68 thoughts on “The Dragon Approaches”

    1. Here’s what I saw:

      * Original “hold” position was 200m but NASA got cold feet and changed it to 235m.

      * As a result the thermal cameras didn’t work as designed.

      * After 25 minutes of what can only be described as “finger pointing”, NASA gave go-ahead for a hold at 200m, as originally planned.

      * Shortly after there was a stray retroreflector return from the JEM which screwed up the LIDAR.

      * SpaceX fixed the problem in short order, but NASA decided they needed 30 minutes to talk it over.

      * NASA started talking about the desperate need to capture the Dragon in daylight.. this would add 98 minutes to the timeline.

      * Dragon approached to 10m and it was obvious that shadow of the ISS was going to shroud the Dragon in darkness regardless of the Sun (this was obvious to everyone at 30m)

      * NASA announced the 98 minute delay was still necessary, despite turning on the flood lights on the ISS to remove the shadow.

      * Silence for 20 minutes.. obviously some arguments going on between SpaceX and NASA.

      * All of a sudden the 98 minute delay and the need to dock in sunlight is gone.. The robotics team is given the go-ahead to capture.

      * Capture happens and there’s lots of high fives, followed by the SpaceX team immediately changing shifts.. they wanted to go home.

      * Reluctantly the NASA side also changed shifts.

      * Three hours later the Dragon is moved the 10m to the “first capture” of the berthing.

      All in all a success, but none of those delays were prudent.. they were just annoying.. I felt like I was watching the line move at the DMV.

      1. Here’s an interesting quote that is in some ways related…

        …despite a science payload exquisitely adapted to the tasks it was designed for, surely we failed to recognize and understand important clues to the geologic history we came to investigate. The experience of exploring a planet with a rover is both incredibly exciting and rewarding and incredibly frustrating. It is science by committee modulated by engineering constraints. … a human geologist could have performed the years of exploration done by Spirit in just a few weeks or perhaps days.

  2. Capture. Somebody probably needs to re-sharpen their pencil with all the C3 check-marks happening.

  3. They’re getting close to berthing now.

    I don’t know why these things happen so slowly. If I did, I’d be a rocket scientist or sumpin’.

    1. Like everything else, I’m positive the time flies when you’re actually the one doing the job.

      Also, no brakes in space.

    3. Rickl,

      There’s several things, but Newton’s laws explain the majority of the problem. Particularly the third law about every action having equal and opposite reaction. As the SSRMS (ISS arm) moves the Dragon closer to docking, it actually is creating a moment force down the ISS that torques the station. When you do this on the ground, the friction of your feet on the ground takes care of the opposite reaction. For ISS, that moment force is countered (preferably) by the control moment gyros (gyrostabilization). There’s only so much the CMG’s can counter before they become saturated, about 14,000 ft-lb/sec. Once the CMG’s are saturated, the ISS will begin to tumble… well maybe not. Actually, the CMG’s are relaxed by firing reaction control system (RCS) thrusters on the Russian part of the ISS. When the RCS are saturated, then ISS tumbles.

      While Dragon is not likely to cause ISS to tumble, something very large, say a docking Space Shuttle, could. However, while mass is part of the equation, note the units for CMG capability: ft-lb/sec. The distance the object is from the center of mass of ISS is an issue. And then there is the time, how quickly you change the position of the mass (again with Newton’s laws). It takes a force to move the position of Dragon’s mass and that force is a product of the mass times the acceleration (distance over time squared). Finally, the CMG’s are not always completely desaturated (all 14,000 ft-lb/sec to play with). Sometimes they are carrying torque from a previous activity.

      As for the other “several things”, when you get closer to docking, you may have to deal with static charge build up. During the entire operation, you want to make sure Dragon is getting enough sunlight on its solar arrays to stay sufficiently powered. And after docking, opening hatch takes time while they fill the vacuum between the hatches and conduct leak tests.

      1. The whole “Use the Canadarm” plan screams “Why didn’t we think of that earlier?!?” to me. Forty years of science fact and science fiction without a small, “nimble” intermediary doing the final finicky bit.

