Pages

Showing posts with label Astronomy. Show all posts
Showing posts with label Astronomy. Show all posts

December 9, 2016

Bennu The Destroyer


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

Astronomers are still seeking a sour cream planet.

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

A cubic yard of rocks can weigh anywhere between 2,400 and 2,900 lbs. and scientists have estimated that 1999 RQ36 weighs 66 million tons. Operating under a federal grant, NASA scientists have calculated that it would take 57 years and 202.8 billion barrels of vegetable oil to cook a McNugget the size of Asteroid 1999 RQ36 in a fryer the size of Lake Mead. Yes, I calculated the amount of oil (at 42 gallons per barrel) it would take to fill Lake Mead. I am strange that way.

However, Asteroid Bennu is different. It is indeed shaped like a rabbit turd as shown below in this NASA photo.

Asteroid Bennu

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.


It Bennu ever hit NYC, I've a 50/50 chance of surviving in Syracuse, probably less. To see what effect a nuclear device will have on your location, go here. There's a 100 megaton limit.

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.

December 8, 2016

Just Sit Back And Enjoy The Show

Lemme see. Those huge rocks hurtling through the solar system are usually hitting anywhere from 25,000 to 160,000 miles per hour. If the satellite spots this rock when it's a million miles away, that  gives us maybe 40 hours to perhaps only six and a half hours to figure out what to do.

Somehow I don't find that very comforting.
A spacecraft is currently on its journey towards an asteroid, where it will collect and return samples that experts believe may hold the building blocks of life.

The asteroid, Bennu, crosses Earth's orbit once every six years and is set to pass between the moon and our planet in 2135. 
 
Scientists are worried the 0.3 mile (500-metre) wide asteroid's orbit could be tweaked by Earth's gravity as it passes by, causing it to smash into our planet later in the century.

Now Nasa has explained exactly how the spacecraft is built to be able to see the asteroid from as far away as a million miles (1.6 million km) and as close as just a few feet.
Story here:

March 5, 2016

The Real "Star"bucks



Dubbed CFBDSIR 1458 10b, the star is what's called a brown dwarf. These oddball objects are often called failed stars, because they have starlike heat and chemical properties but don't have enough mass for the crush of gravity to ignite nuclear fusion at their cores.

With surface temperatures hovering around 206 degrees F (97 degrees C), the newfound star is the coldest brown dwarf seen to date.
More here.