Questions tagged [physics]
How physics applies to a particular activity in space or to getting to space.
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What will be the escape velocity for a human body?
Now imagine an average man of 70kg floating in space with no gravitational forces acting on him. Now a pebble(25 grams) spawns into existence near him. So now there's a gravitational force between ...
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Is there less blue light available because the sky is blue? [closed]
Are the things we see that are blue .... less blue during daytime because the sky is blue (less blue light available to eluminate the ground)?
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When a spacecraft reaches the event horizon of a black hole, what happens to its residual gravitational potential energy?
A spacecraft falling from infinity directly towards a celestial body accelerates until it impacts the surface at the surface escape velocity. For any celestial body, the escape velocity is ...
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Do larger less dense objects heat less while entering the atmophere?
When a space craft enters the atmosphere, it gets hot and heat shielding is needed. Do objects with more surface area and less density heat up less then heavier, smaller objects? Could an object with ...
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Lorentz force space propulsion
While browsing for Space propulsion, I've found the following article
As shown in Figure 2, the conductor I0 gets through the coil L0, and they are fixed together and form a system. a is the main ...
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Is it possible to avoid tearing apart from a blackhole if moving fast enough?
I have a spacecraft zooming directly into a blackhole with constant thrust.
Considering the gravitational force of that blackhole and that there is no terminal velocity to slow me down.
According a ...
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Spacesuit with no thermal insulation. Would person inside freeze or overheat?
Let us say I have a theoretical super thin spacesuit which has zero thermal insulation. As if person would be naked in space, but all other variables - pressure, oxygen, food and other life support ...
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Two different Hill equations for space rendezvous
I have stumbled upon two variations of Hill’s equations across numerous scientific journals:
Why are the mean motion’s positive and negative signs of these two Hill equations reversed? And are these ...
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Will the initial velocity of an object in space get multiplied if a constant acceleration is applied? [closed]
Imagine an object travelling in space in the speed of 60 Kmph which took acceleration x
if accelerated with the same x, will the object travel faster than 60 Kmph or travel in the same speed cuz of ...
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What am I missing about rocket nozzle isentropic flow?
Playing a bit with Cpropep-Web, something looked wrong to me about how it models isentropic flow through a CD nozzle.
I'm taking the RS-25 characteristics as an example. I ask for a frozen equilibrium ...
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If Earth had a second moon, where would it be positioned? [closed]
Could Earth theoretically have another moon, beside the existing one, that would have a stable orbit? If it is possible, could Newtonian physics describe where it would be (i.e its position relative ...
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Dependance of slosh mode on ratio of liquid height to tank height
If two liquid tanks of the same cross-section but different heights have the same liquid up to the same depth, will sloshing be the same or different in both tanks?
I would assume they would be the ...
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If anything, weren't the first people in orbit the first who broke the sound barrier in free fall?
Felix Baumgartner and Alan Eustace are said to have broken the sound barrier during their space jumps. But in space, there is no sound. In fact, they were still within the Earth's atmosphere so there ...
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What is this thing that goes zipping past the Electron launch?
Watching the Electron launch 07 October 2022 on https://www.rocketlabusa.com/live-stream, what do I see in the video at T + 9:12, just after they confirm secondary engine cut off?
I thought it was a ...
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Satellite’s Position and Path on 2D Map [duplicate]
When the ISS orbit the Earth, its path traced on a 2D Mercator Earth Map is similar to a sinusoidal wave. I am wondering is there any way to determine the trig function of the wave, knowing the ...
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Ion propulsion system [duplicate]
Good evening.
Is there a formulae to calculate how much lift an ion propulsion system would create on earth, given factors like voltage, load, etcetera? Just a mathematical formulae. That is all I ask ...
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How much solar radiation hits a spacecraft in transit to Mars?
How can I solve for the amount of radiation that hits a Mars transit vehicle, in transit? What formulas should I use? I am mostly focused on solar radiation.
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How to calculate catalyst bed geometry (length/radius) for a monopropellant thruster?
