the 1st to 13 h 19 min on the last night.
How cloudy is Viby in October?: NASA POWER's 2001 to 2020 climatology gives Viby's 1 degree cell 71% mean cloud in October, against 71% for the whole year. It is an all-hours average, not a forecast.
What is the best night in October 2026 for aurora in Viby?: By darkness and moon alone, Oct 6, with 4 h of moon-free darkness inside 10 PM to 2 AM at Viby. Activity on that date will only be known hours ahead.
Is October or November better in Viby?: By civil night times the clear share, October scores 3.5 hours at Viby and November 3.0. October comes out ahead.

Sources and verification

SunCalchttps://github.com/mourner/suncalc
NASA POWER climatologyhttps://power.larc.nasa.gov/docs/services/api/temporal/climatology/
GFZ Potsdam Kp indexhttps://kp.gfz.de/en/data
NOAA SWPC, Tips on viewing the aurorahttps://www.spaceweather.gov/content/tips-viewing-aurora

Quoted figures last checked against their sources on 2026-09-30; next review 2026-12-31. Computed figures come from SunCalc and the IGRF-14 dipole as described in the methodology. Every quote is listed in the sources ledger.