Around 66 million years ago, an asteroid (or a comet) with a diameter of at least 10 kilometers (6 miles) impacted a few miles from the present-day town of Chicxulub in Mexico at around 64,000 kilometers per hour (40,000 mph). The impact triggered a chain of events what it is known today as the Cretaceous-Paleogene (K-Pg) extinction event, also known as the Cretaceous-Tertiary (K-T) extinction, and wiped out three-quarters of the plant and animal species on Earth, including non-avian dinosaurs.
If this Chicxulub impactor happened today, it would wipe out the human civilization. Luckily, events like Chicxulub impact are rare. Asteroids with a 1 km (0.62 mi) diameter strike Earth every 500,000 years on average. But that doesn’t mean we are totally safe. Asteroids with a diameter of at least 140 meters (460 ft) are big enough to cause regional devastation to human settlements unprecedented in human history in the case of a land impact or a major tsunami in the case of an ocean impact.
Continue reading Large Synoptic Survey Telescope will scan the skies for asteroids which threaten Earth
Around 66 million years ago, an asteroid or comet at least 10 kilometers (6 miles) in diameter impacted a few miles from the present-day town of Chicxulub in Mexico (hence it is dubbed as the “Chicxulub impactor”), at around 64,000 kilometers per hour (40,000 mph). The impact has created a crater (Chicxulub crater) more than 180 km (110 miles) in diameter. But, what’s more, the energy of the impact (which is equivalent of about ten billion Hiroshima atom bombs) vaporized the rock which was rich in sulfur compounds, filling the air with a thick cloud of dust, similar to that created by a catastrophic volcanic eruption.
This cloud blocked out the sun at least for a decade and caused a global, dark winter: even in the tropics the temperatures were barely above freezing, and the average global temperature was below 0°C (32°F). Before the impact, the average global temperature was around 26°C (47°F), so this means a huge drop. And the recovery time was more than 30 years! The dinosaurs which had dominated the Earth for more than 150 million years were used to living in a lush climate and were already in decline, so non-avian dinosaurs couldn’t survive after the last deadly blow.
Continue reading Dinosaur-killer Asteroid Triggered a Global Warming which lasted 100,000 Years
Hint: they are all space rocks. But, there are some differences. The biggest difference between an asteroid and a comet, for example, is what they are made of.
Continue reading What’s the Difference Between a Meteoroid, a Meteor, a Meteorite, an Asteroid, and a Comet?
I stumbled upon an amazing web page showing what did ancient Earth look like. On “Dinosaur Pictures and Facts” web page (dinosaurpictures.org), there’s also an interactive animation. On this page, you can either select the years (i.e. 600 million years ago) or jump to a particular event (i.e. first multicellular life) and see how ancient Earth did look like then. You can also remove the clouds and stop the Earth’s rotation if you want to.
Continue reading What did Ancient Earth Look Like
On 15 February 2013, an approximately 20-meter (66 feet) meteoroidNotes 1 entered Earth’s atmosphere over Russia, with a speed of 19.16 ± 0.15 kilometers per second (60,000-69,000 km/h or 40,000-42,900 mph). Its mass is estimated at 7,000 to 10,000 tons, one of the largest meteoroids entered Earth’s atmosphere in the recent history. Then, at 9:20 am local time (03:20 UTC), it exploded some 20 to 30 kilometers above the city of Chelyabinsk and created a gigantic fireball (known as a superbolideNotes 1) brighter than the Sun. An estimated 500 kilotons of energy was released by the explosion. For a comparison, the “Little Boy”, the atomic bomb dropped on the Japanese city of Hiroshima on 6 August 1945 exploded with an energy of approximately 15 kilotons of TNT. So, the Chelyabinsk meteor’s explosion was about 33 times stronger. The shock waves damaged several thousand buildings and injured approximately 1,500 people. No deaths were reported.
Scientists estimate such events occur on average once every 100 years. The most well-known was the Tunguska event, which occurred near the Stony Tunguska River in Yeniseysk Governorate (now Krasnoyarsk Krai), Russia, on the morning of 30 June 1908. It is also the largest impact event on Earth in recorded history. Studies have yielded different estimates of the meteoroid’s size, on the order of 60 to 190 meters (200 to 620 feet), depending on whether the body was a comet or a denser asteroid.
Continue reading Why meteoroids explode before they reach Earth?
According to the scientists who drilled into the Chicxulub crater buried underneath the Yucatán Peninsula and the Gulf of Mexico, the asteroid hit the “worst possible place”. They summarized their findings so far in a BBC Two documentary titled “The Day The Dinosaurs Died“. The documentary presented by professors Alice Roberts and Ben Garod.
Continue reading Dinosaur-killer asteroid hit “worst possible place”, say Scientists
Crocodiles are aquatic reptiles, and among the most feared carnivores on Earth, because of their size, big powerful jaws and aggressiveness. They are so successful predators – once they were living alongside the dinosaurs. After the Chicxulub impact, which happened around 66 million years ago, the non-avian dinosaurs were gone but crocodiles were managed to survive. Here are top 20 amazing crocodile facts about these fascinating beasts.
Related: Top 10 most googled crocodile whys
Continue reading 20 Amazing Crocodile Facts
Now we have a computer simulation of how the afterward effects of famous Chicxulub asteroid (estimated to be 10 km/6.2 mi) wide) killed the non-avian dinosaurs (and also a wide range of other species). On January 13, 2017, an article titled “Baby, it’s cold outside: Climate model simulations of the effects of the asteroid impact at the end of the Cretaceous”, published by the Climate scientists of Potsdam Institute for Climate Impact Research (PIK), revealed a detailed model of what happened to the atmosphere and the climate after the Chicxulub impact.
Continue reading How the darkness and the cold killed the (non-avian) dinosaurs
In the past, there were five major extinction event (a widespread and rapid decrease in the biodiversity on Earth), and a lot of minor ones. Now, we are in the middle of the sixth one, called “Holocene extinction event”. And the cause is… guess what? Humans.
According to the WWF’s (World Wildlife Fund) new Living Planet Report (2016), now we are in the middle of the biggest mass extinction on Earth, since the dinosaurs, which was around 65 million years ago. And the world set to lose two-thirds of its wildlife by as close as 2020.
Continue reading The Sixth Major Extinction Event