Slashdot Mirror

← Back to Stories (view on slashdot.org)

Two Big Rockets Launched Early Wednesday -- Then One Landed In High Seas (arstechnica.com)

Posted by BeauHD on from the party-in-the-sky dept.

Arianespace and SpaceX both launched rockets this morning between 7:25am ET (11:25 UTC) and 7:39am ET (11:39 UTC). The Ariane 5 ES rocket sent four Galileo satellites into medium Earth orbit (at an altitude of 22,922km) for the European Commission. "These satellites will form part of Europe's own global navigation system constellation," reports Ars Technica. As for SpaceX's Falcon 9 rocket, it launched from the West Cost to deliver 10 Iridium NEXT satellites into a polar orbit 625km above the Earth. Ars reports on how the launches went: Both rockets hit their instantaneous launch windows on Wednesday morning, with the Ariane 5 booster lifting off from Kourou, French Guiana under mostly sunny skies and the Falcon 9 rocket ascending from California through a thick fog layer. The upper stages of both rockets are now in their coast phases before deployment of their satellite payloads.

After the launches, attention turned toward SpaceX's attempt to recover its first stage and payload fairing. The atmosphere offshore, where the Just Read the Instructions droneship was stationed 235km away from the launch pad, had high wind shear. This means wind speeds and directions varied at different altitudes, making it a challenge to come back to the ground in a more or less straight path. This, combined with high seas, made for the "worst" conditions SpaceX has ever tried to land a rocket in, said launch commentator John Insprucker. The cameras on board didn't capture the landing clearly, but afterward SpaceX said the rocket did, in fact, make a safe landing on the droneship. Less certain was the fate of the payload fairing amid the poor weather conditions. "This is an experimental attempt; we're still learning how to catch a fairing out of the air," Insprucker said.

81 comments

  1. Sounds like a successful mission? by foxalopex · · Score: 4, Insightful

    It sounds like SpaceX's rocket successfully launched and they managed to recover the first stage. The Fairing is suppose to be a bonus recovery but it sounds like it was too windy to do successfully. Keep in mind the first stage actually has rocket power so it has some sort of control over where it is suppose to end up. The Fairing sounds like a huge piece of metal with a parachute. Good Luck catching that in random winds.

    1. Re:Sounds like a successful mission? by Bruce+Perens · · Score: 4, Informative

      The fairing has a steerable parachute. It's as big as a bus. They didn't manage to get the ship under it, but "they saw it come down".

      --
      Bruce Perens.
    2. Re:Sounds like a successful mission? by Rei · · Score: 3, Informative

      It's not just the grid fins and landing burns that make the first stage easier. The rocket does a boostback burn and a reentry burn, both of which help pointpoint where the rocket will end up. The fairing does no burns; the only control over where it will be when its parachute deploys is when it separates and the trajectory of the upper stage at the time. Errors in precision high up are amplified as the fairing descends and enters the atmosphere.

      The terminal guidance with the parachute and catching that with a boat is yet another problem on top of that. At least the parachute slows the descent, giving the boat more time to position itself.

      --
      "Lock and load, Brides of Christ!"
    3. Re:Sounds like a successful mission? by Bruce+Perens · · Score: 2

      Boostback is optional. Yesterday there was only enough fuel for retro and landing burn, and the re-entry was ballistic.

      --
      Bruce Perens.
    4. Re:Sounds like a successful mission? by Brandano · · Score: 1

      Makes me wonder why they don't try to snatch it with a grapple equipped helicopter, like they did with film canisters from spy satellites many years ago. I understand that it's a pretty large and heavy part (800Kg, I believe), but there should be helicopters that can manage that sort of maneuver, and then drop the load on a much smaller net before landing on their own barge.

    5. Re:Sounds like a successful mission? by Brandano · · Score: 1

      I think the fairing also has some manoeuvring nozzles added, mainly for the early re-entry phase control.

    6. Re:Sounds like a successful mission? by TheCastro1689 · · Score: 1

      Maybe it sinks too fast or gets filled with water and becomes too heavy.

    7. Re: Sounds like a successful mission? by c6gunner · · Score: 1

      How did you manage to misunderstand the word "catch"?

    8. Re:Sounds like a successful mission? by torkus · · Score: 1

      https://www.instagram.com/p/Bf...

      No, it floats apparently. But they'd rather catch it then have to fish it out of the (saltwater) ocean.

      I'm sure there's economic sense to it or they wouldn't try. $6mm isn't chump change to throw away on each mission and i'm guessing saltwater refurb costs > catchers mitt operation.

      --
      You can get rich if you own a politician, but you have to be rich to buy one in the first place.
    9. Re:Sounds like a successful mission? by Bruce+Perens · · Score: 2

      The film return capsules were much smaller and fell slowly, so that it could be hooked with a propeller plane that wasn't in a suicide dive. The fairing is 100 times larger and falls faster. Getting the helicopter that far out to sea is a problem. It runs out of fuel. You need a carrier ship anyway. So, they are trying it with just the ship.

