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Live: SpaceX Dragon docking with ISS (bbc.co.uk)
214 points by kingofspain on May 25, 2012 | hide | past | web | favorite | 98 comments

This is just awesome.

I'm sitting in the middle of the French country side in a building that was built during Galileo's life time with these links up across three monitors:




Watching all of this makes me realise just how lucky we are to be alive at this point in human history.

Oh and looks like first capture attempt could be as soon as 20ish minutes from now (i.e. 14:02 UTC).

Edit: they've just given a go for capture.

Edit 2: and here's a screen shot of the Dragon capsule and space station arm: http://imgur.com/OWit7

Watching all of this makes me realise just how lucky we are to be alive at this point in human history.

Indeed. Sexy times!

Captured dragon: http://imgur.com/Vmnzj and http://imgur.com/mQU91

NASA is broadcasting:


Anyone know what time it's expected to dock at?

spaceX says "coverage begins at 4:30 PT" http://www.spacex.com/

Here is that in your local time: http://www.wolframalpha.com/input/?i=4%3A30am+pt+in+local+ti...

It's in 1 hour 48 minutes from the timestamp of this comment

"Webcast start time now targeting 5:45 AM PT / 8:45 AM ET. Times are subject to change so please check back for updates."


current estimate: 9:40 AM CT (in the video stream, and they stress it's an estimate).

They just announced an 8:10 am central time for robotic capture. After the arm makes the capture it's about 3 hours until it is fully docked to the station.

Docking in orbit is harder than it appears. Speed and altitude are linked so you can't just thrust towards the station or you will wind up in a different orbit:


Dragon doesn't autonomously dock. It flies within range of the space station's robotic arm, is grappled, and then is slowly berthed to a docking port.

4:12AM CT according to the NASA broadcast

Which is 09:12 UTC.

Wow, it's 4:07ct and I just woke up (insomnia)...great timing. All I see is a small blinking light though.

When will it happen? Is it behind schedule or is the 4:12 CT time wrong???

Perfect, I haven't missed it yet!

anyone got a Youtube Live stream link? UStream is very slow here.

http://www.nasa.gov/multimedia/nasatv/index.html?param=stati... works for me, even though the ustream one did not.

It also appears that the docking isn't really supposed to start for another 2 hours.

Thanks for the update - where'd you get that snippet of information? I tried to find a schedule of sorts but had no luck...

According to the image that's currently on https://spacex.com/ , coverage begins at 4:30am PT.

Someone here submitted this last night as the low-def nasa-tv link. http://www.ustream.tv/channel/nasa-mobile

This is the only one which gives me actual video (though it's just of a computer screen atm, a deathstar-like graphic) - the others had voices, and no video but a small blinking light and vertical bands near the bottom of the screen).

uh oh, now it's also showing a blinking light and bands...

EDIT at last, Dragon sliding across the earth, from the ISS. Amazing seeing one spacecraft from another. Later, a thermal image of ISS from Dragon. But they're mostly showing people in front of computers...

Watching dragon sliding over those clouds is pretty hypnotic. You can see why they say watching earth from space makes the boundaries between countries disappear.

That's the same feed. That graphic was the exclusion zone around the ISS, now we're back to the blinking light.

You'll see the Earth behind in a few minutes when the ISS crosses back into day: http://www.isstracker.com/ http://www.timeanddate.com/worldclock/sunearth.html

What are the tiny objects that seemed to be criss-crossing all over the background of the blinking light (visible clearly in fullscreen) ? Other satellites?

either a city or another satellite. The first "mysterious light" I saw, which I thought was another lit satellite, was eventually described by the channel narrator as the city of Los Angeles going by far below. It was late at night, and we were seeing the lights from the LA metro area.

The NASA guy is using Windows XP, its pretty funny, he just screen-shared in the stream.

I'm sure its some super custom software though.

If NASA had switched to Vista, station would have deorbited.

I've been waiting for this for a long time. I spent the past two summers working on the Dragon docking as an intern.

Tell us more! Blog link about it?

Well I spent the last two summers as an intern at SpaceX working on several things, but one was that mechanism that the Canadian arm attaches to. I can't talk much about the specifics, but one of things I did was program the micro-controllers that interface with the motors that open the hatch door (and some other stuff) that contains the hook for the robotic arm to grab. I wish I could write more and even make a blog post, but I'm simply not allowed to do so.

Are you a programmer? Is the docing full automatic? Until know the only automatic thing was the ATV right?

I'm an electrical engineering student. When it came to docking mechanism I was an embedded systems programmer. Yes, to my knowledge the docking is fully automatic.

