[Launch Alert] Vandenberg AFB Launch Schedule

[Launch Alert]

                             LAUNCH ALERT
 				  
			      Brian Webb
		  launch-alert-editor at earthlink.net
	                www.spacearchive.info
		       
                               2019 August 30 (Saturday) 20:05 PDT
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		   VANDENBERG AFB LAUNCH SCHEDULE

         All launch dates and times are subject to change.

                           Launch
                         Time/Window
       Date               (PST/PDT)           Vehicle       Pad/Silo
------------------    -----------------    -------------    --------

January               Unknown              Falcon 9         SLC-4E
Vehicle will launch Argentina's SAOCOM-1B earth observation satellite

The above schedule is a composite of unclassified information
approved for public release from government, industry, and other
sources. It represents the Editor's best effort to produce a schedule,
but may disagree with other sources. Details on military launches are
withheld until they are approved for public release. For official
information regarding Vandenberg AFB activities, go to
http://www.vandenberg.af.mil.

All launch dates and times are given in Pacific Time using a 24-hour
format similar to military time (midnight = 00:00, 1:00 p.m. = 13:00,
11:00 p.m. = 23:00, etc.). 

The dates and times in this schedule may not agree with those on other
online launch schedules, including the official Vandenberg AFB
schedule because different sources were used, the information was
interpreted differently, and the schedules were updated at different
times.

PDT: Pacific Daylight Time

PST: Pacific Standard Time

SLC: Space Launch Complex

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                   WHY ARE SUNSETS TURNING PURPLE?
                          Spaceweather.com
                            2019 August 27

Every year, on average, about 60 volcanoes erupt somewhere on Earth,
shooting ashy plumes of sulfurous gas thousands of feet into the air.
Rarely do those plumes make it all the way up to the stratosphere.
This summer, however, two volcanoes have done it. The Raikoke volcano
in the Kirul Islands (June 22nd) and the Ulawun volcano in New Guinea
(Aug. 3rd) both punched through to the stratosphere, sending material
as high as 60,000 ft.

The action of these two volcanoes may explain why many sky watchers
are starting to notice purple sunsets.

Why purple? Fine volcanic aerosols in the stratosphere scatter blue
light which, when mixed with ordinary sunset red, produces a violet
hue. The purple color is often preceded by a yellow arch hugging the
horizon. As the sun sets, violet beams emerge from the yellow,
overlapping to fill the western sky with a soft purple glow.
High-quality pictures of the phenomenon often show horizontal bands
cross-crossing the yellow arch. These bands are the volcanic gas.

Sky watchers shouldn’t expect to see purple every night. The volcanic
gas appears to be patchily distributed, bringing strange sunsets on
some nights, not all. Clear air, lack of clouds, and country settings
improves their visibility.

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Copyright 2019, Brian Webb. All rights reserved. No portion of this
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