December 15 – Celebrating a Soviet Space Feat

Posted on December 15, 2016

The “Space Race” between the Soviet Union and the United States, back in the second half of the 20th Century, was super competitive and nationalistic – in other words, very “rah! rah! my country! – not nearly as nice as the current science-oriented cooperation between Russia, the U.S., and other space-faring nations.

But of course it was WAY preferable to war between our two nations!

And the Space Race did motivate some great accomplishments, as each nation tried to be first to do X, Y, or Z.

On this date in 1970, the Soviet Union became the first nation to successfully soft-land a spacecraft onto a planet. The spacecraft was Venera 7, and the planet was Venus.

Soft-landing is, of course, the opposite of crash-landing. The Soviet Union was first to crash-land a spacecraft on Venus, too – they accomplished that with Venera 3 in 1966 – and it was also the first nation to crash-land a spacecraft onto any body in space. (That first-ever was waaaaaaayyyyyy back in 1959, when a Soviet spacecraft intentionally crashed onto the Moon.)

Crash-landing is cool – scientists get all kinds of data and photos transmitted back until the actual moment of impact – but soft-landing is even cooler. With a soft-landing, the spacecraft can continue to take photos and gather and send information about everything from soil and air to temperature and other weather conditions. Also, of course, manned expeditions have to be soft landings.

But soft-landing isn't incredibly easy. The Soviets had to try four times to do a soft-landing on the Moon before they succeeded. And the Moon is way easier than Venus – it's closer, of course, and it has no atmosphere. Venera 4, 5, and 6 were apparently crushed by atmospheric pressure before they could impact Venus! 

Hoo, boy, that atmosphere of Venus! It's incredibly thick – about 90 times more mass pushing on every inch of the spacecraft than Earth's air does. And it's got a thick layer of sulfuric acid clouds – yes, the burn-the-skin, poisonous kind of acid! And it's really, really hot! The greenhouse effect we're nervous about here on Earth – often called global warming or global climate change – has really gone crazy on Venus, and day-time temperatures reach more than 460 degrees C (which is 860 degrees F!!!).

But after having several spacecraft being crushed by Venus's atmosphere before they could be crushed by slamming onto the ground, Soviet engineers were able to build a space probe that could withstand the pressure and the acidic clouds

and the heat. The Venera 7 parachute might not have worked perfectly, because the spacecraft hit the ground harder than desired. And the probe seemed to go silent as soon as it did the not-all-that-soft soft-landing. But after a few weeks Soviet scientists discovered that a really weak signal had been transmitted for 20 minutes and was sitting, waiting to be discovered, on their recordings. 

Our best guess is that, after landing, the probe had fallen on its side and therefore the medium-gain antenna was not able to send a strong signal to Earth. 

Thanks to Venera 7, humans learned for the first time just how hellish Venus is!

The photo above is from a much later U.S. spacecraft,
and the picture below is an artist's attempt to show us what Venus
would look like from the surface.

(By the way, back in the long-ago past, people hoped that there would be all sorts of lifeforms and maybe even human-like creatures living on Venus.)

Here is a strange video called "A Walk on Venus." Of course it is totally fiction -- humans haven't ever landed on another planet -- not yet, at least! -- although of course astronauts have walked on the Moon.

Also on this date:

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