This really needed a new thread as we were about to get WAY OFF of the thread.

In answer to Mike's comment which was a response to (...um./.. short term ,memory is shot) the mention of meteor showers... We can expect that the Leonid shower to be in the vicinity of 6 - 10 k/hr. Yes, I said six to ten thousand per hour. The reason they haven't been a problem before is that we visit this part of teh solar system only once in about 30 years. The dispersal will ramp up so that this year it will be in the range given and next year it may be in the 10-25k/hr range.

We'll all be much more informed Nov 16-17 of this year. At least I think it's Nov.

""The peak itself may climb up to 40 meteors pr second. Maximum is expected around Nov. 16-17."" from Astronomy Online site

The math is "LOTSA DEM!!" {60 X 60 = 3600 40 X 3600 = 144000 per hour..... .... um.... has one of us got a place holder error??}

Whatever, these little sand grains to 2# rocks are gonna do a NUMBER on the satelite system.

cr

-- Chuck a Night Driver (rienzoo@en.com), September 22, 1998

Answers

Do they list the odds of one of these things actually hitting a satellite? I couldn't find the article. Lotsa dem - yes, Lotsa space too. I'd like to see some odds, big numbers can be misleading.

-- Mike (gartner@execpc.com), September 22, 1998.

Here is part of an article on this subject:

A threat of another kind was outlined by David K. Lynch, a research scientist for the Aerospace Corp. of El Segundo, Calif. , who told reporters that between 500 and 600 satellites orbiting the earth will be "sandblasted" by a Leonid Meteoroid Storm due on Nov.17.

The storm occurs every November as the Earth intersects with the debris field formed by the Tempel-Tuttle comet but grows more severe every 33 years. The last time the shower appeared, there were fewer than 70 satellites.

While most particles in the dust cloud trailing the comet are smaller than grains of sand, they do travel at velocities faster than a .22 caliber bullet. "These are the fastest solid particles earth ever encountered," Lynch said.

While damage most likely will not occur from debris blasting holes in satellites, this "sandblasting" can create electrically charged plasma that could short-circuit computers and damage other sensitive electronic equipment, Lynch said.

He added, "It's going to be a great show. It will be one of the best meteor showers we've ever seen."

Because of the earth's position at the time, the showers of between 200 to 5,000 meteors an hour will not be visible from the United States but will be brightest from the vicinity of Japan, Korea, Okinawa and northern Australia and will last five to six days.

-- Pastor Chris (pastorchris@lifetel.com), September 22, 1998.

Pastor Chris--I think the BIG Leonid meteor shower is expected in Nov 1999, is it not?

-- Kitty in Chesa. VA (kittyfelton@webtv.net), September 22, 1998.

Here is a place to go for facts:

http://web99.arc.nasa.gov/~leonid/

-- Buddy Y. (buddy@bellatlantic.net), September 22, 1998.

Thanks to all for the new data.

In my innocence, I was only trying to point out that the showers this fall (Nov 1999) "might" destroy some more satellites, and thus we "might" get a better estimate of what will happen to utility and power command & control, and industrial control, and general telecommunications world wide, when computer-driven Y2K satellite problem hit.

But your info is even more serious (granting the probability of any single impact is ???) since it is evident that there will be an increased number of solids in the Leonid next Nov as well. (I should have remembered they are a part of a stream of debris in orbit, and so the peak year is followed by several other years of much "higher than normal" meteor impact.)

Oops, forgetting my basic statistics, orbital dynamics and astrophysics classes there.

This Y2K problem sure does stick its ugly nose in all sorts of areas doesn't it. I will, for once, put on my gloomy face 8<(

-- Robert A. Cook, P.E. (Kennesaw, GA) (cook.r@csaatl.com), September 22, 1998.

I geuss everyone has already been made aware of the predicted solar flares in 2000? They occur every 11 years and the last one was-you geussed it-1989. But this is probally old news you seasoned y2k pros!!

