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| 0:04 | · | hello it's Scott Manley here i |
| 0:06 | · | occasionally talk about spacecraft |
| 0:08 | · | falling back to Earth satellites that |
| 0:10 | · | burn up in the atmosphere and get |
| 0:11 | · | captured on somebody's you know |
| 0:13 | · | smartphone but uh we're actually |
| 0:16 | · | expecting a very old satellite to fall |
| 0:18 | · | back and this one is very different you |
| 0:21 | · | see 50 years ago March 31st 1972 the |
| 0:24 | · | Soviet Union launch a space mission and |
| 0:27 | · | we believe that this is a copy of a |
| 0:29 | · | veneer 8 this was another spacecraft |
| 0:31 | · | that was supposed to go to Venus |
| 0:33 | · | launched an amolia rocket it was common |
| 0:36 | · | at this time to build multiple copies of |
| 0:38 | · | spacecraft to increase the chances of |
| 0:40 | · | success and so like veneer 8 this was |
| 0:42 | · | supposed to go to Venus but something |
| 0:44 | · | went wrong and it ended up stuck in |
| 0:46 | · | Earth orbit now the Soviets would |
| 0:49 | · | quickly designate the spacecraft Cosmos |
| 0:51 | · | 482 and 50 years later one of the things |
| 0:55 | · | from that launch is still in orbit but |
| 0:58 | · | not for ver very much longer we think |
| 1:00 | · | this spacecraft is going to fall to |
| 1:02 | · | Earth in the coming days or weeks now |
| 1:04 | · | over the years there's been some |
| 1:06 | · | discussion speculation uh you know |
| 1:09 | · | debating as to the identity the size the |
| 1:12 | · | nature of this object and some people |
| 1:14 | · | claim that it's like the crew stage some |
| 1:16 | · | people think it's lander some people |
| 1:18 | · | think it's just debris but uh there's |
| 1:20 | · | one guy that wrote that an article uh |
| 1:23 | · | Dutch satellite observer uh Marco |
| 1:26 | · | Longbrook he's somebody that has a clue |
| 1:28 | · | and he thinks that it's only the descent |
| 1:30 | · | module and this is partly based on |
| 1:32 | · | looking at the light curves that show |
| 1:33 | · | that it doesn't change much uh and the |
| 1:36 | · | ballistic coefficient this is something |
| 1:38 | · | that is designed to go through |
| 1:40 | · | atmospheres with relatively low drag and |
| 1:43 | · | so the interesting part about that is |
| 1:45 | · | this spacecraft is very likely to |
| 1:47 | · | survive its re-entry into Earth's |
| 1:49 | · | atmosphere after all it was designed to |
| 1:52 | · | handle re-entry through Venus's |
| 1:54 | · | atmosphere and most spacecraft most |
| 1:56 | · | satellites that are de-orbiting they |
| 1:58 | · | don't do that they burn up high in the |
| 2:00 | · | atmosphere and put on a pretty light |
| 2:02 | · | show rather than drop dropping big |
| 2:05 | · | chunks of spacecraft onto the ground big |
| 2:08 | · | chunks of Soviet era spacecraft so yeah |
| 2:11 | · | Cosmos 482 blasted off from Bonur 4 days |
| 2:15 | · | after uh Veneera 8 right they probably |
| 2:19 | · | had basically the identical the same |
| 2:21 | · | ship design but unlike its sister ship |
| 2:23 | · | Cosmos 482 got stuck in this really |
| 2:26 | · | eccentric orbit so this orbit was like |
| 2:29 | · | 200 km by 9800 km a 52°ree inclination |
| 2:34 | · | and the reason for this is the stage |
| 2:37 | · | that was supposed to inject it into the |
| 2:38 | · | departure orbit stopped early either it |
| 2:41 | · | had a failure in its engines or its uh |
| 2:45 | · | timing system shut down early we're not |
| 2:47 | · | really clear but what happened was |
| 2:49 | · | spacecraft is stuck in this orbit now |
| 2:52 | · | western military space tracking networks |
| 2:54 | · | they are of course watching all these |
| 2:56 | · | launches they find a number of items |
| 2:58 | · | from this launch there's another stage |
