Press Release

From Launch to Landing and Beyond, ATK Performs Key Roles on Mars Exploration Rover Missions

By SpaceRef Editor
June 11, 2003
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Advanced propulsion and
composite technologies developed by ATK (Alliant Techsystems)
perform key roles — from launch to landing — on two groundbreaking NASA
exploratory missions to Mars.

The first of two identical Mars Exploration Rovers (MER) lifted off
yesterday from Cape Canaveral Air Force Station, Fla. aboard a Boeing Delta II
7925 rocket powered by nine GEM-40 solid propulsion strap-on boosters which
provide additional thrust to the Boeing RS-27A main engine. ATK Thiokol
Propulsion manufactures the GEM family of boosters at its production facility
in Magna, Utah, continuing a tradition of flight support for Delta II missions
that began in 1990. ATK Composites, Clearfield, Utah, manufactures the
graphite epoxy cases for the GEM-40 boosters. The lightweight, filament-wound
cases are one-fifth the weight of steel.

“These MER missions help highlight the depth and breadth of ATK
capability,” said Paul David Miller, ATK chairman and chief executive officer.
“ATK is proud to support NASA with the capability needed to send the MERs on
their long journey, to assist in a safe touchdown and provide a platform for a
successful mission.”

Following burnout and separation of the GEM 40 boosters and the Delta
rocket’s liquid second stage, a STAR(TM)48B third-stage rocket motor produced
by ATK Elkton, Elkton, Md., fired for 90 seconds to deliver the MER spacecraft
into its required trajectory.

Journey to the Red Planet

Yesterday’s launch and a second MER launch scheduled on a Boeing Delta II
7925H rocket on June 25, will make their seven-month journey to the Red Planet
encased in a strong, lightweight composite lander structure shielding them
from the rigors of space travel and the impact of the Mars landing. Composite
Optics Inc. (COI), San Diego, Calif., built the lander structures and
performed significant design and analysis for the project. In addition, COI
manufactured the solar array substrates that provide power during the “cruise”
stage to Mars as well as the solar array substrates mounted on the MER to
provide power on the surface of Mars.

Descent, Landing and Beyond

In January 2004, the first MER spacecraft will land on Mars near the Gusev
Crater. Before landing, three solid propellant gas generators manufactured by
ATK will inflate airbags that cocoon the lander and rover assemblies. Three
ATK Rocket Assisted Deceleration (RAD) solid rocket motors will subsequently
fire to slow the spacecraft’s speed of descent to almost zero feet per second.
Throughout the descent, three ATK Transverse Impulse Rocket System (TIRS)
motors will compensate for lateral drift. The gas generators will continue
firing to keep the air bags inflated as the MER bounces and rolls to a stop.
The RAD and TIRS motors and gas generators were designed and fabricated by ATK
Elkton. ATK also provided the composite/titanium optical mast that houses the
MER’s navigational and panoramic cameras. Essentially acting as the “head”
and “neck” of the rover, the mast gives the rover the necessary height to see
greater distances on the Martian surface.

The second MER mission will use many of the same ATK subsystems as the
first rover mission with the exception of the Delta II rocket motors. To
compensate for the increased distance between the Earth and Mars, the second
launch vehicle will use ATK’s GEM-46 solid rocket motors, a larger derivative
of the highly reliable GEM 40.

ATK is a $2.2 billion aerospace and defense company with strong positions
in propulsion, composite structures, munitions, precision capabilities, and
civil and sporting ammunition. The company, which is headquartered in Edina,
Minn., employs approximately 12,000 people and has three business groups:
Aerospace, Precision Systems, and Ammunition and Related Products. ATK news
and information can be found on the Internet at www.atk.com .

The forecasts, projections, expectations, and opportunities for the
performance of the company’s systems on the MER missions in this news release
are “forward-looking statements” as defined in the Private Securities
Litigation Reform Act of 1995. Such forward-looking statements involve risks
and uncertainties that could cause actual results to differ materially from
anticipated results, including unforeseen delays in NASA’s Space Shuttle
program, changes in governmental spending and budgetary policies, economic
conditions, equity market returns, the company’s competitive environment, the
timing of awards and contracts, the outcome of contingencies, including
litigation and environmental remediation, program performance, and sales
projections, in addition to other factors identified in ATK’s filings with the
Securities and Exchange Commission.

SpaceRef staff editor.