So once again, The Millennium Group, those bunch of whackos and conspiracy nuts, "unscientists", having failed with Galileo, and Comet Lee, are all twitterpated anew over the latest comet to come to thief attention:Comet West-Kohoutek-Ikemura. Amongst other things, these whackos claim that NASA is hiding the facts, that the NASA probes to Mars that failed may actually be still working, and being used to watch the comet, and that if the comet hits, it will cause all sorts of disasters, including, possibly, the destruction of Mars!. If it wasn't so pathetic, it would be laughable. Unfortunately, these nitwits generate a hysteria that feeds my local doomsday nutcase, (this from a press release):

To the People of God:

For many years now we have been watching the News to see if a comet called Kohoutek, would appear - as many Prophecies related to a Sign from God via a comet named Kohoutek. since 1970, Jesus and Mary have spoken often about a Warning sign that would be given to the world when the 9 Planets of our Solar System come in line, and the comet, Kohoutek.

In recent days the world famous Millennium Group, who focus on astronomy, have given a public statement about a comet West-Kohoutek-Ikemura, which is currently heading towards the planet Mars, on a possible collision course. Those interested in studying more about this comet may check-in to their website:Millennium Group

Jesus and Mary also spoke about the alignment of the planets, which is due this year in May, and the comet will be the nearest to Mars on the 28th May, 2000.

All the children of God know what to do and what to look for.

To the unbelievers: if this comet does hit Mars or its moons, that means trouble for all - so consider, as a precaution, to store food and water.

Set below are some of the Messages given to me about this. I wish God's Blessings to all.

The 'LITTLE PEBBLE'

Well, William has been utterly, conclusively, and comprehensively wrong each and every time he's picked a comet. Comet HALE-BOPP, Kohoutek, Lee, and now he can add this one.

Let me pass on this from a very smart guy, who runs one of the best astronomy websites on the Internet, Bad Astronomy:

Posted by The Bad Astronomer on March 03, 2000 at 14:47:17:

The Millennium Group is frothing at the mouth about a comet that will pass near Mars.

First, from Ron Baalke:

The closest Comet West-Kohoutek-Ikemura gets to Mars is about 6.5 million kilometers (0.04308 AU to be exact) on June 5, and is not going to hit Mars

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Second, the MG is nuts if they think this will damage Mars. Of course, their sanity is questionable. Still, I did a calculation about this, just to see what would happen.

Let's assume the comet is really big, and has a radius of 20 km.

Let's also assume the impact velocity is 40 km/s, which is the maximum possible velocity (and the real velocity is probably much smaller, more like 30 km/s). The total energy of an impact is 1/2 * mass * velocity^2 = 2.7 x 10^32 ergs.

To vaporize a planet, you need to basically overcome the gravity of the planet for every particle (in other words, picture removing one particle at a time, and calculating how much energy it takes to give that particle escape velocity, remembering that the gravity decreases as you remove more particles). The amount of energy needed to do this is called the binding energy, and is equal to 3/5 * G * mass^2 / radius. Using 6.67 x 10^-8 for G (Newton's constant), 6.4 x 10^26 grams for Mars' mass and 3.4 x 10^8 cm for the radius, I get an energy of 4.8 x 10^37 ergs to vaporize Mars.

This number is about 200,000 times the total impact energy of the comet. But wait! A lot of the energy of impact of a comet does *not* go into moving matter, it goes into the flash of light. Only a fraction goes into the actual moving around of planetary material, so really we'd have to pummel Mars with a million or more comets like this one to vaporize it, remembering that I was very generous with the mass and velocity. Bearing all this in mind, I think Mars is pretty safe. ;-)

A direct impact with one of the moons is a different story. Phobos has an average radius of 11 km and a mass of 1 x 10^19 grams. Plugging those into the binding energy equations yields 3.6 x 10^24 ergs. Our comet would make short work of Phobos! That's not surprising; they are about the same size and mass. Even being conservative with the comet's velocity and mass won't help; Phobos would be doomed. Deimos is even smaller, and would get blown to smithereens as well.

Luckily, the moons make small targets. Comets look big, but that's just due to the gas and dust surrounding the nucleus. The actual solid part is only a few kilometers across, and so the chance of it hitting one of the moons is vanishingly small. Space is big.