[Launch Alert] Pegasus Launch Viewing

[Brian Webb]

                             LAUNCH ALERT

			            Brian Webb
		         Ventura County, California
		         E-mail: kd6nrp at earthlink.net
	         Web Site: http://www.spacearchive.info

				             2006 March 14 (Tuesday) 05:44 PST
----------------------------------------------------------------------

                       PEGASUS LAUNCH VIEWING

Tomorrow's Pegasus XL/ST5 launch appears to remain on schedule for a
drop (launch) time of 06:02 PST during a 05:57:21 to 07:19:50 PST
launch window. The rocket will be released from an L-1011 jumbo jet
flying high over the Pacific west-southwest of Monterey. After a brief
free fall, the first stage rocket motor will ignite and the vehicle
should head south.

Many of you are probably interested in looking for the launch and want
to know if it will be visible.

The visibility of Pegasus launches varies tremendously with the
lighting conditions. Daytime launches are only visible to the unaided
eye along the coast from the area north of Monterey to Santa Barbara.
Night launches are faintly visible over a wider area that extends
roughly from San Francisco to San Diego and inland several miles.

However, dusk launches can be spectacular because the rocket's exhaust
plume is illuminated by the Sun and suspended against a dark sky.
These events and visible from northern California to Cabo San Lucas
(perhaps further south) and inland as far as Arizona.

Dawn Pegasus launches are probably less spectacular than their dusk
counterparts for observers in coastal California. During dusk
launches, the sunlight shines through the exhaust plume. Dawn
launches, on the other hand, produce a more subtle display because
the sunlight reflects off of the plume.

Based on past Pegasus XL launch observations and my experience
observing dawn launches of other types of rockets, here are my
visibility estimates for the tomorrow's launch. They assume a 06:02
PST drop time.

						Launch Time
						with Respect
				Sunrise	 to Sunrise		Estimated
     Location		 (PST)	   (min.)		Visibility
  ---------------		-------	------------	----------
  Bakersfield		06:07		    +5		Poor

  Los Angeles		06:04		    +2		Poor

  Monterey			06:17		   -15		Good

  San Diego			05:59		    +3		Poor

  San Francisco		06:21		   -19		Fair

  San Luis Obispo		06:13		   -11		Good

  Santa Barbara		06:09		    -7		Fair

----------------------------------------------------------------------

Copyright © 2006 Brian Webb. All rights reserved. This newsletter may
be distributed in its entirety without restriction. Excerpts may be
not be reprinted or posted elsewhere without prior permission.