      2. Thanks, Leland, for the detailed explanation. Thanks, Titus and Bob-1, too.

        I knew it basically had to do with the fact that, in zero-g and a vacuum, an object that starts to move in the wrong direction will tend to keep moving until it hits something, and it’s hard to stop it. But that was pretty much the extent of my knowledge.

  4. Dragon is berthed! This is momentous! Watching this is much more stimulating than caffeine!
    I’ll try to curb my enthusiasm..

  6. Successful rendezvous, capture and berthing. Kudos to SpaceX and NASA. This could well be the dawn of the true Space Age.

    The real test will come, of course, when SpaceX loses a vehicle with crew. God forbid, of course, but statistically it’s inevitable. If the loss comes early, the Axis of Cynicism will pounce upon and devour commercial space travel. If it comes after a reasonable period of trouble-free operation, it may be looked upon as just another transportation disaster story — and those of us who are still more or less young have got a shot at someday going into space for the price of a ticket.

    Up next: the Lindbergh/LeCroix Moment. If “D.D. Harriman” can put a man on the moon on his own dime, it’s Spirit of St. Louis — or, more appropriately, Spirit of Saint Joseph of Capistrano — time.

    Thanks to Mr. Musk and the gang for officially making my day.

    1. Poorly worded, but being kind to the journalist (after all, they aren’t that smart to begin with) it’s really two statements: A collision could prove disastrous; orbital speed 17,500 mph. The implication of conflation just doesn’t register.

    2. I don’t know what the relative speed was when a Progress resupply craft collided with Mir, but the damage was pretty extensive. Yeah, the orbital velocity has nothing to do with it, just the relative velocity, but collisions aren’t a good thing.

  9. Short ‘from memory’ of the issues notices by SpaceX:

    1) They had a delay at around 250m because the thermal imagers were having difficulty “with the Sun”, which I assume is just a timing issue with the Sun passing behind (or close enough) ISS relative to Dragon.

    2) Second issue was with the 2 LIDARs on approach. When the targeter veered off of the well-understood target area, they would get “odd readings”. This was portrayed as an incomplete understanding of the ISS-geometry/reflectance outside of the actual target area. So they weren’t getting both LIDARs to converge on a positioning answer. So they manuvered some, reset the ‘no answer’ LIDAR a couple of times, and eventually continued with two convergent LIDAR. Only one was “needed”, but they had two at each advancement point until parked at the capture point.

    1. Over at space.com they are saying the LIDAR was being confused by the shiny exterior of the Japanese laboratory. The adjusted the aperture of the LIDAR sensor to narrow the field of view down around the target area.

  10. I refuse to believe the Dragon is attached to the ISS, since that’s clearly just more berther nonsense.

  11. Awesome, just awesome!!!!

    Rand, thank you for speaking truth to power the other day (you reprsent so many of us who have no such opportunity), and I think today’s events put an exclamation mark on it. 🙂

    Dragon is at ISS! I hope this leads, in the not too distant future, to a manned Dragon doing the same. I’d also really like to see SpaceX start flying its commercial Falcon9 manifest. Right now, my main worry is their launch rate. Can they scale up like they think?

    One note of caution; the mission isn’t over. It’s been a success so far, and arguably the hard part is over, but it’s not yet time to uncross the fingers.

  13. Congratulations! Now all that is left is the unberthing and recovery. But great going so far!

      1. Ken,

        I just wonder how many Dragonlab flights he could have made in the last two years:-)

        1. Reading Trent’s response to Ed above I couldn’t help but think how we need a new branch of humanity on mars ASAP. If some were to choose a mars settlement charter and just start making reasonable claims all the better. We’ve become too civilized, believing other people have a right to control our lives.

          Now more than ever people need to assert their independence while there’s still a chance. God how I hate the control freaks that disrespect other peoples rights and want to control so many details of their lives. Might does not make right. Right only exists when people start to stand up for it.

          1. Ken,

            SpaceX needs to break free of NASA before that happens. Otherwise the first folks they will take there will be NASA astronauts, and NASA will use “scientific research” as an excuse to put it off limits to civilians. After all, you don’t want granny waiting on Mars for the NASA astronauts with a fresh apple pie 🙂

          2. Think about it and you will realize they are free. So they provide cargo flights. This does not require their capacity. Later they provide crew… still not taking up their capacity. 1800+ can build a lot of rockets (they do need more launch site and are in the process of acquiring them.) What more can NASA take? Red Dragon just helps them get experience landing on mars… it doesn’t take up their capacity either.

            It’s good to warn of potential danger. But you have to look at the whole picture. NASA will never control SpaceX more than just around the edges. While at the same time, SpaceX does get the benefit of some of their best people.

          4. Ken,

            [[[But you have to look at the whole picture. NASA will never control SpaceX more than just around the edges.]]]

            That sounds more like wishful thinking, especially given the track record of Telsa and Solar City. Yes, in theory Elon may be able to tell NASA no, but the same theory applies to Boeing and Lockheed. And the more workers you have to support the more difficult it will be to say no.

            I am hopeful with the new SpaceX agreement with Bigelow Aerospace, but if SpaceX’s track record on COTS is an indication they will likely be focused on CCDev\CCP and put Bigelow Aerospace on that back burner, like they did with Dragonlab and COTS.

            As for other launch sites, yes SpaceX does need them, but they don’t seem to be looking in the right places, especially in regards to their reusable first stage.

          5. …especially in regards to their reusable first stage

            I suspect I have some idea but what do you mean?

            —————

            He’s already said he would say no under some circumstance and the govt. seems to have backed down on their threat. Now that a successful mission has gone to the ISS, Bigelow sees the potential to support his business plan. Especially since the Dragon could be providing passenger service to his modules as is. SuperDracos are more for the Red Dragon and may never be used as a LAS. Cool the way he got the govt. to pay the development costs, eh? He hopes to get the govt. to pay for testing it as a mars lander as well. That doesn’t put NASA in charge either. It just makes good sense. Tesla and Solar City don’t really interest me much.

            BTW, I’m putting together an evergreen Steps to Mars page which is quite preliminary right now, but would appreciate your critique (criticism or what have you.) I intend to flesh it out with as much detail as I can. Eventually becoming a complete detailed plan for a mission.

          6. Ken,

            The original research that was done for Spaceport America, when it was the Southwest Regional Space, was as a launch site for SSTO and TSTO RLVs. There were corridors mapped out for polar, ISS and easterly orbits that provide good secure sites for a reusable booster to land at. Its an ideal site for both flight testing the Grasshopper and for operational flights.

            There were another good site in Nevada. The southeast coast of the Big Island of Hawaii also has a number of good sites.

            I do hope Elon is able to avoid being stuck to the NASA Tar Baby. But I have seen other firms, like Orbital Sciences, follow the same path. And if SpaceX goes IPO Elon will have stockholders to answer to as well even if he keeps a majority of the shares.

            Yes, I will look at it. Post the link when its ready.

  14. Before the flight of the first F9, I mentioned somewhere that the third flight was the one that worried me. Sometimes it is really good to be wrong. It kept occurring to me that some people with the same fears have been spreading FUD.

  15. Where is that “Joe” dude that was all mouthy after the launch abort Saturday morning??

    1. *waves hand* He’s not the troll you are looking for.

      He has been told several times to leave, if he can’t be bothered to take some effort to understand what’s going on. Maybe he took our advice.

  16. Has anyone heard if Spacex is going to ‘name’ each Dragon capsule?

    I vote ‘Serenity’.

    2. They’re planning on building quite a few Dragons so coming up with good names could be problematic.

      On a related note, back in the late 1980s, I was a satellite controller at what is now Schriever AFB (it was then Falcon AFS, AKA “Falcatraz”) working on DSCS-III comsats. The control center next to ours controlled GPS satellites. When they started launching the new Block II (the first operational GPS satellites as opposed to the R&D Block I birds), they started naming them after dead rock stars. IIRC, the first was named “Elvis” and the second was named “Janis”. While in an elevator one day, I asked a friend who worked GPS which dead drug addict were they naming the next satellite after. A bird colonel in the elevator looked rather unpleased. Very shortly afterwards, it was announced that they were no longer naming the satellites after dead rock stars or anyone else. Coincidence? I think not!

