4MV explained

4MV
Manufacturer:	NPO Lavochkin
Country:	Soviet Union
Preceded:	3MV
Operational:	1971-1989Engines: 1 KTDU-425 (Mars 2-3) 1 KTDU-425A (Post 1971) Fuel: UDMH/N2O4
Operator:	Soviet Space Program
Succeeded:	5VK
Power:	2 Solar arrays (Mars, Venera) 4 Solar arrays (Astron, Granat)

The 4MV planetary probe (short for 4th-generation Mars-Venus probe) is a designation for a common design used for Soviet unmanned probes to Mars and Venus.

It was an incremental improvement of earlier 3MV probes and was used for Mars missions 2 to 7 and Venera missions 9 to 16. Different versions of the bus exist, for example 4V-1, 4V-M and 4V-2.^{[1] [2]} The same base design was also used for earth-orbiting space observatories.^[3]

Design

The spacecraft bus has a height of 2.8m (09.2feet) and a solar panel span of 6.7m (22feet). The central section of the bus has a diameter of about 1m (03feet) and contained propellant. The main engine (KTDU-425) is encircled by a conical instrument compartment with the diameter of 2.35m (07.71feet) at the base.^[4] While Mars 2,3 and Kosmos 419 used the KTDU-425, 4MV buses after 1971 used the KTDU-425A).^[5]

Variants

• Mars M-71|3MS: Kosmos 419 (M-71|3MS No.170), Mars 2 (M-71 No.171), Mars 3 (M-71 No.172)^[6]
• Mars M-73|3MS|3MP: Mars 4 (M-73|3MS No.52S), Mars 5 (M-73|3MS No.53S), Mars 6 (M-73|3MP No.50P), Mars 7 (M-73|3MP No.51P)^{[7] [8]}
• Venera 4V-1: Venera 9 (4V-1 No.660), Venera 10 (4V-1 No.661), Venera 11 (4V-1 No.360), Venera 12 (4V-1 No.361), Venera 13 (4V-1M No.760), Venera 14 (4V-1M No.761)
• Astron: Astron^[9]
• Venera 4V-2: Venera 15 (4V-2 No.860), Venera 16 (4V-2 No.861)^[10]
• Granat: Granat^[11]

See also

• Soviet space program
• M-69
• Venera
• 3MV

Notes and References

1. Web site: Venera 9, 10, 11, 12 (4V1 #1, 2, 3, 4) . 2023-09-25 . Gunter's Space Page . en.
2. Web site: Venera 13, 14 (4V1M #1, 2) . 2023-09-25 . Gunter's Space Page . en.
3. Web site: 4MV. www.astronautix.com. https://web.archive.org/web/20230323162718/http://www.astronautix.com/4/4mv.html. 23 March 2023. live.
4. Web site: Venera-9 and 10. www.russianspaceweb.com.
5. Web site: KTDU-425 . https://web.archive.org/web/20161228034718/http://astronautix.com/k/ktdu-425.html . dead . December 28, 2016 . 2022-04-17 . www.astronautix.com.
6. Web site: Mars 2, 3 (Mars M71 #1, #2, #3) . 2023-09-25 . Gunter's Space Page . en.
7. Web site: Mars 4, 5 (Mars M73 Orbiter #1, #2) . 2023-09-25 . Gunter's Space Page . en.
8. Web site: Mars 6, 7 (Mars M73 Lander #1, #2) . 2023-09-25 . Gunter's Space Page . en.
9. Web site: Astron 1 . 2023-09-25 . Gunter's Space Page . en.
10. Web site: Venera 15, 16 (4V2 #1, 2) . 2023-09-25 . Gunter's Space Page . en.
11. Web site: Granat (Astron 2) . 2023-09-25 . Gunter's Space Page . en.