Humans could likely survive impacts from asteroids up to several kilometers wide, like the ~10-20 km Chicxulub impactor that killed the dinosaurs, with survivors sheltering in deep bunkers or remote areas, but an asteroid exceeding 60-100 km (37-62 miles) would likely cause catastrophic global ecosystem collapse, making human extinction highly probable, though small groups in advanced underground shelters might persist temporarily, according to HowStuffWorks, Quora, ScienceDirect.com, and Forbes. The key factors are the impact's energy, the global climate disruption, and humanity's ability to shelter and store resources.
But, scientists believe some would survive. NASA scientists say it would take an asteroid 60 miles (96 kilometers) wide to totally wipe out life on Earth. Asteroid Didymos (bottom left) and its moonlet, Dimorphos are seen less than three minutes before NASA's DART spacecraft made impact.
Not anytime soon. It definitely will miss Earth in 2029 and 2036, and radar observations of Apophis during the asteroid's flyby in March 2021 ruled out an impact for at least the next 100 years.
The largest yield of a thermonuclear warhead is around 50--100 megatons. The kinetic energy of the falling object is converted to the explosion when it hits. The 10-kilometer object produces an explosion of 6 × 107 megatons of TNT (equivalent to an earthquake of magnitude 12.4 on the Richter scale).
NASA analysis of a near-Earth asteroid, designated 2024 YR4, indicates it has a more than 1% chance of impacting Earth on Dec. 22, 2032 – which also means there is about a 99% chance this asteroid will not impact.
A 300m-wide asteroid will not hit the Earth in 2036, US astronomers say. It was thought there was a one-in-200,000 chance that it could strike on 13 April 2036, but revised calculations have now ruled this out. Instead, Nasa scientists said it would not get closer than 31,000km as it flies past on this date.
If the object happened to be on an orbit that had it collide with Earth then there could be less than a year's warning. That is very unlikely. It is slightly more likely that an object will be discovered to be on a collision course only after several orbits, in which case there would be years or decades warning.
That one was estimated to be about 6.2 miles (10 kilometers) in diameter and marked the last known large asteroid to hit our world. Planet killer asteroids are space rocks that are 1 kilometer across or larger and could have a devastating effect on life.
Given enough warning, yes we could deflect it. As far as how much warning we would get is variable depending on if the asteroid approaches from the sunward side of earth's orbit or from the night side. But an asteroid that size would likely get detected years in advance.
The impact site, known as the Chicxulub crater, is centred on the Yucatán Peninsula in Mexico. The asteroid is thought to have been between 10 and 15 kilometres wide, but the velocity of its collision caused the creation of a much larger crater, 150 kilometres in diameter.
On April 13, 2029 (which happens to be Friday the 13th), something unsettling will happen. A decent-sized asteroid, the 1,100-foot-wide Apophis, will pass so close to Earth it'll be visible in the sky from certain places. Crucially, the giant rock will not strike our humble planet.
Astronomers closely tracked the asteroid, and now NASA is confident that there is no risk of Apophis impacting our planet for at least 100 years.
On September 11, 2025, Warp News estimated a 20% chance of global catastrophe and a 6% chance of human extinction by 2100. They also estimated a 100% chance of global catastrophe and a 30% chance of human extinction by 2500.
A 2021 study showed that a nuke detonated next to an asteroid 100 meters (328 feet) wide, at least two months before impact, could blast 99.9% of the asteroid's mass out of Earth's way.
It's the extinction of land-dwelling dinosaurs, and possibly the extinction of a competing group of mammals, that gave our primate ancestors the opportunity to thrive and evolve, a 2021 study found. If the asteroid had missed Earth, it's likely that humans, at least as we know them, never would have existed.
Birds have the closest DNA to dinosaurs, as they are direct descendants of theropod dinosaurs, making them living dinosaurs; chickens and ostriches, in particular, share strong genetic links with T. rex, confirmed through protein analysis and shared physical traits like scales and bone structure. While crocodilians (alligators, crocodiles) are also close relatives, birds are the most immediate living link to the dinosaur lineage.
In recent weeks, the chances of a so-called city-killer asteroid, 2024 YR4, hitting Earth in 2032 seemed to be more and more likely. However, NASA, the European Space Agency and others have since reduced those odds to less than 1%.
The Bible doesn't specifically address dinosaurs, when they existed, or how they became extinct. The closest examples of dinosaur-like creatures are translated in most Bibles as “serpent,” “dragon,” “Leviathan,” “Behemoth,” and “sea monster” (Job 3:8, Job 40:15-24, Isaiah 27:1, Ezekiel 29:3, etc.).
Impacts of projectiles as large as one km in diameter are generally thought to explode before reaching the sea floor, but it is unknown what would happen if a much larger impactor struck the deep ocean. The lack of a crater, however, does not mean that an ocean impact would not have dangerous implications for humanity.
Sedimentation on the floor of the gulf filled in the crater and eventually buried it beneath several hundred to ~1 kilometer of sediment. The Chicxulub crater is not visible at the Earth's surface like the famous Meteor Crater of Arizona.
The various layers of upturned rock eroded at different rates and produced the concentric pattern still visible today. Vredefort Dome, which measures about 90 kilometers across, was observed on June 27, 2018, by the Operational Land Imager (OLI) on Landsat 8. Notice that only part of the ring is visible.
Tsunamis produce most of the damage from asteroids with diameters between 200 meters and 1 km. An impact anywhere in the Atlantic by an asteroid 400 meters in diameter would devastate the coasts on both sides of the ocean by tsunami over 100 meters high.
Even if it did hit us, Apophis would cause localised destruction at best (akin to a large volcano going off), and since most of Earth is ocean, and we can see it coming a mile off and evacuate the area it's going to hit, the odds of it killing anybody at all are vanishingly low.
Our solar system is very big compared to the size of the Earth, which means that the chance that the Earth will be hit by another solar system object such as an asteroid is very small. Once in awhile, it happens. But not very often.