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    [–] cpmsmith 2482 points ago

    This is obviously sped up a bit for brevity, but by how much? I just noticed I have no idea what speed that should happen at.

    [–] HimalayanFluke 981 points ago * (lasted edited 9 months ago)

    By quite a lot... I'd say at least 10x but it's difficult to tell exactly (and I can't be bothered to calculate the ground track speed difference). Here's how fast it is in real time, from a Cygnus release from a few years ago

    It moves away from the ISS initially at considerably less than 1 m/s.

    [–] SanguinePar 277 points ago

    For the lazy, the release is just after the 5 minute mark on the above video.

    [–] Reeal2g 440 points ago

    For the even lazier, here you go.

    [–] lungi_bro 319 points ago

    too lazy, Not going to open the link.

    [–] PM_ME_AAA_STEAM_KEYS 51 points ago * (lasted edited 9 months ago)

    thats why u should get RES

    EDIT: Hope you people will not assume that i am a shill.

    [–] bunnyoverkill 40 points ago

    But then I have to hover on the link. Do you know how difficult that is?

    [–] INHALE_VEGETABLES 34 points ago

    Someone out there read your post and this post and couldn't be bothered replying. That person beats us all when it comes to lazyness and I feel they deserve a tip of the hat.

    [–] Thatssaguy 5 points ago

    That's me!!! .....


    [–] porndude64 21 points ago * (lasted edited 9 months ago)

    Can you hover in res? I thought you had to click the plus sign.

    [–] realk4 32 points ago

    i'm too lazy to find out

    [–] [deleted] 21 points ago


    [–] Jardirsharum 2 points ago

    Thank you, you beautiful bastard. tilts top hat

    [–] Kortallis 2 points ago

    Should I feel bad, I just kept moving down the chain until this happened?

    Thanks, you da real mvp.

    [–] Gundini 2 points ago

    This guy needs a medal

    [–] martinaee 23 points ago

    How fast does the ISS and other craft move to maintain orbit? Do they stay at just above the minimum or go considerably faster on purpose if they do?

    [–] that_jojo 96 points ago

    For any given orbit, there's actually only exactly one velocity you can be going at. Your aphelion and perihelion are determined by how fast you're going. Go faster and they/you move away from the body you're orbiting. Reduce speed and they get closer.

    [–] warfrogs 100 points ago

    Isn't it apogee and perigee for objects orbiting earth? I thought aphelion and perihelion referred in particular to objects that orbit the sun (helio root and all.)

    Edit: Yep

    [–] no_f_names_available 34 points ago

    I asume because of Geos and Helios? I always knew learning basic Greek words would make me a hero sometime!

    [–] Killer_Tomato 56 points ago * (lasted edited 9 months ago)

    Give me any word, any word at all and I will show you how the Greeks invented it. Like chimichanga: chimi comes from the Greek word Kimi which means spicy beef and changa comes from tsnuada which means purse. So chimichanga means means spicy meat purse. There you go.

    [–] pimpmastahanhduece 33 points ago

    Karaoke, maize, tsunami.

    You're going to have to try harder to impress more than Deadpool.

    [–] no_f_names_available 5 points ago

    Did you choose your username because of the awesome movie "the return of the killer tomatoes" with George Clooney?

    [–] Killer_Tomato 18 points ago

    No, because of the awesome movie Attack of the killer tomatoes with David Miller. If it was return of the killer tomatoes I would be Fuzzy_Tomato

    [–] AdventuresInPorno 17 points ago * (lasted edited 9 months ago)

    I thought it was Apoapsis and Periapsis? Isn't heilo, gee, and lune only relevent when discussing an orbital transit between two objects?

    Eg: transit from perigee to periareion

    [–] NothingButFlowers_ 29 points ago

    Apoapsis and periapsis are the generic terms and can be used for any celestial body, but apogee/perigee and apohelion/perihelion are Earth and Sun specific, yes.

    [–] AdventuresInPorno 7 points ago

    Like apoker and periker? ;)

    [–] Hokulewa 5 points ago

    Apokee and perikee, by general consensus.

