The Star is a family of
US solid-propellant rocket
A solid-propellant rocket or solid rocket is a rocket with a rocket engine that uses solid propellants ( fuel/oxidizer). The earliest rockets were solid-fuel rockets powered by gunpowder; they were used in warfare by the Arabs, Chinese, Persia ...
motors originally developed by
Thiokol
Thiokol (variously Thiokol Chemical Corporation(/Company), Morton Thiokol Inc., Cordant Technologies Inc., Thiokol Propulsion, AIC Group, ATK Thiokol, ATK Launch Systems Group; finally Orbital ATK before becoming part of Northrop Grumman) was an ...
and used by many space propulsion and launch vehicle
stages
Stage or stages may refer to:
Acting
* Stage (theatre), a space for the performance of theatrical productions
* Theatre, a branch of the performing arts, often referred to as "the stage"
* ''The Stage'', a weekly British theatre newspaper
* S ...
. They are used almost exclusively as an upper stage, often as an
apogee kick motor
An apogee kick motor (AKM) is a rocket motor that is regularly employed on artificial satellites to provide the final impulse to change the trajectory from the transfer orbit into its final (most commonly circular) orbit. For a satellite la ...
.
Three Star 37 stages, and one Star 48 stage,
were launched on solar escape trajectories; fast enough to leave the Sun's orbit and out into interstellar space, where barring the low chance of colliding with debris, they will travel past other stars in the
Milky Way galaxy
The Milky Way is the galaxy that includes our Solar System, with the name describing the galaxy's appearance from Earth: a hazy band of light seen in the night sky formed from stars that cannot be individually distinguished by the naked eye. ...
and survive potentially intact for millions of years.
Star 24
The Star 24 (TE-M-640) is a solid fuel
apogee kick motor
An apogee kick motor (AKM) is a rocket motor that is regularly employed on artificial satellites to provide the final impulse to change the trajectory from the transfer orbit into its final (most commonly circular) orbit. For a satellite la ...
, first qualified in 1973.
It burns an 86% solids
carboxyl-terminated polybutadiene (CTPB) fuel.
[C.E.Carr II and D.W.Walstrum - Solid Rocket Propulsion for Small-Satellite Applications, Presented at Third Annual AIAA/Utah State University Conference on Small Satellites, Utah State University, Logan, Utah (26-28 September 1989) - Page 9]
/ref>
; Thiokol Star-24 family[
]
Star 27
The Star 27 is a solid apogee kick motor, with the 27 representing the approximate diameter of the stage in inches. It burns HTPB Hydroxyl-terminated polybutadiene (HTPB) is an oligomer of butadiene terminated at each end with a hydroxyl functional group. It reacts with isocyanates to form polyurethane polymers.
HTPB is a translucent liquid with a color similar to wax paper ...
fuel with an average erosion rate of 0.0011 inches per second.[ When used on the Pegasus air-launch rocket payloads are capable of leaving Earth orbit.][
A version of the Star 27, designated Star 27H, was used in the launch of the IBEX spacecraft.][IBEX]
/ref> The spacecraft had a mass of 105 kg by itself and together with its Star 27 motor, 462 kg.[ The Star 27H helped it get to a higher orbit, beyond Earth's magnetosphere.][
]
Star 37
The Star 37 was first used as the engine for the Thor-Burner
The Thor-Burner was an American expendable launch system, a member of the Thor rocket family. It consisted of a Thor missile, with one or two Burner upper stages. It was used between 1965 and 1976 to orbit a number of satellites, most commonly D ...
upper stage in 1965. The Burner I used the Thiokol FW-4 (TE 364-1) engine and the Burner 2 used the Thiokol (TE-M-364-2).
The "-37" designation refers to the approximate diameter of the fuel casing in inches; Thiokol had also manufactured other motors such as the Star-40 and Star 48. Internally, Thiokol's designation was TE-M-364 for early versions, TE-M-714 for later ones, and TE-M-783 for a special HTPB Hydroxyl-terminated polybutadiene (HTPB) is an oligomer of butadiene terminated at each end with a hydroxyl functional group. It reacts with isocyanates to form polyurethane polymers.
HTPB is a translucent liquid with a color similar to wax paper ...
model used for FLTSATCOM launches.
Subtypes are given one or more letter suffixes after the diameter number, or a trailing number (i.e., "-2") after the internal designation. Not surprisingly, the "T" prefix stands for Thiokol, and the following letter refers to the company division that developed the rocket motor. In this case, "M" refers to the Magna, UT Division. "E" refers to the Elkton, MD division.
The Star 37FM rocket motor was developed and qualified for use as an apogee kick motor on FLTSATCOM. The motor is a replacement for the Star 37E Delta, which has been discontinued. The Nozzle assembly uses a 3D carbon-carbon throat and a carbon-phenolic exit cone. Maximum propellant weight is 2350 pounds, while the motor has been qualified for propellant off-loading to 2257 pounds.
A spin-stabilized or thrust-vectoring version of Star 37 is used as the final stage of the Minotaur V
The Minotaur V is an American expendable launch system derived from the Minotaur IV, itself a derivative of the LGM-118 Peacekeeper ICBM. It was developed by Orbital Sciences Corporation, (now absorbed into Northrop Grumman Innovation Systems) ...
launch vehicle.
