Watch the SpaceX Dragon Leave the Space Station

3 minute read

Nothing, absolutely nothing, is easy in space, and that includes leaving it, as the crew of the International Space Station (ISS) will be reminded on Thursday morning, May 21, when the Dragon cargo vessel undocks and heads home—a maneuver TIME will live-stream via NASA beginning at 6:45 a.m. ET. Dragon, the 24-ft. (7.3 m) cargo vehicle built by SpaceX, arrived at the ISS on April 17 carrying 5,200 lbs (2,360 kg) of cargo. It is returning after a five-week stay, bringing home 3,100 (1,400 kg) different lbs. of stuff—some of it trash, but a lot of it scientific samples that are part of the extensive biomedical studies being conducted on astronaut Scott Kelly and cosmonaut Misha Kornienko as they spend a marathon year in space.

No spacecraft leaving the ISS can simply cast off and go. Ever since the long-ago joint mission of Gemini VI and Gemini VII, 50 years ago this December, when the two manned spacecraft maneuvered to within inches of each other, NASA has appreciated the delicate dance involved when any two orbiting objects come anywhere near each other. Moving along at a matching 17,500 mph (28,160 k/g), the ships are effectively motionless relative to each other. If one adds even the tiniest bit of speed that the other one doesn’t match—going to, say 17,505 mph—the result can be a fender bender.

For that reason, the Dragon departure will be a process that will consume a whole morning’s work. Before 7 a.m., the station’s 58 ft. (17.6 m) robotic arm will grapple the Dragon, which will decouple from its berth on the station’s Harmony module. The arm will carry the Dragon as far from the station as it can, and Kelly, who will be controlling the operation from aboard, will give the signal for its release at 7:04 a.m. Over the course of the next four hours and 45 minutes, the Dragon will fire its thrusters three separate times, edging further away from the station until, at 11:49 a.m., it reaches the precise spot in its orbit to begin a reentry burn that will carry it to a Pacific splashdown at 12:42 p.m.

The station has been serviced by milk runs like these many times in the 15 years it has been continually occupied and there will be a lot more to come in the decade or so of service it has left to it. It’s a measure of the complexity of the up and down trips that they take so much planning and such deft execution; it’s a measure of the people doing the executing that the maneuvers can actually, after a time, seem routine.