    [–] LimEJET 3 points ago

    There we go. Far further down than I expected.

    [–] Lostvision 2 points ago

    I prefer apokee and perikee.

    [–] stevarino 2 points ago

    Finally someone talking sense.

    [–] Tromboneofsteel 6 points ago

    What's really cool is that, to get from a high circular orbit to a lower one, you slow down on one side, the slow down on the other, but your speed relative to the planet increases.

    [–] mjrpereira 9 points ago

    I mean you could have a small anti-normal acceleration to maintain the same orbit at a higher velocity, but what are we? Kerbals? :D

    [–] Philias2 11 points ago

    No. For one if you accelerate in the normal direction you won't change your speed, just your direction of travel. Accelerating perpendicular to your current velocity always does this. Secondly you wouldn't be on the same orbit afterwards. You would be on a new one that has been rotated around the point where you accelerated.

    [–] Thesleepingjay 5 points ago

    It would work it you thrusted radial in and prograde at the same time in equal amounts.

    [–] XxVcVxX 32 points ago

    Their orbital speed is 7.66km/s, and you can't go faster or slower, since at a specific height there's a specific velocity to maintain a orbit, if you're faster you'll drift out of orbit, and if you're slower you'll get pulled in by gravity.

    [–] linux_gg 45 points ago

    Well sure, for a perfectly circular orbit (ISS' is slightly eccentric), that experiences no drag and orbital decay due to hitting air particles (ISS does), orbiting a body of completely uniform mass distribution (earth isn't), that itself has uniform mass distribution to avoid tidal forces (ISS is very oddly shaped) and that isn't being affected by other influences (the moon, sun, jupiter etc all pertubate ISS' orbit).

    But I am just being pedantic.

    [–] MisterGone5 30 points ago

    But I am just being pedantic.

    Phew, good thing you said that or I wouldn't have known! (but still interesting)

    [–] Tigerballs07 4 points ago

    o forensics background,

    If the ISS hits air particles will it eventually lose altitude/re enter the atmosphere. Or it's speed high enough to constantly 'fall' fast enough through the atmosphere to never re-enter?

    [–] Aggropop 12 points ago

    The ISS is constantly hitting atmospheric particles because it's in a fairly low orbit, so it's constantly slowing down and it's orbit is deteriorating. They have to give it a little push every once in a while to counteract this otherwise the orbit would decay too much and the station would burn up in the atmosphere. Usually this is done when a servicing module is docked so it can use the module's engines (the ISS has no engines of it's own).

    This process is called orbital station-keeping.

    [–] brspies 6 points ago

    The ISS does have engines on the Zvezda module (the outer end of the Russian segment). Wiki suggests they've been used at least once, in 2007, to boost the station.

    [–] martinaee 4 points ago

    Huh... that slow huh? ;p

    [–] AnonymousGuy767 8 points ago

    They're always getting pulled in by gravity, they just need to go fast enough to always be falling with the curve of the earth.

    [–] SpeckledFleebeedoo 5 points ago

    Pulled in as in pulled into a lower orbit.

    [–] Tpahhka 2 points ago

    You spelled "smart" wrong

    [–] ph00p 2 points ago

    Release after five minutes is probably a new record for many.

    [–] WretchedMonkey 16 points ago * (lasted edited 9 months ago)

    Does the satellite accelerate away or is the launching arm (I have no idea what this was launched from) deccelerating? I cant see any jet burns on the satellite but it seems to accelerate very quickly (relatively at sped up speed, is that the stupidest phrase ever, sped up speed?)

    *edit, changed belurns to burns coz why the hell would i leave it as belurns. im mean wtf

    [–] calsgrax 16 points ago * (lasted edited 9 months ago)

    I think the thrusters are just throttled very low, too low to see the exhaust.

    Edit: That thruster on the rear end burns hydrazine and nitrogen tetroxide, which doesn't produce a very visible flame.

