[Editor's Note: An observant reader sent me a note about yesterday's posting from NASA about the "Aurigids" meteor shower  Commenting on the dust trail produced by this meteor shower, NASA wants us to know that the meteor's showers dust trail can pose a danger to satellites and to MAN WORKING ON  THE MOON. Apparently, the person responsible for writing this copy lost sight of the fact that the American public is not suppose to know that we (and the Russians, and the Germans, and surely the Chinese by now) have men working on bases on the moon since the 1950s. That information stream is suppose to be limited to NASA insiders, not the American taxpayer. It's going to be amusing to see how long this info remains posted at the NASA url posted below. Or, in the event that this boo boo gets more national attention, I'm curious to hear what NASA spin doctors and obfuscation artists have to say in order to cover the "bases" on this one. I guess we should take pity on the clown who's going to get hung over this; prevarication can be such a wearisome job you know...Ken]

http://educate-yourself.org/cn/nasadustworkingonmoon02sep07.shtml
September 1, 2007

NASA 'Education' Peddlers Get Their Moon Cover Story Confused (Sep. 2, 2007)

http://www.leonid.arc.nasa.gov/aurigids.html

The 1 September 2007 Aurigid outburst.

THE 2007 AURIGIDS AT A GLANCE

An airborne and ground-based observing campaign is being organized to monitor the unusual September 1, 2007, meteor shower called the "Aurigids". Click here for the mission website of the Aurigid Multi-Instrument Aircraft Campaign.

Predictions for the shower are summarized in this paper in the August 7 issue of EOS, Transactions of the AGU.

Comet Kiess Figure 1: Comet C/1911 N1 (Kiess)in an image by William Hoegner and Nikolaus B. Richter. At the peak of its return in 1911, the comet was a large diffuse nebula of +7 magnitude with a vague central condensation and a 0.2 - 0.5 degree long tail. [Click on picture for larger version]

THE 2007 AURIGIDS AT A GLANCE

What: A 2-hour outburst of bright (-2 to +3 magnitude) meteors radiating from the constellation Auriga (Radiant at RA = 92, Decl. = +39, speed Vinf = 67 km/s).

Why: The Earth will travel through the dust trail of long-period comet C/1911 N1 (Kiess), shown in Figure 1. Comet Kiess was discovered by Carl Kiess, a post doc at Lick Observatory, only days after Lick Observatory was hit by a damaging earthquake (an aftershock of the 1906 earthquake that destroyed San Francisco).

With the comet back on its way out, when was the dust ejected that makes up the comet dust trail: During the comet's prior return of around 83 BC, give or take a century, 2000 years ago at the beginning of our year count. The dust has since made one revolution, some particles making a wider orbit than others and returning later. There is a continuous stream of dust particles passing by Earth orbit, but only when the planets steer that dust trail in Earth's path do we see a meteor outburst.

Important because:

* Only known case in our lifetime: crossing of the dust trail of a known long period comet.
* Long-period comets, such as were Hale-Bopp, Hyakutake, and McNaught, tend to sneak up on us. They are a potential impact danger. What can the dust trail tell us about their physical nature?
* Their dust is a danger to satellites in orbit and man working on the Moon.
* Dust stream could contain material from original cosmic-ray produced crust of comet.

When: 2007 September 1, about 11:36 +/- 20 minutes UT (= 04:36 a.m. Pacific Daylight Savings Time).

(snip)