Re: NK satellite may be real

Richard Clark (rclarke@mcst.gsfc.nasa.gov)
Sat, 12 Sep 1998 21:02:46 -0400 (EDT)

The 2nd stage impacted at 40.2N 149.1E at a downrange distance of 1646 km.
I've heard that the Japanese reported different values for some of the
flight events but I don't have their numbers.

The satellite and 3rd stage are supposedly in a 219 x 6978 km orbit.
Burnout must have been very close to perigee

For the 2nd stage, burnout was probably before apogee of the instantaneous
orbit by a small amount. To simplify the math I put it at apogee (TA_2_bo
= 180) and impact at TA_2_i = 195 (1646/110 = 15 deg). Flight path angle
would have been nearly 0 so the height of apogee must have been close to
the height of perigee of the final 3rd stage orbit. I can fit these
conditions with a 2nd stage orbit with a=4650km, e=.4 and burnout velocity
about v=6.0km/sec

The final orbit for the 3rd stage 27 seconds later gives a=9970 and
e=.339. Perigee velocity is 9.0 km/sec. 

I've never looked at any 'real' satellite launches this way so I don't
know if these numbers seem plausible or not. The implied acceleration
certainly seems high. This last announcement came out of State Department?

Richard Clark
rclarke@mcst.gsfc.nasa.gov

On Sat, 12 Sep 1998, Ron Lee wrote:

> If it is in orbit...where is the elset from OIG?  What is the catalog
> number?
> 
> Ron Lee
> 
> 
> At 07:35 AM 9/12/98 -0600, you wrote:
> >This is weird...
> >
> >WASHINGTON--Contradicting earlier reports, U.S. State Department officials
> >confirmed Friday that Pyongyang launched a satellite--not a missile--on Aug.
> >31.
> 
>