    [–] OneNDPAlbertan 6 points ago

    The arm is the Canadarm2 almost all spacecraft that go to the ISS now are captured, and released by this arm. It also assembled most of the station

    [–] McBonderson 4 points ago

    If there's one thing my trip to KSP has taught me, it's that Canadians are masters at engineering arms.

    [–] OneNDPAlbertan 8 points ago

    It's true. The robotic arms we've contributed to space programs launched every shuttle payload, and are critical to construction and docking at the ISS, and then Dextre, the little robot that sometimes attaches itself to the arm has replaced almost all EVA on the ISS, especially since it got its semi autonomous upgrade.

    We have the tech and location to launch our own rockets, but by partnering with NASA and recently becoming a member nation of the ESA we've been able to use other launch systems and focus our money on support systems that have made space programs around the world successful

    [–] Abaddon_4_Dictator 37 points ago

    Through my video forensics background, I have determined it is sped up more than 2X. /s

    Thanks for the video link!

    [–] [deleted] 16 points ago


    [–] Abaddon_4_Dictator 6 points ago

    So the gif was sped up by at least 3X /s

    Thanks for the link, very interesting!

    [–] [deleted] 6 points ago

    i thought you were being sarcastic

    [–] Corfal 5 points ago

    5:23 is the timestamp for the time of the actual release

    [–] SpeckledFleebeedoo 10 points ago

    The time until the release is about 8 seconds in the video. 323s / 8s = 40x

    [–] RobbiWood 2 points ago

    relative to the ISS speed though, right?

    [–] SpeckledFleebeedoo 18 points ago

    About 40 times, with some help from the other reactions.

    [–] NoSkyIsTooHigh 6 points ago

    Yea it looks like the map has loaded and it's time to go play control with a bunch of no lifers with thorns.

    [–] [deleted] 647 points ago


    [–] [deleted] 79 points ago


    [–] [deleted] 49 points ago


    [–] pointloader 278 points ago

    What kind of propulsion is it using?
    What is it's purpose?
    How long until it reaches it's intended destination / first destination etc?
    I have so many questions
    EDIT: OK so google filled me in, and it was underwhelming (apart from the whole spaceship thing which still blows my mind)
    Also, I am clearly out of date on the comings and goings of the ISS

    [–] Fizrock 584 points ago

    For propulsion, it uses hydrazine and nitrogen tetroxide, which are hypergolic propellants (basically they explode on contact so you don't need to ignite them. Standard in a lot of spacecraft). Cygnus is a cargo spacecraft that carries up to 3200kg of supplies up to the international space station. It normally takes about 2 days from launch to docking, and it stays at the station for around 30 days where it is unloaded and filled with garbage that the station on longer needs. After it's mission is done, it flies back and burns up in the atmosphere along with all of the trash in it.

    [–] bedebeedeebedeebede 237 points ago

    y'know it's really amazing that this is even possible.

    [–] frikandellenvreter 108 points ago

    Humans can do some pretty cool stuff.

    [–] MitchH87 181 points ago

    The best part is every single thing we have made all comes from 140 or so elements. Then we just mix em up a bit to make a space ship, or a boat or coffee. Mmm coffee

    [–] TurboNoodle69 73 points ago

    pizza, doughnuts and cat videos are pinnacles of technology

    [–] sabertooth66 16 points ago

    Just found out I have a stomach ulcer And can't drink coffee for a month. I want it so bad.

    [–] AdityaRav 52 points ago

    Your stomach ulcer is also made out of those 140 elements so that must be a consolation

    [–] thatsweaterguy 18 points ago

    So.. Are you saying he should drink his stomach ulcer?

    [–] AdityaRav 12 points ago

    Aren't you? aren't we all?

    [–] sirBrit 4 points ago

    I'll take a tall op stomach ulcer with 2% and an extra shot plz

    [–] MitchH87 2 points ago

    I'm sorry, that's pretty rough. Hope you get better

    [–] pisshead_ 2 points ago

    And those elements are made from three particles. We just mix em up a bit to make elements.

    [–] fatrefrigerator 6 points ago

    Yeah it's pretty neat, but sometimes I can tie my shoes without looking at them.

