Questions tagged [launch]

Questions regarding the takeoff or the liftoff phase of the flight of a rocket and the set of activities required for preparation of the launch vehicle leading to it.

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30
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5answers
4k views

Do any launches bypass LEO?

If sending a payload to GEO (geosynchronous orbit) or any other high orbit, you could start off launching to LEO (low Earth orbit), and then use a Hohmann transfer to raise the height of the orbit. I ...
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When does the space shuttle stop its gravity turn?

I am trying to model the launch of the space shuttle (up to 120km of altitude) from Cape Canaveral, Florida. In order to do so I would need to know when the gravity turn part of the flight starts and ...
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1answer
53 views

Where can I find launch trajectory data of the space shuttle?

I am trying to mathematically model the launch of the space shuttle (up to 120km altitude) from Cape Canaveral Florida. It would be really handy if I could check my calculations with some real launch ...
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2answers
657 views

What sensors or combination of sensors do rockets use during takeoff for their orientation?

I know that after using up rockets and before reaching final orbit, satellites use Earth, Sun, Star trackers to find the absolute position depending on the application and orbit. After that, they use ...
2
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1answer
67 views

How is imbalance handled in the Delta IV heavy?

All the engines of the Delta IV are not ignited at the same time: One of the lateral engine is started few seconds before the other. I imagine there is a good reason for not starting all engines at ...
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6answers
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Why didn't NASA use the shuttle to make a profit?

My understanding is the shuttle was designed as cost-effective workhorse, a space-van to ferry cargo up to the ISS, conduct zero-G experiments and put satellites into orbit. So why didn't NASA take ...
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7answers
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Is it possible to get a spacecraft into earth orbit using Linear Eddy Current Braking on an orbital runway?

The "Space Runway" [I have slightly edited this to clarify some issues that have been raised] Luke Parrish mentioned an unusual and novel space launch method to me. The idea is to get a spacecraft ...
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2answers
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Which STS mission raised the normal engine throttle above 100%, and what change to the SSME made that possible?

As indirectly stated in an answer to How long does Max-Q last?, during later Space Shuttle launches the main engines were operating at above 100% of their nominal maximum thrust. Specifically from ...
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3answers
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How do vehicles get smoothly to a circular low Earth orbit?

Playing Kerbal Space Program, I wonder why they do several burns to get into orbit. Why can't a vehicle get smoothly to it, just pointing slightly off its course? I saw a Soyuz launch at night from ...
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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 ...
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64 views

What factors determine the altitude at which rocket exhaust plumes start blooming hugely?

The images below are from a much larger set of photos in Spaceflight Now's August 8, 2019 article Photos: Atlas 5 paints the sky with spectacular sunrise launch. They show several effects related to ...
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What would happen if one Ariane V SRB did not ignite properly? (there may be no lock-down mechanism)

The excellent answers to What are these circular spots on these Ariane V SRB nozzles? tend to indicate that unlike the IV, the Ariane V simply rests on two flat surfaces under the SRBs at launch time, ...
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Launch Accelerations: Values, history

This topic: What G-forces do different launchers cause? indicates that current satellite launchers are limiting peak acceleration to about 4g. I'm pretty sure the STS (Shuttle) did the same. My ...
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1answer
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What sounds did the Apollo astronauts hear during launch

I've looked through the Apollo Technical Debriefings 11, 12, 14-17, for descriptions of the sounds the astronauts heard during take off. Here is one example, from Apollo 15: *3.0 POWERED FLIGHT ...
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6answers
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Could a Human reach escape velocity by jumping from the surface of Ceres (a dwarf planet)?

According to this answer the surface gravity of Ceres is estimated to be only $0.27 m/s^2$. With a rotation period of 9 hours. The gravity seems light enough to overcome by leg muscle alone, and if ...
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1answer
379 views

What exactly is rhumb-line control in the context of a launch trajectory?

The conference paper SS-520 Nano satellite launcher and its flight result SSC18-IX-03 from the 32nd Annual AIAA/USU Conference on Small Satellites linked in this answer describes the use of rhumb-line ...
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1answer
289 views

SpaceX Falcon-9 fairing heating during launch?

