Apollo 10 Lunar Module Snoopy Was Placed in Solar Orbit May 23, 1969

Summary: Apollo 10 Lunar Module Snoopy was placed in solar orbit May 23, 1969, about two and one-half hours after docking with Command Module Charlie Brown.

With its descent stage already jettisoned, Apollo 10 Lunar Module Snoopy’s ascent stage approaches Command Module Charlie Brown, with lunar eastern limb (about 120 degrees east longitude) in background; red/blue diagonal line is the command module’s window; photograph by Command Module Pilot (CMP) John Young, Thursday, May 22, 1969; NASA image AS10-34-5112: Generally not subject to copyright in the United States, via NASA Image and Digital Library

Apollo 10 Lunar Module Snoopy was placed in solar orbit May 23, 1969, approximately two and one-half hours after its docking with Command Module Charlie Brown.

The National Aeronautics and Space Administration’s (NASA) Apollo 10 Press Kit, released May 7, 1969, described the Apollo human spaceflight program’s lunar module as “a two-stage vehicle designed for space operations near and on the Moon” (page 42). The module stood with a height of 22 feet 11 inches and a width of 31 feet. The module’s ascent stage measured 12 feet 4 inches in height and 14 feet 1 inch in diameter. The descent stage’s dimensions were a height of 10 feet 7 inches and a diameter of one inch. The lunar module was built by NASA contractor Grumman Aircraft Engineering Corporation in Bethpage, New York.

The lunar module’s spaceflight was a one-way trip. Neither of the module’s two stages was designed for a return to Earth. The Press Kit stated: “The LM is incapable of reentering the atmosphere.”

Apollo 10 was commanded by Thomas Patten Stafford (born Sept. 17, 1930), who was joined by John Watts Young (born Sept. 24, 1930) and Eugene Andrew Cernan (born March 14, 1934) as Command Module Pilot (CMP) and Lunar Module Pilot (LMP), respectively.

The mission’s three astronauts assigned the call sign of Snoopy to the lunar module. They selected Charlie Brown as the command module’s identifier.

Apollo 10 launched Sunday, May 18, 1969, at 16:49:00 Greenwich Mean Time/Coordinated Universal Time (11:49 p.m. Eastern Standard Time; 12:49 p.m. Eastern Daylight Time) as a lunar-orbital mission. Apollo 10 was designed as a dress rehearsal, absent a lunar landing, for Apollo 11, slated for launch in mid-July.

The Apollo 10 mission objectives required undocking of Apollo Lunar Module LM-4 from the Apollo Command and Service Module CSM-106 approximately 22 hours after the spacecraft’s insertion into lunar orbit. The 356.1-second, orbital-insertion maneuver began Wednesday, May 21, at 20:44:54 GMT/UTC (3:44 p.m. EST, 4:44 p.m. EDT). The firing of the service module’s propulsion engine cut off at 20:50:50 GMT/UTC (3:50 p.m. EST, 4:50 p.m. EDT).

The lunar module undocked from the command module Thursday, May 22, at 19:00:57 GMT/UTC (2 p.m. EST, 3 p.m. EDT). The Ground Elapsed Time (GET) was 98 hours 11 minutes 57 seconds (098:11:57) after Range Zero, the integral second before liftoff.

At 23:34:16 GMT/UTC (6:34 p.m. EST, 7:34 p.m. EDT; 102:45:16.9 GET), the ascent stage separated from the descent stage. The separation occurred at an altitude of 31.4 nautical miles above the lunar surface, according to freelance space writer Richard W. Orloff’s NASA-published Apollo by the Numbers (2000: page 76).

The ascent propulsion system (APS) began a 15.55-second firing at 23:44:02 GMT/UTC (6:44:02 p.m. EST, 7:44:02 p.m. EDT; 102:55:02.13 GET) to place the module’s ascent stage into an orbit with pericynthion, or nearest point to the lunar surface, at 46.5 nautical miles and apocynthion, or farthest point from the lunar surface, at 11.0 nautical miles. The ascent stage’s orbital insertion firing cut off at 23:44:17 GMT/UTC (6:44:17 p.m. EST, 7:44:17 p.m. EDT; 102:55:17.68 GET).