      --
      Bruce Perens.
    10. Re:Sounds like a successful mission? by cjameshuff · · Score: 1

      A large helicopter, with pilot trained for such operations and insurance to cover the risks involved, and a separate ship for it to operate from would all be quite expensive. With the film canisters, it didn't matter if it cost a few million to arrange their recovery, but with these, the whole point is to save a few million.

    11. Re:Sounds like a successful mission? by Agripa · · Score: 1

      https://www.instagram.com/p/Bf...

      No, it floats apparently. But they'd rather catch it then have to fish it out of the (saltwater) ocean.

      I'm sure there's economic sense to it or they wouldn't try. $6mm isn't chump change to throw away on each mission and i'm guessing saltwater refurb costs > catchers mitt operation.

      The lower launch cost from recovering the first stage makes the loss of the payload fairing a larger part of the launch costs so there is more incentive to recover it.

  2. Both Landed in High Seas by Bruce+Perens · · Score: 5, Insightful

    Both the Arianne 5 first stage and the Falcon 9 first stage landed in high seas. The Arianne sank to the bottom of the ocean to become an interesting reef for fish, as is their usual procedure. The Falcon 9 landed on a barge and will probably be reused. Yesterday's Falcon 9 recovery was pretty "hot" due to its lifting the heaviest satellite (other than space stations) there is to a substationary orbit, and it's not clear there is a 10-flight life in that booster without refurbishment. I've not yeard about the expected life of the booster in today's mission, but I'd assume 10 without refurbishment.

    --
    Bruce Perens.
  3. a cost compare by Anonymous Coward · · Score: 2, Interesting

    Ariane cost: $165-220M per launch, 16,000 kg to LEO.
    Falcon 9 cost: $50M per launch (2018), 22,800 to LEO.

    Taking the middle of the Ariane cost, it is $12,000 per KG to LEO. The F9 is $2200 per KG to LEO.

    1. Re:a cost compare by bobbied · · Score: 1

      Ariane cost: $165-220M per launch, 16,000 kg to LEO. Falcon 9 cost: $50M per launch (2018), 22,800 to LEO.

      Taking the middle of the Ariane cost, it is $12,000 per KG to LEO. The F9 is $2200 per KG to LEO.

      Not to doubt you, but where did you find those numbers?

      --
      "File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
    2. Re:a cost compare by Anonymous Coward · · Score: 3, Informative

      Not to doubt you, but where did you find those numbers?

      Sorry, i should have put the sources. All numbers sourced from wikipedia, but there are many other sources around the net too. Sidebars on the right:

      Ariane 5
      Falcon 9

    3. Re:a cost compare by nojayuk · · Score: 3, Informative

      The Ariane 5 that launched four Galileo satellites yesterday is the ES variant, capable of putting about 21 tonnes into LEO. It's only flown that particular profile for ATV service missions to the ISS. This is the second ES-variant Galileo mission flown, putting a carrier with four satellites in elliptical orbit which is then circularised at GPS altitude (about 20,000km). Originally the Galileo satellites were being launched two at a time by Soyz-Fregat rockets but one launch went wrong and ESA decided to take the rest of the launches "in-house". It worked out cheaper to fly four satellites at a time on the heaviest-lift variant of the Ariane V compared to two at a time on the less-capable ECA variant.

      As for the Falcon 9 FT it can only, IIRC, deliver 20-odd tonnes to LEO if it flies without recovery in mind -- no landing legs, no first-stage fuel reserve for landing etc. This makes for a more expensive launch cost.

    4. Re:a cost compare by Bruce+Perens · · Score: 3, Interesting

      Falcon 9 block 5 can lift 25 tons to LEO with recovery. Block 4 could only do that if expended.

      --
      Bruce Perens.
    5. Re:a cost compare by Anonymous Coward · · Score: 0

      More like you've got the full 7, but your partner only needs 3.

    6. Re:a cost compare by Anonymous Coward · · Score: 0

      More like you've got the full 7, but your partner only needs 3.

      But Bruce, Ariane has lifted a number of 20 ton payloads to LEO.
      Spacex cliams to be cheaper, but nobody in the 20 ton class gives a shit about Falcon9?

      BTW, why are you posting anonymous coward Bruce? Embarrassed that your schlong is only 3 inches?
      3 inches is plenty in the Musk/pedo circles I've been told.

    7. Re:a cost compare by Ksevio · · Score: 1

      Probably because there isn't much of a market for payloads that large. The last one was in 2015 and that was likely contracted before SpaceX even was capable.

    8. Re: a cost compare by c6gunner · · Score: 1

      Falcon 9 block 5 can lift 25 tons to LEO with recovery. Block 4 could only do that if expended.

