Posts Tagged ‘Asteroids’

Asteroid 2012 DA14 will not impact Earth

January 11, 2013 Leave a comment

da14orbitWritten by Leslie Haze of

It seems these days any information regarding an announcement of a Near Earth Asteroid (NEA) coming remotely close to Earth spirals out of control within minutes on the internet by “doomsday prophets”. It is inevitable. What they fail to recognize or report are the facts or truth. No research is done and the doomsday prophets immediately go into internet viral mode. It is unfortunate for the doomsayers because it will only add one more failed prediction to their rapidly infinite list of crock predictions. These tiresome predictions only confirm their idiocy.

Asteroid 2012 DA14 is a moderate asteroid classified 0 (No Hazard) on the Torino scale. This means no threat to Earth. This statement of course has no bearing for conspirators. This is not enough evidence to prove to someone who is unconvinced. Here I will explain how if the asteroid made impact with Earth, it would be so miniscule it would embarrass your dog. How could I possibly know this? Simple research of facts with side by side comparisons of similar asteroids. If you claim to be a “seeker of TRUTH” keep reading or you may stop now if you are looking for more hyped up disinformation.

Asteroid 2012 DA14 is only 45 meters or 148 feet in diameter. About the size of a commercial airliner. If the asteroid made it into Earth’s atmosphere it would most likely disintegrate some kilometers above the ground in a large explosion, which if it occurred over a populated area, would cause severe personal and structural damage. What does that mean? Anything 75 meters or less in diameter would not survive intact during its passage through our atmosphere.

Hypothetically let’s say DA14 miraculously didn’t disintegrate while entering the Earth’s atmosphere or was more than 75 meters in diameter. Let’s compare DA14 with the the Barringer Crater in Arizona. The meteorite that impacted here was a rare Type M made of metallic iron and was only 50 meters in diameter. This is the measurement after most of it burned up in the atmosphere. The Barringer Crater is 1,200 m (4,000 ft) in diameter, some 170 m deep (570 ft). Since the Barringer Crater meteorite was made of metallic iron (Type M) the impact caused far more damage because it was so heavy. Still it hardly produced an Extinction Level Event (ELE). (Please note there are 3 classifications of asteroids.)

It is estimated that more than 75% of all asteroids in the solar system are carbonaceous (Type C). Type C asteroids are asteroids made of carbonates. Composition is thought to be similar to the Sun, depleted in hydrogen, helium, and other volatiles. Type C asteroids inhabit the main belt’s outer regions, where as Type M is metallic Iron. The likelihood of DA14 being a Type M is 1% and the likelihood of a Type M actually impacting Earth makes the odds even less. On top of this, the likelihood of DA14 hitting a populated area makes it slim to none. You would have a better chance of winning the lottery. To give you a better understanding it would be like comparing a bowling ball (Type M) to a volleyball (Type C). Type C asteroids are much lighter and less destructive. Since Type C asteroids are less dense, they have a greater probability of breaking up into hundreds of pieces as they enter the atmosphere. Coincidentally the asteroid that created the Barringer Crater, even being a Type M, broke up before impact as well.

If asteroid DA14 were to enter Earth’s atmosphere on Feb 15, 2013 the explosion would produce the equivalent of 2.4 megatons of TNT. The asteroid that created the Barringer Crater had an impact energy estimated at about 10 megatons. That is about a 1/4 of what DA14 is estimated. Let’s say our calculations are off and it makes it into Earth’s atmosphere. Based on the facts given, DA14 would probably destroy a small neighborhood if it even were to explode above a populated area which is less likely than likely. The Earth is about 75% water and only 3% of land surface is covered by populated urban areas according to GRUMP data-sets. This means there is about a 3% chance the asteroid would explode near a populated area.

Based on all the facts given, even if DA14 was miraculously made of metallic iron we can see by comparing the Barringer Crater this would be the maximum damage. (Note: the Barringer Asteroid was much larger before it entered Earth’s atmosphere.) The damage it caused was nowhere near being an Extention Level Event. Sorry to disappoint anyone.

Asteroid 2012 DA14 will also not be visible to the naked eye. Also according to NASA/JPL there is an estimated cumulative 0.033% risk (1 in 3,030) of 2012 DA14 impacting Earth sometime between 2026 and 2069. There is an estimated cumulative 0.00018% risk (1 in 556,000) of 2012 DA14 impacting Earth sometime between 2078 and 2111.

So, to sum up:

  • The asteroid will not impact Earth on February 15, 2013.
  • There is an estimated cumulative 0.00018% risk (1 in 556,000) of 2012 DA14 impacting Earth sometime between 2078 and 2111.
  • It is rated a low −5.78 on the Palermo Scale. (The risk is less than 1/500000 of the estimated risk of another similarly sized near earth asteroid hitting Earth during that time period. It is estimated that there are more than a million near-Earth asteroids smaller than 100 meters.)
  • It rates 0 (No Hazard) on the Torino scale.
  • If it were to hit Earth, it is estimated that it would produce the equivalent of 2.4 megatons of TNT. The Tunguska event has been estimated at 3−20 megatons.
  • In 2012 there was a cumulative 0.033% risk (1 in 3,030) of 2012 DA14 impacting Earth sometime between 2026 and 2069. In 2012 it was also known that the asteroid would pass no closer to Earth’s surface than 3.2 Earth radii.

No, 2005 YU55 Won’t Destroy The Earth

July 28, 2011 Leave a comment

On November 8th of this year, the 400-meter-wide asteroid 2005 YU55 will pass the Earth, missing us by the comfortable margin of 325,000 kilometers (200,000 miles).

While this is the largest asteroid (that we know of) to swing past us for the next 17 years or so, YU55 is not an immediate threat to Earth. Its orbit does bring it close enough to our planet that it’s been deemed a potentially hazardous asteroid, but the orbit is well-enough known that we can rule out an impact for at least the next century. That’s long enough for me personally to not be concerned.

I’ve seen some small amount of buzz on the usual conspiracy sites about this asteroid, and I do see some folks trying to play this up a bit (search on “YU55 doomsday” for example), but fear-mongering chatter is surprisingly low for this event. I expect that by this fall you’ll be seeing breathless YouTube videos accusing NASA of covering up a imminent impact — and I don’t say this blithely; it’s happened before. Remember asteroid 2007 TU24? No? That’s because nothing happened, despite the claims of panic-promoters.

As you can see in this JPL animation below, in November YU55 will miss us by a cosmic mile as well (click to embiggen and get a clearer animation):

You can see the Earth at the center (the diagonal line if the Earth’s orbit around the Sun), the Moon orbiting the Earth, and the path of YU55. The scale on the bottom is a million kilometers, about 620,000 miles. The Moon’s orbit is roughly 770,000 km (475,000 miles) wide. The path of YU55 cuts a shallow chord across the Moon’s orbit, well away from our planet.

Still, there’s a chance for some real science on this rock. At that distance, it’ll appear so small (1/4 arcseconds across, where the Moon is 1800 arcsec across for comparison) that it’ll be too small even for Hubble to make much of it — at best, in Hubble’s cameras it will appear to be just two pixels across. And that’s even if Hubble could track it, which it can’t.

But the Deep Space Network of radio telescopes can actually get very high resolution imagery using sophisticated techniques, possibly getting images with a resolution of just 4 meters — the size of an SUV — on the asteroid. That means YU55 will be 100 pixels across, enough to see some details on the surface, including craters, boulders, and even possibly a moon if it has one. Pretty cool.

So anyway, just in case the icky underside of the internet tries to play this up later this year, shouting doom-and-gloom, let me be clear:

By Phil Plait.

%d bloggers like this: