[Launch Alert] Gravity Probe B Launched

[Brian Webb]

                             LAUNCH ALERT

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

				               2004 May 1 (Saturday) 20:12 PDT
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                      GRAVITY PROBE B LAUNCHED

After years of delays, NASA’s Gravity Probe B has successfully reached
orbit. A Delta II rocket left California's central coast on the
morning of April 20th and inserted the $630 million satellite into an
orbit that carries it over the poles. Preliminary information
indicated that the orbit missed the poles by a mere 100 meters.

After a six-week checkout, the spacecraft will begin testing
Einstein’s General Theory of Relativity, a profound concept published
nearly a century ago. Einstein devised the theory to reconcile his
earlier assertion that nothing can travel faster than the speed of
light with Newtonian physics' contradictory view that the effects of
gravity travel at unlimited speed. Among General Relativity's main
points is the idea that the presence of gravity alters space and time.

For several decades the theory has served as the foundation of our
understanding of space, time, and how the universe works on a grand
scale. However, compared to other scientific theories, General
Relativity has not been thoroughly tested. Over the course of a year,
scientists will measure how the spin of gyroscopes aboard Gravity
Probe B change as the fabric of space-time is distorted by the Earth’s
mass and twisted by its rotation.

Data returned by Gravity Probe B may verify General Relativity or
ultimately lead to a new theory.

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		       VANDENBERG AFB LAUNCH SCHEDULE
			       As of 2004 April 30

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

MAY 17             10:47-11:11          Taurus          SLC-576E
Payload is Taiwan's ROCSAT-2 satellite

JUN 19		 03:01:50-03:04:50    Delta II        SLC-2W
Payload is NASA's AURA scientific satellite

AUG-SEP		 10:00-13:00          Falcon I        SLC-3W
Payload is the Naval Research Laboratory's TacSat-1 satellite. The
launch window is fixed and does not change if the launch date changes.

SEP 18             ~03:22               Delta II        SLC-2W
Payload is NOAA N environmental satellite. Launch time is based on
informed speculation

OCT 18		 Unknown              Pegasus XL      Offshore
Payload is DART satellite

To be announced    To be announced      Minuteman III    ---
ICBM test launch (non-orbital). Glory Trip 184GM

To be announced    To be announced      Minuteman III    ---
ICBM test launch (non-orbital). Glory Trip 185GM

To be announced    To be announced      Minuteman III    ---
ICBM test launch (non-orbital). Glory Trip 186?

To be announced    To be announced      Peacekeeper      ---
ICBM test launch (non-orbital). Glory Trip 33PA?

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	         Southern California Astronomical Events
			          for 2004 May

		  Time
  Date	(PST/PDT)			Event
--------	---------	-----------------------------

MAY 4		13:33		Full Moon
Moon rises at sunset and sets at sunrise and is visible all night

MAY 11	04:04		Last Quarter Moon
Moon rises at midnight and sets at noon

MAY 14	14:00		Mercury Western Elongation
Elusive Mercury attains its greatest angular separation from the Sun
and is visible low in the east at dawn.

MAY 15-16	---		Dark Sky Weekend
Best time this month to observe faint objects. Amateur astronomers
will hold observing sessions from dark sites

MAY 18	21:52		New Moon
Moon passes between the Earth and the Sun and is invisible. Moon rises
at sunrise and sets at sunset

MAY 24	16:00		Planetary Conjunction
Mars and Saturn 1.6° apart

MAY 27	00:57		First Quarter Moon
Moon rises at noon and sets at midnight

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			           TIME FORMAT

All times in this newsletter are given in Pacific Time using a 24-hour
format similar to military time. Under this system, regular time is
expressed as follows:
                                            24-hour
		             Regular Time        Format
                    ---------------------   -------
			  12:00 a.m. (midnight)    00:00
			  6:00  a.m.               06:00
			  12:00 p.m. (noon)        12:00
			  6:00  p.m.               18:00

No distinction is made between Pacific Standard Time and Pacific
Daylight Time.

For assistance in converting military time to regular time, go to:

	http://www.spacearchive.info/military.htm

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Copyright © 2004 Brian Webb. All rights reserved. This newsletter may
be distributed in its entirety without restriction. Excerpts may be
reprinted elsewhere without permission if the source is clearly
identified as:

  Reprinted from Launch Alert (www.spacearchive.info/newsletter.htm)