      Nonsense. Block 5 can do 22 tonnes in expendable mode, or about 13 tonnes with recovery.

      No clue where you are getting your numbers, but the whole idea that block 4 can lift significantly more than block 5 is just wrong. The major improvements between block 4 and block 5 had to do with making the rockets more durable and easier to reuse; lift capacity was essentially unchanged.

    9. Re: a cost compare by Bruce+Perens · · Score: 1

      That was in short tons, and the stage-1-recoverable weight to LEO would be 22.8 tonnes for block 5.

      SpaceX keeps changing the figures here as they upgrade, you can look at the older versions on the Wayback Machine.

      While block 4 quoted a 22 tonne mission in expendable mode, block 5 does all missions in recoverable mode and quotes that same weight for a recoverable mission. There is a quote here of Musk on the engine difference: The most important part of Block 5 will be operating the engines at their full thrust capability, which is about 7 or 8% - almost 10% - more than what they currently run at. Note that "full thrust" has been used to refer to increases in thrust twice, with different figures each time.

      So, block 5 is about twice the power of the original Falcon 9. I think the quoted weight to LEO might be with no boost-back burn, just ballistic re-entry with a retro and landing burn, as they did for the Telstar 19v the other day (to a substationary orbit).

      --
      Bruce Perens.
    10. Re: a cost compare by c6gunner · · Score: 1

      While block 4 quoted a 22 tonne mission in expendable mode, block 5 does all missions in recoverable mode and quotes that same weight for a recoverable mission.

      No, it doesn't; the page you linked to gives performance and capability data and simply doesn't differentiate between the two modes. If you had clicked on the "pricing" link you would have seen that the following page lists a "standard payment plan" at $62 million, limited to 5.5 mT to GTO. This is consistent with Block 4 figures; it's the maximum lift of the rocket in reusable mode.

      Below that they list a maximum lift of 8.3 mT to GTO, which, again, is consistent with Block 4. But they don't give a price for the maximum.

      Putting the two together, the rocket can lift 5.5 tonnes to GTO in reusable mode, and 8.3 tonnes in expendable. Extrapolating that down to LEO gives the same numbers I quoted earlier; 22 tonnes expendable, or 13 tonnes reusable.

      There is a quote here of Musk on the engine difference: The most important part of Block 5 will be operating the engines at their full thrust capability, which is about 7 or 8% - almost 10% - more than what they currently run at. Note that "full thrust" has been used to refer to increases in thrust twice, with different figures each time.

      Yes, an increase in thrust does have some impact on payload capacity, but it's not huge, and certainly a 10% increase in thrust isn't going to result in the 90% increase in capacity which you're suggesting.

      So, block 5 is about twice the power of the original Falcon 9.

      You just quoted the guy saying that it's "7 or 8% - almost 10%" more powerful, and now you're saying it's "twice as powerful". I think you're having a bit of a math fail.

    11. Re: a cost compare by Bruce+Perens · · Score: 1

      There have been several power increments since the original Falcon 9, so yes, it's about twice as powerful. It is also more powerful than the original specifications for FH, which is why there aren't more missions for FH.

      And I see that they are quoting the GTO missions in expendable and non-expendable mode, but they aren't quoting the LEO missions that way - and they used to. Also, they have learned a lot about landing the rocket and may be more confident now that they can do it on less fuel. So, until they actually quote block 5 missions differently, I'm going to assume that yes, there was a really big change between block 4 and 5, and they really are quoting that weight for a recovery mission.

      --
      Bruce Perens.
    12. Re: a cost compare by c6gunner · · Score: 1

      There have been several power increments since the original Falcon 9, so yes, it's about twice as powerful. It is also more powerful than the original specifications for FH, which is why there aren't more missions for FH.

      Now I know you're on crack. The FH is 3 F9 cores strapped together. I don't care what kind of "power increments" you're making, 1 core isn't going to be more powerful than 3. That would require a whole new engine design and a switch to a different kind of fuel entirely.

      Please find me any reference anywhere which suggests that the FH was originally specified to lift less than 23 tonnes to LEO. No, you can't cite your imagination.

      And I see that they are quoting the GTO missions in expendable and non-expendable mode, but they aren't quoting the LEO missions that way - and they used to.

      They're not quoting missions at all; they're quoting maximum capabilities of the rocket, and then giving a price per launch based on the less capable reusable mode. Why? Because they don't want to keep destroying rockets any more. With the block 4 they actually wanted to get rid of them. With block 5 they want to fly them reusable as much as possible. If you have a bunch of extra cash lying around you can still email them and ask for an expendable launch, but there's no reason for them to put the price on the page.

      Also, they have learned a lot about landing the rocket and may be more confident now that they can do it on less fuel.

