[meteorite-list] Changes in radiants over time

[Sterling K. Webb]

E.P., List,

Most of this is straight from 
the Wikipedia; it's just the 
basics, but they say it so well.
https://en.wikipedia.org/wiki/Meteor_shower#Radiant_point

Meteor "streams" are dust and 
particles shed by comets and 
strung out along the comet's 
orbit. Some of these orbits 
intersect the Earth's orbit.

Many showers have a radiant 
point that changes position 
during the interval when it 
appears. For example, the 
radiant point for the Delta 
Aurigids drifts by more than 
a degree per night. 

The radiant also moves slightly 
from night to night against the 
background stars (radiant drift) 
due to the Earth moving in its 
orbit around the sun. 

The gravitational pull of the 
planets determines where the 
dust trail would pass by Earth 
orbit, but the same gravitational 
effects perturbs the trails. Over 
longer periods of time, the dust 
trails can evolve in complicated 
ways.

Both gravitational influences 
and radiation pressure disperse 
the meteoroids and creates much
broader streams.

The Taurids are particularly 
complex in their radiant changes:
http://articles.adsabs.harvard.edu/full/seri/JIMO./0033//0000041.000.html

Over the very long term, meteor 
streams precess just as the planets 
do. The precession of the meteoroid 
stream orbit caused by planetary 
perturbations will also alter the 
date on which a shower occurs. 
http://www.math.nus.edu.sg/aslaksen/gem-projects/hm/0102-1-stonehenge/predic
ting_meteor_showers.htm

An interesting piece by Duncan 
Steel on the association of Earth-
crossing asteroids with meteoroid 
streams:
http://link.springer.com/article/10.1007%2FBF00671497#page-1

Sterling Webb
---------------------------------------------------
-----Original Message-----
From: Meteorite-list [mailto:meteorite-list-bounces at meteoritecentral.com] On
Behalf Of E.P. Grondine via Meteorite-list
Sent: Tuesday, November 03, 2015 9:56 AM
To: mpml at yahoogroups.com
Cc: meteorite-list at meteoritecentral.com
Subject: [meteorite-list] Changes in radiants over time

HI all - 

This author, Bard Marsden, is claiming that the radiant of the Taurid Meteor
Stream has drifted over the millenia:

https://sites.google.com/site/fromthedeepoceanabove/

Based on the mythological evidence he has assembled, this may be likely, but
what would be the mechanics involved?

E.P. 
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