[Prev][Next][Index][Thread]

No Subject


LEONID MULTI-INSTRUMENT AIRCRAFT CAMPAIGN 

Status of project as of  January 18, 2000 
=========================================

1. Leonid MAC Workshop

In order to explore opportunities for future observing campaigns during the
2001 and 2002 return (and perhaps a small scale effort in 2000),
we invite your participation in the second Leonid MAC Workshop,
Leonid MAC Workshop 2000, which will be organised in Tel Aviv, Israel,
from April 16-19, 2000.

The workshop aims to bring recent Leonid storm studies in focus and 
will discuss recent progress made in understanding the satellite impact hazard,
the origin of life, new meteor, meteor train and meteor shower models,
sprites (are they triggered by meteors?), impacts on the Moon, 
comet composition and ejection dynamics, the spectroscopy of meteors
and meteor trains, laboratory studies that help explain the observed
spectral features, remote sensing - new techniques that may be deployed
during future storms, and many other topics that relate directly to the
exploration of the Leonid showers.  

Registration deadline is March 01. All information can be found at:
http://leonid.arc.nasadot gov/workshops/


2. First results: True nature of Elves reveiled.

An unusual image of an "elve" was captured by M.J. Taylor and 
L.C. Gardner of the Space Dynamics
Lab., Utah State University, during the night of the Leonids 
storm at 02:10:00 UT.  Elves are the signature of lightning-induced 
"EMP" radiation absorbed at the base of the ionoshere at heights 
of ~80-90 km.  Two events were captured by intensified Xybion 
cameras mounted on both the ARIA and FISTA aircraft.  
The "donut" shaped elves consisting of a bright ring of light 
with a dark central hole reveal the true nature of the expanding 
disc of light produced by the lightning EMP.   
The high altitude airborne measurements permit this structure of 
the elve to be seen clearly for the first time. 
The image is shown at: http://leonid.arc.nasadot gov/leonidnews.html
H. Yano reports that this and ten other sprites were also recorded
with the High-Definition TV cameras onboard FISTA and ARIA. 

3. First spectrum of afterglow of a meteor.

Jiri Borovicka of Ondrejov Observatory reports a first-of-its-kind spectrum of 
a persistent train just after formation taken from FISTA 
following a bright fireball at 04:00:29 UT on November 18.  
The afterglow of the meteor was so bright that the
glow recorded on Jiri's slit-less spectrograph. The spectrum was also
captured in a spectacular set of images by Mike Wilson onboard FISTA, operating 
a low-resolution UV/VIS spectrometer. The images are shown at
http://leonid.arc.nasadot gov/leonidnews.html.

4. First visible spectra of persistent train.

NASA/Ames Astrobiology Academy student Matt Lacey, currently at 
Stanford University, obtained the first spectra of persistent trains some
tens of seconds after the trains formed. He used a new miniature
spectrograph with slit onboard ARIA in an experiment with Peter Jenniskens. 
Lines from oxygen and sodium atoms are readily identified, but the spectrum 
contains also other lines and molecular bands that have not been identified 
yet. We also learned that John Plane and Beverley Allan in a collaborate
effort made a successful detection of train emission from a ground-based site 
at Tenerifa, Canary Islands.

5. Moon impacts confirmed.

David Dunham reports the confirmation of at least six Lunar impacts during
the 1999 Leonid shower. The impacts were obtained by video imaging of
the dark part of the Moon's disk from locations in the United States
and south America. First results will be presented at the Lunar and Planetary
Science Conference in Houston (March 13-17).  

6. Multi-station imaging of bright meteors 

A first tally of ground-based observations from Spain by members of the 
Dutch Meteor Society has been made by Hans Betlem. Station Casa Nueva
has at least 700 meteors photographed. Punto Alto more than 900. 
At least 500-600 multi-station meteors are expected. The nights before
and after the peak night have given each 6 multi-station meteors.

A second network near Valencia (Xalo and Dos Aguas) has given similar
numbers of meteors, enough for a photographic meteor rate curves
(e.g. http://www.dmsweb.org).
 
 
- Peter Jenniskens


..........................................................................
 
 Peter Jenniskens       
             
   The SETI Institute                    e-mail: peter@max.arc.nasadot gov       
   NASA Ames Research Center                tel: (650) 604-3086
   Mail Stop 239-4                          fax: (650) 604-1088
   Moffett Field, CA  94035-1000 
 
   http://leonids.arc.nasadot gov/pjenniskens.html
 
                      1999 Leonid MAC    http://leonid.arc.nasadot gov
                      1998 Leonid MAC    http://leonids.arc.nasadot gov

   Send attachments to: pjenniskens@mail.arc.nasadot gov
To UNSUBSCRIBE from the 'meteorobs' email list, use the Web form at:
http://www.tiacdot net/users/lewkaren/meteorobs/subscribe.html