      Even if that were true it doesn't help you much. The figures for reusable vs expendable lift capacity have always been 22 and 13. That means that they are keeping back, at most, 9 tonnes of fuel to make the landing. Even if they magically reduced that by 50%, it would still only result in 17 tonnes to LEO. And there is absolutely no way they cut it down that much; a more believable 10% fuel reduction would only increase the payload by 1 tonne or less.

      So, until they actually quote block 5 missions differently, I'm going to assume that yes, there was a really big change between block 4 and 5, and they really are quoting that weight for a recovery mission.

      Sure, why not. You've successfully demonstrated that the difference between a Block 4 and Block 5 is a less than 10% thrust increase, and you've linked to a page which shows that the standard reusable launch to GTO provides only 66% of the maximum payload capacity of the rocket. But you're going to assume that the numbers for LEO are double that of Block 4 because magic.

      Best of luck with that.

    13. Re: a cost compare by Bruce+Perens · · Score: 1

      Now I know you're on crack. The FH is 3 F9 cores strapped together. I don't care what kind of "power increments" you're making, 1 core isn't going to be more powerful than 3. That would require a whole new engine design and a switch to a different kind of fuel entirely.

      You're being a troll or you just don't know anything about this. The current Falcon 9 is more powerful than the original specifications of Falcon Heavy. This is because of improvements in the rocket and a stretch in its height. All of the missions previously scheduled for Falcon Heavy were transferred to Falcon 9 because of this. The two remaining missions for the Falcon 9 are for much heavier weights than SpaceX was able to book before the various increases in power of Falcon 9.

      And people tell me not to feed trolls, so that's all I'm saying.

      --
      Bruce Perens.
    14. Re: a cost compare by c6gunner · · Score: 1

      You're being a troll or you just don't know anything about this. The current Falcon 9 is more powerful than the original specifications of Falcon Heavy.

      No, me pointing out that you're just making shit up is not "trolling". You clearly have no clue what you're talking about. Either provide a reference for this insane claim, or fuck off.

      This is because of improvements in the rocket and a stretch in its height.

      Those improvements were all done back in 2011-2013, when they went from Version 1 to the Version 1.1. In the intervening upgrades from 1.1 to 1.2 (aka "full thrust) to Blocks 3, 4, and 5, there has been no change to it's "stretch". Meanwhile the first FH didn't fly until 2018.

      If the original design of the FH was based on the earliest 1.0 model of the F9, it still would have been able to lift more than a modern F9. The early F9 had a maximum payload to LEO of 10 tonnes. The current version has a max to LEO of 22.8 tonnes (expendable). The FH, based on the current variant, has a Max to LEO of 63.8 tonnes (expendable).

      Some quick math says that the FH based on the current F9 can lift about 2.8 times as much as a current F9. Applying that to the original F9 means that an FH based on the original F9 should have been able to lift 28 tonnes to LEO. This is still 5-6 tonnes more than the current F9 can do. So, again, if you're going to keep insisting that the current F9 can lift more than the original FH was designed to lift, you are going to have to provide some citation, or some math. Repeating yourself over and over again while linking to sources which contradict you doesn't really get you anywhere.

      All of the missions previously scheduled for Falcon Heavy were transferred to Falcon 9 because of this.

      Kind of. The actual reason they were transferred was because the FH wasn't ready yet. However, the fact that the F9 was upgraded to lift heavier loads meant that most of the missions which couldn't be flown on the original F9 could be flown on the V1.1 variants.

      The FH didn't fly at all until earlier this year. It does, however, have 3 missions lined up in the near future, so your insinuation that it's being phased out is just absurd. They will doubtless continue booking many more, though the FH will always be in less demand than the F9 since very few missions require that much payload capacity.

      And people tell me not to feed trolls, so that's all I'm saying.

      I wish more people would tell you to stop making shit up, instead. Then you wouldn't be in the insane position of trying to claim that SpaceX magically doubled their maximum launch capacity between Block 4 and Block 5.

    15. Re:a cost compare by Anonymous Coward · · Score: 0

      Probably because there isn't much of a market for payloads that large.

      so...Falcon Heavy makes for a good business plan how?

      Although, if you look at the no shortage of customers launch to GTO, Ariane5 obliterates the supposed superior Falcon9 by at factor of 2x once again.
      Average Falcon9 GTO payload is ~5 tonnes, while the average Ariane5 GTO payload is ~10 tonnes.

    16. Re:a cost compare by cheesybagel · · Score: 1

      The ECA variant is not "less capable" it is optimized for GEO satellites at higher orbits and has a LOX/LH2 powered upper stage. The ES variant is hypergolic powered so it's lower performance in terms of payload to higher orbits but it is capable of multiple restarts to insert satellites into multiple orbits. Had the ESC-B variant with the Vinci engine been introduced as supposed to that would have been LOX/LH2 with multiple restarts. i.e. high payload capable and capable of multiple orbit insertion. Interestingly one reason why it was cancelled, although the Vinci engine had already been developed, was because Soyuz was cheaper. Yet they had to end up using Ariane 5 in the end to launch Galileo anyway. I kinda of expected this to happen though.

