The USSR flew three successful automated lunar sample return missions: Luna 16, Luna 20 and Luna 24. The probes landed on the Moon, collected samples, and started a small rocket with the samples back to Earth. The returned mass was very small (101 g, 30 g and 170 g, respectively).
From this pdf (Reconsidering Sputnik: Forty Years Since the Soviet Satellite) at NASA.gov referring to Sergei Korolev, the lead rocket engineer for the Sputnik project:
There were many debates on the shape of the first satellite, with most senior OKB-1 designers preferring a conical form since it fit well with the nose cone of the rocket. At a meeting ...
Using film from U.S. spy balloons to take pictures of the Moon
The photographic equipment used for the balloons was of no interest, but the film, created for shooting from high altitudes, was good: highly sensitive and strongly tanned, with a solution temperature of up to 50 degrees. Just what we need ...
Yes, they were aware. According to the Apollo transcript, Luna 15 was prominent in the daily news items that mission control shared with the crew.
In the transcript, timestamps are day/hour/minute/second; speakers are:
CC = CAPCOM
CDR = Commander (Armstrong)
LMP = Lunar Module Pilot (Aldrin)
CMP = Command Module Pilot (Collins)
23 hours into the mission (...
It's unlikely. They made no report of seeing it, although it was mentioned as a news item at several points during the mission. The sky is big, the moon's surface is big, rockets are fast, hypergolic propellant rocket plumes are very faint.
On Earth, most of visibility of objects coming from space is created by interaction with the atmosphere. As Moon has no atmosphere, an approaching space object would appear in a similar way to how on Earth we perceive orbiting objects: light reflected from the Sun at best. That is, under conditions that the object is large, reflective and properly positioned ...
Unlikely. Luna 15 left earth a little before Apollo 11 did. Although the "Cold War" was in full swing with intense rivalry, NASA took the then very unusual step of asking its enemy the Soviet Union if Luna 15 was going to interfere with the Apollo 11 trajectory. The Soviets, equally unusually for that time, replied it would not. Possibly the recordings of ...
Luna 16 was the first successful robotic probe to return sample from an extraterrestrial location to Earth for analysis. It did not return the first sample, that was done by Apollo 11, but it was the first time humanity successfully sent a robot into space to do such a task.
The illustration above and the text of the following were taken from multiple ...
"Натриевая комета" была создана на расстоянии трети расстояния до Луны - при этом обеспечивалась наилучшая видимость с территории СССР. Натрия заряжалось около 5 кг, хотя достаточно было и 1 кг. Общий вес системы испарения - 30-35 кг.
"The sodium comet" was created at distance of ...
There's a nice picture here but sadly unsourced and the scale is not given.
This one's a bit more detailed.
If this page is correct, the launch was at 06:39 and the cloud was emitted at 18:39, so T+12 hours. Still not a lot of detail though. (That last page says the sodium was emitted by the upper stage of the booster, not the probe. ...
First, restore the original image captions.
pivoting antennas - штыревые антенны - Whip antennas
ribbon antennas - ленточные антенны.
For what range of radio frequencies?
Частота передачи была равна 103 МГц, а частота приема — 183,6 МГц. Запасная система телеметрии работала на частоте 39,986 МГц. Космическая станция была оснащена шестью всенаправленными ...
Landing at night is a side effect of limited time and place options.
Возможности ракеты–носителя «Протон–К» позволяли доставить на поверхность Луны возвратную ракету массой не более 5 кг — этого было явно недостаточно для обеспечения перелета Луна–Земля, учитывая необходимость проведения коррекций траектории. В этой критической ситуации было найдено ...
Partial answer, just for Apollo
Note: Using metric specified in OP's comment of total program cost / total mass of rocks
In 2019 US dollars \$175,000,000,000 / 382 kg = \$458,115,113 / kg
IMHO that's a ludicrous metric though, implying nothing else was gained.
That appears to be a translation error.
This picture (figure 6.8) from Soviet Robots in the Solar System by Wesley T. Huntress, JR. and Mikhail Ya Marov shows that the flat surface at the left of the image in the question is an optical window. There are two semicircular aperture covers (shown open in the picture) which are labeled 'cover of illuminator' in ...
Almost certainly not.
First of all, only very bright stars were visible, when standing in the shadow of the LEM. The size of it was quite small, so most likely it would be too dim to view.
The deorbit burn took place at 15:47 UT on 21 July 1969. It crashed about 17° north latitude and 60° east. The difference in longitude is about 37 degrees, meaning it ...
I just saw a documentary about it. According to it the Apollo astronauts did know Luna 15 was near them and I think it said some of the astronauts finishing their moon walk and getting ready to leave saw it flying around as it did something like 42 orbits Of the moon while our astronauts were doing the walk. I’m not sure if they saw the crash but they def ...