Henbury
Key facts
- Country
- Australia
- Diameter
- 180 m
- Age
- about 4,200 years
- Location
- 24.57° S, 133.13° E
A cluster of about a dozen small craters in red desert country, the largest an oval about 180 m long and roughly 15 m deep, with low rims and scattered shrubs.
The Henbury craters lie in the red desert of the Northern Territory, about 130 km south-west of Alice Springs. They form one of the finest crater fields on Earth: a cluster of about a dozen craters made by the fragments of a single iron meteorite.
The impact. About 4,200 years ago, a large iron meteorite entered the atmosphere and broke apart before it hit the ground. Its fragments struck an area about a kilometre across, digging out craters ranging from a few metres to about 180 m long. The largest crater is not round but oval, probably because two fragments struck close together. Most of the craters are now shallow, partly filled with sand and silt washed in by rare rains, and many are ringed with shrubs and small trees that make use of the extra moisture.
The meteorite. Thousands of fragments of the iron have been collected around the craters. The Henbury meteorite is an iron of group IIIAB, made mostly of iron and nickel. When cut, polished and etched, it shows the Widmanstätten pattern, the criss-cross crystal structure typical of many iron meteorites. Some fragments were twisted and torn into sharp, jagged shapes by the force of the impact, while others are smoother and sculpted, probably shaped as they flew through the atmosphere.
Discovery and tradition. Aboriginal people of the region knew the craters long before Europeans arrived. Accounts recorded in the twentieth century describe a local tradition connecting the site with a fiery being from the sky and warning against drinking the water that collected in the craters. Some writers have suggested this tradition may preserve a memory of the impact, though this is impossible to prove. European settlers knew of the craters by the early twentieth century, and in the early 1930s a scientific investigation established that they were made by meteorite impacts. Henbury was among the first crater fields in the world to be recognised as such.
A protected site. The craters are protected within the Henbury Meteorites Conservation Reserve. A short walking trail leads around several of the craters, with signs explaining their formation. There is a basic campground nearby. The site lies a short drive along an unsealed road off the Ernest Giles Road. Removing meteorites, rocks or anything else from the reserve is illegal.
Why it matters. Henbury is an excellent example of a crater field, formed when an incoming meteorite breaks up in the atmosphere. Because each fragment makes its own crater, the size and spread of the craters reveal how the meteorite broke up. Henbury fragments are also among the most widely held iron meteorites in museum collections around the world.
Did you know?
The Henbury craters were all made by fragments of a single iron meteorite.
The largest crater is oval, probably because two fragments landed side by side.
Henbury was one of the first crater fields in the world to be scientifically confirmed.