    17. Re:a cost compare by K.+S.+Kyosuke · · Score: 1

      But Bruce, Ariane has lifted a number of 20 ton payloads to LEO. Spacex cliams to be cheaper, but nobody in the 20 ton class gives a shit about Falcon9?

      Since many real-world payloads are volume-limited rather than mass-limited, the 20 tonne capability of Falcon 9 is being seen as less relevant. For example, the 20-tonne ATV spacecraft would have never fit into Falcon 9's fairing. It was more than ten meters long at a 4.5 meter diameter but the F9 fairing stops being 4.5 meters wide internally before 8 meters of length. It fit nicely within the 40% larger Ariane 5 fairing.

      --
      Ezekiel 23:20
    18. Re:a cost compare by Anonymous Coward · · Score: 0

      Since many real-world payloads are volume-limited rather than mass-limited, the 20 tonne capability of Falcon 9 is being seen as bullshit.

      ftfy
      Are you seriously accusing Spacex "Lead Designer" (actual title he gave himself) Elon Musk of overlooking a undersized fairing that cannot accommodate many real-world payloads?

      Guess what Kyosuke, you need to apply for a upgrade in pay scale from mere boss cocksucker, because the fairing is exactly the same size on the upcoming Falcon Heavy, a serious problem which we, yeah we(you and me bro), inadvertently discovered!

      There's also the unfortunate fact from above where Ariane5 has a consistent 2x GTO launch payload advantage over Falcon9, which your fairing concerns do not apply.

    19. Re:a cost compare by K.+S.+Kyosuke · · Score: 1

      Nothing has been "overlooked", the fairing was designed for a launch vehicle of a certain class years ago before the capability of the launch vehicle significantly increased. That Ariane 5 has a "payload advantage" (more like 1.5x, actually) is apparently not that crucial since Ariane 6 allows to scale it down. Right now, Ariane 5 has operational problems with mating matching payloads.

      --
      Ezekiel 23:20
    20. Re: a cost compare by K.+S.+Kyosuke · · Score: 1

      Putting the two together, the rocket can lift 5.5 tonnes to GTO in reusable mode, and 8.3 tonnes in expendable. Extrapolating that down to LEO gives the same numbers I quoted earlier; 22 tonnes expendable, or 13 tonnes reusable.

      You're extrapolating wrongly then. In no way should you be getting a 1.5 ratio for GTO payloads but 1.7 for LEO payloads. Better outline your Tsiolkovsky calculations.

      --
      Ezekiel 23:20
    21. Re: a cost compare by K.+S.+Kyosuke · · Score: 1

      Some quick math says that the FH based on the current F9 can lift about 2.8 times as much as a current F9. Applying that to the original F9 means that an FH based on the original F9 should have been able to lift 28 tonnes to LEO.

      That is stupid quick math because the original Merlin engines are not throttleable. You can't just apply a multiplier like that if in one case, all the engines burn out at the same time and in the other case they don't. You have to do an entirely new performance calculation.

      --
      Ezekiel 23:20
    22. Re: a cost compare by c6gunner · · Score: 1

      I'm aware of that; I was keeping the math simple because it's a close enough approximation for my purposes, and it's still far better than anything that he has provided (that being nothing whatsoever).

  4. One came down, but not the other? by Anonymous Coward · · Score: 0

    SpaceX's Falcon 9 rocket, it launched from the West Cost

    I know the cost of living in California is high, but this is getting a bit out of hand. Also didn't know that "West Cost" was a proper noun.

    Now I do.

  5. More debris to space? by Anonymous Coward · · Score: 0

    What will they do with these obsolete satellites constellations?
    To convert to debris?

    1. Re:More debris to space? by bobbied · · Score: 4, Interesting

      Actually a very good question...

      LEO satellites are usually orbited low enough that they will naturally re-enter with in a few years of "unpowered" flight, such as after it's run out of fuel or is no longer controllable. So LEO orbits are generally self cleaning over time.

      For orbits that are higher, the natural decay times can be quite long (as in practically not going to happen) and in such cases the usual thing is to either plan to deorbit the satellite by putting it into a highly elliptical orbit where it drags in the atmosphere at the low point and letting gravity take it's course, OR you plan a parking orbit out of the way. Such things usually take fuel and active control of the satellite so they are not always successful. Also, some orbits have natural collection points due to the gravity between say the moon and earth. These points are often the final destination of space junk as it's a low energy way to get it out of the way into a place where it will naturally stay without help, which is a good thing.

