National Space Society/Western Spaceport Chapter

“Twilight Phenomena” may be seen from as far away as 200 miles

VANDENBERG AFB, CA (January 13) — A Minotaur missile is scheduled for launch from Vandenberg AFB in
Santa Barbara County on Friday evening, January 14th — which could result in public sightings of the
“Twilight Phenomena” throughout the Southern and Central California area (see below).

The Minotaur is scheduled to lift off from the newly constructed Space Launch Complex-7 (SLC-7) at
7:04 PST, and head towards the Southwest to place several small satellites into polar orbit.

The launch window runs from 6:54 to 9:54 PST. If the weather is favorable, the launch should be visible
for at least 200 miles throughout the Southern and Central California area.


The “weird lights” occasionally seen by people during predawn or post-sunset hours above Southern and
Central California are not UFOs, space aliens, nuclear attacks or the latest signs of the Y2K Apocalypse
— but more likely the telltale sign of yet another rocket launch from Vandenberg Air Force Base in Santa
Barbara County.

This visual apparition is more commonly known as “Twilight Phenomena.”

Twilight phenomena is produced when unburned missile or rocket propellant particles and water vapor
left in the exhaust trail of a launch condenses and crystallizes in the less dense upper atmosphere. These
fragments, in turn, reflect high altitude sunlight, producing the spectacular, colorful effects when seen
from the ground in outlying areas from Vandenberg AFB.

The phenomena’s appearance varies with viewer location, but can usually be seen throughout the state
of California, and as far away as Utah and Nevada.

Twilight phenomena typically produces green, blue, white and rose colored clouds which take on a
corkscrew appearance as they are whipped around and twisted by wind currents. It is usually seen two
to three minutes after a launch, and can remain in the sky for over a half hour before dispersing.

Twilight phenomena most often occurs when a missile launch takes place within 30 to 60 minutes after
sunset or before sunrise as the rocket rises out of the darkness and into the sunlight. Since 1958,
Vandenberg has launched nearly 1,800 missiles and space launch vehicles from the West coast
spaceport — but only a small number of these have created the twilight phenomena.

Many observers in the general public have assumed — incorrectly — that the phenomena is the product of
a missile or rocket malfunction, but these events are not linked.


(The following Air Force news release details the launch)


Air Force Minuteman Set to be First Launch of New Millennium

LOS ANGELES AIR FORCE BASE, Calif., — For the first time ever, the Air Force will use a refurbished
Minuteman II rocket motor combined with Pegasus XL upper stages to launch satellites into orbit Jan 14,
expected to be the world’s first space launch of the millennium.

The famed Minuteman II rocket, deactivated as an offensive weapon system by the Strategic Arms
Reduction Treaty in 1991, was initially designed as an Intercontinental Ballistic Missiles (ICBM) delivery

Liftoff from Vandenberg Air Force Base, Calif., is set for 7:04 p.m. PST.

The Orbital Suborbital Program Space Launch Vehicle, a combination of rocket motors from the
Minuteman II and PegasusXL launch vehicles, is part of an Air Force effort to use surplus Minuteman II
components for suborbital and orbital spacelift in support of U.S. Government requirements. This
program is managed by the Space and Missile Systems Center Test and Evaluation Directorate located
at Kirtland AFB, NM

The goal of this launch is to validate the OSP Space Launch Vehicle’s spacelift capability. To determine
the mission’s success, SMC personnel will evaluate data measuring the successful separation of the
payloads and detailing whether the payloads were deployed in the correct orbit.

Currently having more than 350 Minuteman II ICBMs in storage, SMC/TE is working with the vehicle
contractor, Orbital Sciences Corporation of Dulles, VA, to demonstrate a reliable, economical and
efficient way to put these missiles to good use.

The OSP Space Launch Vehicle can operate with two fairings allowing for the launch of oversized
payloads. Using a multi-payload adapter, the vehicle is capable of launching several payloads of up to
750 lbs to a 400-nautical mile, sun-synchronous orbit. This is roughly 1.5 times the PegasusXL capability.

The payloads for the upcoming launch are integrated to the Joint Air Force Academy Weber State
University Satellite, or JAWSAT, multi-payload adapter. The four payloads are the U.S. Air Force
Academy’s FalconSat, Arizona State University’s ASUSAT, Stanford University’s OPAL satellite and the
Air Force Research Laboratory’s Optical Calibration Sphere Experiment.

Also attached to the multi-payload adapter are two experiments: NASA Marshall Space Flight Center’s
Plasma Experiment Satellite and Weber State University’s Attitude Controlled Platform.

Originally set to launch Dec 7, launch officials discovered electrical problems during the mission dress
rehearsal Dec 1. During this test, the C-Band Transponder, a safety device that notifies operators on the
ground that the rocket is still on its course, did not respond.

Officials had also discovered at that time that the Modular Avionics Control Hardware (MACH) was not
functioning properly. The MACH is a modular interface box, which controls telemetry, power transfer and
ordnance commands.

After destacking the upper two stages, the PegasusXL, Orion 50 and Orion 38, and the fairing, the
C-Band transponder was replaced, and the cause of the MACH malfunction was corrected with software

The second OSP Space Launch Vehicle launch is scheduled for the spring, carrying the Air Force Research
Laboratory’s MightySat II.1 payload.

Spaceport Systems International (SSI) is under contract to provide launch site and launch control
facilities as well as range support for both launches.

The launch set for Friday will be SSI’s first launch.

The Space and Missile Systems Center, located at Los Angeles Air Force Base, Calif., is the center of
technical excellence for developing and purchasing military space systems and manages more than $56
billion in contracts. The center has an annual operating budget of more than $5.5 billion and employs
about 3,400 people worldwide.

For more information, see SMC’s web page at:

The 30th Space Wing, located at Vandenberg AFB, will provide Range support for the launch.

Range support includes, but is not limited to:

— Ensuring safe, reliable and timely launch operations in support of DoD and commercial launch

–Providing a full range of valuable weather services, and:

–Control and operation of the Western Range for all spacelift and ballistic launches.

For more information about the payloads, visit the JAWSAT website at:

TRW, the OSP Space Launch Vehicle systems engineering and technical assistance contractor for Space
and Missile Systems Center, will be providing
a live web-cast and satellite feed of the launch.


Jan 14th, 5 to 11 p.m. EST / 2 to 8 p.m. PST

Telstar 6C /11

Uplink Frequency: 6145

Downlink Frequency: 3920 / Vertical

Arc Position: 93 Degrees West

Those interested in viewing the webcast must first visit this site to register and receive a password:

Minotaur Launch Technical Data

Launch Window Opens: 2000 JAN 14 18:54:20 PST (JAN 15 02:54:20 UTC)
Launch Window Closes: 2000

JAN 14 21:54 PST (JAN 15 05:54 UTC)

Launch Time: 19:04 PST (03:04 UTC)

Launch Pad: SSI launch facility (referred to as “SLC-7”), south Vandenberg AFB
Launch Pad Coordinates:

Latitude 34 deg. 34 min. north

Longitude 120 deg. 38 min. west

Launch Azimuth: 220.0 deg.

Vandenberg Launch Net

If the weather is clear Friday evening, ham radio operators in southern California plan to run
“Vandenberg Launch Net” to pass along Minotaur countdown status and discuss the launch.

The net will be convened at 18:30 PST on the 147.000 MHz Santa Barbara repeater
(131.8 Hz PL, +600 KHz offset).