(meteorobs) Radio Orionids

[Ed Majden]

On 21-Oct-07, at 11:10 AM, stange34 at sbcglobal.net wrote:

> Ed, Will your new(?) spectrograph images be a different type from the 
> images
> of before?..... Similar to a meteor streak with spectra-radiation bands
> parallel to the travel path?
>
Larry:
	I'm not sure I understand your question.  All meteor spectra are 
similar, with emission lines for the elements present in the meteoroid 
with an atmospheric component.  There can also be a continuum  
radiation present sometimes made up of unresolved lines in the 
spectrum.  This continuum radiation is as yet not fully understood.  I 
suggest you download the IMO Photographic Handbook, Chapter 3 on meteor 
spectroscopy which should give you a better understanding of this work.
	As for my new spectrograph, I just took delivery of a surplus image 
intensifier.  It's Philips XX1332 Photonis night vision intensifier.  
It has a 50 mm input screen with a 40 mm output screen.  My old 
intensifier has a 25 mm screen so the larger XX1332 will allow me to 
get a wider field of view or better dispersion depending of the lens 
and grating combination selected.  I will use either an f/2.8 - 75mm 
f.l.  Bronica Zenzanon  lens or a Hasselblad f/2.8 - 80mm f.l.  Zeiss 
Planar lens fitted with a B&L 600g/mm blazed precision replica 
diffraction grating. Dr. Jiri Borovicka says he uses a very fast f/0.95 
- 50mm lens on a similar system but it suffers from off-axis distortion 
at the edge of the field of view.  My larger format lenses will be 
slower in speed but should not suffer as much from off-axis 
distortions.  I'm in the process of setting this up so it has not been 
posted to my web page.  Oh, I bought the surplus XX1332 intensifier 
from the UK which cost 245 GBP plus shipping and handling at 22.00 GBP.
Ed