Places · Impact site
Campo del Cielo
A strewn field of iron meteorites four thousand years old, known to the local people and recorded by Spanish expeditions from 1576. Individual masses run to thirty tonnes.
The sky from here
The sky over this spot is zone 3 — rural transition, Bortle 3–4, with a naked-eye limit around magnitude 6.2–7.0. The Milky Way is clearly there but loses its detail near the horizon. Light domes are obvious in several directions.
Against that sky 106 of the 110 Messier objects are straightforward in 10×50 binoculars and 106 in a 130mm, with 38 reachable by eye alone. The nearest sky of Bortle 2 or better lies about 7 km south-east of here.
The Sun drops far enough below the horizon here for full astronomical darkness on every night of the year — which is not true of anywhere much further from the equator.
At its highest the galactic centre stands 89° up, which is the difference between a Milky Way with depth in it and a smear along the horizon. Of the 110 Messier objects, none are circumpolar and 2 never rise.
The sky here is kindest to Southern Pinwheel, Lagoon Nebula and Butterfly Cluster, 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.
Against that, Bode's Galaxy and Cigar Galaxy never clear the horizon here at all. No amount of aperture or patience changes that; the only remedy is to travel.
Read at 27.63°S 61.70°W. 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 Campo del Cielo?
Everything north of declination +62°. From 27.6°S that is a cap 28° in radius centred on the north celestial pole, which is 5.7% 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 5.7% around the south celestial pole is the same geometry inverted, and never sets.
How many hours of true darkness does Campo del Cielo get?
10 hours 50 minutes on the best night, around 21 June, falling to 7 hours 1 minutes around 21 December. The measure is astronomical darkness — the Sun a full eighteen degrees under — not simply the hours between sunset and sunrise. Every night of the year gets there eventually, which is the quiet advantage of not being any further from the equator than this.
When is the Milky Way best from Campo del Cielo?
Around 17 June, when the galactic centre crosses the meridian at local midnight — and because this is a southern site, that is also midwinter, with the longest and darkest nights of the year underneath it. The brightest part of the Milky Way reaches its highest point on the best nights available, rather than during a summer that will not go dark. That coincidence is most of the reason the world's large optical observatories are in the southern hemisphere.
How far is Campo del Cielo from the other sites on this map?
Its closest neighbour on this map is ALMA, 795 km away to the north-west. The nearest other impact site is Chicxulub crater, 6,220 km to the north-west. These are straight-line distances over the surface, not driving distances, and in this part of the world the two can differ considerably.