Robert Yes I found 'theis' also but Allen was lots quicker than I. However, I think I'm first with these -- Page 2 -- "To simplify the micro-meteoroid model, several assumptions weare made: " ( micro meteoroid; were). Page 3 -- "... (Dermott et al. 1994) ..." (Superflous full stop (period if you're American!)). Page 3 -- "The dust itself consists of large interplanetary micrometeoroids ... " (micro meteoroids). Page 3 -- "In situ dust detectors onboard the Galileo..." (on board). Page 5 -- "... measured on earth or by ulysses,... (Ulysses). Page 5 -- "... are measured simultaneouly, even though... " (simultaneously). Page 7 -- "...variations of the heliospheric magnetic field: 0.01 to 44000 nT". (Don't know what this should be but nT looks wrong to me. Don't think my knowledge will permit me to find any factual errors (if such should exist). There is such a lot to check isn't there? Paul D Send instant messages to your online friends http://au.messenger.yahoo.com