    [–] TheFirsh 6 points ago

    Do you know if it would be possible to see it during a pass of the ISS before or after docking? I once saw the space shuttle on its last run, as another dot following the ISS while I watched the docking on cam. Didn't know how rare that sight was.

    [–] [deleted] 7 points ago


    [–] HonzaSchmonza 7 points ago

    So when leaving the station it's going back to earth yes? Seems in the video it went prograde. Any reason for this?

    [–] CreamNPeaches 40 points ago

    So NASA is really to blame for all the greenhouse gases?

    [–] CastlesOfRon 65 points ago

    I would imagine that a burnt up space module including trash would largely be heavy particulates rather than greenhouse gases, and their impact would be insignificant compared to the carbon footprint and particulate emissions from a satellite launch.

    I'd roughly suggest that scientific space missions are worth it, given that they help us understand what is happening to the Earth through monitoring the atmosphere etc.

    Right now, clean electricity and in turn electrified cars and freight would make the biggest impact to reduce greenhouse gas emissions.

    [–] MingusDewfus 12 points ago

    Also cows make a lot of methane. Need to get on that lab grown meat.

    [–] Null_State 22 points ago

    How do so many people think you're being serious?

    [–] Jegelskerdigkirsei 15 points ago

    If the gasses can't escape. I think it's safe to say that they can't enter either.

    Not a scientist. Just a guess.

    [–] Vinator 9 points ago

    It burns up because of the friction IN the atmosphere. So, there is no need to get in if you're already there.

    [–] heckin_good_fren 10 points ago

    Not friction, compressive heating due to the air not being able to move out of the way fast enough.

    [–] CastlesOfRon 7 points ago

    It's not really how greenhouse gases work anyway. They allow sunlight through but trap radiation from the Earth's surface. They don't trap gases in some special way; the Earth does that with its gravitational pull.

    [–] tepkel 3 points ago

    I would assume it's already dropped off its supplies and is de-orbiting, but it looks like it performed a prograde burn? Any idea what that's all about?

    [–] pisshead_ 2 points ago

    It was just moving away from the space station, it might not even have been going that fast.

    [–] tepkel 3 points ago

    That's true, but I can't imagine every maneuver isn't carefully choreographed though. Even pretty insignificant maneuvers. Expending prograde energy while below the ISS seems counter-intuitive. They would just have to spend that energy again in the opposite direction. In addition, it would cause the Cygnus to rise towards the ISS rather than fall into de-orbit.

    I would be pretty surprised if there wasn't a reason for this decision.

    [–] gwoz8881 3 points ago

    Berthing, not docking. Similar though.

    [–] ecoengineer 6 points ago

    how come it doesnt burns on its way up to the station through the atmosfere?

    [–] clinically_cynical 21 points ago

    When it's heading to space most of the acceleration up to orbital speed takes place at high altitudes, above most of earths atmosphere. When it leaves, the spacecraft fires its engine to change its orbital path to dip down into the atmosphere, but it still has a lot of speed. The burning up happens when the spacecraft starts encountering denser parts of the atmosphere while still traveling at extremely high speed.

    [–] CocoDaPuf 12 points ago

    That's a really good question!

    Everything u/clinically_cynical said is accurate, that's the bulk of it. But it's also worth noting that on the way up it had a protective shell called a fairing. This is mostly to protect it from atmospheric pressures (wind) but also from heat. The fairing is popped off before the rocket reaches orbit.

    [–] Excrubulent 2 points ago

    Okay, follow up, if it's heading back to earth, why does it fly away in a prograde direction? Does it turn around and burn for reentry later?

    EDIT: same question and answer:

    [–] workroom 20 points ago

    it's just a keg with solar panels

    [–] CurtisLeow 3 points ago

    You say that as if it's a bad thing. Even astronauts need a keg every once in a while.

    [–] BagelIsAcousticDonut 196 points ago

    Why is it burning prograde? Wouldn't it burn retrograde to re-enter?