Catalyst design is central to the development of monopropellant thrusters and hence, ignoring its importance, as I have realised, is not very good practice. My question is if the mass flow rate, bed ...
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What is measured with g-forces?
When sitting at rest, a typical "g-meter" shows a value of one, however the meter is not accelerating. In orbit, it shows zero, but is under constant acceleration. The actual force of ...
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Could a spacecraft theoretically fly a smooth, curved arc of a turn in space like an aircraft?
I understand there in no air is space which is what allows an aircraft to fly a curved flight path. This is strictly a theoretical question given today's technology. Here are the conditions:
There ...
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Inconsistencies in calculating exhaust velocity
I'm quite sure this is either a small or just plain stupid mistake but my anxiety is getting the better of me. when calculating exhaust velocity this is the equation used:
however I keep getting ...
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Gravitational field of the Moon and Earth
Is there any method to find a point or plane in space where the gravitational field of the Moon and Earth are the same?
And if so, what happens to a spacecraft if it passes through that point or ...
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How to plot a satellite's orbit around Earth in MATLAB?
Given orbit height, mass and initial velocity how should I plot a satellite's orbit in MATLAB? I was hoping to use verlet integration (I need to implement a solver) possibly the velocity-verlet. I ...
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How does Spinlaunch manage the counterweight right after launch?
Spinlaunch has successfully launched a suborbital test vehicle from a 1/3 scale demonstrator, see for instance aviationweek.com or space.com.
While spinning up the arm, perfect balance is achieved ...
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How much energy is lost by damping yaw from a SpinLaunch?
SpinLaunch hopes to launch a 200 kg satellite from a ground-based centrifuge, at 5000 mph, and more troublingly, at 450 rpm aka 7 tumbles per second.
(The 3000 rpm figure mentioned in its tech sheets ...
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Why is the sunny side of JWST's sunshield purple and covered with silicon?
After about 08:52 in Destin's Smarter Every Day's Why Are there Holes in the James Webb Sunshield? (Explained by My Dad) - Smarter Every Day 270 (linked below) ...
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Why is the eccentricity vector used to describe near-circular orbits?
When dealing with near-circular orbits I've seen the usage of the eccentricity vector defined as
$$(e_x,e_y) = (e\cos\omega, e\sin\omega)$$
I've seen this in Schaubs' "Analytical mechanics of ...
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What do/will "quantum gyroscopes using nitrogen-vacancy centers in diamond" for space applications actually look like, and how do they work?
The NASA page ELaNa 41 Mission has a section labeled QubeSat - University of California, Berkeley which says:
QubeSat is a technology demonstration mission. It will test and characterize the effects ...
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To what percentage of the speed of light you need to accelerate to get artificial gravity at 1g?
Let's say you have a very powerful hypothetical fusion or matter/antimatter drive on a spaceship and you want to travel to a star nearby. Can you get 1g artificial gravity by accelerating? Or close to ...
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Questions about orbital ring math from Birch 1982 paper
I have been reading the original Paul Birch paper published in JBIS 1982. I have been using this copy found here.
In particular I am wondering about generalizing the ideas, like for a different planet ...
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How does gravity change beyond L2?
Why does gravity appear to increase again on the far side of L2 from earth as indicated on the gravitational contour diagram? One would expect gravity to continue to decrease as the distance from sun ...
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Would the ship using the Alcubierre drive need to use conventional propulsion to move during warp? Or would the space-time "wave" push it?
I have found various explanations on how the warp drive works. And right now I'm confused. First I thought warp drive works by expanding space-time behind you, and contracting it in front of you. I ...
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Could you survive very high G's if your whole body was accelerated uniformly?
Could you survive high g's if your whole body was accelerated uniformly (not just by the seat of a rocket pushing on your back)?
Your body is really only affected by gravity if you are touching ...
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Understanding g₀ to calculate delta-v
I am trying to calculate the exact delta-v from various existing upper stages with a given payload in a vaccum and in orbit, say LEO. I understand that according to the Tsiolkovsky rocket equation:
$$\...
