Venera

It’s not unusual for redundant satellites, rocket stages, or other spacecraft to re-enter the earth’s atmosphere. Usually they pass unnoticed or generate a spectacular light show, and very rarely a few pieces make it to the surface of the planet. Coming up though is something entirely different, a re-entry of a redundant craft in which the object in question might make it to the ground intact. To find out more about the story we have to travel back to the early 1970s, and Kosmos-482. It was a failed Soviet Venera mission, and since its lander was heavily over-engineered to survive entry into the Venusian atmosphere there’s a fascinating prospect that it might survive Earth re-entry.

A model of the Venera 7 probe, launched in 1970. — This model of the earlier Venera 7 probe shows the heavy protection to survive entry into the Venusian atmosphere. Emerezhko, CC BY-SA 4.0.

At the time of writing the re-entry is expected to happen on the 10th of May, but as yet due to its shallow re-entry angle it is difficult to predict where it might land. It is thought to be about a metre across and to weigh just under 500 kilograms, and its speed upon landing is projected to be between 60 and 80 metres per second. Should it hit land rather than water then, its remains are thought to present an immediate hazard only in its direct path.

Were it to be recovered it would be a fascinating artifact of the Space Race, and once the inevitable question of its ownership was resolved — do marine salvage laws apply in space? –we’d expect it to become a world class museum exhibit. If that happens, we look forward to bringing you our report if possible.

This craft isn’t the only surviving relic of the Space Race out there, though it may be the only one we have a chance of seeing up-close. Some of the craft from that era are even still alive.

Header: Moini, CC0.

Don’t look up! As of the time of this writing, there’s a decent chance that a Chinese Long March 5B booster has already completed its uncontrolled return to Earth, hopefully safely. The reentry prediction was continually tweaked over the last week or so, until the consensus closed in on 30 Jul 2022 at 17:08 UTC, give or take an hour either way. That two-hour window makes for a LOT of uncertainty about where the 25-ton piece of space debris will end up. Given the last prediction by The Aerospace Corporation, the likely surface paths cover a lot of open ocean, with only parts of Mexico and South America potentially in the crosshairs, along with parts of Indonesia. It’s expected that most of the material in the massive booster will burn up in the atmosphere, but with the size of the thing, even 20% making it to the ground could be catastrophic, as it nearly was in 2020.

[Update: US Space Command confirms that the booster splashed down in the Indian Ocean region at 16:45 UTC. No word yet on how much debris survived, or if any populated areas were impacted.]

Good news, everyone — thanks to 3D printing, we now know the maximum height of a dive into water that the average human can perform without injury. And it’s surprisingly small — 8 meters for head first, 12 meters if you break the water with your hands first, and 15 meters feet first. Bear in mind this is for the average person; the record for surviving a foot-first dive is almost 60 meters, but that was by a trained diver. Researchers from Cornell came up with these numbers by printing models of human divers in various poses, fitting them with accelerometers, and comparing the readings they got with known figures for deceleration injuries. There was no mention of the maximum survivable belly flop, but based on first-hand anecdotal experience, we’d say it’s not much more than a meter.

Humans have done a lot of spacefaring in the last sixty years or so, but almost all of it has been either in low Earth orbit or as flybys of our neighbors in the Sol system. Sure we’ve landed plenty of probes, but mostly on the Moon, Mars, and a few lucky asteroids. And Venus, which is sometimes easy to forget. We were reminded of that fact by this cool video of the 1982 Soviet landing of Venera 14, one of only a few attempts to land on our so-called sister planet. The video shows the few photographs Venera 14 managed to take before being destroyed by the heat and pressure on Venus, but the real treat is the sound recording the probe managed to make. Venera 14 captured the sounds of its own operations on the Venusian surface, including what sounds like a pneumatic drill being used to sample the regolith. It also captured, as the narrator put it, “the gentle blow of the Venusian wind” — as gentle as ultra-dense carbon dioxide hot enough to melt lead can be, anyway.

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