How many of you have read the book, "The Fire Came By" by Baxter & Atkins?

Question

Science has moved on since the events in the Siberian Tunguska on June 30th 1908 but this story still holds a facination. A Comet fragment makes sense to me but what do you think. Makes you wonder If there are any more Comet fragments out there?

On June 30th 1908 a fiery object was seen streaking over the heavly forested and mostly deserted Tunguska region of Siberia. The object detonated with the power of a small nucliar explosion flattening trees for a radius of approx 30km and leaving the now familiar telegrapg pole trees below the epicentre. This object is now believed to have been a Comet fragment that, passing through the atmophere, became superheated and detonated at an altitude of 6 to 8 miles. We hear much in the news about close encounters with asteroids but what about Comet fragments. They are not all shooting stars!

Answer 1

Never read it. Based on the modeling that surrounded the Shoemaker-Levy impacts on Jupiter back in 1994, a comet fragment makes even more sense than ever. Comets appear to be made of fluffy enough stuff to splatter on an atmosphere without penetrating far. A full sized intact cometary nuclei would deliver some chunks to the surface of the Earth. Anything much smaller than 1 km would not. (see first source)

There was a big controversy over whether smaller cometary fragments are still bombarding the earth in significant masses even today back in the late 80's to mid-90's. The rather vehement nay sayers were put to bed by satellite observations. (see second source)

Answer 2

There certainly are more comet fragments out there.

In 1994 we were able to witness several fragments, the remains of the comet Shoemaker-Levy 9, impact Jupiter.

There is no reason why a similar object could not impact the Earth.

In fact a loosely compacted body such as a comet or even some asteroids, exploding in the atmosphere, could have a much more devastating impact on life on Earth than a similar sized solid body that impacted the Earth directly.

You may have seen Horizon on BBC2 the other day. This speculated that there was a similar event to Tunguska, though many times more devastating, that occurred over Egypt about 30 million years ago. If not you may want to check out my second source.