SAFER Makes Safe to Walk in Space

SAFER Makes Safe to Walk in Space Its like a scene from a science fiction movie nightmare: an astronaut is working outside a spacecraft in the vacuum of space when something happens. A tether breaks or maybe a computer glitch strands the astronaut too far from the ship. However it happens, the end result is the same. The astronaut ends up floating away from the spacecraft into the endless void of space, with no hope of rescue. Thankfully, NASA developed a device for space walking that keeps an astronaut safe while working outdoors to prevent such a scenario from happening in real life.   Safety for EVAs Space walks, or extravehicular activities (EVAs), are an important part of living and working in space. Dozens were needed just for the the assembly of the International Space Station (ISS).   Early missions by both the U.S. and Soviet Union also relied on space walks, with astronauts tethered to their spacecraft by lifelines. The space station cannot maneuver to rescue a free-floating EVA crew member, so NASA got to work to design a safety harness for astronauts who would be working around it without direct connections. Its called Simplified Aid For EVA Rescue (SAFER): a life jacket for space walks. SAFER is a self-contained maneuvering unit worn by astronauts like a backpack. The system relies on small nitrogen-jet thrusters to let an astronaut move around in space. Its relatively small size and weight allow for convenient storage on the station, and let EVA crew members put it on in the station’s airlock. However, the small size was achieved by limiting the amount of propellant it carries, meaning that it can only be used for a limited time. Its intended primarily for emergency rescue, and not as an alternative to tethers, and safety grips. Astronauts control the unit with a hand controller attached to the front of their space suits, and computers assist in its operation. The system has an automatic attitude hold function, in which the onboard computer helps the wearer maintain course. SAFERs propulsion is provided by 24 fixed-position thrusters that expel nitrogen gas and have a thrust of 3.56 Newtons (0.8 pounds) each. SAFER was first tested in 1994 aboard the space shuttle Discovery, when astronaut Mark Lee became the first person in 10 years to float freely in space. EVAs and Safety Space walking has come a long way since the early days. In June 1965, astronaut Ed White became the first American to conduct a space walk. His space suit was smaller than later EVA suits, since it did not carry its own oxygen supply. Instead, a hose to an oxygen supply on the Gemini capsule connected White. Bundled with the oxygen hose were electrical and communication wires and a safety tether. However, it quickly expended its supply of gas. On Gemini 10 and 11, a hose to a nitrogen tank aboard the spacecraft connected a modified version of the handheld device. This allowed the astronauts to use it for a longer period of time. The Moon missions had EVAs starting with Apollo 11, but these were on the surface, and required the astronauts wear full space suits. Skylab astronauts made repairs to their systems, but were tethered to the station. In later years, especially during the shuttle era, the Manned Maneuvering Unit (MMU) was used as a way for an astronaut to jet around the shuttle. Bruce McCandless was the first to try one out, and the image of him floating free in space was an instant hit.   SAFER, which has been described as a simplified version of the MMU, has two advantages over the earlier system. It is a more convenient size and weight and ideal for an astronaut rescue device outside the Space Station. SAFER is a rare type of technology- the kind NASA built hoping that it wont be necessary to use it. So far, tethers, safety grips, and the robot arm have proved adequate to safely keep astronauts where they are supposed to be during space walks. But if they ever fail, SAFER will be ready.

The Word of the Year 2011

The Word of the Year 2011 The Word of the Year 2011 The Word of the Year 2011 By Mark Nichol Each year at about this time, the English-language media rolls out various reports announcing the word of the year according to one or more authorities. These pieces imply or overtly suggest that these selections are keywords for our society’s values, beliefs, and obsessions. But a glance at such choices reveals that these words are the linguistic equivalent of candy satisfying (or not sometimes they’re the equivalent of chocolate-covered brussels sprouts) but not sustaining. The following lists of the top word for each year of the past decade suggest that one year’s byword can be the next year’s punch line (or a least a later period’s â€Å"Huh?†): Merriam-Webster 2010: austerity 2009: admonish 2008: bailout 2007: w00t 2006: truthiness 2005: integrity 2004: blog 2003: democracy American Dialect Society 2010: app 2009: tweet 2008: bailout 2007: subprime 2006: plutoed 2005: truthiness 2004: red state/blue state 2003: metrosexual 2002: weapons of mass destruction 2001: 9-11 (most often styled 9/11) Global Language Monitor 2011: occupy 2010: spillcam 2009: Twitter 2008: change 2007: hybrid 2006: sustainable 2005: refugee 2004: incivility 2003: embedded 2002: misunderestimate 2001: ground zero Oxford Dictionaries 2011: squeezed middle 2010: big society 2009: unfriend 2008: credit crunch 2007: footprint 2006: bovvered 2005: podcast 2004: chav Technological terms like app and tweet have variable staying power. Blog, which was ten years old when Merriam-Webster crowned it in 2004 (while app may be old enough to vote), isn’t going anywhere, nor is podcast. But eventually, many once popular terms evoke nothing more than a chuckle (â€Å"floppy disk,† anyone?). And to w00t, I say, â€Å"W00t-ever.† Jargon from economic and political contexts serves as a shorthand, but Steven Colbert’s brilliant-in-its-time truthiness is as stale as Bush-speak jokes (or perhaps I misunderestimate it), and â€Å"weapons of mass destruction† and embedded have acquired a derisive connotation their coiners did not intend. Variance in American English and British English is also an obstacle: Several of the Oxford Dictionaries selections are obscure to US readers. (â€Å"Big society† refers to localism in government, bovvered is part of a British TV character’s dismissive catchphrase â€Å"Am I bovvered?† and chav refers to a lumpen-prole UK subculture with a perplexing penchant for faux-Burberry plaid couture.) Environmentally oriented terms at least the ones in these lists seem to have legs: We’re still discussing sustainability and footprints (as in â€Å"carbon footprint†), though perhaps without the fresh vigor applied just a few years before. A couple of these lists offer a word of the year for 2011 (the other listmakers have not yet weighed in for the current year), but you are also entitled to your opinion. Which word (or phrase) do you nominate for the honor? Want to improve your English in five minutes a day? Get a subscription and start receiving our writing tips and exercises daily! Keep learning! Browse the General category, check our popular posts, or choose a related post below:50 Idioms About TalkingHomogeneous vs. Heterogeneous10 Varieties of Syntax to Improve Your Writing