|
Sunday, March 26, 2017
Лучшие статьи за неделю от Naked Science
Sunday, March 19, 2017
Лучшие статьи за неделю от Naked Science
|
Saturday, March 18, 2017
1st Spacewalk Takes Place, March 18, 1965
NASA had been gearing up to be the first to perform such extra-vehicular activity (EVA), but the Soviets, as they had with the first satellite and first man in space, beat the US to it.
With Apollo missions in mind, NASA spun the Gemini program off to develop the capability for astronauts to work outside a two-man Earth orbiting spacecraft. To compete, the Soviet Union hastily converted its single-pilot Vostok capsule into a two- or three-person craft named Voskhod. The Soviets were able to launch two Voskhod capsules before the first manned Gemini was launched.
Being first doesn’t always mean being the best and the Soviets' avionics technology at the time was not as advanced as that of the United States. The Voskhod cabin could not have been left depressurized by an open hatch or the air-cooled electronics would have overheated. So spacewalking cosmonauts would have to enter and exit the spacecraft through an airlock, unlike the Gemini capsules that did not require airlock as they were designed so the cabin could be exposed to the vacuum of space when one of two large hatches was opened and both the spacewalking astronaut and the command pilot were in vacuum during the EVA.
The patch of the Voskhod-2 manned space mission celebrated the first spacewalk.
During his 12 minute walk, Leonov had no means to control his motion other than pulling on his 50.7-foot tether. Leonov’s spacesuit ballooned from its internal pressure against the vacuum of space, stiffening so much that he could not activate the shutter on his chest-mounted camera.
Even worse, Leonov's spacesuit had inflated in the vacuum of space to the point where he could not re-enter the airlock. He opened a valve to allow some of the suit's pressure to bleed off, and was barely able to get back inside the capsule.
Leonov had spent some 18 months undergoing intensive weightlessness training for the mission. It would be almost four years before the Soviets tried another EVA.
The first American spacewalk was performed on June 3, 1965, by Edward H White, II from the second manned Gemini flight, Gemini 4, for 21 minutes, on a 25-foot tether (see photo below). Like the Soviets’ adventure, this EVA was not without issue. A defect in the capsule's hatch latching mechanism caused difficulties opening and closing the hatch, which delayed the start of the EVA and put White and his crewmate at risk of not getting back to Earth alive.
Both the US and Soviet Union concealed most of the issues they encountered when taking these first spacewalks until after the end of the Cold War. Some such secrets are revealed in a 2006 dual biography / history of the Space Race written by Leonov and former American astronaut David Scott entitled Two Sides of the Moon: Our Story of the Cold War Space Race. Neil Armstrong and Tom Hanks both wrote introductions to the book.
Also see:
- 1st untethered spacewalk is taken, February 7, 1984
- NASA’s Gemini 4 launches, June 3, 1965
- Sputnik 1 launches, October, 4, 1957
- 1st human killed in spaceflight, April 24, 1967
- Soyuz 5 launches, January 15, 1969
- Russia in Space
- NASA: Revealing the unknown to benefit all humankind
For more moments in tech history, see this blog. EDN strives to be historically accurate with these postings. Should you see an error, please notify us.
Thursday, January 19, 2017
What is its speed VP when the planet passes the perigee?
Tuesday, January 10, 2017
Erwin Rudolf Josef Alexander Schrödinger
Четыре факта о квантовой физике, о которых не рассказывают | https://t.co/03qvwTvhqD https://t.co/AN5KVbvPUg
— HeyClick Net (@heyclicknet) January 10, 2017
Monday, January 9, 2017
Quantization as an eigenvalue problem (First communication)
https://t.co/xrW17gfo65 #КВАНТОВАНИЕ КАК #ЗАДАЧА О #СОБСТВЕННЫХ #ЗНАЧЕНИЯХ #первое #сообщение #Шрёдинеер #Цюрих Поступило 27 января #1926г. pic.twitter.com/hgZGRkts7c
— HeyClick Net (@heyclicknet) January 10, 2017