what really hppnd to Mars 96

From: ken.edgett@asu.edu (Ken Edgett)
Subject: what really hppnd to Mars 96
Date: Wed, 18 Dec 1996 08:33:27 -0700 (MST)

Mars Educators--

I finnally got ahold of some text that clears up the confusion
about what happened to Mars '96.  The object that hit the earth
Sunday evening, Nov. 17th was not the Mars craft itself...

Ken Edgett
Arizona Mars K-12

USSPACECOM release 41-96

November 29, 1996

Peterson AFB, COLO.-- U.S.  Space Command (USSPACECOM) has
developed new information indicating that the Russian Mars '96
spacecraft likely came down on Nov.  16 instead of Nov.  17 as
earlier reported.  Any debris surviving the heat of this re-entry
would have fallen over a 200-mile long portion of the Pacific
Ocean, Chile, and Bolivia.  We now believe that the object that
re-entered on Nov.  17, which we first thought to be the Mars '96
probe, was in fact the fourth stage of the booster rocket.

Confusion has surrounded key events and times in this mission,
including the last stages of the rocket burn, the separation of
the Mars '96 probe from the rocket, and the final re-entry into
the Earth's atmosphere of the booster and the probe.  USSPACECOM
has now completed an extensive post-event analysis that has led
to this new conclusion which supports Russian statements about
when their Mars '96 probe re-entered the atmosphere.  The area
where any debris surviving this re-entry could have fallen is
located along an approximately 50-mile wide and 200-mile long
path, oriented southwest to northeast.  This path is centered
approximately 20 miles east of the Chilean city of Iquique and
includes Chilean territory, the border area of Bolivia and the
Pacific Ocean.

The following is a chronological version of this space mission as
observed by USSPACECOM:

The Russians launched a SL-12 (Proton) four-stage rocket booster
from the Tyuratam space launch facility at 3:49 p.m.  EST on Nov.
16.  Aboard the booster was a spacecraft known as the Mars '96
probe destined for the planet Mars.

The USSPACECOM Space Surveillance Network (SSN) tracked the
rocket and boosters throughout the first three stages of launch,
and observed, recorded, and reported an object re-entering the
Earth's atmosphere at 7:49 p.m.  EST, Nov. 16.  Absent an
indication at the time of any problems with the Mars '96 probe,
U.S.  space observers ascribed the Nov.  16th event as the
booster stage re-entry--which would be normal for a multistage
rocket of this type.  The planned separation of the fourth stage
booster from the Mars '96 probe was not observed because it
occurred out of view of U.S. space sensors.  The USSPACECOM Space
Surveillance Network did track a single object associated with
this launch after monitoring the first three stages, which at the
time was believed to be the booster's fourth stage still attached
to the Mars probe.

On Nov. 17 it became apparent that the Mars '96 mission had not
achieved its intended trajectory to Mars.  USSPACECOM continued
to track in near-Earth orbit a single object thought then to be
the probe attached to the fourth-stage booster.  On that morning,
the Russians requested, through NASA, USSPACECOM assistance in
locating the Mars '96 probe.  USSPACECOM impact predictions were
forwarded to the Russians and Australians since initial
predictions indicated that the re-entry would take place over
Australia.  Updated analysis of tracking data and orbital
parameters placed the final impact of any surviving debris in the
Pacific Ocean 150-200 miles off the coast of Chile at
approximately 8:30 p.m.  EST.

On Monday, Nov. 18, the Russians announced that a failure on
board their spacecraft prevented the probe from achieving its
intended trajectory.  The Russians also said their probe had
likely re-entered the atmosphere on Nov. 16 between 7:30 and 8:30
p.m. EST.  Based on this information, USSPACECOM analysts began a
detailed review of all available data which ultimately led to our
refined conclusions.

USSPACECOM is not able to estimate what portion, if any, of the
Mars '96 spacecraft might have survived re-entry.  The United
States' interest in providing this information is to clarify
earlier preliminary U.S. reports that portions of the spacecraft
re-entered over the Pacific Ocean hundreds of miles off the
Chilean coast.  We are now convinced that any impact of the probe
that might have occurred on Nov.  16 would be within the area
described which includes portions of Chilean and Bolivian

The Russians are in the best position to address the materials on
board their spacecraft and whether any portion of the spacecraft
might have survived the heat of re-entry.  On Nov. 27, U.S.
officials shared this information with the Russians and provided
information to the governments of Chile and Bolivia concerning
the Nov.  16 Mars '96 re-entry over portions of their

DIRECTORATE OF PUBLIC AFFAIRS, Headquarters, U.S.  Space Command,
250 S. Peterson Blvd., Ste. 116, Peterson Air Force Base, CO
Phone:  (719) 554-6889 FAX:  (719) 554-3165 DSN:  692-6889
E-Mail:  noussppa@spacecom.af.mil