| 3:00 | · | or two two stages in these eccentric |
| 3:03 | · | orbits there's some stages in low earth |
| 3:05 | · | orbit and over time these things have |
| 3:07 | · | dis disappeared but importantly about 90 |
| 3:10 | · | days after the initial launch the uh |
| 3:14 | · | spacecraft splits into two and this is |
| 3:17 | · | consistent with a Venusbound |
| 3:21 | · | spacecraft you know separating its |
| 3:23 | · | descent stage from the cruise stage in |
| 3:26 | · | anticipation of finally landing on Venus |
| 3:29 | · | and the interesting thing about this is |
| 3:32 | · | I guess that they kick themselves apart |
| 3:33 | · | at about you know maybe 10 m/s or less |
| 3:37 | · | not a huge amount of speed but because |
| 3:39 | · | it's in this highly eccentric orbit that |
| 3:42 | · | changes the orbit sufficiently that one |
| 3:45 | · | part burns up in |
| 3:47 | · | 1981 right so that lasts less than 10 |
| 3:50 | · | years whereas another part which is |
| 3:52 | · | about to come down that's lasted more |
| 3:54 | · | than 50 years so um that's why you know |
| 3:58 | · | that's the part that we've been |
| 3:59 | · | following all the other parts have gone |
| 4:00 | · | this is the last part from this |
| 4:02 | · | particular launch and that eccentric |
| 4:05 | · | orbit like as it comes down close to the |
| 4:07 | · | earth it's had a little bit of drag all |
| 4:09 | · | the time and what happens is the apogee |
| 4:11 | · | gets lower and lower faster than the |
| 4:13 | · | perigee the perigee has been pretty much |
| 4:14 | · | constant the whole time and as of like |
| 4:17 | · | tonight it's in a 380 by 154 km orbit so |
| 4:22 | · | it's come down from like 10,000 to 300 |
| 4:25 | · | and it's dropping by about 10 km per day |
| 4:28 | · | so it's going to come down it's |
| 4:31 | · | eventually going to get a near |
| 4:33 | · | circularized orbit and it's going to |
| 4:35 | · | fall somewhere over the Earth it'll plow |
| 4:38 | · | into the atmosphere if it's able to |
| 4:41 | · | handle re-entry it should come through |
| 4:43 | · | the hypersonic phase and maybe |
| 4:45 | · | decelerate to as slow as 70 m/s or about |
| 4:49 | · | 160 mph if we assume it's built the same |
| 4:54 | · | as Vaniraa 8 it would be designed with a |
| 4:56 | · | parachute but that's not likely to make |
| 4:59 | · | a difference because firstly that |
| 5:00 | · | parachute is designed for Venus's much |
| 5:03 | · | thicker denser atmosphere and also that |
| 5:06 | · | parachute almost certainly requires |
| 5:08 | · | battery power to operate and that will |
| 5:10 | · | be in short supply after 50 years in |
| 5:13 | · | space so this spacecraft is going to |
| 5:17 | · | slow down survive entry and then fall |
| 5:19 | · | through the atmosphere like a rock and |
| 5:21 | · | smash into the ground probably breaking |
| 5:23 | · | apart like an egg a giant 500 kg Soviet |
| 5:28 | · | space egg now we don't know exactly |
| 5:31 | · | where it will come come down because we |
| 5:33 | · | don't know when it will come down and |
| 5:35 | · | it's moving across the Earth at almost 8 |
| 5:37 | · | km/s so if you can't don't know when you |
| 5:40 | · | definitely don't know where odds are it |
| 5:43 | · | will be somewhere over the ocean because |
| 5:45 | · | most of the Earth is ocean but if it |
| 5:47 | · | comes down on land that could be |
| 5:49 | · | especially interesting it will smash |
| 5:51 | · | into the ground and you break apart it |
| 5:54 | · | will probably deliver a bunch of ancient |
| 5:55 | · | Soviet space technology to Earth and |
| 5:59 | · | there will no doubt be souvenirs and |
| 6:01 | · | stuff to collect it will be really cool |
| 6:03 | · | to see some of this stuff perhaps uh |
| 6:05 | · | looked at by museums or the worst sold |
| 6:08 | · | on eBay the problem is that we can't |
