Questions tagged [atmospheric-drag]
Questions regarding atmospheric drag which includes the resistance offerd by a moving object in fluid
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What is the reason Starlink satellites took 4 days to re-enter during the accident on February 2022?
I am reviewing the incident that knocked out 39 Starlink satellites earlier this year.
As I explain in this thread, there was a modest magnetic storm on the 3rd of February, which increased ...
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Does a capsule rotate naturally during atmospheric re-entry?
If during atmospheric re-entry a capsule (with a shifted center of mass to produce lift) does not produce any rcs thrust, will the capsule naturally roll? and why?
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How to compute orbital decay of a cubesat?
I'd like to compute the orbital decay of a cubesat in LEO/VLEO due to atmospheric drag. Here is what I've done:
Based on the Satellite Orbital Decay Calculations document coming from the Australian ...
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Is DTM2000 density model expecting adjusted or observed solar flux?
I know two models to calculate the atmosphere density during a satellite orbit propagation. The two models are NRLMSISE-00 and DTM-2000. To feed the models I'm using Space Weather Data provided by ...
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How does "onboard GPS" suggest "escalation speed and severity of a storm caused atmospheric drag to increase up to 50 percent"?
Engadget's says:
A recent batch of SpaceX’s Starlink internet-beaming cubesats met with tragedy on February 3rd when a 49-member cohort of the newly-launched satellites encountered a strong ...
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ISS propagation becomes much more accurate with reduced drag. Any ideas why?
I have currently been testing my implementation of a numerical propagator with the ISS. Without going into much details, the propagator considers Earth gravity (with the GGM03S model including zonal, ...
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How is it provided for that the uppermost stage doesn't orbit with the capsule/satellite together?
After a spacecraft reaches orbit and jettisons its last stage, that stage would be in the same orbit too. What are methods to avoid this, or isn't it cared about?
In case of the Space Shuttle, the ...
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What factors would contribute to a spacecraft's ability to maintain a very low orbit (VLEO) or at least orbits with very low perigees?
I asked What does account for a high coffin corner of a plane? in Aviation SE. Now I wonder what factors would contribute to a spacecraft being able to maintain low circular orbits (e.g. within 200 km ...
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Soyuz: Do you know the coefficient drag and lift to drag ratio are during reentry?
I've been learning Python as a hobby the last two years. I like spaceflight too. Therefore I wrote this code to simulate the reentry of a Soyuz. I'd appreciate some feedback: https://github.com/fra-...
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Using astrogator in STK to separate 2 satellites using atmospheric drag
So I can do an initial separation using Astrogator by using different areas. What I need to do now is to define a distance and at that distance the area that the satellites are propagating changes. ...
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Change in drag coefficient when Dragon flips over on launch escape?
Consider the Falcon 9.
In emergencies, the launch escape system will fire to separate and propel the crew module away from the rocket.
After the engine shuts down, the payload trunk will separate ...
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How would Ingenuity handle Martian Storm and dust devils?
Martian storms are quite common and can sometimes encompass most of the planet. Though the density of the Martian air is low, the speeds are pretty high (some have observed 26 m/s).
How would the ...
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What is the density of the earth's atmosphere at an altitude of four hundred kilometers?
What is the density of the earth's atmosphere at an altitude of four hundred kilometers? I want to use it to calculate the drag on something in orbit near the ISS.
The Jacchia Reference Atmosphere is ...
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Would it be possible to avoid the heat-from-friction problem when re-entering the atmosphere by performing (vertical) "U-turns"?
If you lift a swing at a children's playground and release it will swing back and forth for a while, losing some altitude in each swing, mostly (?) due to drag. Eventually it has lost all energy and ...
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How hard does atmospheric drag push on the ISS? Is it more than one pound?
A comment under this question has me thinking; with it's huge main structure and giant solar panels the ISS presents a very large cross-section to Earth's rarified atmosphere at 400 km altitude. So ...
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What is Direct Simulation Monte Carlo and why is it a good method for simulating spacecraft drag in VLEO?
Reducing spacecraft drag in Very Low Earth Orbit through shape optimisation J. A. Walsh and L. Berthoud (2017) show simulations calculating drag coefficients for different "nose cone" shapes ...
