The explosion that creates a maar, for example, occurs naturally when water interacts with superhot magma from a volcano. Maars are a type of explosion crater as well as a volcanic crater. Artificial explosions that form craters usually happen underground. The explosion pulverizes or vaporize s material underground, and the earth above sinks. Craters formed by underground explosions are called subsidence crater s.
Craters formed by explosions at or near the surface of the Earth are simply called explosion craters. Drilling underground for oil and natural gas can lead to explosions and subsidence craters.
Machinery can sometimes encounter a pocket of natural gas that is under extremely high pressure. When drilling machinery puncture s the pocket of natural gas, the overlying rock layers may not be able to contain it. Like an enormous balloon, the gas pocket pops. As the gas is released in the explosion, a crater forms in the empty space.
A specific type of subsidence crater is formed by an underground nuclear explosion. Most nuclear testing is conducted in underground facilities. As the explosion displaces massive amounts of material, the earth above it sinks.
In fact, subsidence craters caused by underground nuclear explosions are sometimes called sinks. The Nevada Test Site , in the remote deserts of the U. The debris in and around nuclear subsidence craters often comes into contact with radioactive material.
For this reason, access to these sites is restrict ed. Bacteria Will SurviveYou Wont The impact of a meteorite that would result in the creation of a Chicxulub-sized crater is something astronomers call an extinction-level event ELE or biotic crisis. Meteorites are just one possible cause of an ELE. ELEs have happened more than a dozen times in Earths history.
Extinction-level events actually have little effect on Earths biodiversity. Most life on Earth is microbial. Microbes, such as bacteria and algae, are not significantly affected by ELEs. Its only the larger life formstrees, dinosaurs, peoplethat face biotic crises.
Rampart Craters Some craters on Mars hint that liquid water was probably present at some point in the planet's past. Rampart craters are a type of impact crater found only on Mars. Unlike craters on the moon, where debris, called ejecta, from the impact is spread out in neat lines, rampart craters show ejecta curving out in smooth, flowing lineslike a mudflow. Rampart craters look more like splashes than explosions. Also called an atom bomb, a-bomb, or nuclear bomb. The Earth is the only place in the known universe that supports life.
Gas molecules are in constant, random motion. Also called a Jovian planet. Also called a shooting star or falling star. Nuclear weapons testing was discontinued there in Also known as petroleum or crude oil. The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit. The Rights Holder for media is the person or group credited. Jeannie Evers, Emdash Editing.
Caryl-Sue, National Geographic Society. For information on user permissions, please read our Terms of Service. If you have questions about how to cite anything on our website in your project or classroom presentation, please contact your teacher. They will best know the preferred format. When you reach out to them, you will need the page title, URL, and the date you accessed the resource. If a media asset is downloadable, a download button appears in the corner of the media viewer.
If no button appears, you cannot download or save the media. Text on this page is printable and can be used according to our Terms of Service. Any interactives on this page can only be played while you are visiting our website. You cannot download interactives. A star system is a group of planets, meteors, or other objects that orbit a large star. While there are many star systems, including at least billion other stars in our galaxy, there is only one solar system.
That's because our sun is known by its Latin name, Sol. The solar system includes everything that is gravitationally drawn into the sun's orbit. Astronomers have discovered there are many other large stars within our galaxy, the Milky Way. Use these resources to teach students about the objects and relationships within our solar system. Impact craters are formed when a meteoroid, asteroid or comet crashes into a planet or a moon.
All the inner bodies in our solar system have been heavily bombarded by meteoroids throughout their history. This bombardment is clearly visible on the surfaces of the Moon, Mars and Mercury for example. On the Earth, however impact craters are continually erased by erosion or transformed by tectonics over time.
Still, almost terrestrial impact craters have been identified on our planet. These range in diameter from a few tens of meters up to about km miles , and they range in age from recent times to more than two billion years.
The impact craters featured on this list are relatively small and young making them easier to spot. An example of a large and old impact crater is the Chicxulub crater with a diameter of kilometers miles. The impact that formed this famous crater is thought to have been responsible for the extinction of the dinosaurs, about 65 million years ago.
It was created by a meteor with a size of a large vehicle about 3. The crater is clearly visible, but its floor is covered by sand deposits at least meters feet thick. Combined with the orangey-red color of the Namib Desert the crater gives the impression of a Martian surface rather than that of our own planet.
The Kaali Crater was created by a meteorite that reached the earth somewhere between the 4th and 8th century BC. At an altitude of about km, the meteorite broke into pieces and fell to the Earth in fragments. The largest crater is about meters wide and 22 meters deep. Within a 1 kilometer radius of the main crater lie 8 smaller craters that were created during this bombardment. The entire forest of the Estonian island of Saaremaa most likely burned down as a result of the impact.
The crater is part of many Estonian myths and stories. Nearly a perfect circle, the Tenoumer Crater is 1. Twin, lake-filled impact craters in Quebec, Canada were probably formed simultaneously, about million years ago, by two separate but probably related meteorite impacts.
Barringer Crater. Barringer Crater: well preserved. Measuring 1. Most of the meteorite was vaporized or melted, leaving only numerous, mostly small fragments with in the crater and scattered up to 7 km from the impact site. Only about 30 tons, including a kg sample, are known to have been recovered. Wolfe Creek Crater 7. Wolfe Creek Crater, well preserved, too. Another relatively well-preserved meteorite crater is found in the desert plains of north-central Australia.
Wolfe Creek crater is thought to be about , years old and is meters across and and about 60 meters deep. Deep Bay Crater. Credit: NASA 8. Deep Bay Crater: deep and cold. Deep Bay crater is located in Saskatchewan, Canada. The bay is a strikingly circular 13 km wide impact crater and is also very deep m.
It is part of an otherwise irregular and shallow lake. The age of the crater is estimated to be 99 million years old. Kara-Kul Crater.
Credit: NASA 9. Kara-Kul Crater: high altitude crater. This crater was formed about 10 million years ago, and is located in Tajikistan, near the Afghan border. In total, the crater is about 45 km in diameter and is partially filled with a 25 km-wide lake. It was found only recently from satellite images.
Bosumtwi Crater. Bosumtwi Crater: built of bedrock. The last crater on our tour of impressive impact craters is this located in Ghana, Africa. It is about The crater is filled almost entirely by water, creating Lake Bosumtwi. The lakebed is made of crystalline bedrocks. Source: Wikipedia: Impact Craters. Made me wonder what a direct hit on a mountain range would look like.
It would probably take a top off a mountain, which would make a glancing blow pretty interesting.
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