      So for LEO the issue of debris is naturally correcting, though still a bit of a risk to the satellites that operate there because of the relative speed differences which can be very high for objects in different but crossing orbits. However for LEO, there are all sorts of possible orbits and directions so you can usually stay out of each other's way. Form geosynchronous orbits the relative speed differences is quite low, given that the whole point is to make the satellites all stay in one place in the sky. This stacks up a lot of hardware in a very small space though so collisions would be more slow motion train wrecks that won't create a lot of debris than quick obliteration events that generate a lot of fast moving objects.

      Of course there are all sorts of highly elliptical orbits used for various types of satellites and these are usually designed to be decaying over time, with their low points being at or near LEO levels. As in most of this stuff, they have a planned way to get the used up hardware out of the way somehow.

      So no, we certainly don't convert them to debris, usually, though some have been used for target practice to prove anti-satellite weapons actually can work. Such weapons have been demonstrated by multiple countries, including the USA, China and Russia/Soviet Union.

      --
      "File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
    2. Re:More debris to space? by skoskav · · Score: 1

      Low Earth orbit satellites such as Iridium (781 km above sea level) seem to be left to decay back to Earth within a few decades. Galileo satellites at 23222 km that are to be decommissioned boost themselves 300 km further into a graveyard orbit.

    3. Re:More debris to space? by skoskav · · Score: 2

      Form geosynchronous orbits the relative speed differences is quite low, given that the whole point is to make the satellites all stay in one place in the sky. This stacks up a lot of hardware in a very small space though so collisions would be more slow motion train wrecks that won't create a lot of debris than quick obliteration events that generate a lot of fast moving objects.

      Only until an evil scientist sends a box of nails going in the opposite direction.

    4. Re:More debris to space? by Anonymous Coward · · Score: 0

      "... letting gravity take it's course"

      its

    5. Re:More debris to space? by Anonymous Coward · · Score: 0

      It sort of has happened before, the USA did a nuclear detonation in the atmosphere that fried the electronics of a few early satellites that where used for communications. They decided not to do that again.

    6. Re:More debris to space? by Bruce+Perens · · Score: 1

      A de-orbit plan is a required part of the licensing process. Even for cubesats these days.

      --
      Bruce Perens.
  6. polar versus geostat orbit by goombah99 · · Score: 1

    Hmmm.... don't know enough orbital mechanics to argue but getting heavier sattelites 8 times further away seems like it might take a much larger rocket than the space-X one. So is there much to compare here?

    --
    Some drink at the fountain of knowledge. Others just gargle.
    1. Re:polar versus geostat orbit by AHuxley · · Score: 1

      Re "So is there much to compare here?"

      The USA had done really great work with the DC-X https://en.wikipedia.org/wiki/...
      The Soviet union was considering Zarya https://en.wikipedia.org/wiki/...

      --
      Domestic spying is now "Benign Information Gathering"
    2. Re:polar versus geostat orbit by quenda · · Score: 4, Interesting

      Hmmm.... don't know enough orbital mechanics to argue but getting heavier sattelites 8 times further away seems like it might take a much larger rocket than the space-X one. So is there much to compare here?

      The two rockets are very comparable. In expendable mode, the Falcon-9 has a greater payload capacity (to the same orbit) than the Ariane 5, 8.3 tons vs 7, but with reuse it is less, only 5.5 tons to GTO.

      In rocketry, is is not about power, distance or energy, rather it is thrust and delta-V (change in velocity). Higher orbit means higher velocity.
      You need around 10km/s to get to low-orbit, and another 2-3 for the higher Galileo orbit, similar to geosync transfer orbit. So the "8 times further" is misleading.

    3. Re:polar versus geostat orbit by K.+S.+Kyosuke · · Score: 1

      Ariane 5 has definitely more than 7 tonnes to GTO capability (for a lot more money than either of the F9 flight options, though).

      --
      Ezekiel 23:20
    4. Re: polar versus geostat orbit by c6gunner · · Score: 1

      Correct; the current model of the Ariane 5 can lift around 11 tonnes.

      I wasn't sure about the cost, so I looked around. Holy crap. A launch on the Ariane 5 costs more than one on the Falcon Heavy, and the FH can lift more than twice as much.

    5. Re: polar versus geostat orbit by quenda · · Score: 1

      Thanks folks, I was quoting figures for the old model Ariane 5 from ten years ago.

      It looks like the Falcon heavy can do 16 tons to GTO while recovering the side-boosters.
      Recovering the core booster drops that to only 8 tonnes, similar to an expendable Falcon 9.

      Note that SpaceX is quoting prices for fully reusable, but capacities for fully expendable.
      So the $90m lowest price tag for FH comes with a lower capacity than the current Ariane 5. (but half the price)

    6. Re: polar versus geostat orbit by cheesybagel · · Score: 1

      Ariane 4 used to have low launch costs. But most customers who use the Ariane 5 right now do it mostly because of the high reliability of the rocket vs large Russian rockets like the Proton. Of course SpaceX has been snatching away that market from all the other operators.

