Results for space walk
On this page:
 
Dictionary:

space walk


n.

An excursion by an astronaut outside a spacecraft in space; extravehicular activity.

spacewalk space walk v.
spacewalker space walker n.
 
 
Word Tutor: spacewalk
pronunciation

IN BRIEF: v. - Move outside the Earth's atmosphere while not in a craft.

 
WordNet: space walk
Note: click on a word meaning below to see its connections and related words.

The noun has one meaning:

Meaning #1: any kind of physical activity outside a spacecraft by one of the crew


 
Wikipedia: extra-vehicular activity
International Space Station assembly EVA made during the STS-116 spaceflight. Robert Curbeam with red stripes together with Christer Fuglesang over Cook Strait, New Zealand.
Enlarge
International Space Station assembly EVA made during the STS-116 spaceflight. Robert Curbeam with red stripes together with Christer Fuglesang over Cook Strait, New Zealand.

Extra-vehicular activity (EVA) is work done by an astronaut away from the Earth and outside of a spacecraft. The term most commonly applies to an EVA made outside a craft orbiting Earth (a spacewalk) but also applies to an EVA made on the surface of the Moon (a moonwalk). In the later lunar landing missions the command module pilot did an EVA to retrieve film canisters on the return trip.

Due to the different designs of the early spacecraft, the American and Soviet space programs also define an EVA differently. Russians define an EVA as occurring when a cosmonaut is in a vacuum. An American astronaut, in contrast, is not considered to have made an EVA until at least his head is outside the spacecraft.[dubious ] The term stand-up EVA (SEVA) is used for being partly outside.

EVAs may be either tethered (the astronaut is connected to the spacecraft, oxygen can be supplied through a tube, no propulsion is needed to return to the spacecraft) or untethered. When the tether performs life support functions such as providing oxygen, it is called an umbilical. For untethered EVAs during space flight, capability of returning to the spacecraft is essential; see Manned Maneuvering Unit (MMU) and Simplified Aid for EVA Rescue (SAFER).

EVA milestones

Stephen Robinson riding the robotic arm during STS-114.
  • The first EVA that was a moonwalk rather than a spacewalk was made by American astronaut Neil Armstrong on July 20 1969 when the Apollo 11 Lunar Module Eagle landed on the Moon. He was joined by crewmate Buzz Aldrin, and their EVA lasted 2 hours and 32 minutes.
  • Anatoly Solovyev, with 16 spacewalks, totaling 77 hours, 41 minutes EVA, holds the records for most spacewalks and greatest duration on EVA.
  • Captain Michael Lopez-Alegria holds the all time American record for number of EVA's (10) and total EVA duration (67 hours and 40 minutes).

EVA hazards

During an untethered EVA the astronaut is far from help.
Enlarge
During an untethered EVA the astronaut is far from help.
Tear in glove during STS-118
Enlarge
Tear in glove during STS-118

An EVA is dangerous for a number of different reasons. The primary one is collision with space debris. Orbital velocity at 300 km above the Earth (typical for a Space Shuttle mission) is 7.7 km/s. This is 10 times the speed of a bullet, so the kinetic energy of a small particle with a mass 1/100th that of a bullet (e.g. a fleck of paint or a grain of sand) is equal to that of a bullet. Every space mission creates more orbiting debris, so this problem will continue to worsen (see also Kessler Syndrome).

Another reason for danger is that external environments in space are harder to simulate before the mission, though approximate simulations can be achieved at facilities like NASA's Neutral Buoyancy Laboratory. Space walks are avoided for routine tasks because of their danger. As a result the EVAs are often planned late in the project development when problems are discovered, or sometimes even during an operational mission. The exceptional danger involved in EVAs inevitably leads to emotional pressures on astronauts.

Other possible problems include a space walker becoming separated from his or her craft or suffering a spacesuit puncture which would depressurize the suit, causing anoxia and rapid death if the space walker is not brought into a pressurized spacecraft quickly.

One astronaut has suffered a spacesuit puncture. During STS-37, a small rod punctured the glove of one of the astronauts (the name is undisclosed, but it was either Jerry L. Ross or Jay Apt). However, the puncturing object, which stabbed the astronaut's hand as well, held in place, resulting in no detectable depressurization. In fact, the puncture was not noticed until after the space walkers were safely back inside Atlantis.[1]

Astronaut Bruce McCandless on an untethered EVA.
Enlarge
Astronaut Bruce McCandless on an untethered EVA.

