From spencer Tue Jun 21 16:29:47 1994
From spencer Tue Jun 21 16:29:47 1994
Return-Path: <spencer>
Date: Tue, 21 Jun 94 16:21:51 MST
From: spencer (John R. Spencer)
To: oleroemer
Subject: Io Volcano News
Cc: spencer
Content-Length: 711
X-Lines: 15
Status: RO


Sorry to report that the very bright hot spot seen on Io by Schneider,
Sauter, and Spencer at the IRTF on May 30 is no more.  I observed an
Io occultation and eclipse by Jupiter on June 20, using the NSFCAM 1
- 5 micron camera at the IRTF, and Io's (Eclipsed/Sunlit) flux ratio in
the L filter (3.5 microns) was about 0.03, compared to 0.14 on May 30,
so Io's 3.5 micron volcanic flux has faded by a factor of 5 in the
past three weeks.  Seeing was very poor on June 20 so there's no
immediate information on where the sources of volcanic flux were on
that date, but the Jupiter occultation lightcurve will give some
clues.

I'll be observing another Io occultation and eclipse at the IRTF
tonight (6/22 UT).