In watching the SpaceX SES-12 launch last night, I noticed what looked like the fairing of the rocket glowing a bit a while after launch. This was most obvious in the SpaceX video SES-12 Mission ...
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6answers
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Can you get to orbital speed with an air breathing engine?

There have been some questions (and answers) that talk about using an airplane as part (or all) of the launch to space. There are active designs that use wings as part of the launch or landing ...
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90 views

Experiments during ascent

Has any astronaut or cosmonaut personally performed experiments, that could only be done by a human in flight, during the ascent phase of a flight. If so, what kind of experiment(s) did they perform?
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3answers
440 views

Could Earth's electric grid be used to power rocket launches via cable?

If our regular huge power plants on the ground could be used to power part of a rocket launch, launch mass would be smaller since fuel would not have to be carried on board. I wonder what are the main ...
3
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2answers
1k views

Is there a lower limit on time-to-orbit from launch?

Since 2013, several launches up to the ISS have taken a fast-launch. First initiated by Soyuz TMA-08M, the fast rendezvous takes the crew up in 6 hours where the previous time-to-dock was around 2 ...
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1answer
76 views

What are the historical fastest and longest time between take off and orbit insertion?

The question is restricted to payloads having described at least 2 orbits. When watching launches, it appears that between launch and orbit insertion, the typical time interval is few minutes (...
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How much did all the space agencies spent on rockets launching and space exploration? What are the benefits for me and you? [closed]

I thought about how much does one rocket cost to build and launch and it came up with roughly $500 million including everything. That made me pause and wonder for myself what it is that's out there ...
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1answer
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How far away can one see a NASA rocket launch?

I live in a Maryland suburb of Washington, D.C., and the weatherman thought we'd be able to see a rocket launched from Wallops Island (alas, it blew up instead) which by car is 166 miles away. ...
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How many rockets have been launched into space? (roughly, of course)

First I was going to ask how many rocket bodies lay at the bottom of the ocean, but I simplified further. Remember, this includes sounding rockets; anything passing the Kármán line. I'm looking for ...
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1answer
697 views

What's falling off the Shenzhou/Long March stack?

Watching the launch of the Shenzhou-11 mission on a Long March 2F, I noticed a number of items falling off the exterior of the rocket. I'm used to seeing chunks of ice sheet coming off of cryogenic ...
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2answers
697 views

Is there any possible way to reduce the cost of a manned mission to the Moon?

Say for instance if we were to build a base on the Moon, how could we possibly reduce the cost to send the parts and materials into space and off to the Moon.
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Was Sea Dragon second stage reusability ever plausible?

Many websites consistently claim that the first stage of the enormous Sea Dragon rocket was intended to be reusable. While recovering a giant booster from sea after a splashdown may seem tricky, it ...
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2answers
4k views

What are “Ohms burns” in the context of Scott Kelly, KSP, and the Space Shuttle?

The Ars Technica video Astronaut Scott Kelly teaches orbital mechanics with Kerbal Space Program (also in YouTube) is a little bit humorous. When Scott Kelley is talking about orbit circularization ...
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2answers
672 views

What is the most number of stages, including fractional stages?

Falcon 9 clearly has two stages, but the smaller two-stage Electron has a "kick-stage" so some might call that 2.5. The question Quantitative benefits of Atlas II's engine-dropping or 1.5 staging? and ...
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3answers
477 views

How do you correct inclination at launch to ISS?

Launching from Florida 28.5 degree inclination to rendezvous with ISS at 400km to 51 degree inclination of ISS
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1answer
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How often were Space Shuttle launches scrubbed?

Reading Mike Mullane's book, Riding Rockets, it seems like shuttle flights were scrubbed, more often than not, during countdown after the crew had boarded, due to some sort of systems failure or ...
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2answers
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What was Apollo 13's “Little Jolt” after MECO?

Disclaimer: This is a question about the 1995 film Apollo 13; I know Hollywood should always be taken with a moon-sized grain of salt, so the question should read as both "Is this true" and "What was ...
4
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2answers
627 views

Compressed gas thruster for an orbital launch vehicle?