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What can be determined about an orbit if it passes through two points
Using a 3D Cartesian coordinate system if we know for certain that a craft will pass through two points in it's orbit (let's call them p1 and p2) and we also know the mass of the central body it is ...
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What is the best place on the internet to learn basic physics needed for rocket engineering? [closed]
Does anyone know a site where everything is in one place and it teaches equations and pricipals from the basics?
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Can a space craft realistically eject flares to evade a missile?
I was watching Behind Enemy Lines, and one of my favourite scenes is the jet attempting to evade the missiles.
All this got me thinking about the Defiant from Deep Space Nine, and some research shows ...
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Given 10W and a 100 m^2 target to look for from LEO, which can search a larger area; SAR or LIDAR? (back of spherical cow-shaped envelope question)
Background
For the project discussed in Space based active optical sensors for maritime surveillance the concern seems to be that SAR is off the table because a low inclination orbit is in eclipse ...
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What is MAHLI's theoretical or expected best optical resolution? How was it defined? Was it verified on Mars?
The block quote in this answer to Has Curiosity ever taken a good hard look at the dirt covering its top surface? Can it? Have individual particles been sized? says that at a focus distance of 2.5 ...
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When burns are made during inefficient parts of the orbit, where does the lost energy go?
Any Kerbal Space Program player will know that burns prograde and retrograde to the velocity vector are most efficient closest to the body being orbited, while burns normal and anti-normal are most ...
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What is the theoretical smallest size limit for a phased array antenna that can reach LEO?
Now that one provider is operating a phased array ground-to-satellite internet comm system, others will follow. A frequently asked question is "When can we use Starlink with a sat phone?". ...
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What's the farthest an ISS astronaut gets from the station's center of mass during routine activities? At 0.5°/s what centrifugal effects are there?
This answer to Are there really “Dead End” signs on the outside of the International Space Station? won't be helpful here since for the purposes of this question spacewalks aren't part of routine ...
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Modeling a rocket using Tsiolkovsky's equation and ordinary differential equations
So I have this uni assignment to make a model out of ODEs, and my idea was to use rockets. After some research I found about Tsiolkovsky's equation and tried using it on a Falcon 9 (disconsidering ...
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Estimating thrust and kg fuel for a generation ship's journey to Alpha Centauri
Premise: A generation spaceship leaves Earth around the year 2060 on a journey to colonize Alpha Centauri A (ACA). In this fiction, fusion power is achieved in 2040, improved over 20 years, and used ...
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If an astronaut threw a cup of coffee into space, would it freeze, or boil off into gas?
If an astronaut threw a cup of coffee into space somehow, would it freeze into a block, or boil off into gas due to the zero pressure?
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Would hypothetical aliens from super-earths be larger and stronger then humans? [closed]
I’m curious how physics would affect the size and strength of human like aliens on super-earth worlds with 1 to 2 times the gravity of earth compared to humans. Would they be similar or be larger or ...
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How does Curiosity's X-ray diffractometer work? Does it measure only one angle at a time or does it have an area detector?
Per this answer to Are quasicrystals common on the Moon and Mars?, Curiosity has an X-ray diffractometer.
X-ray diffraction from 3D crystals can (begin to) be understood by embracing Bragg's law. A 3D ...
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Why can solid rockets be both the skinniest and most spherical launch vehicles while liquid fuel rockets have a more limited range of aspect ratios?
Question: Why can solid rockets be both the skinniest and most spherical launch vehicles while liquid fuel rockets have a more limited range of aspect ratios? Are there fundamental engineering ...
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Is a PhD in space-related technology from a Physics background possible?
I am 24 years old, from Argentina. Next year I will finish my 6-year degree in physics from the University of Buenos Aires (We've been told that it is equivalent to a master's degree, but maybe is ...
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If you travelled at exactly the speed of light, what would the stars look like behind you? [closed]
If you were in an Alcubierre drive bubble travelling at exactly 1 c, I wonder what it looks like if you looked back, to the direction you come from. If you went faster-than-light you'd obviously see ...
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