Shooting star
Meteorites are the only extraterrestrial objects that have ever landed on Earth, and are the closest we will get to being able to study other planets until we actually get there ourselves
There are few places on Earth that feel bigger than the vast 130,000 square-mile expanse of the Colorado Plateau in southern USA. As we drive through this desert landscape in an Audi Q2, we are swallowed up: the horizon rolls on as far as the eye can see, and everything we come across seems unnaturally oversized. Even the road signs are massive and, turning off the historic Route 66 near Winslow, Arizona, we follow a giant one pointing towards Meteor Crater.
This mile-wide hole is our first destination on a mission to learn more about meteorites, and how they could help mankind unlock the mysteries of the universe – explain where we come from, and where we are going. It’s also a great opportunity to see if Audi’s diminutive SUV can prove its worth on a wide variety of terrain, making the most of its raised ride height and quattro all-wheel-drive technology.
Meteor Crater was created some 50,000 years ago after a meteorite collided with Earth. It is calculated to have been approximately 150 feet in diameter, weighing several hundred thousand pounds and containing sufficient iron-nickel to produce about 42,000 new cars. At the time of impact it was travelling at 26,000mph, and the collision rocked the American south-west with a force equivalent to more than 20 million tonnes of TNT going off.
The main meteorite has never been retrieved, as it started disintegrating upon entering the atmosphere and then exploded on impact. But thousands of fragments of various sizes have been found nearby, including the Holsinger meteorite, which weighs more than half a tonne and is on display in the visitor centre. The crater is a popular destination for space enthusiasts, and it attracts more than 200,000 visitors each year. It’s the best-preserved crater of its kind in the world, and is similar to the one that wiped out the dinosaurs, which landed a few thousand miles south, just off the coast of Mexico.
After a few hours of comfortable highway cruising, our next stop-off is the Tucson Gem, Mineral & Fossil Show. For a few weeks each spring, this small southern city is overrun by tens of thousands of geology enthusiasts from all around the world, who come to trade, collect and discover. More than 5000 stalls spring up in various locations around the city, bristling with rare minerals, gems and even dinosaur fossils. It’s one of the biggest events of the year for meteorite dealers, who come to meet up with enthusiasts and share their latest finds.
One of the most recognisable faces at the show belongs to Geoff Notkin, a meteorite hunter who has been coming here for more than 20 years. He is the owner of a locally based meteorite sales company called Aerolite, which has set up one of the biggest stalls at the 22nd Street Show, one of the city’s busiest trade halls. When we get near, we have to contend with the bustling crowds attracted by the large and rare meteorites on display. They are also drawn to Geoff himself, who is a bit of a celebrity in his own right after starring in a TV show called Meteorite Men.
‘Meteorite-hunting has taken me on adventures all around the world,’ he explains. ‘These bolides [very bright meteors] can fall with equal probability anywhere on Earth, so a hunt could just as easily lead you to Tucson as it could Timbuktu. Some landscapes are much better for spotting meteorites than others, though. The best places are dry with little or no vegetation, such as hot or cold deserts, where the meteorites stand out from the rest of the backdrop quite vividly. That’s why Arizona has many prime hunting spots.’
“Meteorite-hunting has taken me on adventures all around the world,”
In such a landscape, Geoff would usually head out on a hunt armed with special metal detectors. He scours the ground looking for meteorite fragments, which can be detected due to their magnetic properties. Aside from this random approach, there are two other kinds of meteorite hunt: historic and fireball.
Historic hunts are his favourite, and lead him to reinvestigate locations where meteorites have been found in the past. Often he will study archives looking for old references of meteorite finds, and then use modern technology to pick up any pieces that were missed when the areas were first searched. A fireball hunt is the opposite, and involves tracking down a freshly fallen meteorite. It requires travelling to locations where there have been recent sightings of meteorites in the sky, and then deploying a wide variety of detectors.
‘Following fireballs can be quite a rush,’ he says. ‘If [the sighting] is well covered by the media then you will get quite a lot of competition from other hunters. These events are quite rare, and there are only a handful of notable events a year but it’s worth getting to the site first.’ Geoff explains that a large meteorite fragment can sell for tens of thousands of dollars to private collectors. Size isn’t the only determining factor when it comes to value, though, as the rarity of the meteorite’s composition also plays a role. ‘There’s also an analogy with the fine-art world, as the provenance of a piece can make it more valuable – it adds intrigue and wonder,’ he adds.
It’s not only collectors and enthusiasts who are interested in meteorites: the scientific community is also very involved. Some of the world’s leading universities and museums of natural history have extensive meteorite collections that are the focus of scientific research projects. Remarkably, there is a close relationship between enthusiasts, commercial interests and the world of science. Shows such as this one are regularly attended by academics, who come to acquire new material for study or trade specimens with dealers.
‘Without the meteorite sellers, it would be hard for us to get enough new material to study,’ states Meenakshi Wadhwa, director of the Center for Meteorite Studies at Arizona State University. ‘Of course we like to head off on our own field trips, but that’s not always possible. Quite often we won’t even hear of a meteorite discovery until a trader brings us a specimen, which they have acquired from somebody in a remote part of the world. We have a symbiotic relationship with the commercial meteorite trade.’
