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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 ...
14
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0answers
275 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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286 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 ...
12
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607 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 ...
12
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115 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 ...
12
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0answers
194 views

At what surface gravity can't astronauts do full steps anymore?

We know that on the Moon in ~1/6 g the Apollo astronauts couldn't make full steps because they jumped with each step. At what surface gravity could you walk more like on Earth and at what gravity ...
11
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175 views

Reentry without pressure suits in Apollo: was there a formal risk assesment?

In Apollo 11 Flight Journal the following is stated: The crew will make re-entry without suits or helmets on. Although this was a controversial decision on the first Apollo flight, Apollo 7, when ...
11
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0answers
114 views

Launch to orbit delta-v penalty from Venus compared to Earth?

Thinking about the no atmosphere caveat here made me think of Venus, which is the opposite of no atmosphere for solid/rocky bodies in our solar system. Earth's low orbital velocity is about 7.8 km/s. ...
11
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152 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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0answers
115 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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112 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 commentor asked the title question and was encouraged to make it a new question, but apparently never did. The linked question is referring ...
9
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75 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 ...
9
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103 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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144 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 ...
9
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71 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 ...
9
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394 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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402 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 ...
9
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358 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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90 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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225 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 ...
8
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184 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 ...
8
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151 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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135 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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151 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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313 views

Why ISS Astronauts have red stripes?

After seeing the interesting question How do ISS astronauts “get their stripes”?, I was wondering why the color red was chosen for the identifying stripe: I am assuming that red is the best color ...
8
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185 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 ...
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168 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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186 views

Which engine worked the hardest to keep the ISS in orbit?

The ISS has spent two decades fighting drag caused by its large size and huge solar panels pushing through the tail-end of Earth's atmosphere only a few hundred kilometers above its surface. Question:...
8
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247 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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184 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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139 views

How much delta v is required to keep a low Lunar orbital station stable?

I'm interested in studying where in Lunar orbit a station could be deployed. Due to mascons, Lunar orbits below about 200km will eventually decay according to this answer. Presumably, if the goal of ...
8
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518 views

Can you enjoy a cold carbonated drink in space?

I will grant that launching a can of soda pop, or beer into space would be very expensive. Alternately it is not unreasonable to make it in the space station, carbonated drink makers are easily ...
8
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0answers
627 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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274 views

Why did the frequency of TLEs for the Hubble Space Telescope drop by a factor of 3 in 2009?

I noticed that the TLEs for the Hubble Space Telescope (HST) are posted almost twice a day. Then I looked back in time and saw that this rate varies quite a lot! The plot shows the time interval ...
8
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140 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 ...
8
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0answers
1k views

Convergent-Divergent / De Laval Nozzle Dimensions

I'm creating a super sonic ping pong ball cannon like the one recently shown on Mythbusters. I plan on using pressure rated steel pipe so it's as safe as realistically possible and showing it off at ...
7
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67 views

How long does the SYLDA fairing stay in orbit after deploying?

For dual-manifest missions, Ariane 5 often uses the Système de Lancement Double or SYLDA system to encapsulate the lower of two stacked satellites. It can be seen in the following image encapsulating ...
7
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124 views

What went wrong in the Chandrayaan-2 mission with the Vikram lander?

On September 7th 2019, ISRO attempted to land a lunar lander ,Vikram, with rover , Pragyan, on the moon. It was very exciting to watch until the lander lost communication with ground station during ...
7
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84 views

Dealing with lunar regolith

NASA has announced its intention to return astronauts to the Moon by 2024. Various other questions and answers here address the many dangers and difficulties posed by the fine and abrasive particles ...
7
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76 views

When might we get fourteen people in space?

The record for the number of people in space at one time is thirteen, which has been set a few different times (as discussed in this question, this other question, and this article). In order: March ...
7
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191 views

Why are space tools shiny

I was watching one of the broadcasts of a space walk on the ISS. I noticed the Pistol Grip Tool (Thanks Courageous Potato) looks like its made of polished stainless steel. Why do these tools have ...
7
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179 views

What's the shiny triangular feature on this Progress vehicle?

Picture from here What's the shiny, slightly curved triangular plate with rails above it? A larger version, cropped from here, thanks to a comment by ohsin.
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223 views

How is Mr Steven piloted when catching a fairing?

Mr Steven is the ocean-going vessel used by SpaceX in its attempts to catch re-entrant Falcon 9 fairings for possible reuse. How is this ship controlled during fairing catch attempts? Is she* manned ...
7
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171 views

What is Tiangong-2 doing?

Some news in various outlets following some twitterings including this tweet by Jonathan McDowell about Tiangong-2 performing a sizeable orbit-lowering, followed by a re-raising: ‏ OK now that's ...
7
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779 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 ...
7
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334 views

Common Berthing Mechanism Dimensions

I've found detailed information on the International Docking Standard, enough to start work on a detailed CAD of the mechanism. (http://www.internationaldockingstandard.com/download/...
7
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294 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 ...
7
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681 views

ISS - Tiangong 2 minimum safe distance

Using the SGP4 propagator, I calculated the minimum distance between ISS and Tiangong-2 for this year. I obtained 12.32 km for 2017-09-27 17:29:36.376 UTC (which ...
7
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109 views

Is anything being done to honor Gene Cernan today? (14 Dec. 2017)

14 December 1972 05:40:56 UTC US astronaut Gene Cernan returned to the Apollo 17 Lunar Excursion Module, becoming "the last man on the Moon" for forty-five years, so far. (as reported in my Space ...
7
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272 views

Have LAGEOS' germanium corner cube reflectors ever been used?

When I was writing this answer about the LAGEOS satellites, I notices that four of the over four hundred corner reflectors are made of optical germanium rather than fused silica. Fused silica (FS) ...

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