In yesterday's post we talked about a satellite that is keeping an eye on various heavenly objects that sail through our solar system at frightening speeds. These meteoroids (small) and asteroids (large) are in an orbit about the Sun so they have a go at us every so often. Once meteoroids hit the Earth's atmosphere they become meteors. Once asteroids hit our atmosphere they are called SHTFeroids. These objects range in size from microscopic to Texas.
The OSIRIS-REx spacecraft was launched by NASA several months ago to maintain a Game of Thrones type "Black Watch" on a celestial White Walker, Asteroid Bennu. OSIRIS-Rex will patrol the heavens without ceasing, be exposed to bad food and radiation and can never marry. This will be one pissed off satellite in a few years.
If the asteroid Bennu (with a diameter of 1640 feet) is a perfect sphere, it would have a volume of 85,602,045 cubic yards. However, asteroids are not planets and most are not shaped like them. Some asteroids are shaped like hemorrhoids; these are known as assteroids.
Some asteroids, such as Eros pictured below, are shaped like massive Idaho potatoes. But Eros is of the planet destroying variety; it is over 21 miles across, seven miles wide and seven miles thick. It is thought to have the mass of 700 trillion french fries.
Eros, delicious baked Eros
On the other hand, NASA has provided pictures of Asteroid 1999 RQ36 that indicate that it is shaped very much like a chicken McNugget; it is 560 meters across (1837 feet) so it is a little larger than our friend Asteroid Bennu, which is only 500 meters (1640 feet) across.
Crispy, crunchy, tasty, deep-fried 1999 RQ36
However, Asteroid Bennu is different. It is indeed shaped like a rabbit turd as shown below in this NASA photo.
Rabbit turds are spherical. This means that more calculations are forthcoming, prepare yourselves.
Turds ala' Oryctolagus Cuniculus
It is a very disquieting thought that a 500 meter turd traveling at .0000000006% of the speed of light could destroy a healthy chunk of our planet. But since they are spherical we can estimate the weight of a 1600 foot rabbit turd comprised of space dust/rocks. NASA states that Asteroid 199RQ36 has the same density as water so we'll use instead the weight of water which is 1728 pounds per cubic yard. This is lighter than rocks.
Since time is of the essence (and I'm getting bored with this) we'll blow through the math. So let's see, a sphere with a radius of 250 meters has a volume of 85,602,045 cubic yards and .86 tons per cubic yard (weight of water) gives us a 73.6 million ton asteroid.
Now allow Asteroid Bennu a low celestial speed so it won't get a ticket. That's 25,000 miles per hour in a school zone which is 11,176 meters/second; that produces a kinetic energy of 4,169,823,402,272 megajoules. One ton of TNT will release about 4184 megajoules of energy.
At that speed, if Bennu crashes into the Earth, it will yield a release of energy equivalent to a 997 megaton hydrogen bomb. That's 568% more powerful than the 57 megaton Tsar Bomba nuclear device detonated by the Soviets in 1961.
The next graphic shows the estimated blast radius of a 100 megaton hydrogen bomb if dropped on NYC (surface detonation). The yellow circle is the overpressure radius, everything not a bunker is either flattened or damaged. The red circle is the temperature zone which sends most combustibles into a combusted state. Everyone within about a four or five mile radius of ground zero(fireball country) is either people vapor or charcoal.
A 100 megaton bomb in an air burst would kill almost 11 million people and injure another 5 million. The fall out, if any, would sweep through the entire Northeast.
Imagine an explosion ten times more powerful. That would be Bennu.
Then there's the matter of all the Bennu ejecta that would make its way into the atmosphere. In 1883 the eruption of Krakatoa sent enough volcanic ash and monkey dust into orbit to eliminate summer the following year. Climatologists now state that the eruption affected the world's climate for perhaps a century. Although climatologists are a skittish lot that would flay the living flesh off their own children in order to get a lucrative government grant, comparing Krakatoa to Bennu would be like farting in a hurricane.