# What's the largest single object payload ever lifted into space?

I am aware that the Saturn V is the largest rocket ever built and was capable of lifting more weight into space than anything that exists today. Modern rockets often carry several satellites up at once that together make up its full payload.

What I am wondering is: what is the largest single object ever lifted into space and what is its weight. Let's assume for this question that the LEM/CM or similar combinations are single multistage vehicles. Is the LEM/CM the largest yet, or is there something else?

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For the Apollo missions, the 3rd stage reached Earth orbit along with the LM (when present) and CSM (command and service module). – Keith Thompson Jan 22 at 21:33

Depending on your definitions, the contenders seem to be the US Space Shuttle, Buran, Apollo 17, or Skylab.

Apollo 17 + S-IVB translunar     143 t?
Discovery STS-82                 106 t
Polyus                            80 t?
Skylab                            77 t
Apollo 17 CSM/LM                  47 t


Skylab was 77 tons, launched as a single payload on a Saturn V (in fact, the station was converted from a Saturn V third stage).

The Apollo CM/LM stack was under 45 tons, but for the lunar missions, in low Earth orbit it remained attached to the Saturn's S-IVB third stage, which provided the fuel and engine for the translunar injection burn. The S-IVB burned a small amount of its fuel to get into LEO, but that left the combined translunar spacecraft massing over 115 tons.

The Apollos grew slightly in weight over the course of the program, as the launcher engines were uprated, confidence in safety margins improved, and more equipment was brought along. Apollo 16 and 17 were the heaviest, with 16 weighing a little more at launch, and 17 a little more in LEO (having used a bit less fuel getting there). Adding up the launch weights of components listed in Apollo By The Numbers, then subtracting the LES and the fuel used in the initial third-stage burn suggests an orbital mass over 140 tons.

The Space Shuttle orbiter masses over 68 tons dry, and carries a payload of up to 25 tons; its maximum takeoff weight ranged as high as 115 tons. I found a source giving Discovery's orbital mass as 106 tons for the STS-82 mission. As with the S-IVB, the orbiter is ambiguously part launcher and part payload.

The Soviet Energia booster was second to the Saturn V for payload-to-LEO, with approxmately 100-ton capability. It flew twice: once with the Polyus payload described in Puffin's answer, once with the Buran spaceplane. Astronautix manages to give two very different weight figures for Buran on a single page. It's either a little lighter or a little heavier than STS.

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Was skylab in its entirety, launched as a single payload? – Octopus Jan 22 at 21:28
So the possible candidates for the heaviest single object are: Apollo 9 through 17 (all the missions that launched a Lunar Module into Earth orbit) and Skylab 1. I can guess that Skylab was lighter than the Apollos (no LM, SM, or CM), but I'm not sure; the extra equipment might make up for that. Interesting question. – Keith Thompson Jan 22 at 21:32
Good grief, I forgot how heavy STS was. – Russell Borogove Jan 22 at 23:25
I'm not claiming it as the heaviest; that was just the only total mass to orbit figure I found. – Russell Borogove Jan 23 at 1:44
WP says '92s payload was 9.5t? This is why we can't have nice things. – Russell Borogove Jan 23 at 1:49

Following the theme of "depending on your definitions" one could also consider the Polyus spacecraft launched in 1987. The mass of the spacecraft was 80 tonnes.