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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Did the space shuttle fly straight "up" when leaving Earth?
I was watching space shuttle launch recently, and at 2:53 you can see the space shuttle from an angle, even though it's high above the earth and you should see only the bottom.
Did the space shuttle ...
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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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How do launches avoid leap seconds? Why?
A short comment in the BBC Crowd Science audio program Does Time really Exist?'s discussion of the slow divergence between UTC and TAI (IAT) (coordinated time and international atomic time) says that ...
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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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Why are rocket launches so loud?
In reading an answer here: How close can I get to a rocket launch and not get killed?, the comment is made that noise from the launch can be tremendous. This isn't a big surprise to anyone who's ...
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What is the problem with aborting a Space Shuttle launch?
In the question Why didn't the Space Shuttle have a launch escape system? there was discussion in the commentary about why the Space Shuttle could not safely abort through much of its envelope.
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Pros and Cons of LH2/LOX vs Other Fuels
As I stated in the answer to another question, LH2 suffers some serious drawbacks compared to other fuels.
Off the top of my head, they are
Extremely low density, resulting in:
Lower mass-fraction ...
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Most recent launch of a nuclear reactor, and current barriers to launching the next one?
The question What happened to Kilopower generators? about Kilopower nuclear reactors got me thinking.
Answer(s) to How many nuclear fission reactors have been launched into space? How many are still ...
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Was there any launch vehicle possible that could have been used for a heavier New Horizons with enough fuel to enter Pluto orbit? (adding ~10 years)
Answers to the Astronomy SE question Can New Horizons probe turn back and start orbiting Pluto are of course no, it would have to have been a different mission with a lot more fuel and a bigger launch ...
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Where is the best place to get a time history of launches and satellite numbers
There are a number of places you can find details about currently operational satellites, and a few sources for past values. Is there a reliable source that has the dates of each launch and how many ...
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Apollo/Shuttle launch site fuel handling
I read somewhere that fuel was delivered to the Apollo launch site by tanker truck (for cryogenic propellants) and rail cars (for the kerosene). Were the fuels transferred directly from delivery ...
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What "actually" happens at T-minus-0
In most American rocket launches, the "counter" will say:
3,2,1 [awkward pause], and liftoff....
So what truly happens at T-0? Is there any standardized event that this time indicates?
Is the ...
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Why was InSight planned to launch from Vandenberg?
Why does the InSight Mars lander mission intend to launch from Vandenberg, which does not allow for prograde launches? Will it launch into polar or retrograde orbit? Why? It will do an interplanetary ...
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Is there any advantage in launching spacecraft from a high latitude, or why was Plesetsk built so far north?
For launching satellites or other spacecraft, there is a significant advantage in being close to the equator: angular momentum helps in gaining initial speed and one can launch into any inclination. ...
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Why did the Saturn V stage fairing appear to burn after separation?
This video shows the stage separation of the 1st stage of Apollo 4 (incorrectly identified as Apollo 11) followed by the jettisoning of the ring-shaped fairing between the two stages.
The moment the ...
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Ariane 4: shroud around stage?
In this image of the Ariane 4, you can see a blue shroud around the second stage.
At least I think it's a shroud. It is present in many photos of Ariane 4 launches, but the drawings I've seen omit ...
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How close can I get to a rocket launch and not get killed?
There was a question regarding the closest distance regular people are allowed to be near a rocket. At that distance (Baikonur I, 1.1 miles, 1.8 km), even if a rocket explodes, there is a small chance ...
user6738
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What was the most busy week in space launches?
In the history of space launches, which week has had the most space launches? It would be also nice to know the second and third place.
I think its also interesting to ask about most busy month and ...
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What is the largest hurdle of the mission to Mars?
I was shocked when I recently found out just how long it takes to get to Mars. I've been conducting a very informal survey amongst peers of how just how long people think it takes us to travel to Mars....
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What does it mean for a launcher to be 'nuclear-certified'?
This article says NASA has booked a nuclear-certified Atlas 5 for the launch of the Mars 2020 rover, and says this:
currently, Atlas 5 is the only launch vehicle that holds a NASA
certification ...
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Could a ship take off from Earth using ion thrusters?
If you had enough ion thrusters, could you take off from Earth's surface into low Earth orbit?
If not, why not?
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Why did the Space Shuttles perform a rollover maneuver during launch?
I want to understand the reasons why the shuttle did the rollover manoeuvre after launch.
I would think better to do it earlier after launch while the air flow pressure is low.
Why not just adjust ...
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Highest number of satellites launched on a single rocket
What is the highest number of satellites that have been launched on a single rocket? What were the number of stages used in that launch?
(It may be from the past or a future mission)
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What are the biggest challenges for high altitude rail-gun launch systems?
Use a maglev railgun for initial acceleration - in a new, hyperbolic tunnel facing eastward - this exits from the burrowed -undergrade- track
to Equadors' Mt. Chimborazo peak - (a mountaintop both 6 ...
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Could a human jump off Mimas without return?
A similar question has already been asked on dwarf planet Ceres:
Could a Human reach escape velocity by jumping from the surface of Ceres (a dwarf planet)?
Ceres has 2.9% of Earth's gravity. Saturn's ...
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How do cubesat owners first find out their cubesat's initial trajectory? How do they point antennas at it before official TLEs start to appear?
When cubesats are first deployed it can sometimes take several days before they start appearing in official TLE distributions, and even then if many were deployed it may take a lot more work to decide ...
