YozoraAtlas

When can you see the Milky Way in Finland?

Nowhere in Finland does the bright core of the Milky Way climb clear of the horizon haze while the sky is fully dark. It peaks at about 1° in Kotka, Kymenlaakso, and that happens around midsummer, when the sun never gets 18° below the horizon. What you can see is the rest of the band, high overhead on dark nights. The longest moonless nights come from October to March.

Where in Finland is the Milky Way band brightest?

The band needs a dark sky more than anything. Each region with its longest moonless nights, how many of its places are Bortle 1 to 3, and its darkest place.

State or regionLongest dark nightsBortle 1 to 3Darkest place
LaplandOctober to February4 of 8Lemmenjoki National ParkBortle 3
North OstrobothniaOctober to March3 of 6Hossa National ParkBortle 3
North KareliaOctober to March3 of 4Petkeljärvi National ParkBortle 3
KainuuOctober to March1 of 2Hiidenportti National ParkBortle 3
North SavoOctober to March1 of 5Tiilikkajärvi National ParkBortle 3
South SavoOctober to March1 of 4Kolovesi National ParkBortle 3
Central FinlandOctober to March0 of 4Salamajärvi National ParkBortle 4
Päijät-HämeOctober to March0 of 3Päijänne National ParkBortle 4
PirkanmaaOctober to March0 of 11Isojärvi National ParkBortle 4
KymenlaaksoOctober to March0 of 4Repovesi National ParkBortle 4

The darkest places in Finland to see the Milky Way

  1. Lemmenjoki National Park Lapland · Bortle 321.88
  2. Hossa National Park North Ostrobothnia · Bortle 321.88
  3. Petkeljärvi National Park North Karelia · Bortle 321.86
  4. Patvinsuo National Park North Karelia · Bortle 321.83
  5. Pallas-Yllästunturi National Park Lapland · Bortle 321.81
  6. Oulanka National Park North Ostrobothnia · Bortle 321.81
  7. Syöte National Park North Ostrobothnia · Bortle 321.80
  8. Riisitunturi National Park Lapland · Bortle 321.78
  9. Urho Kekkonen National Park Lapland · Bortle 321.78
  10. Hiidenportti National Park Kainuu · Bortle 321.76

Sky brightness overhead in mag/arcsec²: higher is darker, 21.95 is a natural sky.

Which months have the longest dark nights in Finland?

Hours per night with the sun more than 18° below the horizon and the moon down, for the median place in 2027. From May to July most of Finland gets no full darkness at all.

6.9 hJan5.4 hFeb4.1 hMar1.2 hApr0.0 hMay0.0 hJun0.0 hJul0.3 hAug2.7 hSep4.9 hOct6.2 hNov6.9 hDec

How the Milky Way dates for Finland are calculated

The positions of the sun, the moon and the center of the Milky Way are calculated for every night of 2027 at each place. A night counts when the core stands more than 10° above the horizon for at least an hour while the sun is more than 18° below the horizon and the moon has set. These are calculated positions; whether a night is clear is only known closer to the date. How it works