Astronaut takes spacewalk right before setting US record

Five Incredible Facts About Scott Kelly's Nearly Year-Long Space Mission

CAPE CANAVERAL, Fla. (AP) -- NASA's yearlong spaceman, Scott Kelly, took his first spacewalk Wednesday just hours before setting a new U.S. flight record.

Kelly and Kjell Lindgren floated out of the International Space Station for a bit of maintenance work. Their to-do list included greasing the station's big robot arm, routing cables, removing insulation from an electronic switching unit and covering an antimatter and dark matter detector.

Kelly's identical twin, Mark, a retired astronaut, urged his brother to be careful but still have fun outside.

"Don't forget to take a good selfie!" Mark said via Twitter. He commanded the mission that delivered the antimatter-hunting Alpha Magnetic Spectrometer in 2011; it was the next-to-last shuttle flight. Scientists want the device covered with a thermal blanket to keep it cooler and prolong its life.

The spacewalk was held up slightly after Lindgren inadvertently switched on the water flow in his suit too soon. Mission Control wanted to make certain the suit would be safe, before giving the all-clear. Water is needed to cool the suit; a malfunction two years ago caused a spacewalker's helmet to flood and almost drowned him.

See photos from Scott Kelly's year in space:

55 PHOTOS
Astronaut Scott Kelly's #YearInSpace in tweets
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Astronaut takes spacewalk right before setting US record
On the grid! Back from #spacewalk & tweet ability down. Real-life lesson in importance of connectivity. #YearInSpace https://t.co/VMc1VwRhzZ
For an instant before sunrise, the space station glows orange. #GoodMorning from @Space_Station! #YearInSpace https://t.co/FEXx8Rezg3
Day 222. Sleep by the light of the #moon. #GoodNight from @space_station! #YearInSpace https://t.co/WOP7jjs7mb
Day 219. The #sun will come out 16 times tomorrow. #GoodNight from @space_station! #YearInSpace https://t.co/jvQp2fkV4O
Day 218 Bewitching hour on #Earth. Have fun, be safe. #HappyHalloween & #GoodNight from @space_station! #YearInSpace https://t.co/5Uj6fWHte0
#Halloween #EarthArt Some places of our world look other worldly. Boo! #YearInSpace https://t.co/CwT86NtR5Y
#Halloween #EarthArt Ghostly and dark but beautiful too. #YearInSpace https://t.co/uaHGt9jk6g
#TropicalStorm #Ashobaa churns off the coast of #Oman. Stay safe down there. #YearInSpace https://t.co/7047MGIymT
Day 216. Seeing our world in a new light tonight. #GoodNight from @space_station! #YearInSpace https://t.co/ih0wnSQXyG
#SpaceWalkSelfie Back on the grid! Great first spacewalk yesterday. Now on to the next one next week. #YearInSpace https://t.co/7qXLiKzaKA
Day 211. Night calling #SouthAfrica like it is calling me. #GoodNight from @space_station! #YearInSpace https://t.co/xK4FJlh9ei
Hurricane #Patricia approaches #Mexico. It's massive. Be careful! #YearInSpace https://t.co/F5LgnjOjey
Great Scott!10/21/15! Fly cars? I live in a flying house! 17,500MPH in 1.21 Jigawatts over Hill Valley, CA #BTTF2015 https://t.co/PAErx6PaQI
The area to the North and East of the #Himalayas is strikingly beautiful. #YearInSpace http://t.co/QEHLK2PcIX
The atmosphere sometimes she glows. #GoodMorning from @Space_Station! #YearInSpace http://t.co/dQ93kZbwpw
#EarthArt Across the Greatest Desert- #Sahara #YearInSpace http://t.co/1OW6IZNGKJ
#EarthArt A single pass over the #Australian continent. Picture 15 of 17. #YearInSpace http://t.co/ESzOODFzB2
Day 200. Sometimes a little light makes all the difference. #GoodNight from @Space_Station #YearInSpace http://t.co/qkFtdtKLkb
#EarthArt A single pass over the #Australian continent. Picture 10 of 17. #YearInSpace http://t.co/NjwuEzgD0Z
#EarthArt in one pass over the #Australian continent. Picture 1 of 17. #YearInSpace http://t.co/LvQCauUEpT
The daily morning dose of #aurora to help wake you up. #GoodMorning from @Space_Station! #YearInSpace http://t.co/Ar6ScCbUPo
#Houston, looks like great weather down there! Although, I'd be fine with any weather. #GoodMorning! #YearInSpace http://t.co/07GQFT4vrM
Day 191. From one #sunrise to the next. Good night from @space_station! #YearInSpace http://t.co/iablXOZO1g
Early morning shot of Hurricane #Joaquin from @space_station before reaching #Bahamas. Hope all is safe. #YearInSpace http://t.co/3dlwOzU2eq
Feel bad for the people of #NorthKorea when I see with my own eyes they live without electricity. #YearInSpace http://t.co/E28PWvEajV
#EarthArt In 377 cumulative days in space, I've never seen this before today. #YearInSpace http://t.co/j4O0RpchD9
Day 180. Moonlight over Italy. #BuonaNotte Good night from @space_station! #YearInSpace http://t.co/du1uNThgDk
#GoodMorning to the Holy City of #Mecca #Makkah! #YearInSpace http://t.co/pEeRKPla0G
Day 179. The #Nile at night is a beautiful sight for these sore eyes. Good night from @space_station! #YearInSpace http://t.co/eAMBZ9p428
#EarthArt Half a year, still she dazzles, colors, intrigues, excites, amuses, interests and shines. #YearInSpace http://t.co/m8eijSS8pq
Day 190. Clouds bathe #Europe in a cool glow. #Goodnight from @Space_Station! #YearInSpace http://t.co/g9ZYOyTb27
Day 166. #Venus photobombed the #Moon tonight. Good night from @space_station! #YearInSpace http://t.co/9lRdYn1rbE
Day 165. On the number of stars in our #MilkyWay galaxy, mind blown. Good night from @space_station! #YearInSpace http://t.co/piphlpemRE
My colleague @Astro_Kimiya took this photo of the eye of this Eastern Pacific typhoon. Impressive! #YearInSpace. http://t.co/uU5tZnap7R
Another pass through #Aurora. The sun is very active today, apparently. #YearInSpace http://t.co/1uDtRzrGuY
Tomorrow we'll eat the anticipated veggie harvest on @space_station! But first, lettuce take a #selfie. #YearInSpace http://t.co/fUKQMhEDjK
Day 127. Sunset returns! Perfect end. Thanks again for joining me today. Good night from @space_station! #YearInSpace http://t.co/qFGNapGIl3
#GoodMorning #Barcelona, #Spain! Looking beautiful as usual from @Space_Station. #YearInSpace http://t.co/P448JdLr78
#Goodevening #Japan. Showing @Astro_Kimiya how to take pictures of #Earth at night. #YearInSpace http://t.co/0UpTnVtdVK
#Bahamas, the strokes of your watercolors are always a refreshing sight. #YearInSpace. http://t.co/ISASTDak90
#Athens, #Greece, #GoodMorning from @Space_Station. Wishing you the best. #YearInSpace http://t.co/zAMEz5JvlW
Good morning from 250 miles above the African desert. #YearInSpace http://t.co/wE0KrGDfdN
Stars and stripes from @Space_Station. Happy #NationalFlagDay! #YearInSpace http://t.co/0jlup7w6Ij
I don't know where in the US Southwest this is, but it sure is beautiful. #YearInSpace http://t.co/lmaUEOS8Eg
Subtropical Storm #Ana churns off the East coast of USA. #Wx from @Space_Station. #YearInSpace http://t.co/uaMRGDO8JG
Had my first cup of fancy coffee yesterday from the much anticipated @Space_Station #espresso machine. Not too bad. http://t.co/tpnHyTczul
Parts of #Canada look like a cracked window this #Sunday as the ice melts. #YearInSpace http://t.co/rUmrtPs6s2
#SaturdayMorning #coffee with my old friend #PlanetEarth. #YearInSpace http://t.co/zmKmVBCuLk
Sometimes #Earth looks like another planet from @Space_Station. #YearInSpace http://t.co/NKQC6egnBP
Good morning from #ISS. This high altitude Central Asian lake looks like my morning cereal. #BreakfastOfChampions http://t.co/htJZP1CoGF
Sometimes the #world seems to shimmer. #YearInSpace http://t.co/ttGibGTW2Z
#Himalayas. What icy veins you have. #YearInSpace http://t.co/C94vLDu3jy
@AstroTerry and I celebrating #OpeningDay and the #Astros and #Orioles being tied for 1st place! #MLB. #YearInSpace http://t.co/DAzBFUEkQ7
Good morning #Texas from the #ISS. Looks like #Houston and #Austin have some #weather headed your way. #YearInSpace http://t.co/boDVsCY9vX
.@FLOTUS Thank you. Made it! Moving into crew quarters on @space_station to begin my #yearinspace. http://t.co/jhoj7ltaV6
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A second spacewalk - to further whittle down a backlog of station chores - will be conducted Nov. 6 by the same two men.