Lunar module ascent stage Snoopy docked with Command Module Charlie Brown on Friday, May 23, at 03:11:02 GMT/UTC (Thursday, May 22, at 10:11 p.m. EST, 11:11 p.m. EDT; 106:22:02 GET). Docking occurred at an altitude of 54.7 nautical miles, according to Orloff’s Apollo by the Numbers (page 77).

Closeout activities for Lunar Module Snoopy began Friday, May 23, at 03:31 GMT/UTC (Thursday, May 22, at 10:31 p.m. EST, 11:31 p.m. EDT; 107:20 GET). NASA’s Apollo 10 Mission Report, released August 1969, noted the “restowage of lunar module equipment for final jettison” and stowage of “debris, such as used food containers and other disposable items, that had collected in the command module over the 4-day period” inside Lunar Module Snoopy (9.9.8: page 9-19).

The ascent stage’s jettison occurred Friday, May 23, at 05:13:36 GMT/UTC (12:13 a.m. EST, 1:13 a.m. EDT; 108:24:36 GET). The ascent propulsion system’s (APS) firing to propellant depletion, which aimed to place LM Snoopy into a solar orbit, began at 05:41:05 GMT/UTC (12:41 a.m. EST, 1:41 a.m. EDT; 108:52:05.5 GET). The depletion burn was completed 249.0 seconds later, at 05:45:14 GMT/UTC (12:45 a.m. EST, 1:45 a.m. EDT; 108:56:14.5 GET).

NASA’s Apollo 10 Mission Post Launch Mission Operation Report No. 1, released May 26, 1969, noted, after the ascent stage’s jettison, that: “The crew visually acquired the LM descent stage on several occasions” (page 5).

The Mission Report described the crew’s last view of Lunar Module Snoopy. “Sequence films were made of separation, but after approximately 13 frames the lunar module disappeared into the sunlight and was only seen momentarily during the depletion firing” (9.9.8: page 9-19).

The Post Launch Mission Operation Report stated that Snoopy was tracked via the Manned Space Flight Network (MSFN) for “about 12 hours” after separation from Charlie Brown. “LM/MSFN communications were maintained until LM ascent stage battery depletion at about 120 hours GET.”

The takeaway for Apollo 10 Lunar Module Snoopy’s placement in solar orbit May 23, 1969, is that the Apollo 10 spacecraft’s ascent stage may still be circling the sun while the descent stage’s lunar orbit likely ended in a lunar surface impact.

Lunar Module 4, known in spaceflight as Snoopy, is being moved into position, Monday, Jan. 13, 1969, for mating with the Spacecraft Lunar Module Adapter (SLA) 13 in the John F. Kennedy Space Center’s Manned Spacecraft Operations Building (MSOB); NASA ID S69-17807: Generally not subject to copyright in the United States, via NASA Image and Digital Library

Acknowledgment

My special thanks to talented artists and photographers/concerned organizations who make their fine images available on the internet.

Image credits:

With its descent stage already jettisoned, Apollo 10 Lunar Module Snoopy’s ascent stage approaches Command Module Charlie Brown, with lunar eastern limb (about 120 degrees east longitude) in background; red/blue diagonal line is the command module’s window; photograph by Command Module Pilot (CMP) John Young, Thursday, May 22, 1969; NASA image AS10-34-5112: Generally not subject to copyright in the United States; may use this material for educational or informational purposes, including photo collections, textbooks, public exhibits, computer graphical simulations and Internet Web pages; general permission extends to personal Web pages, via NASA Image and Digital Library @ https://images.nasa.gov/details-as10-34-5112

