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Where is the TEA-TEB stored for the Merlin engines onboard Falcon 9?

The Merlin 1D engines can restart up to four times, they use the pyrophoric mixture of TEA-TEB (Triethylaluminum-Triethylborane) to ignite the engines. My question is where is this stored in the ...
19
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0answers
226 views

What is the current location of Link-built Apollo Mission Simulators?

There seems to be confusion about the final disposition of, and even the number of, Apollo Mission Simulators built by Link Flight Simulation Division. This question is not about any simulator built ...
17
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0answers
675 views

Does the FAA still license the people who fold human-rated reentry parachutes?

One of the links in the question International Orange? is the History.com article The Amazing Handmade Tech That Powered Apollo 11’s Moon Voyage which says of Apollo capsule re-entry and landing ...
17
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348 views

Was Jules Verne the first to propose the retro-rocket concept?

In his novels 'From the Earth to the Moon', and 'Around the Moon', Jules Verne writes about a set of rockets fitted to the spacecraft he imagined, that were intended to be fired in order to slow down ...
13
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125 views

Why did SpaceX swap the LOX and CH4 tanks between Mk1 and SN1?

According to most sources, the Starship Mk.1 had its LOX main tank (not talking about the header tanks here) on top and its main methane tank below. But it seems the SN1 revision, and all subsequent ...
13
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188 views

What were the Top 10 Shuttle Risks in John Young's “famous letter”?

Whilst reading A Technical History of the External Tank I ran across this comment: Although the problem has not recurred, John Young, in his famous top ten Shuttle risk letter ...
13
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299 views

How did “the kid” (John Meisenheimer) calculate that there was a wave in the jet stream and Explorer 1 would be okay to launch?

The tough but timely question NASA at sIxty years, will there be a new moonshot mandate? links to the NASA YouTube video NASA 60th: How It All Began which shows a lot of really nice, historical file ...
11
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184 views

Have there ever been any incidents where something valuable was unintentionally throw out with the trash?

In "What do astronauts do with their trash on the ISS?", a commentator asked the title question and was encouraged to make it a new question, but apparently never did. The linked question is ...
11
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157 views

How does increased environmental radiation affect medication potency, long and short term?

The issue of the effects of radiation on medication potency is not only important for long term stays in the ISS, but also very important for longer duration journeys and even for colonization. One ...
10
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120 views

What is this device/object that the SpaceX astronauts are holding?

Watching the SpaceX Demo-2 launch preparation livestream, I saw both Bob and Doug using some sort of little gadget. It looks like a chunky cell phone, or a flat gopro. It appears to have an LCD on the ...
10
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92 views

Why did GRACE mission have launch window?

GRACE mission which was launched on March 17th, 2002 had a 10 minutes launch window. The mission was to launch a couple of earth observation satellites. And interestingly, NASA's GRACE Launch Press ...
10
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416 views

How are the Voyagers' thrusters configured in a novel way to minimize accelerations along Earth-spacecraft axis?

I've just read in Eshleman et al 1977 Radio Science Investigations with Voyager that the voyagers have: ...a novel attitude-control thruster configuration that minimizes accelerations along the ...
10
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122 views

Is loss of flexibility a concern with crew on the ISS?

Videos of people on the ISS make it clear how little they need to bend or stretch, and how their joints stay in their neutral position most of the time as they float around - elbows, knees and hips ...
9
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91 views

Does Crew Dragon have a quick-release hatch?

After today's Crew Dragon launch was scrubbed, it took the pad ninjas at least ten minutes to open the hatch. One of the major criticisms of the Apollo Block 1 hatch design after the Apollo 1 fire ...
9
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121 views

Small display manipulation unit in SpaceX Crew Dragon

In the historical SpaceX Demo-2 mission there's a moment when Douglas G. Hurley takes out from the souti's leg bag a small gadget and immediately drops it: SpaceX support staff helps and puts the ...
9
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97 views

Why does the Starship methane header tank have so many holes in it?

This picture from Elon shows us the methane header tank positioned inside the main tank. I understand that one of the reasons for header tanks is to keep them pressurized when the main tanks do not ...
9
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135 views

Do Starlink satellites have cameras?