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Coefficients for linear tangent steering law
Given certain simplifying assumptions, a "linear tangent" steering law is optimal for orbital insertion of a launch vehicle:
$$\tan \psi = a\cdot t + b$$
i.e. the tangent of the flight path angle ...
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Generating plot of LV's performance as a function of the C3 parameter
Following my previous question about Ariane 5 performance data for escape missions, I would like to know how the plot of launch vehicle capabilities like the next one are obtained:
More specifically, ...
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Upper stage structural loads on ascent?
In another question, this came up:
For example, if a Falcon 9 launches 20 tons of fuel to dock in LEO, how can the same upper stage be used to launch 40 tons of fuel to the same orbit? Doesn't it ...
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What is the highest inclination orbit ever attained from a Cape Canaveral launch?
The launch facilities at Cape Canaveral, FL are located at a latitude of about 28.5° N, so that puts a hard lower bound on inclinations from that site. I assume there are well-defined azimuth limits ...
user29
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From 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 can I find sources for Launch Trajectories?
The trajectories of space launches and the deployment of their payload (both scientific and commercial) are certainly carefully monitored by the space agency or company providing the launch capability,...
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Is there anything like a standard for maximum temperature for mission-critical electronics in spacecraft?
In addition to radiation, acceleration, and vibration, a launch vehicle can encounter excursions in temperature, and critical electronics for guidance and control should probably be resistant to ...
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Could fuel be "hosed" (pumped) from the ground to a launcher?
Most fuel on board a launcher is used during the first couple of minutes. Most of the propellant is needed to carry other propellant. For example, Saturn V (kerosene) and Delta IV (hydrogen) use about ...
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Why is SpaceX considering Methane as fuel for their next engine, the Raptor?
Currently, SpaceX has developed the Merlin 1 family (1B (Falcon 1), 1C (Falcon 9 v1.0), 1D (Falcon 9 v1.1/F9-R/Falcon Heavy), vacuum versions and sealevel versions) which are LOX/RP1 based. (75-...
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Can gunpowder get you to the moon?
In 'From the Earth to the Moon' (1873) by Jules Verne, A huge cannon is used to send a spaceship to the moon. A lively discussion in chapter IX leads to using 400,000 pounds of fulminating cotton to ...
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Why didn't the Space Shuttle have a launch escape system?
Since the very beginning of space exploration, rockets had some sort of Launch Escape System (LES). From this Wikipedia article, we know that Mercury and Apollo had an escape tower, while Vostok and ...
user55
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Why was AMOS-6 mounted on the rocket for a test fire?
I understand that the static test is a general test of pre-launch procedures, but risking a multi-million dollar payload for a test seems remarkable. Couldn't they use a mass simulator or something? ...
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Why not travel to Mars in 2 months?
Just to clarify: I've made some research and generally know what the case is, didn't mean to make the question sound stupid. :)
I know there is a thing called Hohmann transfer orbit, named after ...
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Is there any non-rocket spacelaunch concept within reach of current material science and technology?
Suppose for a moment that cost would be no issue (and noone brought pruning shears) - could we build any of the non-rocket spacelaunch systems from earth listed here or elsewhere? Which one is the ...
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Is it more efficient to assemble spacecraft in orbit, or assemble on the ground and launch?
My friends and I were trying to figure this out a while ago.
I was thinking that by transporting smaller pieces into space via a lighter re-entry spacecraft, there would be overall less fuel used ...
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How much propellant is used up until liftoff?
How much of the total propellant mass (fuel+oxidizer) of the first stage/boosters is usually burnt between ignition and liftoff?
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Why did Apollo use roll and pitch maneuvers similar to Space Shuttle to establish ascent trajectory?
When the Space Shuttle launched, it would perform a roll and then pitch to establish its ascent trajectory. There is fairly straightforward rationale for this. The vehicle's aerodynamic shape, the ...
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Why did the recent Sirius FM6 launch use such a high inclination?
Earlier today a Proton-M rocket took off, carrying a Sirius FM6 satellite radio payload destined for geosynchronous orbit. Nothing super exciting, Briz-M upper stage for transfer burns and then the ...
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How long does it take to get to ISS?
The ISS is in orbit about 250 miles high, the students in this related question get 62 miles in less than a minute. This NASA Press release indicates the The Soyuz TMA-13M launch on May 2014 has a 6 ...
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Horizontal space launch
Space ships are always launched vertically. Its reason is pretty obvious: vertical launch has the lowest distance between the desired height and surface.
However, would horizantal launch be worth to ...
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Which launch was the first to use a dogleg maneuver?
Jake Blocker's excellent answer to How does one dogleg from Florida to a sun-synchronous orbit? explains what a dogleg maneuver is, what it's for, what it looks like, and even what a real dog's leg ...
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How far south can one see a rocket launch from Cape Canaveral, Florida?
I'll be in Miami this Thursday 30th of March and there is a SpaceX Falcon 9 rocket launch from LC-39A, Kennedy Space Center, Florida (if it's not delayed).
I won't be able to drive north to be on ...
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GSLV MK2 vs Falcon 9 - Reasons for Huge performance difference
Yesterday ISRO operated the GSLV MK2 launch vehicle, which is a medium lift launch vehicle with a capability to lift 5 tonnes to LEO.
I just compared Falcon 9 with GSLV MK2. Falcon 9 capability to ...
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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-...
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