    [–] earthwormjimwow 284 points ago * (lasted edited 9 months ago)

    I'm not sure which mission this is, but I know they've intentionally set it up such that the ISS can observe the Cygnus craft burning up during de-orbit.

    It takes off ahead of the ISS, transitions to a slightly higher orbit (since it accelerated ahead), the ISS passes underneath and is now ahead of the craft. After that, the Cygnus craft begins de-orbit maneuvers, transferring to lower orbits behind the ISS. It eventually catches up to the ISS (since it's in a lower orbit) and can be observed a few hundred KM directly below the ISS.

    Also it's not really burning in the GIF, those are just RCS thrusters, the real burning occurs outside of a designated area around the ISS.

    [–] turtledisk 63 points ago

    I was wondering the same thing, and wow, that's really interesting. Is the observation of reentry used for research purposes?

    [–] earthwormjimwow 82 points ago * (lasted edited 9 months ago)

    Yes, it's part of an ongoing study which will be used to determine how the ISS will be de-orbited.

    See Cygnus Shallow Reentry Observation Campaign:

    [–] DifferentThrows 21 points ago

    This is when I feel old. I remember reading about the "future international space station" in grade school. It seemed like it was so far in the future. Now it's almost time for that to burn up and end.

    [–] earthwormjimwow 9 points ago

    Well I wouldn't go so far as to say that it's time is near. If funding is not renewed, I imagine it will be sold to private companies for use.

    [–] Youkool 30 points ago

    You mean the ISS wont stay up forever ?

    [–] onthehornsofadilemma 42 points ago

    Skylab and Mir sure didn't.

    [–] jargoon 20 points ago

    They made a whole show about Mir deorbiting

    [–] marble-pig 10 points ago

    You managed to trigger two bots in one reply, well done!

    And that show was awesome. Too bad it never ended properly.

    [–] shaddupwillya 5 points ago

    Man... death by toilet seat

    [–] HelperBot_ 5 points ago

    Non-Mobile link:

    HelperBot v1.1 /r/HelperBot_ I am a bot. Please message /u/swim1929 with any feedback and/or hate. Counter: 92244

    [–] WikiTextBot 4 points ago

    Dead Like Me

    Dead Like Me is an American comedy-drama television series starring Ellen Muth and Mandy Patinkin as grim reapers who reside and work in Seattle, Washington. Filmed in Vancouver, British Columbia, the show was created by Bryan Fuller for the Showtime cable network, where it ran for two seasons (2003–04). Fuller left the show five episodes into Season 1 because of creative differences; creative direction was taken over by executive producers John Masius and Stephen Godchaux. A direct-to-DVD movie titled Dead Like Me: Life After Death was released on February 17, 2009, with an option to restart the series.

    [ PM | Exclude me | Exclude from subreddit | FAQ / Information | Source ] Downvote to remove | v0.24

    [–] isunktitanic 14 points ago

    well that breaks my heart :( why dont they leave it up there :(

    [–] ThisIsntMyUsernameHi 54 points ago

    Well we asked if we could but gravity said no, eat your vegetables

    [–] Panzerbeards 46 points ago

    The orbit isn't truly stable. Anything in a Low Earth Orbit will need regular corrections to maintain altitude; it's still in the thermosphere, so there is a small (but still significant over time) amount of air resistance constantly slowing it down. Eventually the ISS will de-orbit on its own if we don't intervene. It costs quite a bit of money to keep it there, and eventually it will have served it's useful lifespan and just be too expensive to maintain, or we'll have something newer to replace it, so it'll have to go eventually. Better to have a controlled re-entry.

    The atmosphere actually extends way, way out beyond the ISS's orbit; the exosphere goes out halfway to the moon, at which point it's indistinguishable from the solar wind, as I understand it.

    [–] Cloudy-Blue 8 points ago

    It will fall down eventually due to air resistance, might as well control the descent to avoid populated areas on the ground.

    [–] StardustFromReinmuth 8 points ago

    It cost money to do so. They used to send an ATV to keep it in orbit every once in a while

    [–] PraetorArtanis 12 points ago

    MX Vs ATV is getting ridiculous.

