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54

In order to properly assess this, you need to take a few things into account: What are the typical exposure levels? How would Solar Storms be protected against? What kind of shielding do you need? Much of my answer to this was taken with help from The Case for Mars, by Robert Zubrin. First of all, let's start with the long term limits. As a starting point,...


54

Eyes do strange things in microgravity (when you consider they're deformable bags of fluid, this isn't too surprising). This report outlines the changes that can be identified after just a short parabolic flight. Eye test charts provide a way to investigate this without requiring heavy equipment or specialists. This study appears to be an on-going project ...


37

NASA has been studying the effects of microgravity on astronauts' eyes for at least a few years. This article from Space.com from 2012 talks about some of the findings from that time. In a new study, researchers used magnetic resonance imaging (MRI) to study the eyes and brains of 27 astronauts who spent an average of 108 days in space aboard NASA's ...


34

NASA, ESA, and RSA follow very conservative policies towards sending a potentially infected person into space. All the blood tests and other screenings in the days, weeks, and months leading up to a launch would make it virtually impossible for an astronaut to carry a communicable disease up to the ISS without showing symptoms or being detected as an ...


30

From this question on Physics.SE: But other than that, there is no reason why a man couldn't be lobbed from behind Jupiter, make a slow-down loop around the Moon, then spiral down to Earth... given some marvelous suit that will withstand the atmospheric entry. From this question on Felix Baumgartner: Note that even if he jumped from "infinity", he ...


26

The test kit is there in case a female crewmember suspects that she might be pregnant. Your second question will never be answered because of US medical privacy laws. For the 3rd question, I have not found a documented answer, but I suspect a medical evacuation would be in order, due to the unknown developmental effects on the unborn child. This would ...


23

For NASA, candidates must be able to pass the long-duration space flight physical. Height, blood pressure, and vision are three of the physical requirements included in this test. From their website: Astronaut Requirements Pilots Distant visual acuity: 20/100 or better uncorrected, correctable to 20/20 each eye. Blood pressure: 140/90 measured in a ...


21

Based on saturation diving operations, it looks like the limits are as follows: Compressed air: Nitrogen narcosis limits you to around four times Earth's atmospheric pressure. Any gas mix: Hydreliox was used for the current depth record; insomnia and fatigue issues appear to limit you to around 65 times Earth's pressure regardless of gas mix. Neither Titan ...


18

The US's only "modern, real" space suit, the Extravehicular Mobility Unit (EMU), was designed in the 1970s. It has a very limited sensor suite and no automation at all. The only sensors used in the suit are A biomedical harness (with electrocardiograph electrodes) A carbon dioxide (CO2) partial pressure sensor A total pressure sensor ventilation flow ...


17

While Rory's answer is close, let me give a few additional details. The orbital speed is about 7.8 km/s in low Earth Orbit. If you are orbiting, you will not fall straight down. It just won't happen. In fact, the maximum speed would result from a minimal burn, which would take you through the atmosphere quite slowly. You will start slowing down to an extent ...


13

Sure. Why not. You'll want some sort of heatshield of course. Or this more practical design: Or this earlier, less convincing concept: It looks like the fall from a $100\,km$ tower is survivable in terms of G's. I assumed a $100\,kg$ person and a $2\,m$, $100\,kg$ heatshield and other equipment. Assuming a blunt body $C_D$, I get a ballistic ...


13

Yes medicines are carried on all space flights. The astronauts will communicate with doctors in the ground station, and doctors will monitor the astronauts periodically. HEADACHE Mercury crews carried nothing for pain, Gemini missions carried Aspirin and injectable Demerol, and Apollo added Tylenol and Darvon BACKPAIN The astronauts are ...


13

There have been no known long-term positive health effects reported. Then again, euphoria and elation are considered negative health effects, and both have been reported, and many other causes are used as recreational stress relief. Almost all astronauts report positive mental attitude changes from their time in orbit. This isn't exactly measurable, tho', ...


12

Vacuum on the skin will not normally cause blood to flow through the skin. It can cause the skin to distend (push outward) from the fluid pressure behind it, and to stretch the capillaries under the skin. Actual vacuum exposures have shown that even 20-30 minutes of exposure do not result in external bleeding - but they do result in massive bruising. Joseph ...


12

Yes, astronauts do use their legs. In weightlessness, any movement you make (even tiny things like pressing a button) will push you in the opposite direction. At many workstations, footholds are provided. The astronauts use the footholds to hold themselves in place, so they can use both hands for the work they're doing instead of continually needing one ...


