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(meteorobs) Fwd: Two more lunar impacts CONFIRMED, on 2 videos

Just received this - 

Kevin K

> Pedro Valdes Sada reports two lunar flashes that he
>  videorecorded near Monterey, Mexico, about half an hour
>  after the event seen by Brian Cudnik and recorded by me
>  that is now so famous.  He gives the times in his message,
>  copied below.  They are also on my tape, made in Mount
>  Airy, Maryland, at the times he gives!  Later today, we
>  will digitize these two new flashes and put them up at
>  http://iota.jhuapldot edu
>  They are also near the lunar equator.  We will be 
>  determining the exact times from the tapes when we can;
>  I'm sure they will agree to within the 1/15th or so
>  second of timing that we can probably recover from the
>  tapes.  I had a WWV minute tone recorded at 5:07:00 UT,
>  7 and 8 minutes before the flashes, respectively.  The
>  new objects are also probably Leonids, since it was still
>  near the time the peak was striking the Moon, but of
>  course we do not know for sure, since we don't know from
>  which direction the meteoroids approached the Moon.
>  
>  For observers, a key to my success in this endeavor was
>  the focal reducing lens that I purchased from Orion;
>  it decreased the f-ratio of my 5-inch Schmidt-Cassegrain
>  telescope from 10 to 6.3.  That not only increases the
>  field of view by more than a factor of 3 in area, but
>  also increased sensitivity by concentrating the seeing
>  disk of point sources onto fewer pixels, and allowed,
>  for example, recording (faintly) the Earthlit dark side
>  of the Moon.
>  
>  By measuring images showing the lunar cusps and terminator
>  taken before and after the 4:46:15 UT event, I was able
>  to determine that it occurred at an angle (measured from
>  the Moon's center, called "cusp angle" in occultation
>  terminology) of 77 deg. from the north cusp.  Using also 
>  the distance of 1.7' in from the edge, this puts the
>  impact point in Oceanus Procellarum (Ocean of Storms)
>  about 50 km east-northeast of the center of the 50-km
>  crater Cardanus, at selenographic longitude 71 deg. W.,
>  latitude 14 deg. N., with estimated accuracy of 2 deg. or
>  50 km.
>  
>  David Dunham, IOTA, 1999 November 23
>  _______________________________________________________
>       
>  Date: Tue, 23 Nov 1999 03:00:33 -0600
>  From: Pedro Valdés Sada <psada@ixdot netcom.com>
>  To: Joan and David Dunham <dunham@erols.com>
>  CC: David Dunham <david.dunham@jhuapldot edu>
>  Subject: Re: Lunar impact seen & videorecorded; more records sought
>  
>      Hi David,
>  
>      I videotaped the non-illuminated side of the Moon for a while before 
the
>  leonid meteor radiant rose. There was some trouble while doing it because
>  I had allready committed myself to help with a large number of people that
>  attended a talk I gave that night on the subject and then stayed for the
>  meteor shower. So I had to keep an eye on the camera and telescope at
>  the same time I was answering questions and talking with people.
>  
>      I checked my tape for the 4:46:15 UTC meteor crash on the Moon and
>  could not find it. I must have been aiming elsewhere. I am not sure where
>  because the FOV was too bright from the glare and I could not see the limb.
>  Another problem was that the portable telescope was not polar alligned
>  very well and I had to keep adjusting it every 5-10 minutes so the Moon
>  would not drift out of the FOV.
>  
>      At any rate, I have not checked all the tape, but managed to identify 
> two
>  very suspicious-looking flashes that lasted at most 2-3 frames. They 
> occurred
>  at 5:14:13 and 5:15:20 UTC (+-1 second). Please check your tape and
>  pass it along to see if anyone else can confirm them. The second one in
>  particular, was right on the edge of my camera's FOV. The first one I am
>  pretty sure was real since the image was a bit out of focus and
>  looked very much like the stars I taped for calibration after the Moon set
>  (the focus must have drifted since it was OK at the start of the night). I
>  will try and digitize the two frames involved. Unfortunately, on my VCR I
>  can only freeze-frame the second fainter one. There seems to be a
>  brighter one in between frames that I cannot freeze on the screen but can
>  see momentarily. As for location on the Moon of the possible impacts I
>  cannot say for sure since the Moon drifted constantly. I can say that it 
was
>  near the equator and close to the terminator since it drifted into the FOV
>  after a couple of minutes.
>  
>      Sorry that I cannot be more precise on the location and magnitudes. I
>  will try to grab the images involved and at least get a rough estimate of
>  the magnitude.
>  
>      Regards,
>  
>      Pedro Valdés Sada
>      Univ. de Monterrey, México
>  
>  
>  
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