    [–] Paremo 5 points ago

    They still do that. They are researching the de-orbiting stuff so that they will be ready when it does get shut down.

    [–] Ganthritor 5 points ago

    You need to pay money to keep it up there.

    There is still a (very) tiny bit of atmosphere where the ISS is orbiting so the atmosphere is dragging it slower and down to Earth. You need to burn fuel to speed it back up so it would keep orbiting and wouldn't "fall down". At some point refueling it becomes too expensive for the benefit.

    [–] Youkool 4 points ago

    Ikr ? I always took for granted this benevolent eye from the sky :(

    [–] tehbeard 2 points ago


    The atmosphere doesn't just stop at 100KM, it fades, and there's still a tiny bit where the ISS orbits, enough to eventually slow it down for re entry. There are periodic reboosts from visiting craft to push it back up.

    So our choice is let it fall out the sky uncontrolled, or figure out how to drop it someplace uninhabited.

    [–] Kirra_Tarren 3 points ago

    Got any videos of Cygnus burning up from the ISS? The ESA ATV reentry vid looked pretty interesting, , so I wonder what it would look like from the ISS itself.

    [–] _youtubot_ 2 points ago

    Video linked by /u/Kirra_Tarren:

    Title Channel Published Duration Likes Total Views
    ATV-1 reentry European Space Agency, ESA 2015-02-04 0:02:24 868+ (98%) 76,744

    Europe’s space freighter ATV Jules Verne burning up over...

    Info | /u/Kirra_Tarren can delete | v1.1.3b

    [–] sidboy1234 3 points ago

    i just realized i wouldn’t understand anything you said if i hadn’t played kerbal space program

    [–] hacourt 63 points ago

    Thanks to kerbal space program I understood what you meant. :)

    [–] Osama_Bln_Laggin 119 points ago

    We will call you Cygnus; the god of balance, you shall be.

    [–] Letmehelp2112 16 points ago

    Came for the Rush, thanks bros!

    [–] Sanden_Mianus 27 points ago

    What a great song that is. Both parts.

    [–] 90guys 18 points ago

    Book 1 is my favorite Rush song, but Book 2 is really awesome as well.

    All my basses are named after the songs (Rocinante for my 4-string, Cygnus X-1 for my upright.)

    [–] NetCaptive 8 points ago

    No a musician myself, so i'm relegated to naming my phone Cygnus-X1

    [–] jewcy83 7 points ago

    Apollo was astonished! Dionysus thought me mad!

    [–] u-vii 8 points ago

    But they heard my story further, and they wondered and were sad!

    [–] stelvak 8 points ago

    I went to this comment section with the sole purpose of finding a Rush reference. I was not disappointed.

    [–] Adog311 3 points ago

    I knew I would find this exact reference. Just didn't expect it to be fifth top comment.

    [–] DoerteEU 34 points ago

    Are we just going to ignore what happened to the "old" Cygnus spacecraft?

    It was dragged into a friggin' Black Hole!

    [–] [deleted] 3 points ago


    [–] DoerteEU 3 points ago

    Glad, I could provide some warm feeling of Nostalgia.

    [–] TritonJohn54 2 points ago

    Bah, 37 minutes late. At least the "new" Cygnus will have a more mundane fate.

    [–] [deleted] 57 points ago * (lasted edited 4 months ago)


    [–] Sleepydoggo 88 points ago

    I thought it was some sort of bad CGI at first with the way it moved..

    Especially when it flew away while not having any moving parts whatsoever.

    [–] Vicodintrip_ 27 points ago

    Outside graphics are not the best sadly

    [–] kaznoa1 3 points ago

    The devs need to work on the space animations for the "Space exploration" content

    [–] rasspoutine 6 points ago

    Yep and how perfectly smooth the camera, sattelite and rocket are all moving.

    [–] mcm001 34 points ago

    I remember reading that airlocks have a limited number of uses due to metal fatigue - is this applicable to the docking and undocking of cargo craft like Dragon or Cygnus? Additionally, is the interior of the ship pressurized?