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How many solar system bodies have "knees" in their atmospheres?
Discussion lead to citing Why does Earth's atmospheric density have a big "knee" around 100 km? Is there a good analytical approximation? who's answer is "monatomic oxygen". ...
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How is PICA different from other heat shielding materials?
What are the differences and why did SpaceX prefer to use PICA?
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Changes in Orbital Parameters Due to Drag
Other than STK, are there any commercially software packages available to model changes in orbital parameters due to increases/decreases in satellite drag. I am trying to figure out if aerodynamic ...
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Would this Starship design alternative be viable?
Considering Starship's atmospheric entry, belly dive and "bellyflop",
latest iteration displays four aerodynamic surfaces, two aft fins and two canard fins.
Soon, this configuration will be ...
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Did the Space Shuttle crew have to worry about the ionosphere? What relevant training or specific briefings did they receive?
Comments below this answer tell us that the Space Shuttle always remained in Earth's atmosphere. When it visited the Hubble Space Telescope or the ISS or Mir it was still in the thermosphere and ...
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Why will OGO-1 reenter from an elliptical orbit rather than circularize first?
According to all the sources cited in Why does OGO-1's trajectory and imminent reentry come from sky surveys and NEO tracking rather than normal satellite tracking? OGO-1 is in a highly ...
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Exactly how "Ferrari-like" was GOCE? Was its drag coefficient as low as the car's?
This comment mentions:
This relation between drag and mass is taken to a relative (for satellites) extreme in GOCE which I think needed to be close to Earth to accurately sense the changes in gravity,...
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Why does a satellite with a higher mass fall slower?
I was doing simulations in GMAT and I could observe that if I increase the mass of the satellite, the satellite falls slower ... and if I reduce the mass of the satellite, then it falls faster (I only ...
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How to fit, into a cubesat, 29 trackable high drag subsatellites with well-defined aerodynamic profiles
Johnathan McDowell's recent tweet says:
The @AerospaceCorp Aerocube-10a cubesat carries 29 small passive high-drag subsatellites used to probe the density of the upper atmosphere. 3 have been ejected ...
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What is the difference between "body drag", "frictional drag" and "pressure drag" for astronaut or aerobot atmospheric locomotion in microgravity?
Complaints below my answer to Would a higher air pressure on the ISS or elsewhere make it easier to “swim” in microgravity? about my spherical-cow estimate of how fast an astronaut can accelerate by &...
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How low would a full revolution around Titan and Triton be possible?
A lowest circular orbit to remain stable around the Earth is possible at an altitude of about 95 mi (155 km) while the lowest perigee for a stable elliptical orbit around the Earth would be around 55 ...
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To cool down Venus, from where would be the most economical way to bring the shadowing material into orbit around the planet?
Edit: With the help of comments below, I've changed the question somewhat.
Credit: NASA, Image processed from Mariner 10 images by R. Nunes http://www.astrosurf.com/nunes
It could seem that ...
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How can a meteor gain energy in an encounter with the Earth even though these answers say it can't?
The question Did a spacecraft ever use an atmosphere to accelerate away from a planet? was unfortunately given five down votes and answered with:
Entering the atmosphere introduces drag, which could ...
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Atmospheric reentry drag and friction
What is the difference of air drag in ground level with let say moderate speeds like fast cars 200km/h to 400km/h with high speed vehicle reentry at high altitude where the air is so rarified.
Making ...
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How much of a drag is it, orbiting the Earth in a space suit?
An astronaut in a spacesuit travels around the Earth at the same altitude as the ISS. Let's say the astronaut leads the ISS by 1000 meters along the same orbit.
After one orbit, how much velocity has ...
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Can I push the atmosphere out of the way?
The problem with virtually all methods of giving a launch vehicle velocity before launch is the atmosphere. The higher the velocity, the worse the drag.
In the comments to a recent question, someone ...
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What fraction of Terminator Tape™'s drag comes from interaction with Earth's magnetic field as a function of altitude? Is it ever important?
