# Star (rocket stage)

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. The number designations refer to the approximate diameter of the fuel casing in inches.
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 and survive potentially intact for millions of years.

## Star 13

The Star 13 (TE-M-458) is a solid fuel apogee kick motor. It was used on NASA's Anchored Interplanetary Monitoring Platform satellites. Several other versions were developed. Star 13D (TE-M-375) was used on the Syncom 1, Star 13A (TE-M-516) on LES 1/2, Aurora (P67-1), Orbiscal (P68-1), Lincoln Calibration Sphere 4, S3-2, Solrad 11A/B, SPX plume generator package, Freja, Meteor and Equator-S, Star C (TE-M-345-11/12) on AMSAT P3A and Star B (TE-M-763) on AMPTE-CCE payloads.
Thiokol Star 13 family :
| Name | Thiokol# | Mass (kg) | Mass (kg) | Prop. mass fract. | Imp. | Imp. | Burn (s) |
| Name | Thiokol# | Total | Empty | Prop. mass fract. | Spec., I$_{sp}$ (s) | Tot. (kgf-sec) | Burn (s) |
| Star 13 | TE-M-458 | 36 | 5 | 0.869 | 273 | 8,524 | 22 |
| Star 13A | TE-M-516 | 38 | 5 | 0.87 | 287 | 9,544 | 15 |
| Star 13B | TE-M-763 | 47 | 6 | 0.87 | 286 | 11,807 | 15 |
| Star 13C | TE-M-345-11/12 | 38 | 8 | 0.795 | 218 | 8,252 | |
| Star 13D | TE-M-375 | 35 | 6 | 0.81 | 223 | 7,799 | |
| Star 13E | TE-M-385 | 31 | 6 | 0.822 | 211 | 6,438 | |
| Star 13F | TE-M-444 | 40 | 7 | 0.83 | 240 | 9,608 | |

## Star 17

The Star 17 (TE-M-479) is a solid fuel apogee kick motor, first launched in 1963. It was used for payloads such as Radio Astronomy Explorer, SOLRAD and S3 satellites. The Star 17A (TE-M-521-5) version was used for orbit circularization on Skynet 1, NATO 1, IMP-H and IMP-J satellites.
Thiokol Star 17 family :
| Name | Thiokol# | Mass (kg) | Mass (kg) | Mass (kg) | Prop. mass fract. | Imp. | Imp. | Burn (s) | Length (m) |
| Name | Thiokol# | Total | Empty | Prop. | Prop. mass fract. | Spec., I$_{sp}$ (s) | Tot. (kgf-sec) | Burn (s) | Length (m) |
| Star 17 | TE-M-479 | 79 | 9 | 70 | 0.881 | 286 | 20177 | 18 | 0.98 |
| Star 17A | TE-M-521-5 | 126 | 14 | 112 | 0.903 | 287 | 32556 | 19 | 0.98 |

## Star 20 (Altair-3A)

The Star 20 (TE-M-640) is a solid fuel apogee kick motor, also known as Altair-3A. It was used as a second stage on an Atlas-E/F vehicle launching Stacksat. The TE-M-640 motor is similar to Altair 3 (FW-4S), and both are designated by NASA as Altair IIIA.
Thiokol Star 20 family :
| Name | Thiokol# | Mass (kg) | Mass (kg) | Prop. mass fract. | Imp. | Imp. |
| Name | Thiokol# | Total | Prop. | Prop. mass fract. | Spec., I$_{sp}$ (s) | Tot. (kNs) |
| Star-20-Spherical | TE-M-251 | 123 | 114.8 | 0.934 | 234 | 296.25 |
| Star-20 | TE-M-640-1 | 300.9 | 273.2 | 0.908 | 286.5 | 771.77 |
| Star-20A | TE-M-640-3 | 314.3 | 286.0 | 0.910 | 291.9 | 822.48 |
| Star-20B | TE-M-640-4 | 306.7 | 273.8 | 0.893 | 289.1 | 776.53 |

## Star 24

The Star 24 (TE-M-604) is a solid fuel apogee kick motor, first qualified in 1973. It burns an 86% solids carboxyl-terminated polybutadiene (CTPB)-based composite propellant. The "24" designation refers to the approximate diameter of the Titanium fuel casing in inches.
Thiokol Star 24 family :
| Name | Thiokol# | Mass (kg) | Mass (kg) | Mass (kg) | Prop. mass fract. | Imp. | Imp. | Burn (s) | Length (m) |
| Name | Thiokol# | Total | Empty | Prop. | Prop. mass fract. | Spec., I$_{sp}$ (s) | Tot. (kNs) | Burn (s) | Length (m) |
| Star 24 | TE-M-604 | 218.2 | 18.33 | 199.9 | 0.916 | 282.9 | 560.5 | 29.6 | 1.03 |
| Star 24A | TE-M-604-2 | 198 | 19 | 179 | 0.903 | 282 | 500 | | |
| Star 24B | TE-M-604-3 | 219 | 19 | 200 | 0.915 | 283 | 561.6 | | |
| Star 24C | TE-M-604-4 | 239.3 | 19.73 | 219.5 | 0.92 | 282.3 | 613.9 | 28.0 | 1.07 |