See Scott Kelly's First 30 Days in Space

Good guesses on my 1st #SpaceGeo pic! I'll announce the winner Friday. Do you know your geo? http://1.usa.gov/1bw0Xuh
Scott Kelly has posted a photo almost every day since arriving at the ISS. Here, see a selection from his first 30 days in space. (Via Twitter on April 23, 2015)Scott Kelly—NASA
Was asked what I write down on this small kneeboard. Mostly hardware serial numbers and #ISS locations. #YearInSpace
"Was asked what I write down on this small kneeboard. Mostly hardware serial numbers and #ISS locations. #YearInSpace" - via Twitter on April 28, 2015Scott Kelly—NASA
I wonder what they do here. #NorthAfrica #YearInSpace
"I wonder what they do here. #NorthAfrica #YearInSpace" - via Twitter April 27, 2015Scott Kelly—NASA
Looks serene from @Space_Station, but my thoughts are still with the people affected by the #NepalEarthquake.
"Looks serene from @Space_Station, but my thoughts are still with the people affected by the #NepalEarthquake." - via Twitter on April 26, 2015Scott Kelly—NASA
#Movie night in micro #Gravity aboard #ISS on our new HD projector which we use for conferences, tech software, etc..
"#Movie night in micro #Gravity aboard #ISS on our new HD projector which we use for conferences, tech software, etc.." - via Twitter on April 25, 2015Scott Kelly—NASA
My #bedroom aboard #ISS. All the comforts of #home. Well, most of them. #YearInSpace
"My #bedroom aboard #ISS. All the comforts of #home. Well, most of them. #YearInSpace" - via Twitter on April 24, 2015Scott Kelly—NASA
#EarthObservations Window on the world. Studying our planet from the cupola on @space_station #NoPlaceLikeHome
"#EarthObservations Window on the world. Studying our planet from the cupola on @space_station #NoPlaceLikeHome" - via Twitter on April 22, 2015Scott Kelly—NASA
Blown away by a dust swept #RedSea. Good morning from the @space_station!  #YearInSpace.
"Blown away by a dust swept #RedSea. Good morning from the @space_station! #YearInSpace." - via Twitter on April 21, 2015Scott Kelly—NASA
#Calcutta area shimmers in the sunlight. #YearInSpace
"#Calcutta area shimmers in the sunlight. #YearInSpace" - via Twitter on April 20, 2015Scott Kelly—NASA
Africa. I wonder what these desert sands look like up close?#YearInSpace
"Africa. I wonder what these desert sands look like up close?#YearInSpace" - via Twitter on April 19, 2015Scott Kelly—NASA
Working on #ISS research today & how micro gravity impacts aging and muscles of the C Elegan roundworm. #YearInSpace
"Working on #ISS research today & how micro gravity impacts aging and muscles of the C Elegan roundworm. #YearInSpace" - via Twitter on April 18, 2015NASA
Great job @AstroSamantha and @AstroTerry capturing #SpaceX Dragon this morning! #YearInSpace
"Great job @AstroSamantha and @AstroTerry capturing #SpaceX Dragon this morning! #YearInSpace" - via Twitter on April 17, 2015Scott Kelly—NASA
The varied colors of #Madagascar. #YearInSpace
"The varied colors of #Madagascar. #YearInSpace" - via Twitter on April 16, 2015Scott Kelly—NASA
Sometimes the #world seems to shimmer. #YearInSpace
"Sometimes the #world seems to shimmer. #YearInSpace" - via Twitter on April 15, 2015Scott Kelly—NASA
Congrats @SpaceX and @NASA team on a successful launch! Watched with my crewmates aboard #ISS. #YearInSpace
"Congrats @SpaceX and @NASA team on a successful launch! Watched with my crewmates aboard #ISS. #YearInSpace" - via Twitter on April 14, 2015Scott Kelly—NASA
This #butterfly caught my eye while flying high above the #gulfofmexico. #YearInSpace
"This #butterfly caught my eye while flying high above the #gulfofmexico. #YearInSpace" - via Twitter on April 13, 2015Scott Kelly—NASA
Not sure what is going on on this beach in #Mexico but it's a striking image. #YearInSpace
"Not sure what is going on on this beach in #Mexico but it's a striking image. #YearInSpace" - via Twitter on April 12, 2015Scott Kelly—NASA
#Earth is breathtaking. #YearInSpace
"#Earth is breathtaking. #YearInSpace" - via Twitter on April 11, 2015Scott Kelly—NASA
Hopefully this is pollen or algae and not something man made. #YearInSpace
"Hopefully this is pollen or algae and not something man made. #YearInSpace" - via Twitter on April 10, 2015Scott Kelly—NASA
Madagascar drains its red mud into the Indian Ocean. #YearInSpace
"Madagascar drains its red mud into the Indian Ocean. #YearInSpace" - via Twitter on April 9, 2015Scott Kelly—NASA
Looks messy, but it's functional. Our #food table on the @space station. What's for breakfast? #YearInSpace
"Looks messy, but it's functional. Our #food table on the @space station. What's for breakfast? #YearInSpace" - via Twitter on April 8, 2015Scott Kelly—NASA
#Patagonia never disappoints. #YearInSpace
"#Patagonia never disappoints. #YearInSpace" - via Twitter on April 7, 2015Scott Kelly—NASA
#Australia. You are very beautiful. Thanks for being there to brighten our day. #YearInSpace
"#Australia. You are very beautiful. Thanks for being there to brighten our day. #YearInSpace" - via Twitter on April 6, 2015Scott Kelly—NASA
Good morning Southern #Florida from the #ISS. #YearInSpace
"Good morning Southern #Florida from the #ISS. #YearInSpace" - via Twitter on April 5, 2015Scott Kelly—NASA
Enjoying Saturday evening dinner with @AstroTerry on the #ISS
"Enjoying Saturday evening dinner with @AstroTerry on the #ISS" - via Twitter on April 4, 2015NASA
#FlashbackFriday Got my 1st EMT training at 16. Emergency medical training on #ISS keeps me 35 years proficient.
"#FlashbackFriday Got my 1st EMT training at 16. Emergency medical training on #ISS keeps me 35 years proficient." - via Twitter on April 3, 2015Scott Kelly—NASA
.@FLOTUS Thank you. Made it! Moving into crew quarters on @space_station to begin my #yearinspace.
".@FLOTUS Thank you. Made it! Moving into crew quarters on @space_station to begin my #yearinspace." - via Twitter on March 30, 2015Scott Kelly—NASA

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Write to Jeffrey Kluger at jeffrey.kluger@time.com