Places · Impact site
Tunguska event
An airburst of perhaps 12 megatons flattened 2,000 km² of forest in 1908 and left no crater. The first expedition did not reach the site for nineteen years.
The sky from here
The sky over this spot is zone 1 — pristine, Bortle 1–2, with a naked-eye limit around magnitude 7.2–8.0. The Milky Way casts a shadow. Airglow is visible, the zodiacal light reaches across the sky, and the darkest places on Earth look like this.
Against that sky 107 of the 110 Messier objects are straightforward in 10×50 binoculars and 107 in a 130mm, with 58 reachable by eye alone. There is nowhere darker worth driving to; this is already among the better skies on the planet.
Between 20 April and 22 August the Sun never gets eighteen degrees below the horizon from this latitude, so there is no astronomical darkness at all for those 125 nights. Nothing faint is observable in that window, however far you drive from the nearest town.
The centre of the galaxy only ever reaches 0° above the horizon from here, so the richest part of the Milky Way is always seen through the thickest air. It is the single biggest difference between this sky and one further south. Of the 110 Messier objects, 29 never set from here and 8 never rise.
The sky here is kindest to Bode's Galaxy, Cigar Galaxy and Little Dumbbell, each of which passes within a few degrees of overhead — an object at the zenith is being seen through the least air it will ever be seen through, and the difference against the same object low in the south is not subtle.
Spindle Galaxy, Owl Nebula and Pinwheel Galaxy never set from this latitude, so they are available on any clear night of the year rather than for one season of it.
Against that, Southern Pinwheel, Butterfly Cluster and Ptolemy's Cluster never clear the horizon here at all. No amount of aperture or patience changes that; the only remedy is to travel.
Read at 60.89°N 101.89°E. Darkness is estimated rather than measured; everything else follows from the latitude and holds along the whole parallel. How accurate this is.
Nearby
Questions
What part of the sky never rises at Tunguska event?
Everything south of declination −29°. From 60.9°N that is a cap 61° in radius centred on the south celestial pole, which is 26% of the whole celestial sphere. Nothing about the calendar or the aperture changes that — the cap is below the horizon at every hour of every night. Its mirror image, the same 26% around the north celestial pole, is circumpolar here and never goes down.
How many hours of true darkness does Tunguska event get?
It runs the full range: about 12 hours 40 minutes at best, near 21 December, and flatly zero at the other end of the year around 20 April, when the Sun stays too shallow all night for the sky to finish getting dark. Astronomical darkness is the Sun more than eighteen degrees below the horizon, which is a stricter thing than the Sun being down.
When is the Milky Way best from Tunguska event?
Late August, as a practical matter — not June, when it is highest. The galactic centre crosses the meridian at local midnight around 17 June everywhere on Earth, and from 60.9°N that date falls inside the stretch of summer when the sky never finishes getting dark. The core is therefore at its best in precisely the weeks it cannot be seen. By late August it is still up in the evening and the nights have come back, and that overlap is the whole northern season for it.
How far is Tunguska event from the other sites on this map?
The nearest is Popigai crater, about 1,260 km to the north. That is also the nearest other impact site, with the next one 2,430 km beyond it. Distances are great-circle, so they are what a signal covers rather than what a road does.