One of the monitor feeds: mms://a1709.l1856953708.c18569.g.lm.akamaistream.net/D/1709/18569/v0001/reflector:53708

(opens at least with VLC)

Where did you find a link to this?

meefs mentioned it on #startups IRC freenode

From https://spacex.com/updates.php

"FRIDAY MORNING - Final Approach, Dragon Grapple

Around 2:00 AM Pacific/5:00 AM Eastern NASA will decide if Dragon is GO to move into the approach ellipsoid 1.4 kilometers around the space station. If Dragon is GO, after approximately one hour Dragon will move to a location 250 meters directly below the station. Dragon will then perform a series of maneuvers to show systems are operating as expected. If NASA is satisfied with the results of these many tests, Dragon will be allowed to perform the final approach to the space station.

Sometime around 6:00 AM Pacific/9:00 AM Eastern, astronauts on the space station will grapple Dragon with the space station’s robotic arm and the spacecraft will attach to the station."

"We've got a dragon by the tail..."

"This sim went really well, let's do this for real."

Excellent to see astronauts with a refined sense of humor as well.

Is NASA doing the Ender's Game thing with their astronauts?

I see your static image and raise you a gif! http://dl.dropbox.com/u/123449/dragon/Dragon%20docking%20wit...

That's the sort of picture that makes me feel a tad patriotic (I'm Canadian).

The monitor view that they're occasionally showing displays a reticle over Dragon. Or it's supposed to, but the reticle is a bit off (Kuipers spent some time talking to houston about it).

It reminds me of the adventures that Pettit had with camera calibration yesterday, I wonder if there's a connection?

Anyway, listening to Pettit talk through the camera calibration yesterday made me think that there's a lot of room for improved UX in the software they use.

As an aside, I strongly dislike the term UX/User eXperience, it makes no sense to me. I could substitute 'UX' for 'design' above and all would be well in my world.

I might say that the operators of the 3 Mile Island nuclear reactor where having a fine "user experience" because the interface was telling them everything was OK...

User experience is the overall feeling you get from a well combined language, graphic design, sound, motion, information design, interface design, interface design, interaction design and programming.

That is the "industry accepted" meaning of the term, http://uxdesign.com/assets/ux-defined/user-experience-design...

Question: if Dragon is about 200m lower than ISS, and they are moving at the same velocity at one instant, wouldn't that put them in different orbits?

Assuming ISS's orbit was perfectly circular, then Dragon would be moving too slow for its lower orbit, and would sink down, to its perihelion when on the opposite side of the earth, and so on, oscillating up and down, in an elliptical orbit with respect to ISS.

The only solution I see is for Dragon to artificially make its elliptical orbit circular by continuously thrusting upward. But I don't see this in the video stream. Have I got this all wrong?

EDIT s/too fast/too slow/ # and related edits, thanks mmaunder

I don't think 200m is enough to put them in significantly different orbits. Every once in awhile, dragon probably fires a thruster to make small adjustments.

edit, clarification: The problem is that the object closer to the earth will experience more gravitational force, which needs to be counteracted by orbiting faster, so that it's constantly falling 'tangent' to the earth. If they had the same angular velocity and the ISS was known to have a static distance from earth, Dragon would be slowly falling towards the earth because in order to maintain a static distance from earth, things above the ISS need to travel slower while things below need to travel faster.

ISS video of the Dragon is from above, so upward thruster firing wouldn't be visible (that thruster would be on the other side of the vehicle).

At some point when they were a few meters away, the NASA video mentioned the Dragon was now "free floating". So, I think they were continuously gently firing the thrusters to maintain orbit until they got extremely close.

Aren't lower orbits faster? So wouldn't dragon be moving too slowly to maintain it's orbit, not too fast?

Think of energy. The higher orbit has higher energy with respect to the earth -- gravitational, and by virtue of comparing stable orbits, also kinetic. Dragon will "catch up" with the space station by converting some additional chemical energy (propellant) into kinetic energy, moving into and matching the station's orbit (and gaining the additional gravitational potential). (Or, given the small adjustment needed, perhaps mechanical energy, depending upon how the positional thrusters work -- compressed gas?)

Ugh, my physics classes are a long time away. Hope that's worded halfway comprehensibly.

Lower orbits have higher anglular velocity -- and it is angular velocity that dictates which craft gets ahead on orbit, because we're comparing angular position, not linear one.

For example, geostationary orbit (~36'000km radius) has period of 24h -- i.e., takes whole 24hours to cover all 360 degrees of rotation, having angular speed of 15deg/h, while Hubble's Space Telescope orbit (~560km radius) has period of 96minutes -- i.e., takes just over 1.5h to cover 360 degrees; with angular speed of 240deg/h.

Sure GEO has higher linear velocity and associated kinetic energy, but that's irrelevant.

I guess the Dragon was positioned under the Station so it gains the angular position slowly over time in a natural way.

Thanks. I felt I was missing something. I should have waited for the coffee to kick in.

I'll leave my comment as a warning to what age does to a person. ;-)

Looking at the screen with the cross-hairs it seems like the bottom right set of figures shows the distance to ISS, which was sitting at around 255m, and should go down to 235m (EDIT: was originally supposed to be 220m) before the crew on ISS tells dragon to head back to the 250m mark.