11

Yes, shared by MichaelT in The Pod Bay just recently: 2015/16 ICD-10-CM Diagnosis Code V95.43: Spacecraft collision injuring occupant There are others that you can search for by keywords on ICD10Data.com, for example: 2015/16 ICD-10-CM Diagnosis Code X52: Prolonged stay in weightless environment 2015/16 ICD-10-CM Diagnosis Code T75.81XA: Effects of ...


11

Can the vacuum of space be used to sterilize equipment? Supposing that washing dishes and sterilizing medical equipment could be expensive to do in space, would a viable option be to expose dishes, scalpels, silverwear etc to the vacuum of space? Would the combination of "vacuum" and radiation from the sun be enough to kill enough of the bacteria and ...


10

The Roscosmos requirements for the professional cosmonaut candidates are published here. The google translation seems to be intelligible. It includes the list of medical areas of inspection: internal organs inspection; neuropsychiatric inspection; surgical inspection; ophthalmological inspection; otorhinolaryngologic inspection; dental ...


10

Other then decay caused on earth by bacteria and such, other factors for decay in space; where decay = loss of pristine mummification of the original freeze dried corpse. A body in orbit around a sun would be impacted by the solar radiation. A quick search only found research on live tissue. Presumably this would cause some denigration of the mummified ...


10

It would seem that the ultra-cold vacuum would kill off most of the bacteria, etc in the body, as well as quickly boil off all of the water content. Here's a lovely description of the process from Focus magazine: In space we can assume that there would be no external organisms such as insects and fungi to break down the body, but we still carry plenty of ...


10

If I'm reading the question correctly, this is a question about how difficult the engineering challenges are. Given the data in the question itself(amazingly helpful) the real question is keeping the person you're dropping from being crushed/catching fire. I believe the density of air and the spirit of the question prevents effective parachuting at high ...


10

Science Fiction has shown several interesting possibilities for surviving the reentry, most notably, either a suit that's got a high thermal load, or an ablative shield that one rides down. Science fact has an even more interesting possibility: the shuttlecock mode. Inspired by a badminton shuttlecock, Scaled Composites uses it as the reentry mode for the ...


10

Dr. Tore Straume of NASA's BioSciences Division actually published a paper on this very topic. Titled: "Radiation Hazards and the Colonization of Mars: Brain, Body, Pregnancy, In-Utero Development, Cardio, Cancer, Degeneration" The study conducted by them concluded that the Space radiation negatively affects Male fertility. The Cosmic Radiation during ...


10

The Canadian Space Agency (CSA) was helpful on Twitter (@csa_asc in English and @asc_csa in French language) and answered a couple of my questions. This is in response to a general question in the title: Me: How do astronauts battle loss in blood volume in microgravity? CSA: Astronauts typically combat the effects by wearing compression garments ...


10

The Med.Ops section of the ISS User's Guide is apparently available online. It is generally split into the following sections Crew Health Procedures Routine Non-emergency procedures Emergency procedures I'm far from being a medic, or even para-medic so my take may be wrong. A quick gander at the sections on Nosebleeds, and Penetration of the Eye by a ...


10

First, I want to get out of the way that the equivalence principle, which is well supported by experiment, contends that gravity and acceleration are one in the same: "pseudo"-gravity caused by acceleration is equivalent to "real" gravity. So, there is no physical difference between walking in a spacecraft accelerating at 9.81 m/s2 and walking on the surface ...


9

I am aware of one such scientific program that spun off something useful: the Salmonella vaccine research by Arizona State University. The virulence of the Salmonella bacteria was altered in microgravity environment, generally making it more aggressive. These changes in bacteria behavior helped identify new possibilities for vaccine development. The research ...


9

In the early days of crewed space exploration, size and weight of crew was an issue. The original batch of Soviet cosmonauts selected were restricted to 1.75m height and 72kg mass, for example, and US astronauts to 1.80m and 82kg. As launchers got bigger and spacecraft got more complex (and roomier), these restrictions became less important because the ...


9

Yes, it was performed during Gemini 5 and 7. Here's the report. ... Ground observation sites were provided on the Gates Ranch, 40 miles north of Laredo, Texas, and on the Woodleigh Ranch, 90 miles south of Carnarvon, Australia. At the Texas site, 12 squares of plowed, graded and raked soil 2000 by 2000 feet were arranged in a matrix of 4 squares deep and ...


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