NAME: Martin Peters

ORGANIZATION: Teikyo University

MAILING ADDRESS:
Kugayama 2-23-7-209
Suginami-ku
Tokyo 168, Japan

E-MAIL ADDRESS:
martinpeters@twics.com

INTENT:
I definitely will attend IAU Symposium 172.

CONTRIBUTED PAPER:
I plan to submit a contributed paper. I prefer this communication to 
be a poster.

TITLE OF PAPER:
A theoretical exploration of extinction by matter associated with Oort 
Cloud comets.

ABSTRACT:
Comets are known to produce comae or atmospheres episodically at large 
heliocentric distances. The mechanism or mechanisms that produce this 
activity are unknown. If one of the mechanisms causing such activity 
does not depend on the Sun, then atmospheres containing the usual 
variety of cometary atoms, ions, and small molecules may exist 
surrounding comet nuclei in the Oort Region. This paper explores the 
extinction that may be expected to be caused by such atmospheres. 
Comets near the Sun also extinguish starlight, but because of their 
movement, the effect on any particular background object is fleeting 
and therefore not suitable for long exposure spectrography. Objects in 
the Oort Cloud, however, may be for all practical purposes fixed, 
except for the apparent motion due to annual parallax. If any Oort 
comets have atmospheres, and if there is a line of sight correspondence 
between it and a background object, its light should bear the mark of 
extinction by small molecules, hydrogen, dust, etc. Many aspects of 
this topic will be explored.  Observations which may be considered 
candidates representing this phenomenon will be discussed.

REMARKS:
I do not require a travel grant. I look forward to receiving further 
information about this summer's event.