- 3321 - ASTEROIDS - impact craters. - There are 190 confirmed impact structures on Earth. Despite our planet's habit of erasing these cosmic footprints, there are myriad craters still visible on Earth. Due to Earth's dynamic climate, processes such as weathering and erosion work to erase any trace of these cosmic visitors from our landscape. Some of the largest impacts ever to occur on Earth are barely visible to us today.
------------------ 3321 - ASTEROIDS - impact craters.
- Wolfe Creek Crater is a prominent feature of the Australian landscape. It is one of several strange sites that Earth holds as natural tourist destinations in the solar system.
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- Earth is perpetually bombarded with debris from outer space. Luckily for us, most of it burns up during entry through our atmosphere and we enjoy this bright burn in the night sky in the form of fleeting meteor showers.
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- But on occasion, an object is so big it survives its entry through the atmosphere and it leaves its mark on the planet . Impact craters are formed when a planet's surface is struck by a meteoroid, leading to the excavation of the surface material. These impact structures are characteristically roughly circular, excavated holes.
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- In South Africa, the Vredefort Crater is the world's largest known impact crater. Scientists believe the impact forged a crater between 111 and 186 miles wide, but as the crater has endured over 2 billion years of erosion, its exact size is difficult to determine.
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- Impact craters are our window into Earth's geological past. Scientists study these structures to understand the history of our dynamic solar system and use this information to predict future impact scenarios.
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- You can find each of the craters by typing in their name in the Google Earth search bar.
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------------------------------ 1. BARRINGER CRATER
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- Barringer Crater is approximately 570 feet deep.
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– Location: Arizona, U.S
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– Diameter: 0.8 miles
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– Depth: 570 feet
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– Age: 50,000 years
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- Barringer Crater, also known as Meteor Crater, formed relatively recently (geologically speaking) just 50,000 years ago when a large iron meteor measuring 98-feet to 164-feet in diameter, crashed into the Colorado Plateau in northern Arizona.
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- The 300,000-ton meteor was traveling at speeds of up to 26,000 miles per hour and exploded with the force of two and a half million tons of TNT, the impact excavated a 175 million tons of rock.
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----------------------------- 2. LONAR CRATER
- The Lonar crater site features in Hindu mythology and various temples are found along the edge of the crater.
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– Location: Maharashtra, India
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– Diameter: 6,000 feet
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– Depth: 500 feet
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– Age: 35,000 to 50,000 years
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- Nestled inside the Deccan Plateau in Southern India, Lonar Crater, is a large meteorite crater that has baffled scientists since it was identified in 1823.
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- The crater is located within a huge plain of basaltic rock left over from volcanic eruptions in the region 65 million years ago. The crater was originally thought to be a volcanic crater. Nowadays it is known that the crater formed between 35,000 and 50,000 years ago as a result of a meteor impact.
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- Lonar Crater is the only known impact crater to have formed in basalt. The unique ecosystem is a haven for local flora and fauna, the low crater hills are covered with trees and home to several species of wildlife including peafowl, chinkara and gazelles. Migratory birds flock to the lake during the winter months.
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- The crater site is also of great cultural significance and features in Hindu mythology. Lonar Lake is considered to be the place where Lord Vishnu slayed the demon-giant Lonasura and, as part of they mythology, the crater was the demon's lair and the lake was a result of its spilled blood.
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- This cultural importance is echoed by the temples, built around the 12th Century, found around the crater's edge. Most of the temples now lay in ruin, one temple dedicated to the local Goddess Kamalaja Devi is still used for active worship.
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- Scientists flock to Lonar Lake not only to study the unique basalt-based crater but also the lake itself which is both saline and alkaline.
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- In June 2020, Lonar Lake surprised scientists and locals alike when it turned a rosy pink. The striking color change was most likely caused by a large population of salt-loving microscopic organisms called Haloarchaea, or halophilic archaea, that produce a distinct pink pigment. The elaborate transformation was short-lived as by July 2020 the lake had reverted to its original form.
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---------------------------- 3. WOLFE CREEK CRATER
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- Wolfe Creek Crater lies in Wolfe Creek Crater National Park, Western Australia.