In the wee hours of Thursday morning, just after midnight Eastern Time, Kelly will break the American record for NASA's longest single space shot. That 215-day record - more than seven months - was set in 2007.

Kelly has been living at the orbiting lab since March. He'll remain there until March 2016. Russian Mikhail Kornienko is also part of the one-year experiment in preparation for eventual Mars expeditions, although it will fall shy of the 14-month world record held by a fellow cosmonaut, Valery Polyakov, who lived on Russia's old Mir space station in 1994 and 1995.

Former space station resident Michael Lopez-Alegria has been counting down the days until Kelly surpasses his record of 215 days, eight hours and 22 minutes. "The countdown clock is ticking," he said last week in a tweet.

President Barack Obama already has relayed congratulations. In a phone call last week, Obama told Kelly his feat is "nothing to sneeze at." Kelly assured the president that even though he feels like he's been in orbit a long time and still has a long way to go, "it shouldn't be a problem getting to the end with enough energy and enthusiasm to complete the job."

"Records are made to be broken," Kelly noted.

Earlier this month, Kelly broke the U.S. record for the most accumulative time in space: 383 days and counting over four missions. It will total 522 days by the time he returns to Earth, well short of the Russian record.

See photos of Scott Kelly through the years:
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Astronaut Scott Kelly through the years
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Astronaut takes spacewalk right before setting US record
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