Is it possible for a compressed gas thruster to be used to launch a spacecraft into orbit? Let's say, it's already moving at 250MPH(111.7 meters/second) relative to the planets surface. Planets ...
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1answer
2k views

Does the Long March-11 increase its thrust after clearing the launch tower?

The NASA Spaceflight article China conducts first Sea Launch mission with Long March 11 launch of seven satellites links to the YouTube video China’s first sea launch: Long March-11 launches from a ...
6
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1answer
84 views

Orbital insertion accuracy for SpaceX payloads

What is the orbital insertion accuracy of SpaceX for positioning its payload (for example satellites)? How close do they get to the requested or target orbital parameters? I tried to research this on ...
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2answers
281 views

How to reserve places on a SpaceX, Chinese or Indian rocket to send small satellites?

As in a title, I'm searching for a way of reserving a place on a rocket to send small satellites into space. Can it be only done by some kind of launch broker company? Is there any information on how ...
6
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0answers
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Are “launch-on-minute” or other discrete launch times protocols currently the norm for wide launch windows?

This excellent answer to a question about collision avoidance practices for launches begins with: While the length of a launch window varies, launches within the window typically occur at discrete ...
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3answers
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Why does the Falcon Heavy Rocket have a higher payload than the Space Shuttle?

The Falcon 9 heavy rocket has a thrust of about 5,340,000 pounds (23700 kN) with a LEO payload of 140,660 pounds (65.7 t). The Space Shuttle, on the other hand, had a thrust of 6,780,000 pounds (30000 ...
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1answer
109 views

Why aren't rockets launched by a ground explosion through a gun barrel? [duplicate]

I'm watching this clip of a Russian anti-sat or anti-ICBM rocket launched from a silo and of course note that its early acceleration is much higher than for large spacecraft launchers. Why isn't cargo ...
4
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1answer
118 views

What do astronauts have to do for their bodies to withstand launch?

"you have to push your lungs forward through the drag of the atmosphere." That is a quote from Chris Hadfield's YouTube clip for his MasterClass. Is there a list or description of what an astronaut ...
8
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2answers
456 views

Does flying two boosters close together affect efficiency?

When returning the side boosters of the latest Falcon Heavy launch to their landing site, their trajectories keep them right next to each other, and I noticed that a "wall" of vapor is visible midway ...
4
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1answer
133 views

Why does the SpaceX strongback outgas 60 seconds before launch?

I was watching the live stream of the Iridium-5 / SpaceX launch and they mentioned that the strongback would outgas a minute before launch. I assume it was to prevent the strongback from exploding ...
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0answers
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Has SpaceX ever done a hot restart of a 2nd stage?

Another question highlighted this SpaceX commentary for the GRACE-FO launch: Now in order to fly an efficient trajectory for both of the payloads, we’re actually now running the second stage engine ...
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0answers
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How to view the Feb 6, 2018 Falcon Heavy launch?

Will the Feb 6, 2018 SpaceX Falcon Heavy launch from KSC be visible in Boca Raton/ Deerfield Beach area? Is there a good site for determining viewing ranges for launches?
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1answer
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Is SpaceX adopting a strategy to move away from the launch segment into being an operator only to fund the Mars Ambitions? [closed]

The recent approval of the FCC towards the launch of the star-link constellation is indicative that from just being a company in the upstream segment,SpaceX is branching out into the downstream ...
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4answers
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Why do they put a timeline on the SpaceX launch videos?

I have never noticed the SpaceX rocket launch videos include a timeline. This image is from the Falcon Heavy launch with the Tesla car in it.
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SpaceX Canaveral launch question

In the past, I could see space shuttle launches from my front door on the gulf coast of Pinellas County by looking due east on a clear day or night. I have tried to catch SpaceX launches a couple ...
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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 ...
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3answers
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Will the Tesla Roadster return any telemetry?

Is there any equipment fitted to the Tesla Roadster to send signals back to Earth, even for a short time after launch?