The Pioneer 10
''Pioneer 10'' (originally designated Pioneer F) is an American space probe, launched in 1972 and weighing , that completed the first mission to the planet Jupiter. Thereafter, ''Pioneer 10'' became the first of five artificial objects to ach ...
& 11, and Voyager 1
''Voyager 1'' is a space probe launched by NASA on September 5, 1977, as part of the Voyager program to study the outer Solar System and interstellar space beyond the Sun's heliosphere. Launched 16 days after its twin ''Voyager 2'', ''Voya ...
& 2 Propulsion Modules used Star 37E motors; each is now on a similar interstellar trajectory to its companion probe, and is set to leave the Solar System (except the Pioneer 11 stage, which is thought to have remained in solar orbit).
Star 48
The Star 48 is a type of solid rocket motor developed primarily by Thiokol Propulsion, which was purchased by Orbital ATK
Northrop Grumman Innovation Systems (NGIS) was a sector (business segment) of Northrop Grumman from 2018 through 2019. It was formed from Orbital ATK Inc. a company which resulted from the merger of Orbital Sciences Corporation and parts of Alli ...
in 2001. In 2018, Orbital ATK in turn was acquired by Northrop Grumman
Northrop Grumman Corporation is an American multinational aerospace and defense technology company. With 90,000 employees and an annual revenue in excess of $30 billion, it is one of the world's largest weapons manufacturers and military techn ...
.
The "48" designation refers to the approximate diameter of the fuel casing in inches; Thiokol had also manufactured other motors such as the Star 37 The Star is a family of US solid-propellant rocket motors originally developed by Thiokol and used by many space propulsion and launch vehicle stages. They are used almost exclusively as an upper stage, often as an apogee kick motor.
Three Star ...
and Star 30. Internally, Thiokol's designation was TE-M-711 for early versions, and TE-M-799 for later ones. Subtypes are given one or more letter suffixes after the diameter number, or a trailing number (i.e., "-2") after the internal designation. The "T" prefix stands for Thiokol, and the following letter refers to the company division that developed the rocket motor. In this case, "E" refers to the Elkton, MD division and the "M" stands for motor.
The most common use of the Star 48 was as the final stage of the Delta II
Delta II was an expendable launch system, originally designed and built by McDonnell Douglas. Delta II was part of the Delta rocket family and entered service in 1989. Delta II vehicles included the Delta 6000, and the two later Delta 7000 ...
launch vehicles. Other launchers such as ULA's Atlas 551 have also incorporated the motor, but with lower frequency. Onboard the Space Shuttle
The Space Shuttle is a retired, partially reusable low Earth orbital spacecraft system operated from 1981 to 2011 by the U.S. National Aeronautics and Space Administration (NASA) as part of the Space Shuttle program. Its official program ...
, the complete stage (motor plus accessories) was referred to as the Payload Assist Module
The Payload Assist Module (PAM) is a modular upper stage designed and built by McDonnell Douglas (now Boeing), using Thiokol Star-series solid propellant rocket motors. The PAM was used with the Space Shuttle, Delta, and Titan launchers and carri ...
(PAM), as the Shuttle could only take satellites to low Earth orbit
A low Earth orbit (LEO) is an orbit around Earth with a period of 128 minutes or less (making at least 11.25 orbits per day) and an eccentricity less than 0.25. Most of the artificial objects in outer space are in LEO, with an altitude never mor ...
. Because geostationary orbit is much more lucrative, the additional stage was needed for the final leg of the journey. On such missions, the stage was spin-stabilized. A turntable, mounted in the shuttle payload bay or atop the previous Delta stage, spun the PAM and payload to approximately 60 rpm prior to release.
Usually after motor burnout and just prior to satellite release the spin is canceled out using a yo-yo de-spin
A yo-yo de-spin mechanism is a device used to reduce the spin of satellites, typically soon after launch. It consists of two lengths of cable with weights on the ends. The cables are wrapped around the final stage and/or satellite, in the manne ...
technique.
A non-spinning, thrust-vectoring
Thrust vectoring, also known as thrust vector control (TVC), is the ability of an aircraft, rocket, or other vehicle to manipulate the direction of the thrust from its engine(s) or motor(s) to control the attitude or angular velocity of the ...
version of the Star 48 is available ("Star 48BV"), but much less common. A thrust-vectoring Star 48 is the final stage of the Minotaur IV+ launch vehicle.
A Star 48B motor used in the 3rd stage of the New Horizons probe was the first part of the New Horizons mission to reach Jupiter
Jupiter is the fifth planet from the Sun and the largest in the Solar System. It is a gas giant with a mass more than two and a half times that of all the other planets in the Solar System combined, but slightly less than one-thousandth t ...
, crossing Pluto
Pluto (minor-planet designation: 134340 Pluto) is a dwarf planet in the Kuiper belt, a ring of bodies beyond the orbit of Neptune. It is the ninth-largest and tenth-most-massive known object to directly orbit the Sun. It is the largest ...
's orbit in 2015 at a distance of 200 million kilometers. / Star 48BV combination.