Aleksei Leonov's EVA did not pass smoothly, although this was not reported at the time. During the EVA, Leonov's suit had become overinflated to the point he could longer re-enter and seal the door of the airlock. Because he was breathing pure oxygen, he was able to reduce his suit pressure to under 4 psi (28 kPa) [1] and, with much effort, climb back inside.

For EVAs from ISS NASA now routinely employs a camp out procedure to reduce the risk of decompression sickness. This was first tested by the Expedition 12 crew. During a camp out, astronauts shut themselves in the airlock and lower the air pressure to 10.2 psi (70 kPa). The station is kept at 14.7 psi (101 kPa); spending a night at the lower air pressure helps flush nitrogen from the body, thereby preventing "the bends."[2][3]

As of 2007, no catastrophic incident has ever occurred during an extra-vehicular activity, and no astronaut or cosmonaut has ever died during one. However, given the considerable hazards inherent in EVAs, and the resultant risk to astronauts, some scientists are working to develop tele-operated robots for outside construction work, to potentially eliminate or reduce the need for human EVAs.

2007 EVAs

This is a list of EVAs conducted or scheduled to be conducted in 2007.


See also: List of spacewalks and moonwalks  and List of ISS spacewalks
Spacewalk
Start time
End time Duration Spacewalker Spacecraft or
Space station
Mission/
Function
Outcome Remarks
January 31, 15:14 GMT January 31, 23:09 GMT 7 hours, 55 minutes Michael Lopez-Alegria
ISS (Quest)
Second Expedition 14 EVA - reroute ISS cooling lines.[4]
success
Sunita Williams
February 4, 13:38 GMT February 4, 20:49 GMT 7 hours, 11 minutes Michael Lopez-Alegria
ISS (Quest)
Third Expedition 14 EVA - reroute ISS cooling lines.[5]
success
precautionary decontamination conducted at end due to ammonia flakes seen earlier.
Sunita Williams
February 8, 13:26 GMT February 8, 20:06 GMT 6 hours, 40 minutes Michael Lopez-Alegria
ISS (Quest)
Fourth Expedition 14 EVA - jettison shrouds; prep for cargo carriers; connect cables for SSPTS[6]
success
Fourth EVA for Williams is the most for any woman; Lopez-Alegria sets U.S. record for cumulative EVA time
Sunita Williams
February 22, 10:27 GMT February 22, 16:45 GMT 6 hours, 18 minutes Michael Lopez-Alegria
ISS (Quest)
Fifth Expedition 14 EVA - Progress antenna retraction; photography of Russian satellite antenna; Russian experiment changeout; Automated Transfer Vehicle (ATV) antenna photography/inspection; German experiment photography; Strela crane photography/inspection.[7]
success
Mikhail Tyurin
30 May, 19:05 GMT 31 May, 00:30 GMT 5 hours, 25 minutes Oleg Kotov
ISS (Pirs)
First Expedition 15 EVA - install protective panels to shield ISS from space debris.[8]
success
started 45 minutes late due to communications issues.
Fyodor Yurchikhin
6 June, 14:23 GMT 6 June, 20:00 GMT 5 hours, 37 minutes Oleg Kotov
ISS (Pirs)
Second Expedition 15 EVA - install Biorisk experiment; install ethernet cable; install more debris panels.[9]
success
15 minutes faster than planned
Fyodor Yurchikhin
11 June, 20:02 GMT 12 June, 02:17 GMT 6 hours, 15 minutes James F. Reilly
ISS (Quest)
First STS-117 EVA - connect S3/S4 bolts, cables and connectors; prepare for deployment solar arrays.[10]
success
started late due to loss of CMG attitude control
John D. Olivas
13 June, 18:28 GMT 14 June, 01:44 GMT 7 hours, 16 minutes Patrick G. Forrester
ISS (Quest)
Second STS-117 EVA - assist with P6 solar array retraction; prep SARJ for rotation[11]
partial success
SARJ launch restraints still in place
Steven Swanson
15 June, 17:24 GMT 16 June, 01:22 GMT 7 hours, 58 minutes James F. Reilly
ISS (Quest)
Third STS-117 EVA - OMS blanket repair; install H2 vent valve for OGS; P-6 SAW retraction[12]
success
John D. Olivas
17 June, 16:25 GMT 17 June, 22:54 GMT 6 hours, 29 minutes Patrick G. Forrester
ISS (Quest)
Fourth STS-117 EVA - SARJ activation; cable install on Unity; GPS antenna removal; debris shield install on Destiny
success
Steven Swanson
23 July, 10:25 GMT 23 July, 18:06 GMT 7 hours, 41 minutes Clayton Anderson
ISS (Quest)
Third Expedition 15 EVA (aka EVA-9) - replace component for mobile transporter redundant power; jettison ammonia tank and flight support equipment; clean CBM on nadir Unity port.[13][14]
success
Fyodor Yurchikhin
11 August, 16:28 GMT 11 August, 22:45 GMT 6 hours, 17 minutes Richard Mastracchio
ISS (Quest)
First STS-118 EVA - S5 installation; P6 Radiator retraction and cinch.
success
Dafydd Williams
13 August, 15:32  GMT 13 August, 22:00 GMT 6 hours, 28 minutes Richard Mastracchio
ISS (Quest)
Second STS-118 EVA - Failed CMG removal; new CMG installation.
success
Dafydd Williams
15 August, 14:37 GMT 15 August, 20:05 GMT 5 hours, 28 minutes Richard Mastracchio
ISS (Quest)
Third STS-118 EVA - SASA relocation; CETA Cart relocation; P6 Transponder retrieval. S-band antenna relocation from P6 to P1.
success
Ended early due to possible hole in Mastracchio's glove. All but one activity completed.
Clayton Anderson
18 August, 14:17 GMT 18 August, 19:19 GMT 5 hours, 02 minutes Dafydd Williams
ISS (Quest)
Fourth STS-118 EVA - OBSS Boom Stand Installation; MISSE retrieval; EWIS Antenna Installation; Secured Z1 gimbal locks
success
EVA plan altered due to Hurricane Dean (2007), planned shorter EVA for early undocking.
Clayton Anderson