Here's hoping that they keep showing these shots from the ISS monitors throughout - kinda like watching someone coding but on a whole different level!

Another test done, now for a hold at 235m.

Does anyone know why this has been changed? I'd hazard a guess at dragon being slightly off the target position (slightly northwest), but haven't heard any commentary about why this may be.

I thought the planning and preparation would have some allowance for slight discrepancies, so are the changes to the planned points (220m to 250m) a part of this procedure, or would these "deltas" be a reactive response to real life?

"Station, Houston: You have a 'go' for capture."

I'll never forget these words.

That was great. Arm moving now!


Did you hear the part when he said "Looks like we have a dragon by the tail?" I cracked up.

Yes! Goosebumps.. But, I must unfortunately confess.. seeing all that unbranded space on the Dragon had me cynically thinking, how much could they sell that ad space for?

You know... Someday someone will put a Pan-Am logo there...

How hard would it be to procure the rights?

Many things would have to happen to make it possible:

- SpaceX would have to want to sell the ad space.

- If NASA is paying for the mission, they may want to have a word (most likely "no").

- The owners of the Pan-Am brand would probably appreciate the gift, but I'd like to make sure they won't get mad before any such stunt.

- The Arthur C. Clarke and Stanley Kubrick estates would also have something to say, after all, this is more or less a reference to 2001.

I'm kind of surprised that SpaceX didn't consider that for the outside of the dragon capsule.

Note that the capsule has a camera inside of it (there are pictures from it on SpaceX's site) so when the hatch opens you can see pictures directly from a video camera that isn't under NASA's control.

'Spacebook' needs to give you a call...:)

More details about this flight and what it's doing http://en.wikipedia.org/wiki/COTS_Demo_Flight_2

Map showing Dragon's real time position: http://www.n2yo.com/?s=38348

I watched the Nasa feed until 3am last night and now I'm up again watching it.

Seeing this gives me hope that we'll eventually get back to exploring the moon and space.

code. hack. code. hack. code. hack. watch spaceX make history. sleep. school. eat. code. hack.

You should think about adding showering to that list.

Most likely, he's working at home: http://bit.ly/9NiLQB

shower and interacting with real human beings hah

Nasa TV has a hidden video stream for their iPad app (http://liveips.nasa.gov.edgesuite.net/msfc/Wifi.m3u8), works great on Safari as well. Post here: http://t.co/b9jSxeqI

Remarkable. Three days after launch and they're about to hook up with a space station. One small step...

"two diameters to starboard" - to the right of the ISS? Or in the direction of the stars? :)

They are now looking at a capture time of ~9:40AM CT (about 90 minutes from this comment)

Anyone have any sort of commentary or chat? I can only stare at a blinking light for so long ...

They pipe up occasionally, just not so much idle banter, as they don't want to be talking when someone vital says something, and step all over it.

Like... (and i quote) "That's dragon passing over LA"

I waved. I saw my city from space, live. That was so cool!

Watching the Dragon approach from the point of view of the ISS is incredibly exciting in itself, but almost unbelievable when you think about the speeds they are flying at relative to the ground!

What's unbelievable about this? If I approach you on the ground we are both moving fast relative to center of the Earth. Or imagine us onboard the airplane.

It would be unbelievable if you approached me from the center of the earth, if you want to keep the same analogy :)

There was a moment when the Dragon had a speed of 0 in that frame of reference, what's unbelievable is the complexity of catching up to the ISS!

The capture is occurring about now. Link: http://www.nasa.gov/multimedia/nasatv/ustream.html

Just joined and heard that SpaceX had commanded Dragon to retreat from ISS. Can someone explain why? Also, what is the blinking section on the Dragon spacecraft?

Just a light, I believe it is used to detect the reflective panel on the ISS. But dragon is having a problem at and detecting a different reflector.

Thanks to Elon Musk for making transport to Low Earth Orbit boring :-). Now we can work towards doing more interesting things in space ;-)

9:56 ET Dragon was successfully captured!

Dragon over Atlantic http://i.imgur.com/WgCPA.jpg

Couple of people are discussing right now in #bitcoin on freenode if anyone wants to join :)

Update: #space seems to be more active.

In the next 30 minutes, they are planning to go from 150m out to 30m out. Should be dramatic to watch the capsule get closer.

I'm glued to watching this and doing very little work. I was born in 1969 and was fascinated by space as a kid, but then went off and did other things. To see this happening is wonderful but I have done screenshots of a number of places which would make dramatic and beautiful paintings

Now (8:00 AM EDT) they are saying capture time is planned for 9:10 AM EDT, so a bit over 1 more hour.

Final checks are complete, they are now go for capture with the robotic arm

Opened this with 1/2m to go - good timing

It's moving 5cm/s very carefully

Dragon now 30m below the ISS

Its captured the Dragon

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