-- madeline (runner@bcpl.net), September 22, 1998.

Someone recently explained to me that fixed orbit satellites above the US will be quite shielded from the shower, given its direction. I also heard that many of the satellites can be positioned in such a way that they'll be parallel to the shower, decreasing somewhat the odds of a direct hit. Anybody with more technical info on these statements, please contribute! (Despite my concern over the potential damage to the satellites, I must confess I'm bummed that we here in the States will miss the show!)

-- Faith (faith-weaver@usa.net), September 23, 1998.

Does anyone know??? If we lost all satelites(worst case), would we still have telephones working?

-- Karen Shirer (kgshire@aol.com), September 23, 1998.

I'm not sure that I understand how the US would be shielded from anything on a planet that rotates on its axis once each 24 hours.

-- Uncle Deedah (oncebitten@twiceshy.com), September 23, 1998.

Uncle, I definitely agree there: the satellites are "fixed" w/r to a point on the equator, so they swing in a roughly circular arc 22K miles up. There, they still have at least escape velocity speed as they swing through the comet debris field. (relative speed would be much higher, 'cause the meteor debris field is also in orbit around the sun.

Oh well. Maybe too somebody got confused by thinking that since the meteors themselves will be visible most brightly in the Northern Hemisphere above Japan and China (at night, of course) we won't have impacts over here in the daytime.

Turning satellites may help somewhat, but then if any damage does occur so thrudters or radio receivers are hit, then NASA can't turn them back. If they face normally, then there are fewer things that need corrections.

-- Robert A. Cook, P.E. (Kennesaw, GA) (cook.r@csaatl.com), September 23, 1998.

Uncle,

<< I'm not sure that I understand how the US would be shielded from anything on a planet that rotates on its axis once each 24 hours. >>

As I read it, because of the size of the meteroid trail and the speed of the Earth's orbit around the sun, the planet will only be exposed to the thickest part of the shower for a few hours. One side of the planet will therefore not be exposed to the heaviest bombardment. This pass through, that section is the Western Hemisphere.

From a purely selfish point of view, I'm dissapointed. Biggest meteor shower since I've been old enough to stay up after dark and see it, and I'm on the wrong side of the planet! Dang.

-- Paul Neuhardt (neuhardt@ultranet.com), September 23, 1998.

Yeah, I'm disappointed too. But my daughter is the one really kicking and screaming. She stays up late just to see a partial lunar eclipse.

On the other hand, this means that any crators formed by the "larger" rocks in the dbris stream will also be on that side of the planet.

Too bad we can't "direct" some debris "sideways" a little to hit a few Chinese missile silo's. Of course, if you have a big enough rocket you could lob a couple of chunks of granite from Vandeburg or Cape Canaveral over the pole so they just sort of accidently land on top of a missile silo anyway......Impact at around 12,000 mph... wouldn't take more than couple 1000 pounds of rock....

-- Robert A. Cook, P.E. (Kennesaw, GA) (cook.r@csaatl.com), September 23, 1998.

I'm the kid who stayed up at nights looking for Comet Khoutek long after it became apparent that anybody not at the Mount Polamar (sp?) Observatory had no chance to see the damn thing!

Seriously, if folks are counting on a Y2K preview out of this they may be sadly dissapointed. Even with the concentration of debris expected, the chances of a satellite being disabled are still pretty slim, and several failures is positively remote. If Y2K causes problems in this area it most likely will be in ground stations, and if that is the case there will be problems communicating with virtually all of the satellites, not just one or two. This will be a poor test of what is (or isn't) to come.

-- Paul Neuhardt (neuhardt@ultranet.com), September 23, 1998.

Paul

Danke, I did not realize that the shower was of such a short duration.

Pan Am Sat calculates a 1/10th of 1 percent chance of an impact to one of their 16 geo stationary satellites.

-- Uncle Deedah (oncebitten@twiceshy.com), September 23, 1998.