Places · Impact site
Sikhote-Alin fall
An iron meteorite broke up over the Russian far east in 1947 and left more than a hundred craters and thirty tonnes of recovered fragments — the largest observed iron fall in history.
The sky from here
This is a zone 1 sky — pristine on the nine-grade scale, Bortle 1–2, reaching roughly magnitude 7.2–8.0 unaided. 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.
That grade puts 107 of the catalogue within easy reach of 10×50 binoculars and 107 within a 130mm — 58 of them need no instrument at all. There is nowhere darker worth driving to; this is already among the better skies on the planet.
There is no season here in which the sky fails to get properly dark — the Sun clears eighteen degrees below the horizon on all 365 nights.
The centre of the galaxy only ever reaches 15° 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, 14 never set from here and every one of them rises at some point in the year.
Of everything in the catalogue, Sunflower Galaxy, Andromeda Galaxy and Cat's Eye Galaxy are the best served here, climbing to within a few degrees of straight up — 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.
Whirlpool Galaxy, Little Dumbbell 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.
Read at 46.16°N 134.65°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 Sikhote-Alin fall?
Everything south of declination −44°. From 46.2°N that is a cap 46° in radius centred on the south celestial pole, which is 15% of the whole celestial sphere. It is out of reach permanently rather than seasonally: no time of year and no instrument brings it above the horizon. The matching 15% around the north celestial pole is the same geometry inverted, and never sets.
How many hours of true darkness does Sikhote-Alin fall get?
Between 2 hours 43 minutes on the shortest night of the year, around 21 June, and 11 hours 44 minutes on the longest, around 21 December. That counts only proper astronomical night, with the Sun eighteen degrees down; the merely-dark hours either side of it are longer. The sky here reaches it on every night of the year, which is not true much further from the equator.
When is the Milky Way best from Sikhote-Alin fall?
Mid-June at its highest, with a workable season either side of it running from about May into September. Because 46.2°N keeps full astronomical darkness all year, the whole of that season is usable, which is not the case for observers much further from the equator, who lose the peak of it to summer twilight.
How far is Sikhote-Alin fall from the other sites on this map?
Vostochny Cosmodrome is the nearest thing to it here — 785 km to the north-west. The nearest other impact site is Tunguska event, 2,670 km to the north-west. Distances are great-circle, so they are what a signal covers rather than what a road does.