See also

References

External links

Wikimedia Commons has media related to:

 
Translations: Translations for: Spacewalk

Dansk (Danish)
n. - rumvandring
v. intr. - gå på rumvandring, vandre i rummet

Français (French)
n. - (Aérosp) sortie dans l'espace
v. intr. - sortir dans l'espace

Deutsch (German)
n. - Spaziergang im Weltraum
v. - im Weltraum spazierengehen

Ελληνική (Greek)
n. - περίπατος στο διάστημα
v. - περπατώ στο διάστημα

Italiano (Italian)
passeggiata spaziale, fare una passeggiata spaziale

Português (Portuguese)
n. - passeio espacial (do astronauta fora da nave)
v. - mover-se de um lado para outro no espaço

Русский (Russian)
выход в открытый космос

Español (Spanish)
n. - paseo espacial
v. intr. - efectuar actividad física fuera de la nave espacial

Svenska (Swedish)
n. - rymdpromenad
v. - att färdas i rymden

中文(简体) (Chinese (Simplified))
太空漫步, 航天舱外活动, 在太空中行走, 进行舱外活动

中文(繁體) (Chinese (Traditional))
n. - 太空漫步, 航天艙外活動
v. intr. - 在太空中行走, 進行艙外活動

한국어 (Korean)
n. - 우주 유영
v. intr. - 우주 유영을 하다

日本語 (Japanese)
n. - 宇宙遊泳

עברית (Hebrew)
n. - ‮הליכה בחלל, טיול בחלל‬
v. intr. - ‮נע בחלל‬


 
 

Join the WikiAnswers Q&A community. Post a question or answer questions about "space walk" at WikiAnswers.

 

Copyrights:

Dictionary. The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2007. Published by Houghton Mifflin Company. All rights reserved.  Read more
Word Tutor. Copyright © 2004-present by eSpindle Learning, a 501(c) nonprofit organization. All rights reserved.
eSpindle provides personalized spelling and vocabulary tutoring online; free trial Read more
WordNet. WordNet 1.7.1 Copyright © 2001 by Princeton University. All rights reserved.  Read more
Wikipedia. This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Extra-vehicular activity" Read more
Translations. Copyright © 2007, WizCom Technologies Ltd. All rights reserved.  Read more

Search for answers directly from your browser with the FREE Answers.com Toolbar!  
Click here to download now. 

Get Answers your way! Check out all our free tools and products.

On this page:   E-mail   print Print  Link  

 

Keep Reading

Mentioned In: