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46

It did, with the third rocket stage. Instead of just becoming another object in solar orbit like the previous Apollo third stages, this time the third stage was sent into the Moon for a crash landing whose impact would be recorded on the seismometer installed by Apollo 12. This test went off without a hitch and successfully returned data from the ...


40

According to the link here, In meteorological rockets, the temperature sensor is not measured as the rocket ascends but a payload containing the sensor is ejected from a high altitude and as it parachutes down measurements are beamed back.


35

To start with a summary: (1) the extra delta-V needed to halve the journey time is not as much as you think and (2) the SpaceX mission plan is, effectively, a really, really huge launch from Earth. To expand on the first point, we need to look a bit more closely at how interplanetary travel actually works. There are lots of discussions on stack exchange (...


30

In addition to crashing the Saturn V's S-IVB into the moon to collect seismic data from sensors installed by the crews of Apollo 11 and 12, several life sciences experiments were performed on the crew before and after Apollo 13. While all of the inflight experiments were canceled, researchers still managed to collect data on the cardiovascular's response to ...


27

Watney did have trouble controlling himself with the "iron man" suit puncture trick; it's plausible that he could quickly get the hang of positioning his hand to thrust through his center of mass (though that all happened fast enough that I didn't see if it was so depicted). Mastering that technique in the few seconds he had available was pretty unlikely, ...


25

The most inaccurate "artistic license" thing was the Martian storm - Andy Weir admitted that he misrepresented it for dramatic effect. The most blatant error though was in growing the potatoes. In particular, the matter of lighting. For the depicted indoor growth, Mark would need 60 kilowatt worth of LED growth lights, and a proportionally sized solar farm. ...


22

Excellent question! That's probably ground velocity or more likely velocity in an ECEF (earth-centered, earth-fixed), also known as ECR (earth-centered rotational) frame that they are displaying, referenced to the rotating frame of the Earth. A hint would be that it is zero before lift-off even though the Earth is rotating. Wikipedia gives the value of $3....


16

The most obvious thing in my opinion was the orientation of Hermes in the scene right before they receive the hidden transmission with instructions for the Rich Purnell manoeuvre. They had just discussed the fact that Hermes is currently slowing down in its approach to Earth, which would mean the vehicle is pointing retrograde. However, when it cuts to ...


15

Suborbital sounding rockets cost about 1/100 as much as an orbital launcher. Black Brant XII, one of the most advanced sounding rockets in use, can take 100-400kg payload into space for \$600K. For a Falcon-9-based sounding rocket approach to make any sense, you'd have to describe a single payload that delivered as much science as 100 individual 100kg ...


15

The Voyager probes are currently further away from earth than any object before. Knowing their position alone gives interesting scientific data, because it tells us their speed and direction, which gives us information about the forces which act on objects so far outside of the solar system (microgravity, acceleration through solar winds, friction with ...


13

Here are some Apollo specific innovations: microchip, cordless tools, joystick, CAT scans, technology in MRI machines, modern shoe designs, freeze dried food, vacuum sealed packages, dampening material, retro-reflector (detects chemical leaks), water purification, silicon based storage of records, fly-by-wire, ground water cleaning, large fabric roofs used ...


12

Here is an answer from over on aviation.stackexchange.com which addresses this issue. I've quoted a portion of it below, but see that link for more info. As you measure temperature moving at high velocities, your outside thermometer will measure a higher temp than what is actually outside (what a non-moving thermometer would get). That's because as ...


8

The two Voyager spacecraft are now conducting the Voyager Interstellar Mission: The mission objective of the Voyager Interstellar Mission (VIM) is to extend the NASA exploration of the solar system beyond the neighborhood of the outer planets to the outer limits of the Sun's sphere of influence, and possibly beyond. This extended mission is ...


7

NASA actually have looked into mining the gas giants, http://mdcampbell.com/TM-2006-214122AtmosphericMining.pdf, this paper outlines some the methods they might use, whether they will or not is a different question. They were considering mining methods, of Uranus due to its relatively low wind speeds (compared to Jupiter, Saturn and Neptune, such as ...


6

Combustion analysis computer programs and specifically exact reacting gas chemical kinetics programs were developed on the Apollo program to analyze and optimize rocket nozzle designs for efficiency improvements. Adaptation of these programs to other than rocket fuels provided the ability to analyze the mechanisms of NOx formation in fuel/air combustion ...