  7. Someone's been reading by sphealey · · Score: 1

    - - - - - The atmosphere offshore, where the Just Read the Instructions droneship was stationed 235km away - - - - - -

    Someone's been reading their Iain M. Banks. But I'd still like to see the cost/benefit analysis from a Ship Mind on adding the additional fuel/oxidizer, control surfaces, and other equipment + inspections and refurbishment costs to allow stage recovery. Intuitively it doesn't seem to make sense, but perhaps a great Mind existing partially in hyperspace sees what mere humans cannot.

    1. Re:Someone's been reading by Anonymous Coward · · Score: 0

      Iain Banks got the translation wrong. He thought they meant mighty intelligent space ships, but actually they were repurposed barges used in spacecraft recovery at sea. Easy mistake to make though.

    2. Re:Someone's been reading by Anonymous Coward · · Score: 0

      Space X has some great people doing the PR work and letting the geeky engineering things like the barge names out to the public. It makes it fun to follow the reports.

    3. Re:Someone's been reading by Namarrgon · · Score: 2

      The extra fuel is dirt cheap compared to the cost of the booster. Estimates vary for the cost of a booster core, maybe $20-30M, but the price of that will come down anyway now that they're finalising their F9 design with Block 5. Musk has said that the cost of refurbishing Block 4 for reflight was less than half the new cost, so still definitely worth it - and Block 5 is designed to fly with minimal refurb (as little as 24 hour turnaround) so will certainly cost a lot less than that to refly. And the added capital cost of development, reuse systems like control surfaces, and recovery ships is amortised out over dozens of launches so should be minor in the long run.

      --
      Why would anyone engrave "Elbereth"?
    4. Re:Someone's been reading by sphealey · · Score: 2

      the cost of carrying extra fuel isn't the purchase price of the material - which is usually low compared to the per kg cost of the rest of the vehicle - but the opportunity cost of the extra weight carried, the extra structure needed to carry that weight, the large control surfaces needed to manage the higher weight, and so on all the way down to the last turtle.

    5. Re:Someone's been reading by Anonymous Coward · · Score: 0

      You're mixing in your Banks with your Asimov.

    6. Re:Someone's been reading by Ksevio · · Score: 1

      Probably their biggest benefit is not needing to manufacture all the new rocket parts. There are plenty of customers so the more rockets they launch, the more money they make, and if they can refurb old ones faster than build them from scratch, that's going to mean more money coming in.

    7. Re: Someone's been reading by c6gunner · · Score: 1

      The amount of extra fuel needed is relatively low but, regardless, all of that is included in the launch price. If you want to put 13 tonnes or less into LEO, it will cost you about $60 million, which is comparable or less than every other launch option. The cost of the extra fuel needed is included in that price, and results in a lower payload capacity.
      If you want to use the rocket to it's full potential and put 22 tonnes into LEO, it will cost you significantly more than $60 million so that SpaceX can build a new rocket to replace the one they junked at your request.

    8. Re:Someone's been reading by Namarrgon · · Score: 1

      You're not wrong, but in practice this is rarely an issue. Have a look at the payload masses on SpaceX's mission list - the great majority of payloads didn't come close to their maximum capacity, meaning the mass overhead of recoverability is a non-issue most of the time.

      While it's true they give up a tiny percentage of customers who need slightly more than their reusable rocket can now deliver, it's more than made up for by the savings of of reuse. They've also expended a handful of boosters that didn't have enough capacity to loft their heavier payloads and still make it back, and these boosters flew without many of the recovery control surfaces like the grid fins, so their design is flexible enough to support both approaches.

      --
      Why would anyone engrave "Elbereth"?
  8. Catching the fairing is fun and all... by Jeremi · · Score: 1

    But wouldn't it be more reliable to design a fairing that floats and can tolerate a few minutes/hours of contact with seawater?

    Then instead of having to catch it in the air, the boat could just go to where it touched down and collect it.

    --


    I don't care if it's 90,000 hectares. That lake was not my doing.
    1. Re:Catching the fairing is fun and all... by HornWumpus · · Score: 1

      The do float, but they get water logged.

      I'd take it, water logged and all, make it into a shed.

      Argh, who's got a fast, ocean going, boat? We're going to pirate one of the next two off CA. Your boat, you get the first.

      We'll stalk the recovery ship, they know about where they're coming down. We go for the one they don't go after, gone before they know what happened.

      --
      John McAfee 'It was like that time I hired that Bangkok prostitute; to do my taxes, while I fucked my accountant'
    2. Re:Catching the fairing is fun and all... by Bruce+Perens · · Score: 2

      It definitely floats. It is really light and rides astonishingly high in the water for something its size. It just gets damaged.