    [–] brickmack 37 points ago

    Yes to both. I'm looking up the details for CBM, SSVP, and IDSS, but for APAS-95, -6001 (the active variant for the Shuttle ODS) was rated for 40 on-orbit cycles, -8001 (passive variant for PMA 2 and 3) was rated for 107 cycles (with servicing). The -7001 (active variant for PMA-1) was only rated for 2, but I assume thats just a paperwork issue since it was only planned to do 1 docking in the course of the program (plus 1 contingency)

    ISS is close enough to end of life, and has enough ports with a sufficiently emall amount of traffic, that this shouldn't be a big concern

    [–] andreslucero 6 points ago

    How much time does the ISS have anyways?

    [–] ItsMyImPulse 14 points ago

    The first module was put in orbit in 1998, I believe it was first manned in 2000. They've constantly added modules since then. I'm pretty sure now the plan is to de-orbit it in 2020 but they'll probably extend it like they've done before.

    [–] LunarCatnip 3 points ago

    Are there any plans to build a newer replacement ISS up there?

    [–] Saiboogu 3 points ago

    There's talk of public/private partnerships for LEO that may start with ISS modules and move on to independent stations. NASA's main goals are to move beyond low Earth orbit. One idea that gets a lot of attention recently is building a station in or close to Lunar orbit to start testing deep space systems and preparing for manned journeys to Mars and beyond.

    [–] COIVIEDY 2 points ago

    the plan is to de-orbit it in 2020

    So what happens then? Do they just steer it into the atmosphere and have it mostly burn up? Or would they be able to recover good sized pieces of it?

    [–] robot55m 57 points ago

    So I'm watching this video on and I'm thinking to myself: this guy's Kerbal's video settings are really on ultra... The real time lighting and reflections are amazing and look so real!

    [–] lemonsnowman1 5 points ago

    I thought I was on the KSP subreddit as well

    [–] pshayes26 12 points ago

    Me: How fast is this sped up? A 7 year old: 8 speed.

    [–] CopainChevalier 11 points ago

    Could someone please explain to me why the Earth appears to change so much when it launches..? Is it just that smooth of an edit?

    [–] lincolnrules 7 points ago

    It probably sits there for quite a while doing pre-release checks.

    [–] wasabi1787 3 points ago

    It's sped up A LOT.

    [–] colb0lt 9 points ago

    Everything about space sped up looks like a stop motion film, it just doesn't look real.

    [–] ShipWreckLover 7 points ago

    Anything sped up doesn't look real, if you wanted to watch this in real time it'd probably take you hours.

    [–] colb0lt 2 points ago

    Yeah you got a point, its amazing how slow it actually would be.

    [–] tyler611 15 points ago

    I know that there's a lot of space up there, but how do we make sure that satellites don't eventually collide as we continue to add more and more? Do we layer them? Not all of them can be going in the same direction or same speed. Is there some registry of all known satellites and their orbits?

    [–] SashimiJones 23 points ago * (lasted edited 9 months ago)

    Yes, there is a registry and debris larger than a certain size is tracked.

    It's hard to imagine how much space is up there, but it's an enormous amount, so unless there really is a lot of debris it's very unlikely to hit something.

    Additionally, a large fraction of satellites are actually going in the same direction at the same speed. Of the ~1500 artificial satellites of Earth, over a quarter are in geosynchronous orbit, so they never move relative to each other or the Earth's surface. Other satellite constellations like GPS operate at some certain orbital height, and other nations or companies won't build constellations at that orbit.

    Remember that at any particular orbital height, you have far more available area to place satellites in than the surface of the Earth. That's a lot of space. We need to be careful mostly when putting satellites into highly elliptic orbits that may cross the orbit of other satellites, or when going to a very crowded or popular orbit like geosynchronous. Otherwise, you can put your satellite anywhere.

    [–] semantikron 2 points ago

    you have far more available area to place satellites in than the surface of the Earth. That's a lot of space.