Lunar Module 4, known in spaceflight as Snoopy, is being moved into position, Monday, Jan. 13, 1969, for mating with the Spacecraft Lunar Module Adapter (SLA) 13 in the John F. Kennedy Space Center’s Manned Spacecraft Operations Building (MSOB); NASA ID S69-17807: Generally not subject to copyright in the United States; may use this material for educational or informational purposes, including photo collections, textbooks, public exhibits, computer graphical simulations and Internet Web pages; general permission extends to personal Web pages, via NASA Image and Digital Library @ https://images.nasa.gov/details-S69-17807

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Marriner, Derdriu. “Jettisoned LM Snoopy Descent Stage Appeared Near Taruntius Crater.” Earth and Space News. Wednesday, May 11, 2011.
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Jettisoned LM Snoopy Descent Stage Appeared Near Taruntius Crater

Summary: Jettisoned LM Snoopy descent stage appeared near Taruntius Crater during Apollo 10 Command and Service Module (CSM) Charlie Brown’s lunar orbit 29.

Two-stage lunar module comprises ascent stage (above) and leggy descent stage (below); Lunar Module (LM) 4, moved for mating with the Spacecraft Lunar Module Adapter (SLA) in the John F. Kennedy Space Center’s (KSC) Manned Spacecraft Operations Building (MSOB), flew as the Apollo 10 mission’s LM Snoopy; Jan. 13, 1969; NASA ID S69-17810: National Aeronautics and Space Administration (NASA), Public Domain, via NASA Human Spaceflight

Jettisoned LM Snoopy descent stage appeared near Taruntius Crater on the moon’s near side during Apollo 10 Command and Service Module (CSM) Charlie Brown’s lunar revolution number 29.

Apollo 10 was designed as a “dress rehearsal,” minus the lunar landing, for lunar-landing mission Apollo 11, scheduled to launch approximately two months later, in July. Thomas Patten Stafford (born Sept. 17, 1930) commanded the three-astronaut mission. John Watts Young (born Sept. 24, 1930) and Eugene Andrew Cernan (born March 14, 1934) piloted the command module and the lunar module, respectively.

The astronauts gave Peanuts comic strip characters’ names to the mission’s modules. The command and service module was given the call sign of Charlie Brown. The lunar module was named Snoopy.

The Apollo 10 space vehicle launched on time Sunday, May 18, 1969, at 16:49:00 Greenwich Mean Time/Coordinated Universal Time (11:49 p.m. Eastern Standard Time; 12:49 p.m. Eastern Daylight Time) from central Florida’s John F. Kennedy Space Center. The National Aeronautics and Space Administration’s (NASA) Post Launch Mission Operation Report No. 1, released May 26, 1969, noted liftoff as “the fifth successive successful launch on-time of a Saturn V” three-stage rocket.

Three days later, on Wednesday, May 21, at 75 hours 55 minutes 54 seconds after liftoff (075:55:54.0 Ground Elapsed Time GET), the service propulsion engine commenced a 356.1-second firing to insert the spacecraft into lunar orbit. The lunar orbit insertion maneuver cut off at 076:01:50.1 GET (20:50:50 GMT/UTC; 3:50 p.m. EST, 4:50 p.m. EDT).

On Thursday, May 22, at 15:51 GMT/UTC (10:51 a.m. EST, 11:51 a.m. EDT; 09:02 GET), Commander Stafford and Lunar Module Pilot (LMP) Cernan transferred from Charlie Brown into Snoopy via the spacecraft’s docking tunnel. Command Module Pilot (CMP) Young remained in Charlie Brown. Undocking of the lunar and command modules occurred at 19:00:57 GMT/UTC (2 p.m. EST, 3 p.m. EDT; 098:11:57 GET).

The lunar module’s two stages were successfully separated during preparations for rendezvous with Charlie Brown. The separation, which occurred at 23:34:16 GMT/UTC (6:34 p.m. EST, 7:34 p.m. EDT; 102:45:16.9 GET), placed the descent stage into a temporary lunar orbit that would inevitably degrade into a lunar surface impact. The location of the Snoopy descent stage’s impact site is unknown.