“Meteorites provide a way to look back into our past. It’s almost like time travel”
We meet Meenakshi at her custom-built laboratory in Phoenix, which is a few hours’ drive away. The sun is beating down, so we’re making full use of the dual-zone electronic climate control fitted to our Q2.
This facility houses one of the finest collections in the world, with more than 40,000 individual segments of 2000 different meteorites. Founded in 1961, it looks more like a museum of modern art than a research lab. The meteorites come in all shapes and sizes, and many of them have been cross-segmented to reveal eye-catching mineral structures within.
‘People often don’t realise how beautiful meteorites can be,’ she says, showing us how, as some cuts are passed through the microscope, they reveal a kaleidoscope of colours like a stained-glass window. ‘We look at different meteorites in many different ways, including extreme magnification, and also using magnetic spectrometers. But our interest reaches far beyond aesthetic considerations. For us, the meteorites provide a way to look back into our past. It’s almost like time travel, as they can show us what was happening 4.5 billion years ago. They are basically remnants of the formation of planets.’
Broadly speaking, there are three types of meteorite. There are stony mixtures of minerals called chondrites, which look like slightly sparkly lumps of rock. Then there are stony irons, which are half metal and half peridot (a type of mineral with a glassy, green/yellow aspect), but these account for less than two per cent of known meteorites. Finally, iron meteorites are made almost completely from iron-nickel metal, and often resemble lumps of twisted metal.
‘Meteorites are central to our understanding of how and when the Earth was formed, and might even hold clues to how life started,’ continues Meenakshi. ‘Meteorites are literally the materials that didn’t get folded into making planets. They’re the only extraterrestrial objects that have ever landed on Earth, and are the closest we will get to being able to study other planets until we actually get there ourselves.’
Meteorites don’t just play an elementary role in science but are central to ancient belief systems, such as Native American cosmology. After leaving Phoenix, we head north through the Navajo Nation before arriving in the Hopi Reservation, a high and barren area in the windswept plains of northern Arizona. In this part of the country the roads are poorly maintained, but the Q2 manages well. The car’s strong suspension absorbs the worst of the potholes, while being stiff enough to help us negotiate windy parts of the road.
This is one of the oldest permanent settlements in the whole of the USA. People have been living in adobe-style mud dwellings on three ‘mesas’ (the local name for flat-topped hills) since before the Norman conquest of Britain. The Hopi is one of Arizona’s oldest tribes, dating back to Paleo-Indian times, and its people were once nomadic. Today, there are 13,000 members spread among the reservation’s 12 small villages.
Our host in these lands is 67-year-old Leigh Kuwanwisisma, the former director of the Hopi Cultural Preservation Office. Leigh is a member of the Greasewood Bear Clan and has lived here all his life. For more than 30 years he worked for the tribal government in a number of roles. His mission was to record, preserve and pass on the culture, history and practices of his people.
‘All of our beliefs are encompassed simply in a code called the Hopi way of life,’ explains Leigh, speaking to us in his home on Third Mesa. ‘This comprises the experiences of the Hopi people since we travelled in the south-west, and talks about how we were created. According to stories, the spiritual people, called “kachinas”, gave us corn, and as a result we submitted to their rules of compassion, industry, respect, environmental stewardship and reciprocity.’
Oral tradition plays a massive part in sharing these stories, as do dances, which all focus on particular kachinas. These spirit beings are also represented by dolls, which are gifted to young girls to teach them about the different stories. There is one particular doll for the meteorite, with a black face to represent its ‘burning up’ in the atmosphere, and an eagle feather tail to symbolise the trail in the sky. Meteorites play a special role in wedding ceremonies, and have also had an influence on Leigh’s life.
‘We’re told stories about the meteors and that a meteor shower represents a bride going to a groom,’ he says. ‘When I was little, I couldn’t connect to that, but in 2013, we were preparing for my daughter’s wedding, and she started yelling, “Dad!” I heard this enormous roar and then ran outside. No more than a hundred feet up, we saw a fireball coming over the house from the east. It was red, yellow and pink, and you could see the ash, right over us. We were all scared – at first we thought that it was a plane crashing, but it was actually a meteor.’
A sighting such as this is a once-in-a-lifetime occurrence – but on the Hopi Reservation there are other opportunities to admire the beauty of outer space. Due to the remoteness of the villages and the near absence of light pollution, it is possible to do some first-rate stargazing.
‘Living in this remote place, you feel the tranquillity at night when you look at the stars,’ adds Leigh. ‘Sometimes, during the summer, I sit outside and just look at the cosmos. It is fascinating because it is the same sight that my great-great ancestors also saw in their lifetime.
It’s the eternal link.’
“You feel the tranquillity at night when you look at the stars”
As the sun goes down, we start to understand what he means. The view from the Hopi Reservation is a veritable feast for the eyes, and soon the entire sky is covered in bright white lights. The area gets less than 12 inches of rainfall per year, so there is barely any cloud cover, making clear nights like this a regular occurrence.
While admiring such a magnificent spectacle, it’s easy to start contemplating the scale of it all, and how far meteorites have travelled to land on Earth. When you consider how little we know about these rocks, it puts into perspective how little we know about the wider cosmos and the secrets it contains.