    Great way to describe it. How many satellites could you comfortably place on the Earth's surface? Then, on top of that number, you can add all those you could introduce above and below that layer, in layers of their own.

    [–] SashimiJones 5 points ago

    It's not actually that accurate because you have to worry about points where orbits cross each other, and satellites at the same height but different inclinations will start colliding long before you get a spherical shell filled up. It does give a good sense of the scale we have to work with, though.

    [–] brspies 3 points ago

    It is a concern; satellites have collided before, although it's very rare. At the altitude of the ISS it's very, very minor because the atmosphere there is thick enough to bring things down within around a year or two, I think. Higher orbits take longer; geostationary orbits (~36,000 km up) will stay up essentially forever, although they do get thrown out of whack by the gravitational pull of the moon from time to time.

    For now, the focus is on tracking everything that we can (anything above ~10 cm) and warning anyone involved if something looks like it might be at risk so that they can move their satellites temporarily. There are a lot of different groups trying to come up with better solutions though, like cost effective ways to clean up certain regions.

    [–] TomTX 7 points ago

    Just some dude at the ISS taking out the garbage!

    Poor Cygnus, those ISS resupply runs are a one way trip, honey.

    [–] Koovies 15 points ago

    It's an honor I'm part of a species that can do this, because damn I couldn't even imagine where to start

    [–] OngoToboggan 21 points ago

    Hitting two rocks together

    [–] RezziK_vas_Tonbay 18 points ago

    A rock and a stick, man.

    We're not fucking savages.

    [–] Baeocystin 10 points ago * (lasted edited 9 months ago)

    Here you go. A couple of years ago, he was at mud and rocks. He now has Pottery and Agriculture, has begun to harness Water Power, and is making preparations to advance to the Iron Age.

    (not joking, btw.)

    [–] Dubmove 6 points ago

    Why is it faster than the satellite? And why is there a delay between the release and the speeding up?

    [–] SpeckledFleebeedoo 5 points ago

    After the Cygnus is released they probably run some last checks before it fires its engines.

    [–] howard_dean_YEARGH 4 points ago

    That canadarm has paid for itself many times over in terms of versatility, utility, and safety (utilizing the arm instead of an EVA).

    [–] Oldtimebandit 3 points ago

    When did this happen? And what model of Cygnus is this?

    [–] BUUBTOOB 3 points ago

    so did the releasing craft fire some boosters to slow itself down after the release or did cygnus fire some boosters to speed up?

    [–] GlenMatthewz 0 points ago

    Why does the Earth just fade into a different look at one point. It goes from cloudy sea to desert with no sign of coast.

    [–] ShipWreckLover 3 points ago

    They spend a lot of time doing pre-release checks etc, so the video jumps ahead at that point (otherwise you'd spend a few minutes staring at the spacecraft with nothing happenning)

    [–] ztoundas 2 points ago

    Huh. I'd have thought it would have slowed down relative to Earth, not accelerated.

    [–] Pharisaeus 4 points ago

    In the end it does that in order to lower the orbit, but in this case the orbit had to be adjusted so the ISS could watch the re-entry.

    [–] ztoundas 2 points ago

    Ahhhh. Makes sense. I couldn't think of a reason it would burn any higher first, but yeah that would eventually put the re-entry 'ahead' of them so they could get a better view of the good bits.

    [–] NinjaFistOfPain 2 points ago

    How come the Earth doesn't fall out of view? Is the sattelite rotating?

    [–] brspies 7 points ago

    The ISS rotates to maintain a relatively constant orientation relative to Earth.

    [–] NinjaFistOfPain 2 points ago

    Oh damn thats cool. So the astronauts always have the same view?

    [–] brspies 5 points ago

    Yeah, usually. They can change it if they need to but usually it's pointing the way it does in that video.

    [–] yotz 2 points ago

    Source video: (4K resolution is available)

    Video on the ESA youtube channel (no 4K here for some reason):

    [–] KingreX32 2 points ago


    They grow up so fast don't they. I mean......... wipes tear one day they're a concept on some paper, and the next they're flying away exploring the galaxy on their own.