201
votes
Accepted
Nudism in space: Why wear clothes anyway?
Clothes require laundry because they have accumulated dirt and other materials from the environment and their wearer. If the astronaut was not wearing those clothes then that material they captured ...
- 6,213
87
votes
Nudism in space: Why wear clothes anyway?
Clothing performs essential duties on the station in addition to modesty. They are an easy way to organize stuff. In addition to pockets, clothing is festooned with velcro strips for attaching tools, ...
- 128k
26
votes
Nudism in space: Why wear clothes anyway?
In addition to capture of contaminants, such as dead skin, hair, sweat, etc, and abrasion/cut protection, clothing forms a basic thermal layer that allows the human body to better regulate its ...
- 1,103
18
votes
Nudism in space: Why wear clothes anyway?
A picture might be worth a thousand words. Just imagine this situation without clothes:
- 1,788
10
votes
Accepted
How much algae would you need to fully support a person?
I was recently involved in a feasibility study for using Chlorella vulgaris algae for generating medical oxygen using solar energy in off-grid medical facilities.
Bottom line: it requires one cubic ...
- 24.8k
8
votes
Accepted
What will J002E3 be like on its return?
We don't know exactly what kind of shape it will be in. There are a few similar objects that have been returned, however, that we can get at least an idea of what it might look like. Let's look at the ...
- 122k
8
votes
Accepted
How long could the shuttle remain docked to ISS and still capable of landing?
Shuttle mission length was limited by lots of consumables, including propellant and canisters for the life support system.
The Station-to-Shuttle Power Transfer System (SSPTS) could provide electrical ...
- 128k
6
votes
Accepted
Which is the longest distance traveled by a space craft?
The spacecraft farthest away from Earth is Voyager 1. But that's not necessarily the longest distance traveled. If you accept the distance traveled while in orbit, a spacecraft can rack up a lot of ...
- 128k
5
votes
Accepted
Is retired astronaut Scott Kelly now the same height as his brother?
Mark Kelly, told CNN's "Erin Burnett OutFront" by email, Scott Kelly's life, height return to normal after near year in space, that his brother is back to his normal height.
Astronaut Scott ...
- 6,999
5
votes
Accepted
Ion thrusters trip time
The first thing to say is that neither a nuclear powered ion rocket, nor a nuclear pulse rocket such as Orion is capable of sustaining 1g continuous acceleration over lightyears (nor indeed is any ...
- 19.6k
4
votes
How long could the shuttle remain docked to ISS and still capable of landing?
When Shuttle was docked, it was used to do any propulsive maneuvers the station required. So, eventually you would use up enough prop to hit the propellant quantity redlines for a safe deorbit. You ...
- 187k
4
votes
Why have we not seen spin gravity testing in space? Artificial gravity created through centrifugal/centripetal force
Even small, relatively cheap steps haven't been taken to space
Leaving aside the idea that there's such a thing as "cheap" in space: Sept. 14, 1966 - Gemini XI Artificial Gravity Experiment
...
- 8,188
3
votes
Cryogenic storage in Starship header tanks
Per his 2017 Reddit AMA:
The main tanks will be vented to vacuum, the outside of the ship is well insulated (primarily for reentry heating) and the nose of the ship will be pointed mostly towards the ...
- 10.8k
3
votes
What is the optimal selection for a small self sustaining space farm?
Allow me to try and describe to you the magnitude of this question
The crux science here isn't necessarily genetic engineering, it's ecological engineering with a comprehensive understanding of ...
- 1,020
3
votes
Nudism in space: Why wear clothes anyway?
I think the most important reason is that clothes perform a very important social function. Most of our workplaces are climate controlled and yet we still wear clothes indoors, putting considerable ...
- 11.4k
2
votes
Accepted
Shape Memory Metal Self Stablizing Solar Sail
Shape memory allows generally only change shape once during a heating cycle and need external force to deform them. The much older bimetallic structures or wax motors would probably work better for ...
- 23.4k
2
votes
Ion thrusters trip time
The accepted answer nicely addresses the impossibility of accelerating at one g for years, regardless of fuel source / thruster type. This answer pokes deeper at the concept of a nuclear powered ion ...
- 75.5k
2
votes
Cryogenic storage in Starship header tanks
The CH4 header is a pimple on the bottom of the common dome. That is, there is a single shared dome between the upper tank (CH4) and lower tank (LOX).
The LOX header is in the very tip of the nose (...
- 80.2k
1
vote
How long can the dawn probe‘s ion thrusters burn?
Never mind, it‘s 51,385 hours (wow!)
From NASA's Dawn by the Numbers:
Source: NASA/Jet Propulsion Laboratory-Caltech
Published: November 15, 2018
NASA's Dawn mission by the numbers:
51,385 hours of ...
- 121
1
vote
Accepted
Effective range of a laser propelled solar sail
How far could we effectively propel the craft?
For space travel, "how far" isn't a very good question to determine the difficulty of space travel. Instead, a much better metric is the delta-v, or ...
- 336
1
vote
Muscle loss in space
Could astronauts maintain muscle mass by playing a game in a viscous fluid - probably but it would depend on the game.
The loss of muscle mass is due to the muscles not being used as frequently and/...
- 266
1
vote
Why not leave interplanetary probes on standby after primary mission, activating them at will decades later?
The primary issue is that most missions, such as Cassini, are not particularly useful once consumables such as propellant or RTG lifetime run out. Adding consumables that enable use after the mission ...
- 987
1
vote
Would a biological resource-system be feasible for long-term manned flights?
On one hand, a biological resource system should be avoided because they are large and energy intensive. On the other hand, it is likely necessary due to the complex biochemical requirements of humans....
- 24.8k
Only top scored, non community-wiki answers of a minimum length are eligible