6

There are studies into mining in space, but not for the gas giants. The outer planets are massive. Very massive. This means they have very big gravity wells. Lifting anything from Jupiter is going to be extremely energy-intensive, getting it back from Jupiter to Earth is too. So, currently, this is the realm of science-fiction. As for the second part ...


6

Exactly at the center-of-mass of the Earth there is no net gravitational force. Gravity comes from mass, and all the mass of the Earth is evenly distributed around the center-of-mass (by definition), so all the forces cancel out. As you get deeper and deeper, the net gravitational force falls -- linearly if density is constant. In practice, of course, you ...


6

The important thing to note here is that to say "it takes 8-9 years" doesn't make sense without specifying who it applies to. When relativistic effects start to apply, it's not the same in all reference frames. Let's take your Proxima Centauri example. At half the speed of light, the spacecraft reaches Proxima Centauri in 8.5 years, and if it immediately ...


5

With 2 mm/s^2 acceleration, Hermes' 124 day trip from Low Earth Orbit to Low Mars Orbit is impossible. "Low earth orbit?" a Weir defender might object, "It's all hyperbolic fly bys." Which is wrong, of course. The hyperbolic rendezvous were extraordinary maneuvers made under unusual circumstances (Watney needing rescue). The 124 day earth to Mars trip ...


5

In this answer, I'm going to assume the tunnel is a perfect vacuum and there's no intense heat or pressure. This is a thought experiment. If you and John fall at the same time, you guys will meet approximately 20 minutes after you jump into the tunnel. Depending on how wide the tunnel is, you guys will most likely collide at a velocity of around 11 km/s. ...


4

I know that it has been theorized about harvesting isotopes of Helium or Hydrogen space, including studies for / by NASA. In fact, NASA did study mining celestial bodies, including other planets, and still does. The study report "Space Resources" (NASA SP-509, 1992) has become a classic. It can be found here http://www.nss.org/settlement/spaceresources/...


4

Advancement in science comes from repeated (and repeatable) observations that are systematically processed, hypotheses that get tested on experimental data, and conclusions that get peer review. One high-altitude balloon with low-cost off-the-shelf sensor payload will add nothing to existing space/earth sciences if you do not do the following: read ...


4

Without its main thruster, orbit maneuver engine (OME), that's been completely dismissed as possible to restart (they did try but only got a small fraction of thrust out of it, about 10%) and have even dumped oxidizer (Mixed Oxides of Nitrogen, or MON) to save on spacecraft's mass as reaction control system (RCS) thrusters don't need it, extremely low (300 ...


4

As time goes by, the technological backbone of any system becomes dated and outmoded. For example, several of the space shuttle systems were still using items designed in the Apollo days. These can be refit to use newer technology (i.e. using laptops to supplement shuttle computers, new glass cockpit technology, etc.), but there always comes a point where ...


4

No evidence for identifiable scientific product(s) later used by the ISS and/or other manned spaceflight. However, researchers of biosphere two found the original crew's lowered blood pressure, blood cholesterol, and enhancement of there immune systems to be caused by Roy Walford's low calorie restriction diet (Walford, R., Mock D, Verdery R, MacCallum T, ...


4

One addition that I struggle with was the rapid way he was able to use poop and Martian regolith to create soil to grow the potatoes. In the book at least (didn't see the movie). I can't anywhere find data on how long it takes to make organic soil for plants; sure hydroponics are great, but that's not what Mr. Whatney did. Soil takes a long time to create ...


4

I think it's just barely possible that 1850s technology could achieve a crewed suborbital launch above the Kármán line, similar to the first crewed Mercury missions, but that anything beyond that would not be possible. Without modern rocket engines, the best propulsion option is a black powder rocket. This has a specific impulse of about 80 seconds (a ...


3

I liked the film and found it quite realistic overall, but what I found very unrealistic was his repair of the hab using plastic foil and duct tape. It has already been mentioned that the martian atmosphere is very thin. Inside the hab the air is breathable, so it's pressure must be substantially higher than that of the martian atmosphere. If the pressure ...


3

I've been searching around, and found some piecemealed data. Here's what I can find. Some very limited data is available from the Planetary Data Archives, mostly in the form of cooperative missions with NASA I found some data on this website, from the Space Research Institute Some of it appears to be hosted on a private network similar to the WW2, known as ...


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