Obviously, Starlink satellites are equipped with sensors for attitude and location detection (like a star tracker or sun tracker) but I'm wondering if they have with any direct Earth observation ...
9
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318 views

What went wrong with Apollo 15 astronaut Al Worden's seat when he was all alone, circularizing?

The X article NASA shock: Apollo 15 astronaut's Moon landing confession - 'Can't do anything to me now' says "NASA astronaut Alfred "Al" Worden dropped an astonishing Apollo 15 confession, claiming ...
9
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198 views

What is the utility of this peanut-shaped ground facility?

The following image is from GSLV-F11 GSAT-7A Mission: Location: Second Launch Pad (SLP), Satish Dhawan Space Centre, Sriharikota, India. Please click here in case you want to see the image in ISRO's ...
9
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118 views

Detailed information about the Soyuz descent module connection box?

Anyone have some detailed information about how all this connectors, located in the soyuz descent module? Are they used only when they setup the Soyuz or they are ...
9
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141 views

What rocket uses the largest percentage of Fuel/Oxidizer before liftoff?

inspired by this question: How much propellant is used up until liftoff? which asks how much propellant (fuel/oxidizer) a typical rocket uses before liftoff. What has been or is the most non-typical ...
9
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75 views

What science data has been released from Chang'e 4?

Chang'e 4 was the first soft landing on the far side of the moon. What science data has been released from it? That is, in two parts: what science was done and of that, what data has been released to ...
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911 views

Which launch was the first to use a dogleg maneuver?

Jake Blocker's excellent answer explains what a dogleg maneuver is, what it's for, what it looks like, and even what a real dog's leg looks like for comparison! A dogleg maneuver is done to change ...
9
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418 views

Why was the Apollo 6 service module painted white?

All other SM's were silver except Apollo 6. I'm wondering what the justification for this was, if any?
9
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366 views

How do domes in lunar impact melts develop, and might they be hollow?

On the floors of young craters of the Moon, smoothly rounded domes are visible in some spots. Lalande crater has 4 of them, each around 200 m across. Here are less regular ones on the floor of ...
8
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103 views

What is inside the overhead compartments in crew dragon

During the DEMO-2 live stream there was a black section visible above the heads of the astronauts. In an image tweeted out by Elon these were labeled as “9” and “10” with symbols of water droplets. ...
8
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113 views

What programs did David Scott add to the Apollo computer for Apollo 15?

David Scott was the commander for Apollo 15. He was also a main point of contact between MIT, who developed the Apollo flight computer, and the astronauts who were going to use that computer. ...
8
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135 views

How long could the ISS function if removed from Earth orbit?

Suppose the ISS were instantaneously moved to the opposite side of the Sun from Earth - how long would it continue to function? Are there any systems aboard that depend on passing behind the planet ...
8
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182 views

What is the heaviest part of a rocket engine?

I'm trying to understand how much different parts of a rocket engine weigh. For example, according to Wikipedia, Merlin engine weighs 470 kg, of which 70 kg is the turbopump. How is the remaining 400 ...
8
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116 views

Were there any launch vehicles with so heavily pronounced Plume Induced Flow Separation (PIFS), other than Saturn V?

This answer describes a very interesting phenomenon of Plume Induced Flow Separation on Saturn V vehicle. (Apollo-6 S68-29737 photo, courtesy NASA) This is, basically, when "fire" from engine ...
8
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154 views

Project Mercury capsule switch orientation

I noticed that the majority of the toggle switches in the Mercury capsules move in a left-to-right manner. This seems unusual to me, since Gemini, Apollo and the Shuttle all predominantly use up-down ...
8
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152 views

Is the vestibular system ever useful in spaceflight?

The Vintage Space video Eleven Deaf Men Helped NASA Leave Earth describes a number of different NASA experiments done on human subjects who had damaged vestibular systems due to childhood illness. ...
8
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155 views

Does the kinetic impact of gas particles cause erosion to the surface of objects in orbit?

When satellites or space stations orbit the Earth, they are constantly experiencing a low level of aerodynamic drag from Earth's atmosphere. The ISS needs to be reboosted every few months to account ...
8
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198 views

Was this the first-ever photo of a full moon very close to lunar new year?