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– Location: Western Australia
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– Diameter: 2890 ft
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– Depth: 196 ft
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– Age: 120,000 to 300,000 years
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- Wolfe Creek Crater is on the edge of the Great Sandy Desert in the Wolfe Creek Crater National Park, northern Western Australia. The crater is believed to have formed 300,000 years ago, though, a recent study from the University of Wollongong in 2019 analyzed the radiation exposure of the crater rocks and placed an estimated age on the crater of just 120,000 years, far younger than previous estimates.
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- A prominent feature of the landscape, Wolfe Creek is the second-largest crater in the world from which fragments of a meteorite have been collected. Scientists estimate that the crater's meteor, which was 50 ft in diameter and weighed over 15,000 tons, was probably traveling at eye-watering speeds of 10 miles per second before slamming into the Australian desert.
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- The crater lies 90 miles from the nearest town, Halls Creek. This isolation has helped preserve the crater and surrounding.
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- Wolfe Creek Crater is home to some interesting wildlife including the vocal Major Mitchell's cockatoo harvesting seeds from plants on the crater floor and brown ringtail dragon lizards on the hunt for insects.
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------------------------------------ 4. GOSSES BLUFF (TNORALA)
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– Location: Northern Territory, Australia
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– Diameter: Originally around 13.6 miles (22 km), now 2.7 miles (4.5 km)
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– Depth: Originally 3 miles (5 km)
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– Age: 142 million years
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- Gosses Bluff, also known as Tnorala is of great cultural and scientific importance and is the most heavily studied impact crater in Australia. Sandwiched between the Macdonnell Range and James Range in the heart of Australia.
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- A meteor traveling at speeds of up to 25 miles per second slammed into Earth 142 million years ago, creating a giant crater nearly 14 miles wide. While the original crater has been eroded over the years, the core of the crater, a central ring of hills almost 3 miles in diameter, is still visible to this day.
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------------------------------- PINGUALUIT CRATER
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- Pingualuit is found in the heart of the Ungava plateau, Canada.
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– Location: Pingualuit National Park, Quebec, Canada
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– Diameter: 2.1 miles
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– Depth: 876 feet
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– Age: 1.4 million years
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- The Pingualuit National Park is situated in the heart of the Ungava plateau and is home to the impressive Pingualuit crater. Under the arctic sky, the crater is filled with pristine rainwater, cut off from inflows from other lakes.
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- This unique environment, 876 feet deep provides scientists with a window into the geological past. Sediments of Pinguluit lake were untouched during the Pleistocene Ice Age, a time period that began about 2.6 million years ago and lasted until about 11,700 years ago. While other sediments in surrounding water bodies do not extend further back than the last ice age, those found in the Pinguluit crater have preserved a much longer record.
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- The crater was first observed from the air in 1943 when the crew of a United States Air Force plane flew over the impact site. Expeditions did not commence until the 1950s due to the remoteness of the crater. However, there is evidence that that crater site has long been known to the local Nunamiuts, nomadic Inuit who lived on resources of the interior of the Ungava lands.
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- There are traces of rock shelters and stones arranged in a circular arrangement, evidence of where old tents would have been erected according to Nunavik Parks. The traces suggest the Nunamiuts once set up camps on the ridges of the Pingualuit crater whilst scouting for promising hunting grounds.
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------------------------------- 6. KAALI CRATER FIELD
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- The largest of the Kaali craters filled with water located on Saaremaa, Estonia's largest island
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– Location: Kaali, Estonia
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– Diameter: Largest crater 360 ft (110 meters)
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– Depth: Largest crater 72 ft (22 meters)
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– Age: Estimates ranging from 8400 to 2420 years old
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- Located on Saaremaa, Estonia's largest island, the Kaali crater field lies 11 miles from the island capital which consists of one large crater and eight smaller craters according to the news site The Baltic Times.
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- Remarkably, the island is thought to have already been inhabited at the time of the meteorite impact approximately 1530-1549 BCE though the age is still a matter of debate and estimates range from 2,420 years to 8,400 years old.