## Star 26

The Star 26 (Burner 2A or TE-M-442) is an upper stage motor used in Burner II stage of the Sandia Strypi IV vehicle introduced in 1965. The Star 26B (TE-M-442-1) variant was used on the Thor-LV2F Burner-2A launcher. Star 26C (TE-M-442-2) was used on the DOT sounding rocket.
Thiokol Star 26 family :
| Name | Thiokol# | Mass (kg) | Mass (kg) | Prop. mass fract. | Imp. | Imp. | Burn (s) |
| Name | Thiokol# | Total | Empty | Prop. mass fract. | Spec., I$_{sp}$ (s) | Tot. (kN) | Burn (s) |
| Star 26 | TE-M-442 | 268 | 37 | 0.86 | 220 | 39.10 | 18 |
| Star 26B | TE-M-442-1 | 261 | 23 | 0.91 | 272 | 34.63 | 18 |
| Star 26C | TE-M-442-2 | 264 | 32 | 0.88 | 272 | 35 | 17 |

## 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-based composite propellant with an average erosion rate of 0.0011 inches per second (0.028 mm/s).
It as used as a second stage on a version of the Atlas E/F rocket, launching the Solwind and Geosat satellites. 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. 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.
Thiokol Star-27 family :
| Name | Thiokol# | Mass (kg) | Mass (kg) | Prop. mass fract. | Imp. | Imp. |
| Name | Thiokol# | Total | Empty | Prop. mass fract. | Spec., I$_{sp}$ (s) | Tot. (kgf-sec) |
| Star 27 | TE-M-616 | 361 | 27 | 0.924 | 288 | 96986 |
| Star 27A | TE-M-616-1 | 336 | 27 | 0.919 | 288 | 89684 |
| Star 27B | TE-M-616-4 | 345 | 28 | 0.921 | 288 | 92296 |
| Star 27C | TE-M-616-5 | 333 | 28 | 0.918 | 288 | 88555 |
| Star 27D | TE-M-616-8 | 332 | 26 | 0.921 | 288 | 88668 |
| Star 27E | TE-M-616-9 | 331 | 26 | 0.921 | 287 | 88301 |

## Star 30

The Star 30 (TE-M-700-2) is a solid fuel motor, with the 30 representing the approximate diameter of the stage in inches. Different versions (A, B, C, E and PB) were used as an apogee motor for satellites such as G-STAR, Skynet 4, Koreasat or the HS-376 satellite bus. Star 30E was used by the ORBEX small orbital launcher. A Star 30 booster was also used on the CONTOUR comet probe.
Thiokol Star-30 family :
| Name | Thiokol# | Mass (kg) | Mass (kg) | Prop. mass fract. | Imp. | Imp. |
| Name | Thiokol# | Total | Empty | Prop. mass fract. | Spec., I$_{sp}$ (s) | Tot. (kgf-sec) |
| Star 30 | TE-M-700-2 | 492 | 28 | 0.943 | 293 | 136455 |
| Star 30A | TE-M-700-4 | 492 | 28 | 0.942 | 295 | 137095 |
| Star 30B | TE-M-700-5 | 537 | 32 | 0.941 | 293 | 148816 |
| Star 30C | TE-M-700-18 | 630 | 39 | 0.939 | 287 | 171002 |
| Star 30E | TE-M-700-19 | 667 | 45 | 0.932 | 291 | 182216 |
| Star 30PB | TE-M-700-20 | 543 | 38 | 0.931 | 292 | 148816 |

## Star 31 (Antares 1A)

The Star 31 (also known as Antares 1A or X-254) is a solid fuel motor, with the 31 representing the approximate diameter of the stage in inches. It had a thrust of 60.50 kN and a mass of 1225 kg. It was used as a stages of WASP, Scout X, Scout X-1, Blue Scout Junior, Blue Scout I, Blue Scout II, Scout X-1A and RAM B.

