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--> YouTube-Generated Transcript <--
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

--> YouTube-Generated Transcript <--
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