A Visit to Meteor Crater
It’s easy to forget that only just over half a century ago many – including the late british celeb’ astronomer Patrick Moore – believed that the craters of the Moon were volcanic.
One of the things which changed that was a combination of the brilliant NASA geologist Eugene Shoemaker and a strange hole in the desert just off old Route 66 near Flagstaff in Arizona. That hole is the privately-owned tourist attraction now known as Meteor Crater, that was once just the Barringer Crater - named after a guy who spent his life trying to prove it wasn’t just an old volcano like Sunset Crater nearby.
Privately owned tourist attractions out west tend towards the ‘World’s Biggest Pistachio – It’s Nuts!’ variety (at Alamogordo if you’re interested), but Meteor Crater is different. If you want to imagine what it’s like to stand on the surface of the Moon, this is your best opportunity on this world.
Meteor Crater has a chequered history. In 1891 a USGS geologist declared that it was the result of a phreatic (volcanic steam) explosion. He based this, not unreasonably, on the apparent absence of any large meteorite.
Then in 1903 Daniel Barringer’s Standard Iron Company acquired mining rights and studied the crater, concluding that it was caused by a meteorite impact. Unfortunately for Barringer (but not for us and his descendants) his subsequent attempts to mine the crater for its assumed huge iron meteorite were futile and financially ruinous.
Barringer’s mistake was that he seems to have imagined an impact event like a mountain falling into a field. In fact, the meteorite was much smaller and going much faster – at hypersonic speed – so when it hit, the impactor vapourised instantly with the energy of a nuke (~10 megatons, about the magnitude of the USA’s largest ever test).
We now know that the crater was formed 50,000 years ago, by an iron impactor likely less than 50m across by the time ablation in the atmosphere had taken its toll, in an event that would have produced the crater below in less than a minute.
Proof of this came in the 1960s when Shoemaker identified key geological features of an impact, including signatures like the high-pressure minerals Stishovite and Coesite and inverted stratigraphy (overturned rock layers) at the rim.
Overturned strata: this lump of Kaibab Limestone should be way down in there...
Meteor Crater was once thought to be volcanic, like this one nearby.
Crater seen from the access road just off I-40.
Meteor Crater is both easy to access and close to lots of other interesting places. It lies in the flat desert between Flagstaff and Winona and is visible from I-40. The crater is about 6 miles off the interstate at a junction 30 miles east of the turnoff to Walnut Canyon and Route 66 into Flagstaff.
It’s an easy side trip if you’re in the area to visit Flagstaff and the Lowell Observatory, or maybe the Grand Canyon. Just drive up Meteor Crater Road, park in a big lot below the rim, pay your entrance fee and you’re looking out over the crater minutes later.
What to see
When I first went to Meteor Crater in Arizona it was big on spectacle and short on interpretation. These days that’s changed and the visitor centre has the kind of serious and informative displays you get at the best public ones. And whilst you can’t walk the whole rim or descend into the crater anymore, the ticket price includes a free rim tour and lots of accessible viewing areas.
Visitor Centre and Museum
The VC has always had a large gift shop, but if you’re interested in astronomy and planetary science you’ll probably want to spend more of your time in the museum at its permanent ‘Collision and Impact’ exhibition.
There are lots of compelling exhibits and multi-media installations, including one on the 2013 Chelyabinsk event. Various interactive displays look at other recent falls and earthly craters; cratering off-world too. There’s even a simulator to really get you in a cataclysmic mood.
Also at the museum is the largest known fragment of the impactor itself (the Canyon Diablo meteorite), the ~0.8m Holsinger Meteorite.
On the outside of the rim, you can find a picnic area with a space capsule.
Permanent exhibition at the visitor centre has some fascinating displays.
They’ve added a number of different lookouts with paved access over the years. All have stupendous views, including one hanging right over the edge and another on a high point with vistas north towards the buttes of the Painted Desert and I-40 in the distance.
All are close to the visitor centre and the ones that look over the crater should be wheelchair accessible. The covered viewing area just outside the VC is level, but others are a steep ramp or flight of steps away.
Things to do
Free Rim Tour
Included with the entrance ticket (roughly at national park prices, but your pass won’t get you in – the crater is still privately owned), is a walking tour out onto the rim. Part of this is unpaved and will be hot in summer, but it’s worth it because you see more of the crater in its natural state, visiting overlooks and the ruins of Barringer’s house along the way.
The tour runs every hour for roughly 45 minutes and the guide will tell you all about the history of the crater and point out features like the overturned strata on the rim, remnants from the mining attempts and the Apollo Astronaut hanging out in the bottom of the crater for scale.
Note that you used to be able to walk right around the rim on your own and even down into the crater. I did these things thirty years ago, but erosion means it’s no longer permitted and the tour is your only access to the rim apart from the paved viewpoints.
Access to the unpaved rim is restricted to the hourly tour.
Suited and booted: there’s an Apollo astronaut down there by the mine workings!
Years until a human once again sees a lunar crater for real. For now there's this.
Meteor Crater is a more managed experience than it once was, with little opportunity to explore on your own. That said, the VC is much more interesting than it used to be and the free tour is great too. Meanwhile, the crater itself presents the singular outlook it always has.
Everyone should see Meteor Crater at least once. Squint and you’re on the Moon, astronaut and all.