Docking of the ascent stage and the command module occurred Friday, May 23, at 3:11:02 GMT/UTC (Thursday, May 22, at 10:11 p.m. EST, 11:11 p.m. EDT; 106:22:02 GET). The ascent stage was subsequently jettisoned, on Friday, May 23, at 05:13:36 GMT/UTC (12:13 a.m. EST, 1:13 a.m. EDT; 108:24:36 GET), for placement into a solar orbit.

During extensive landmark tracking and lunar feature photography from Command Module Charlie Brown, the three astronauts “visually acquired the LM descent stage on several occasions” (page 5). Encounters potentially posed safety threats, with the descent stage tumbling in and out of plane with the command module and moving above, below, behind and in front of the astronauts.

During the command module’s lunar orbit 29, the Apollo 10 astronauts espied Snoopy’s descent stage near the lunar near side’s Taruntius Crater. Taruntius lies on the northwestern edge of Mare Fecunditatis (Sea of Fecundity) in the eastern hemisphere and parents 15 satellite craters.

At about 132:16 GET, during the command module’s lunar orbit 29, Commander Stafford reported: “. . . . He’s getting awfully close. You could see the silver panels and -- there he is right down below us; he’s trying to cross the Taruntius . . . Yeah between Taruntius twins P and K. That rascal is right in-plane with us. . . .” (Apollo 10 PAO Mission Commentary Transcript, page 451/1).

At about 133:36 GET, Commander Stafford expressed the astronauts’ concerns about Snoopy’s proximity: “Yeah, I know it’s highly improbable a collision, but it’d sure ruin your whole day, if it ever happened” (453/1).

Mission Control Center’s (MCC) capsule communicator (CAPCOM) joked: “Okay. Old Snoop’s just a devoted old hound dog, Tom. He’ll probably be trying to follow you back home.”

Commander Stafford replied: “Just as long as that rascal doesn’t sniff too close” (453/3).

The takeaway for the jettisoned LM Snoopy descent stage’s appearance near Taruntius Crater on the moon’s near side is that the Apollo 10 mission’s three astronauts were concerned that the descent stage’s erratic tumblings posed a safety hazard, albeit “highly improbable,” to their spacecraft.

oblique view of Taruntius craters K and P, where Apollo 10 astronauts encountered jettisoned LM Snoopy descent stage; taken with 70mm Hasselblad by Apollo 10 mission, film magazine 31 (R); 70mm color film; NASA ID AS10-34-5134: National Aeronautics and Space Administration (NASA), No known copyright restrictions, via U.S. National Archives and Records Administration (NARA)

Acknowledgment

My special thanks to talented artists and photographers/concerned organizations who make their fine images available on the internet.

Image credits:

Two-stage lunar module comprises ascent stage (above) and leggy descent stage (below); Lunar Module (LM) 4, moved for mating with the Spacecraft Lunar Module Adapter (SLA) in the John F. Kennedy Space Center’s (KSC) Manned Spacecraft Operations Building (MSOB), flew as the Apollo 10 mission’s LM Snoopy; Jan. 13, 1969; NASA ID S69-17810: National Aeronautics and Space Administration (NASA), Public Domain, via NASA Human Spaceflight @ https://spaceflight.nasa.gov/gallery/images/apollo/apollo10/html/s69-17810.html

oblique view of Taruntius craters K and P, where Apollo 10 astronauts encountered jettisoned LM Snoopy descent stage; taken with 70mm Hasselblad by Apollo 10 mission, film magazine 31 (R); 70mm color film; NASA ID AS10-34-5134: National Aeronautics and Space Administration (NASA), No known copyright restrictions, via U.S. National Archives and Records Administration (NARA) @ https://nara.getarchive.net/media/as10-31-4574-apollo-10-apollo-10-mission-image-crater-taruntius-e-and-f-c6692a

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