      1. Yep. Those 1800+ employees aren’t part of a congressional jobs program. They’re there for production. It’s almost as if SpaceX was a private business or sumptin.

    3. I wonder if SpaceX will send this Dragon to the Smithsonian after they recover it. Seems given the press on the flight it belongs there.

  17. I sent Elon a congratulatory e-mail today, subject: Happy Berth Day!

    Hope it becomes a tradition!

  18. Idea for new SpaceX t-shirt: “SpaceX Berther”, with “berther” in the same typestyle as the SpaceX logo.

  19. Good stuff! The reentry portion was already demoed so hopefully that part will also go along well. They probably have a lot of fine tuning to do for the next trip to the ISS (there’s always things you only catch when you actually do it). Yet the fact remains they managed to navigate to the ISS and properly berth to it. Plus it looked pretty smooth.

    This was a major milestone! The folks at SpaceX are probably already looking towards crewed flights as the next major hurdle. The rest is just fiddling about with the current setup.

  20. There was some discussion on the morning press conference (5/25) about the work schedule and personnel detailed to unload and reload the Dragon before its planned departure on 5/31. Only the names of the Americans and the Dutchman came up. The three Russkies aboard are evidently not being allowed to touch the Dragon. I know there was some argy-bargy a few months ago from the Russian space agency about possibly vetoing SpaceX’s whole mission for “safety” reasons. Perhaps there is a – possibly justified – fear of sabotage by one of our esteemed Russian friends? Will the No Russians Allowed policy be SOP for all future Dragon visits? The world wonders.

    2. Malarkey. NASA astronaut Don Pettit and Russian station commander Oleg Kononenko were the first to enter the Dragon after berthing. There’s a photo of them in Dragon giving side-by-side thumbs-ups.

      1. Yeah, I saw all of that too. I was just struck, yesterday, by the fact that no Russian names figured in any of the discussion then about upcoming activity.

        It’s certainly good that all hands can be on this particular deck. Granted, the ISS is a zero-G environment, but pulling half a ton of assorted freight out and then stuffing three-quarters of a ton of equally miscellaneous mass back in, entirely by hand, has got to be a bit of a job. When Dragon starts regular revenue freight runs with up to six tons at a time incoming, the barge-toting and bale-lifting will really kick into high gear. I guess the crews must be used to it, though. It would appear that pulling goods out of a Dragon should be much more straightforward than getting an equal mass of comparable packages snaked out of a Shuttle and into the ISS. Perhaps the longshoreman’s and warehousemen’s union will see fit to make ISS crews honorary members.

        1. Dick,

          Depends on how its packaged. When I was in the used book business with my brother I would load a 1/2 ton pickup by myself, basically 25 40-45 lb boxes full of books, in about a half hour, and I had to pace myself due to my asthma. Six strong astronauts should be able to empty it quickly, even if it had the full 6 tons.

          1. The habitation and working spaces of the ISS have a lot of right-angle bends. It seems as though the quickest way to empty a visiting resupply vehicle would be to put one crewman in the vehicle, station the others at key intersections, then do a Tinker-to-Evers-to-Chance thing with the packages. Probably the most fun way to get the job done too. Also probably thoroughly against the rules.

          2. Dick,

            I don’t know why it would be against the rules as such chains worked well in ships.

    3. I’m watching the press conference, and Don just said that all six of them have been briefly inside Dragon, but they haven’t taken any pictures. I hope they do before Dragon leaves.

  21. Would this be considered a ‘stable’ orbit? Or would it need to be regularized?

    “target orbit with a low point of 310 kilometers (192 miles), a high point of 340 kilometers (211 miles), and an inclination of 51.6 degrees.”

      1. That was kind of my thinking too, but it’s on the edge of that area. And I’m wondering if 6000 kg of propellant would be enough to make it ‘far enough’.

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