## Star 37

The Star 37 was first used as the engine for the Thor-Burner upper stage in 1965. The Burner I used the Thiokol FW-4 (TE 364–1) engine and the Burner II used the Thiokol (TE-M-364-2).
The "-37" designation refers to the approximate diameter of the titanium 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 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 2,350 pounds (1,070 kg), while the motor has been qualified for propellant off-loading to 2,257 pounds (1,024 kg).
A spin-stabilized or thrust-vectoring version of Star 37 is used as the final stage of the Minotaur V launch vehicle.
The Pioneer 10 & 11, and Voyager 1 & 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).
Thiokol Star-37 family :
| Name (Thiokol#) | Mass (kg) | Mass (kg) | Mass (kg) | Prop. mass fract. | Prop. | Thrust, vac. (kN) | Imp. | Imp. | Burn (s) | Length (m) | Remark |
| Name (Thiokol#) | Total | Empty | Prop. | Prop. mass fract. | Prop. | Thrust, vac. (kN) | Spec., I$_{sp}$ (s) | Tot. (kNs) | Burn (s) | Length (m) | Remark |
| Star-37 (TE-M-364-1) | 621.2 | 62.7 | 558.4 | 0.899 | Solid | 43.50 | 260.0 | 1584.46 | 42 | 0.80 | |
| Star-37B (TE-M-364-2) | 718.4 | 64.7 | 653.7 | 0.910 | Solid | ? | 291.0 | 1858.91 | ? | ? | |
| Star-37C (TE-M-364-18) | 1047.5 | 82.8 | 964.7 | 0.921 | Solid | ? | 285.5 | 2707.19 | ? | ? | |
| Star-37D (TE-M-364-3) | 718.4 | 64.7 | 653.7 | 0.910 | Solid | ? | 266.0 | 1858.91 | ? | ? | |
| Star-37E (TE-M-364-4) | 1122.7 | 83.1 | 1039.6 | 0.926 | Solid | ? | 283.6 | 2910.03 | ? | ? | Discontinued |
| Star-37F (TE-M-364-19) | 934.1 | 67.3 | 866.8 | 0.928 | Solid | ? | 286.0 | 2444.46 | ? | ? | Discontinued |
| Star-37FM (TE-M-783) | 1147.4 | 81.5 | 1065.9 | 0.929 | HTPB | 47.26 | 289.8 | 3051.35 | 63 | 1.69 | Developed and qualified for use as an apogee kick motor on FLTSATCOM |
| Star-37G (TE-M-364-11) | 1152.4 | 86.4 | 1065.9 | 0.925 | Solid | ? | 289.9 | 2988.36 | ? | ? | |
| Star-37N (TE-M-364-14) | 622.9 | 63.5 | 559.3 | 0.898 | Solid | ? | 290.0 | 1590.24 | ? | ? | |
| Star-37S (TE-M-364-15) | 711.4 | 53.4 | 658.0 | 0.925 | Solid | ? | 287.3 | 1872.43 | ? | ? | |
| Star-37X (TE-M-714-1) | 1150.0 | 82.8 | 1067.2 | 0.928 | Solid | 51.10 | 295.6 | 3047.69 | 60 | ? | |
| Star-37XE (TE-M-714-4) | ? | ? | ? | ? | Solid | ? | ? | ? | ? | ? | |
| Star-37XF (TE-M-714-6) | 953.2 | 67.7 | 885.4 | 0.929 | Solid | ? | 290.0 | 2542.03 | ? | ? | |
| Star-37XF (TE-M-714-8) | 882.5 | 67.1 | 815.4 | 0.924 | Solid | ? | 291.1 | 2342.74 | ? | ? | |
| Star-37XFP (TE-M-714-17/18) | 955.3 | 71.7 | 883.6 | 0.925 | HTPB | 38.03 | 290.0 | 2537.49 | 67 | 1.50 | Qualified as the orbit insertion motor for Boeing's Global Positioning Satellite (GPS), and as the apogee motor for the RCA SATCOM Ku-Band satellite. |
| Star-37Y (TE-M-714-2) | 1152.1 | 80.6 | 1071.4 | 0.930 | Solid | ? | 297.0 | 3118.20 | ? | ? | |

## Star 48

The Star 48 is a type of solid rocket motor developed primarily by Thiokol Propulsion, which was purchased by Orbital ATK in 2001. In 2018, Orbital ATK in turn was acquired by Northrop Grumman.
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 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 launch vehicles. Other launchers such as ULA's Atlas 551 have also incorporated the motor, but with lower frequency. On board the Space Shuttle, the complete stage (motor plus accessories) was referred to as the Payload Assist Module (PAM), as the Shuttle could only take satellites to low Earth orbit. 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 technique.
A non-spinning, thrust-vectoring 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, crossing Pluto's orbit in 2015 at a distance of 200 million kilometers. It is now set to leave the Solar System, traveling on a similar interstellar trajectory to its companion probe for the indefinite future.
In 2013 a Star 48GXV was tested for the Parker Solar Probe mission as the upper stage on an Atlas V 551 vehicle, but the development was canceled, in favor of a Delta IV Heavy / Star 48BV combination. The Star 48GXV boasted a carbon composite casing and nozzle, enabling it to operate at triple the chamber pressure of an ordinary Star 48. It also featured electro-mechanical actuators to gimbal the nozzle, along with digital flight controls.

## Star 63

The Star 63 is a solid fuel motor, with the 63 representing the approximate diameter of the stage in inches. Different versions exist: Star-63D (used on PAM-D2), Star-63DV and Star-63F. It was used to launch payloads from the Space Shuttle, and as stage on the Titan 34D and Delta 7925 rockets.
Thiokol Star-63 family :
| Name | Thiokol# | Mass (kg) | Mass (kg) | Prop. mass fract. | Imp. | Imp. | Burn (s) |
| Name | Thiokol# | Total | Empty | Prop. mass fract. | Spec., I$_{sp}$ (s) | Tot. (kNs) | Burn (s) |
| Star-63D | TU-936 | 3499.1 | 248.4 | 0.929 | 283.0 | 9043.23 | 118 |
| Star-63DV | | | | | | | 118 |
| Star-63F | TE-M-963 | 4590.4 | 325.9 | 0.929 | 297.1 | 12530.64 | 120 |