| 6:10 | · | really time the the descent exactly |
| 6:13 | · | because uh Earth's atmosphere is |
| 6:15 | · | constantly changing as the solar |
| 6:17 | · | activity goes up and down on a short |
| 6:19 | · | time scale the upper atmosphere can |
| 6:21 | · | balloon out very quickly and then sink |
| 6:23 | · | down over time now we do know that it |
| 6:26 | · | has to land somewhere between 50° north |
| 6:29 | · | and 50° 2° south because that is the |
| 6:32 | · | orbital inclination that is the only |
| 6:35 | · | place that it can access but that still |
| 6:38 | · | covers a huge part of the planet Earth |
| 6:41 | · | now the sister spacecraft Vanera 8 that |
| 6:44 | · | was has the distinction of being the |
| 6:47 | · | second spacecraft to land on Venus and |
| 6:50 | · | by the way while it was officially |
| 6:51 | · | called Vanera 8 there were actually 16 |
| 6:54 | · | prior probes that were sent to Venus but |
| 6:58 | · | only seven of which were successful most |
| 7:00 | · | of them were trapped in low Earth orbit |
| 7:01 | · | or worse and Cosmos 482 it was |
| 7:05 | · | presumably going to be called Veneer 9 |
| 7:07 | · | if it hadn't failed and got stuck in |
| 7:09 | · | orbit so yeah Vaneer 8 it uh flew it |
| 7:12 | · | launched on 27th of March and it got to |
| 7:15 | · | Venus uh 22nd of July 1972 it hit the |
| 7:19 | · | atmosphere decelerated and then |
| 7:22 | · | descended under parachute taking 55 |
| 7:24 | · | minutes or so to reach the surface |
| 7:26 | · | during this time it was doing science |
| 7:28 | · | all the way down for example it measured |
| 7:31 | · | light levels and it showed that the |
| 7:33 | · | light levels uh the way the light levels |
| 7:35 | · | worked it showed that there was a |
| 7:37 | · | definitive cloud layer that disappeared |
| 7:39 | · | after a certain altitude and they also |
| 7:41 | · | showed that the light levels on the |
| 7:43 | · | surface of the planet were sufficient |
| 7:45 | · | that they could actually take images |
| 7:47 | · | using cameras it had a gammaray |
| 7:50 | · | spectrometer on board which measured the |
| 7:52 | · | various radioactive elements and |
| 7:55 | · | isotopes in the surface of the planet |
| 7:56 | · | you know potassium uranium thorium and |
| 7:59 | · | then using their various ratios |
| 8:01 | · | geologists could determine that the |
| 8:03 | · | surface of Venus was probably consistent |
| 8:06 | · | with alkaline volcanic bassalts that we |
| 8:08 | · | find on Earth but Veneer 9 again it's |
| 8:12 | · | going to have the same technology on |
| 8:13 | · | board very likely it doesn't have |
| 8:15 | · | anything it's not going to have anything |
| 8:17 | · | dangerous on it might have some pyro |
| 8:18 | · | technics that are used to deploy like |
| 8:21 | · | parachutes and and stuff like that but |
| 8:24 | · | uh it's also by the way probably going |
| 8:26 | · | to have a fairly robust pressure shell |
| 8:28 | · | around it because it has to survive 80 |
| 8:31 | · | atmospheres of pressure and so if it |
| 8:33 | · | does fall into the ocean there's a |
| 8:36 | · | nonzero chance that this thing might |
| 8:38 | · | actually land and maybe float I'm not |
| 8:40 | · | sure about that because it's a 500 kg |
| 8:43 | · | object it just might be too compact and |
| 8:46 | · | too dense it might just sink if it did |
| 8:49 | · | sink it could sink pretty deep but then |
| 8:51 | · | again it is going to have to survive |
| 8:52 | · | landing at you know 160 m an hour but |
| 8:56 | · | yeah over the next few days we'll be |
| 8:58 | · | watching this if anything interesting |
| 8:59 | · | happens uh you know if we get any cool |
| 9:02 | · | photos that would be awesome if not uh |
| 9:04 | · | well that'll just be another you know |
| 9:07 | · | relic of the Soviet era getting lost i'm |
| 9:10 | · | Scott Manley fly safe |