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- The meteor broke apart into fragments when it was just 3 to 6 miles above the ground. The pieces then smashed into the Estonian island creating some of Earth's youngest giant craters according to the tourist website Visit Estonia.
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- Domestic animal bones have been found at the site, and a large stone wall was built around Lake Kaali around the beginning of the Common Era which suggests the area was once used as a sacrificial site, according to Visit Estonia.
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--------------------------------- 7. NÖRDLINGER RIES
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- Nördlingen's town walls match the likely dimensions of the crater-forming meteorite.
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– Location: Western Bavaria, Germany
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– Diameter: 16 miles (26 km)
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– Depth: 660 feet (200 meters)
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– Age: 15 million years
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- The Ries crater contains a town within its inner ring, a town known as Nördlingen, according to the Planetary Science Institute. The full impact of the crater can only be seen when viewed from the air.
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- The crater's existence probably eluded medieval Europeans who unknowingly matched their town walls to the inner crater ring approximately 0.6 miles in diameter, likely the same dimensions of the crater-forming meteorite.
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- The true origins of the crater also eluded residents of Nördlingen as It was long believed that the Ries structure was an extinct volcanic crater.
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- The meteor was traveling over 43,000 mph when it hit the ground, exposing the surrounding rock to phenomenal pressure and heat over 45,000 degrees Fahrenheit. These extreme conditions created microscopic diamonds, the largest just 0.2 mm, within the suevite rock which was used to build most of the town.
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- Suevite is a type of rock created during impact events where rock is heated during the initial impact and then cooled, leading to fragments of rock and minerals. As such, this quaint little German town finds itself awash with tiny diamonds, approximately 72,000 tons.
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- The unique geology of the town even caught the attention of NASA. In August 1970, NASA carried out geological field trips and training in the Ries crater for Apollo 14 and Apollo 17 astronauts so that they could familiarize themselves with particular rock types that are associated with impact craters, which would later help them with their retrieval of rock samples from craters on the moon, according to the Geopark Ries site.
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------------------------------- 8. TSWAING CRATER
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- Tswaing crater reserve is rich in vegetation and wildlife.
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– Location: Gauteng, South Africa
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– Diameter: 0.8 miles (1.4 km)
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– Depth: 650 feet (200 meters)
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– Age: 220,000 years
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- Approximately 25 miles (40 km) northwest of Pretoria, within the area of the City of Tshwane, is the Tswaing meteorite crater. Tswaing is one of the best-preserved craters in the world and sediment deposits from the crater floor contain 220,000 years of climate records.
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----------------------------------- 9. TENOUMER CRATER
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- Tenoumer crater is a near-perfect circle.
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– Location: Mauritania
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– Diameter: 1.2 miles
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– Depth: 330 feet
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– Age: 10,000 to 30,000 years
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- Deep in the Sahara Desert is a near-perfect circular crater called Tenoumer. According to N-ASA Earth Observatory, the origins of the crater had long been debated amongst geologists, with some arguing that it was the remnants of a volcano, it is not agreed that Tenoumer is indeed an impact crater.
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- Tenoumer is one of the trickiest crater sites to visit due to its remote location. From the Mauritanian capital Nouakchott it's an 11-hour drive to the nearest town of Zouérat, which is about 124 miles away.
----------------------------------- 10. ROTER KAMM CRATER
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- Roter Kamm impact crater in Namibia looks like a scene that would be found on Mars.
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– Location: Tsau ǁKhaeb National Park, southwest Namibia
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– Diameter: 1.5 miles
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– Depth: 426 feet
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– Age: 5 million years
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- Amid the rusty-red dunes of the Namib Desert in southwest Namibia is a crater that looks like it'd be right at home on Mars. The Roter Kamm crater is found in the Tsau ǁKhaeb National Park (also known as the Sperrgebiet), a mining area in southwest Namibia. Scientists believe that the meteorite that formed this crater five million years ago was the size of a large vehicle when it collided with Earth.
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- The impact gave rise to a crater rim 131 to 295 feet above the surrounding plains whilst the crater floor is blanketed in sand deposits at least 330 feet thick.
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- October 30, 2021 ASTEROIDS - impact craters. 3320
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