      A fairing is 5 Million dollars of mainly carbon composite. If it's a pound heavier, that's a pound you can't have for payload. This gets really important with geosynchronous transfer orbit or (worst) direct geosynchronous, where the capability is much lower than LEO. Adding weight means there will be some missions you can't carry. I guess they could have heavier fairings for when they can afford the weight, but SpaceX likes to have only one assembly line for something if at all possible. There is a complexity cost.

      While the ship can be as heavy as you want.

      In the end, the net recovery just might not work. We'll see.

      --
      Bruce Perens.
    3. Re:Catching the fairing is fun and all... by K.+S.+Kyosuke · · Score: 1

      If it's a pound heavier, that's a pound you can't have for payload.

      Not really, if they're discarded nowhere near orbital velocity. (However, if it's too heavy, it's impractical to land by means of parachute, etc. etc.) There's some loss but nowhere near 1:1.

      --
      Ezekiel 23:20
    4. Re:Catching the fairing is fun and all... by Bruce+Perens · · Score: 1

      Good point. It's less than 1:1 fairing weight to payload weight loss. The fairing is dropped pretty close to the time that stage 1 ends its burn, and most of the delta-V is in stage 1. So, let's say 1:0.8

      --
      Bruce Perens.
    5. Re:Catching the fairing is fun and all... by Bruce+Perens · · Score: 1

      There is an international treaty that says SpaceX still owns the rocket, it's not like an abandoned ship. Or yeah, I'd be tempted to get in the space souvenir business.

      --
      Bruce Perens.
    6. Re:Catching the fairing is fun and all... by K.+S.+Kyosuke · · Score: 1

      The fairing is dropped pretty close to the time that stage 1 ends its burn, and most of the delta-V is in stage 1

      It's around 2 km/s for Falcon 9 with landing the first stage, with a total delta-v of around 10 km/s for GTO missions. So I'd say that most delta v is in the second stage, unless you were trying to say something else than I thought you were trying to say. The F9 throws away the fairing shortly after igniting the stage 2 engine (after expending around 15 tonnes of propellant in the latest flight), at the point when the total mass of the remaining stack is still around ~100 tonnes, so I'd be very surprised if the effect were any higher than, say, 0.3 kg of payload for 1 kg of fairing mass delta. And that can be overshooting a lot still, I'd have to make a more accurate calculation of my own, but the calculator at http://www.silverbirdastronautics.com/LVperform.html gives me quickly a figure of around 0.1 kg of payload mass lost per 1 kg of fairing mass increased (for a GTO profile), which sounds intuitively about right to me.

      --
      Ezekiel 23:20
  9. and that, in a nutshell, is why... by Anonymous Coward · · Score: 0

    one of these companies will be around for a long time and has a very bright future that may well include Mars, while the other one will bump along surviving on massive subsidies.

    Both are able to put a payload into orbit. One is truly innovating and has the optimism and confidence to be working on realistic plans for a grand future, the other is selecting technologies and allocating work among member nations along political lines as a high-tech jobs program.

    1. Re:and that, in a nutshell, is why... by Anonymous Coward · · Score: 0

      > Both are able to put a payload into orbit. One is truly innovating and has the optimism and confidence

      It's not that simple. Arianespace has extreme reliability in its track record, once they had a row of 40+ (more than 40!) successful launches with the Ariane-4 rocket. If your payload is extremely expensive or secretive and took several years to build, booster reliability could trump launch costs.

    2. Re:and that, in a nutshell, is why... by Anonymous Coward · · Score: 0

      "If your payload is extremely expensive or secretive and took several years to build, booster reliability could trump launch costs."

      Yep, there's a reason why NASA is using Soyoz rockets for crewed launches.

    3. Re: and that, in a nutshell, is why... by c6gunner · · Score: 2

      This is largely meaningless. Most rocket failures happen in the early stages of a program, while the bugs are being worked out. And the Ariane 4 was a derivative of earlier rockets in the same family. So, all in all, being able to have a streak of 40 success isn't at all unexpected.

      The overall success rate for the Ariane 4 has been 97.4%. The Soyuz-U has a very similar 97.3% success rate, while the Falcon 9 has a success rate of 96.6% thusfar. Now, the Falcon 9 has not have had enough launches for that rate to be particularly meaningful; it's quite possible that, after 500 launches, it will be significantly different. However, given that the majority of failures tend to occur early on, it seems likely that their rate will only get better in the future.

      Either way, the reliability of the Ariane compared to the Falcon is not a significant factor at this point given that there's less than a 1% difference between them.

    4. Re: and that, in a nutshell, is why... by c6gunner · · Score: 1

      Yep, there's a reason why NASA is using Soyoz rockets for crewed launches.

      Yep, that reason being "because they have no other option".

  10. One can say USA USA USA by Anonymous Coward · · Score: 0

    The other can say

    well, whatever the Frenchies say about their prison in French Guiana. If only Steve McQueen and Dustin Hoffman were still alive they could tell the French what they think.