Limiting the concept of "lunar new year" to "Chinese New Year" (since there are many lunar and lunisolar calendars, the latter of which the traditional Chinese one is a widely used example), is this ...
8
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187 views

Are the ejected first stage Electron rocket batteries really incinerated?

This answer reminded me that the Electron rocket drops one of it's batteries when it is mostly spent. We might call that "micro-staging". This answer quotes Spaceflight 101: With a low auto-...
8
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259 views

What spinoff technologies have come from the Soviet/Russian space program?

There is plenty of information available on NASA spinoff technologies including a Wikipedia page and Space SE question. What innovations are a byproduct of the Russian space program?
8
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185 views

Onboard recording of trans-Mars injection

Is there any video recording of the Falcon Heavy trans-Mars injection burn from onboard cameras? The live feed of the Tesla Roadster and Starman orbiting Earth cycled through multiple cameras ...
8
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310 views

For a launch, how is safe viewing distance determined?

In determining safe viewing distance, seems to me there are discrete threats to consider: First is the rocket blowing up on the pad, or just above it. That would have no warning. There would be a ...
8
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642 views

Roughly how many self-viewing cameras are present in a Falcon 9 LEO mission?

Watch any of last year's SpaceX LEO satellite deployment missions's broadcasts in YouTube, and you can see views from at least several different cameras. At least two on the 2nd stage nozzle, at least ...
8
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141 views

Smart suits in development

This is an offshoot of this question. There's a new generation of space suits coming up (Z-series, anything that the Zvezda NPP has up its sleeves), and I wonder at the level of sophistication of ...
7
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0answers
217 views

What is the “mistake” that caused Doug Loverro to resign as NASA's Human SpaceflightChief so shortly before DM-2?

Today, on May 19, 2020, Doug Loverro announced his resignation. It's a bizarre time to do so, so shortly before the Commerical Crew Program puts astronauts into space for the first time, but even ...
7
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51 views

Is thermal soakback from the engine a problem for rocket stages? Especially ones that complete several burns over several hours (e.g. S-IVB, Centaur)?

Thermal soakback is a phenomenon whereby a hot, operating engine transfers heat into the spacecraft, usually conduction through the engine mounts. I've only ever seen this problem discussed with RCS ...
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37 views

How long do we have contact with a centaur after launch

When centaur separates the payload, we can see a video signal of this happening. The mission of centaur is completed now, but are there still some activities centaur is performing after seperation? ...
7
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135 views

What are the general properties and specs for JWST's onboard data and image processing capabilities?

Answers and comments on What is the data storage capabilities onboard the James Webb Telescope? which reference the James Webb Space Telescope User Documentation item JWST Solid State Recorder mention ...
7
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117 views

Why do Russian rocket engineers call C₂H₈N₂ “heptyl”?

Unsymmetrical dimethlyhydrazine or "UDMH" is a propellant which has been used by Russian, American, European, Chinese, and Indian rockets. Russian rocket engineers nickname it "heptyl". Why was this ...
7
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105 views

How many spacesuits were specifically manufactured for John Young?

John W. Young was a legendary astronaut: The first American in space after the original Mercury Seven, as Gus Grissom's co-pilot in Gemini 3. He got in trouble during this flight for smuggling ...
7
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93 views

Interpolating precise ephemerides of GPS satellites

My objective is to obtain at least a sub-meter position accuracy by interpolation of the GPS ephemerides. There is conflicting research outside, where some authors state that a simple Lagrange or ...
7
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76 views

Time scale separation and cascading control loops

The typical approach to designing flight control systems is to design an inner control loop to stabilize vehicle attitude and angular rates, while an outer loop tracks vehicle position. The reason ...
7
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0answers
124 views

What performance can be expected from chemical rockets under Venusian atmospheric conditions?

Is it feasible to use either solid or bipropellant liquid rocket engines to lift off from the surface of Venus? "Reference datum" air pressure on Venus is around 9.3 MPa; even on the top of, say, ...
7
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136 views

What would a human rocket be like to launch a human off Mimas?

In a comment on Is there a self-rounding celestial body from which an Olympian could jump into space? @jpa made a modest proposal. What if we stacked a bunch of athletes on top of each other and ...

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