Image: Airborne synthetic aperture radar image of Haughton Crater. North is to the top and the crater is about 20 km wide. Note that the Haughton River breaches the crater rim to the northeast and flows into Thomas Lee Inlet.
Devon Island is located in the Territory of Nunavut in Canada less than a thousand miles from the North Pole. Devon Island is also the largest uninhabited island on Earth, with a surface area of approximately 66,800 square kilometers.
One of the prime reasons why space researchers and planetary geologists are interested in Devon Island is that it has a large meteor crater - Haughton crater. Haughton crater is named after Reverend Samuel Haughton, a british naturalist who wrote the first account of the geology of this region in the 1850s.
Image: Impact on Devon Island. Painting by Michael Carroll, courtesy National Geographic.
Haughton crater is 40 kilometers across and was formed 39 million years ago when a large object perhaps a mile across slammed into Earth. The impact event dug a deep hole in the Earth's surface and exposed ancient rock layers.
The crater that formed also held a lake for a long time, which has long since dried up. Haughton Crater presently lies in a polar desert environment and is the only crater known on Earth to lie in such an environment.
Studying this crater, and the effect it had upon the surrounding environment, may also help us plan to look for similar things on Mars.
Image: Aftermath of impact. Painting by Michael Carroll, courtesy National Geographic.
The scientific research project, which seeks to study this unique environment, is named the Haughton-Mars Project (HMP). The HMP began conducting research on Devon Island in 1996 and has established a research station just outside the northwest corner of Haughton crater at 75°22'N latitude and 89°41'W longitude.
How do impact craters form? According to NASA:
Craters are bowl shaped depressions made when a meteorite collides with a planet or moon. Good examples of craters can been seen on the surface of the Moon.
Early in the history of the solar system, after the formation of the planets and their moons, there was still a lot of smaller objects in inter-planetary space. Over time many of these objects collided with the earth and moon. Because the moon has no atmosphere and is not geologically active, the craters are still visible. On earth, however, the workings of the atmosphere, water, and continental movements have hidden most craters. Over 150 impacts have been studied on the earth, though the true number will never be known.
Use the scroll bar to go back in time and see the order in which the impacts occurred.
When a meteorite actually hits, the impact can be tremendous. Many meteorites actually explode on impact or just above the surface leaving nothing visible but a crater. During impact, debris is thrown from the crater. This displaced earth is called the ejecta. It usually contains rocks of different composition melded together called breccia.
The shape and size of the crater depends on the size and velocity of impact. Small diameter meteorites (less than 4 kilometers or 6.4 miles) usually leave a round bowl crater, while larger meteorites cause craters with raised centers called the central peak. This peak is caused by the surface's attempt to rebound from the impact. Huge impacts can leave multiple rings in the earth's surface in the same way a rock creates ripples in a pond.
Related links
- What is the Haughton Crater?, Haughton-Mars Project
- Impact Craters at NASA's Observatorium
- Impact Craters, NASA Liftoff Academy
- Meteorites, NASA Liftoff Academy
- Haughton Crater, Earth Impact Database
- Mars on Earth: The NASA Haughton-Mars Project, Part 1
- Mars on Earth: The NASA Haughton-Mars Project, Part 2
