Andy
  • Member for 6 years, 10 months
  • Last seen more than 5 years ago
Drone Racing on moon
6 votes

Small automated flying probes have been considered for the exploration of lunar lava tubes. From Flying, Hopping Pit-Bots for Cave and Lava Tube Exploration on the Moon and Mars. by J. ...

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Platinum Colloid in Liquid Hydrogen fuel to increase fuel efficiency
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20 votes

Short answer: no, it won't increase the performance of the rocket. Platinum (or other catalysts) can be used in fuel cells, where the purpose is to get a chemical reaction at (relatively) lower ...

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How serious a problem can outgassing of satellites be?
13 votes

There are a few recorded incidents of spacecraft contamination caused by outgassing. On Cassini, some haze was noted in test photographs after launch; this was thought to be due to some outgassing ...

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Who is the space artist? Patterns on the Spheres robots on the ISS
12 votes

These are some of the SPHERES satellites. They're little flying robots, driven by pressurised gas, intended to fly around inside the station. They were created for various indoor experiments, such as ...

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Is stellar photosphere aerocapture possible, and if so, is it a viable option for rapid deceleration from relativistic speeds?
3 votes

At 0.1c any gas colliding with the craft's heat shield would probably undergo nuclear fusion... which would make heating effects far worse than the usual "friction" (compression) considerations. So I'...

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How was it possible for the Apollo 11 to film and take pictures with such radiation?
22 votes

Radiation can affect film - but bear in mind the radiation around Chernobyl was, truly, extremely high. The radiation in our region of space is not as extreme. Also bear in mind that the earlier ...

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When can we (public) expect to see the first optical images of Jupiter from the Juno spacecraft?
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11 votes

There's an interesting Planetary Society article about this: What to expect from Junocam We won't be able to see spectacular views of Jupiter's belts and zones from Jupiter orbit until the very end ...

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Dragon 2 Propellant Capacity
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9 votes

That's 1,388 kg of propellant for the whole vehicle, not per engine. Reading the original document referred to by Wikipedia, it says 3,060 pounds of propellant for the Crew Dragon capsule. (It's on ...

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Could an ISS astronaut photograph something like this 1km "Van Gogh" if they knew it was there?
4 votes

Loosely on the theme of art photographed from space: A set of temporary floating piers have recently been set up on Lake Iseo, Italy as a piece of interactive art. An animated picture from the ...

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In what way is artificial gravity expected to avoid/reduce bone loss?
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5 votes

Just a partial answer, limited to this part of the question: Does each bone need to experience strain separately - is it localized, or is it more systemic. Bone growth is definitely controlled ...

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How is long-distance optical communications coming along in space?
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6 votes

The European Data Relay System has recently begun testing. It's for getting data from Earth orbiting satellites down to the ground quickly, without waiting for the satellite to pass over a base ...

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Is there software that allows me to experiment with solar sail parameters?
4 votes

Martin Schweiger's "Orbiter" (a freely downloadable simulation/game) has basic radiation pressure simulation and apparently a solar sail scenario which would be the first thing to try. (I haven't ...

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What would be the (most difficult) challenge to make a 10,000 year satellite?
15 votes

The biggest challenges are going to be what people have already mentioned - the funding (don't skirt over that comment, you did ask for the challenges), an energy source for 10,000 years, and how to ...

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Good source for launch videos
0 votes

The Internet Archive has a lot of older public domain NASA material. For example: footage from the Apollo 16mm launch cameras for various launches, all rolled into one very long slow-motion movie. ...

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Data for Moons in the Solar System with Masses
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4 votes

JPL have a Solar System Dynamics site that looks like it has useful information. The Satellite physical parameters page has useful information, though note there isn't a raw mass. Instead it gives a ...

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What are the top temperatures occurring during reentry?
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18 votes

The Stardust sample return probe had an interesting re-entry to Earth's atmosphere. Returning from a solar orbit the maximum deceleration has been reported as 34g. Maximum temperatures are estimated ...

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What are these structures on the Lunar Ranging Retro Reflector (LRRR) arrays for?
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8 votes

The Apollo 11 EASEP handbook gives basic information on the first version. Of the LRRR, it has just two pages of text... There are some (poorly reproduced) images labelling the main parts. It's ...

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How will Yuri Milner and Stephen Hawking's nanobots decelerate and transmit data upon arrival at Alpha Centauri?
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6 votes

There seems to be very little published information at this stage. There is a main page that has been set up for the initiative (Yuri Milner's Breakthrough Foundation). The most interesting bits ...

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What's the baseball bat for? (seen in CRS-8 berthing NASA TV broadcast)
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57 votes

The baseball bat is for "Attitude adjustment", apparently :) Source: Arstechnica photos of ISS control room (ADCO=Attitude Determination and Control officer) Here's a better pic of the bat from the ...

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What is the launch profile for interplanetary missions typically like?
1 votes

Most interplanetary flights are put into a parking orbit first, not "straight up" direct ascents. In any case, assuming a low energy Hohmann transfer is required, you'd want to depart Earth's orbit ...

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Why is comet deflection so hard (and how does a fusion rocket help)?
6 votes

Assuming that our vaporization is at least as effective as a rocket engine (ISP 500) that gives 2.5m/s delta v Unlikely - the rocket engine uses a shaped engine bell tuned to give the best thrust (...

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Why did the Zond 5 tortoises lose body mass so quickly?
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9 votes

It's important to note that the tortoises carried on the Zond flight were probably not given any food or water, and I suspect they were selected because they could survive that for a long period. So ...

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Is there an optimal launch inclination for interplanetary launches?
4 votes

I would say, anywhere where the line of the ecliptic is directly overhead. In other words, anywhere between the line of the Tropics (with two launch windows per day), so your suggestion of near the ...

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How (and when) do astronauts suit up when leaving ISS?
2 votes

There's an interesting blog entry describing the return to Earth for an earlier expedition. Here's a quote from the most relevant part: Gennady, Andreas and Aidyn will put on medical telemetry ...

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Detecting a Nuclear powered vehicle from outer space (at least 8 AU or further out) feasible?
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8 votes

I sometime see this quote in forum arguments against "Klingon/Romulan-style" cloaking in video games that tries to be close as possible to real-life I gather the "World Building" Stack exchange might ...

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Could fuel be "hosed" (pumped) from the ground to a launcher?
6 votes

The simple solution is to launch from much higher up. Either an air launched rocket or launch from a raised platform. (Both have been described, and one has been used.) Or just begin the launch ...

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How precise are our Mars landings?
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12 votes

Curiosity was targeted at a small area later named Bradbury Landing and came down 2.4 km from the centre. See also: landing ellipse comparison (earlier probes were of much lower accuracy.) Of course,...

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How long can a LEO Satellite maintain its orbit if it loses all power?
5 votes

It depends entirely on the orbit and the "aerodynamic" properties of the satellite. For example, the ISS is often quoted as descending between 70 to 100 metres per day and needs frequent boosts. (As ...

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Has any other term been used for a solar day on a solar system body besides "sol" on Mars?
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4 votes

"Lunation" is informally used as a "calendar" for lunar days. However I'm not sure it can be said to be an equivalent of "sol" because it's more properly known as the lunation number. So probably the ...

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Why did the Apollo Lunar Module have four landing legs?
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24 votes

There is some interesting information here. Three legs were probably not robust enough, they do not appear to have been considered seriously for any length of time. Five fixed legs was the main ...

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