Original Ranger

New Ranger

Block I

Block II

Block III

Objectives

Develop the engineering technology for spacecraft environment control, power conversion, attitude control, and communications to deliver scientific equipment in support of subsequent lunar and planetary missions. Produce scientific, engineering, and environmental data associated with deep space trajectories

Collect gamma-ray data both in flight and at the vicinity of the moon; obtain lunar surface photographs; transmit, after landing, lunar seismic and temperature data; experiment with trajectory error correction and terminal attitude maneuver; continue the development of basic spacecraft technology; perfect sterilization techniques.

Obtain television pictures of the lunar surface for the benefit of the scientific program and the U.S. manned lunar program. Pictures to be at least an order of magnitude better in resolution than any available from earth-based photography.

Spacecraft description

Hexagonal magnesium frame base, 1.5-m diameter. Two trapezoidal solar panels, diametrically opposed, hinged to base; full span 5.2 m. Magnesium vertical supports connected together with A.1 angles and tubes supporting superstructure containing scientific experiments and omni-antenna. Pointable high-gain antenna hinge-mounted to base. Attitude control jets mounted to base of frame. Overall height, 3.6 m.

Hexagonal magnesium frame base, 1.5-m diameter. Two trapezoidal solar panels, diametrically opposed, hinged to base; full span 5.2 m. Magnesium vertical supports connected together with magnesium angles and tubes. Block I superstructure replaced by lander capsule and equipment for gamma-ray and vidicon; omni-antenna atop capsule. Pointable high-gain antenna. Radar altimeter antenna. Midcourse propulsion in center of space frame. Retro- rocket in capsule assembly. Attitude jets on base of frame. Overall height, 3.6 m.

Hexagonal aluminum frame base, 1.5-m diameter. Two rectangular solar panels, diametrically opposed, hinged to base, full span 4.6 m. Television cameras mounted directly above base structure, with body-fixed optical axis. Pointable high-gain antenna hinge-mounted to base. Omni- directional low-gain antenna mounted at apex of superstructure. Midcourse propulsion located in center of hexagonal structure. Attitude control jets mounted to base of frame. Overall height 3.6 m

Weight, kg (lb)

Structures/mechanisms 60.8

Electrical (RF, TM, data) 27.0

Power 105.0

Attitude control (inert) 11.0

Controller-timer 4.4

Cabling 33.4

Friction experiment 9.5

Science (bus) 51.2

Expendables 4.4

Allowable launch weight 306.7 (674.7)

Structures/mechanisms 36.5

Electrical (RF, TM, data) 34.6

Power 42.5

Central computer 5.3

Attitude control (inert) 17.3

Cabling 19.5

Propulsion (inert) 10.9

Lunar capsule system 148.3

Science (bus) 13.7

Expendables 7.6

Average allowable launch weight 336.2 (739.6)

Structures/mechanisms 43.0

Electrical (RF, TM, data) 26.2

Power 57.8

Central computer 4.4

Attitude control (inert) 25.9

Cabling 15.6

Propulsion (inert) 10.4

Television system 173.0

Expendables 12.4

Allowable launch weight 368.7 (811.1)

Control

10 N₂ jets

3 gyros

2 primary sun sensors

4 secondary sun sensors

1 earth sensor

10 N2 jets

3 gyros

2 primary sun sensors

4 secondary sun sensors

1 earth sensor

12 N jets

3 gyros

2 primary sun sensors

4 secondary sun sensors

1 earth sensor

Electrical power

4340 Si solar cells/panel (2)

Panels: 26.7 x 74.4 x 184.4 cm

Total area: 1.8 m²

78.5 to 97 max. w/panel

Ag-Zn battery, 9000 Wh

Ag-Zn battery, 10 Wh

Note: no recharge capability for batteries

4340 Si solar cells/panel (2)

Panels: 26.7 X 74.4 X 184.4 cm

Total area: 1.8 m 2

78.5 to 97 max. w/panel

Ag-Zn battery, 1000 Wh

Note: battery rechargeable

4896 Si solar cells/panel (2)

Panels: 73.9 X 153.7 cm

Total area: 2.3 m2

100 w/panel

Ag-Zn battery, 1000 Wh (2) S/C

Ag-Zn battery, 1200 Wh (2) TV

Telecommunication

3-W L-band transponder

250-mW transmitter

Quasiomnidirectional low-gain antenna, parabolic high-gain antenna

Engineering data: 2 subcarriers, analog commutated, 1 sample per sec

Science data: 4 binary, 2 analog and 1 special subcarrier

3-W L-band transponder

50-mW L-band capsule transmitter

Quasiomnidirectional low-gain antenna

9 data subcarriers, analog commutated, sample rates of 0.1, 1.0 and 25 samples/s 2.5 and 25 bps. Video data at 2 kHz

3-W L-band transponder

60W L-band TV transmitter

Quasiomnidirectional low-gain antenna, parabolic high-gain antenna

Engineering data: 1 binary and 7 analog, commutated at 25., 1.0, 0.1 and 0.01 sample/s

TV data: 1 analog, commutated at 1 sample/s

Propulsion

None

Monopropellant hydrazine

222-N thrust

D V = 0.03 m/s to 43.9 m/s

I_sp= 230 s

Total impulse = 14,000 N_-s

4 jet-vane vector control

Monopropellant hydrazine

224-N thrust

D V = 0.03 m/s to 60 m/s

I_sp= 230 s

Total impulse = 23,500 N_-s

4 jet-vane vector control

Command

RTC-3 at 1 bps

SC-10

RTC-7 at 1 bps

SC-6

RTC-8 at 1 bps

SC-6

Note: Real-time commands (RTC) for momentary switch closures, stored commands (SC) for maneuver durations.