This answer states that Terminator Tape™ uses the Earth's magnetic field to generate drag to shorten the deorbit time of a spacecraft in LEO. It links to https://sst-soa.arc.nasa.gov/12-passive-...
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Why is "Terminator Tape" electrically conductive?
A 230 foot long tape deployed from the satellite Prox-1 greatly reduced how long it took to deorbit. The tape was described as electrically conductive.
Was that property intended to help the ...
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What does S represent in Chris Hadfield's D = ½ ρ v² S?
Retired test pilot, CSA astronaut and ISS Commander Chris Hadfield's new Master Class advertisement video Chris Hadfield Teaches Space Exploration - Official Trailer - MasterClass is heavily edited ...
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North Korean objects 41332 and 41333; how fast are they losing altitude?
I cited objects 41332 and 41333 launched in early 2016 as counterexamples to this answer on my highly down voted and closed but otherwise "perfect" question What regulations, agreements, or other ...
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Can dust be in orbit around a spacecraft which orbits the Earth or Moon?
In the title above, Can dust be in orbit around a spacecraft which orbits the Earth or Moon? let's define "in orbit" to mean gravitationally bound to the spacecraft long enough to go around it a few ...
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Why is the diameter of the boosters of some launch vehicles smaller than the diameter of their payload fairing?
Whilst watching yesterday's Starliner launch I've noticed how skinny that Centaur (3.1m) looks compared to the CST-100 (4.5m).
Looking up the Atlas V I was amazed to find out that it has even larger (...
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Could SpaceX's Starship's landing and restart process work on Titan?
Gravity on Saturn's moon Titan is much weaker and the atmosphere is far denser than either Earth's or Mars', which Starship seems to have been designed for. Could an unmanned Starship do an Earth-...
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Can effective thrust in the more dense layers of the atmosphere be considered constant (as approximation)?
I am reading some course material about the 'Thrust load ratio'. It states the following:
The thrust load ratio is: $Psi = {T \over Mg}$
$T$ being the effective thrust, equal to the actual (constant) ...
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Are rockets faster than airplanes?
Rockets are fast. Faster than anything else somebody could fly with - at least intuitively to me.
But - airplanes are fast too.
A rocket typically flies vertically, an airplane mostly horizontally.
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What was the exact nature of the observations of "solar flare activity" that delayed the launch of Vostok 5?
The interesting story of Vostok 5 recounted in Encyclopedia Astronautica's Vostok 5 (linked in comments below this answer) includes the following passage:
Vostok 5 was originally planned to go for ...
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How do I calculate re-entry velocity when decaying from a circular orbit?
I am trying to find the velocity of an object during re-entry so that I can calculate the peak heat flux but I'm a bit stuck.
I know how to find the velocity of the original, circular orbit (300km) ...
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What if GOCE rolled 90°?
Reading this question: Is GOCE a satellite or aircraft?
I wondered what would happen if GOCE rolled 90° in either direction, so that it's solar panels become parallel to Earth's horizon, and then ...
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When do aircraft become solarcraft?
Any body travelling through particles undergoes drag. Any body able to generate lift (for instance spheres cannot generate lift) can generate lift if it undergoes drag.
First by assuming one body in ...
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Coupling satellites already in orbit reduce drag and debris?
How would 2 or more satellites be joined to reduce atmospheric drag? Could a 3rd satellite tow and join 2 or more satellites that are in similar orbits to prevent Kessler syndrome?
At the very least ...
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What would be payload capacity of reusable Falcon 9 if there was no atmosphere on Earth?
Reading this question and answers, I wondered what would happen if there was no atmosphere, everything else being the same on Earth.
What would be the payload capacity to LEO of Falcon 9 in reusable ...
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Maximum speed based on atmospheric altitude given maximum temp?
I saw the question Could escape velocity be achieved in the atmosphere? and thought it probably could've been asked better.
I'm sure there's an equation to calculate the average heat generated by an ...
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Why not increase contact surface when reentering the atmosphere?
If a craft were to increase the surface area where contact is made with air during reentry, I imagine the heat quantity per area unit would decrease, making the use of (heavy) heat shields less of a ...
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Reducing the aerodynamic drag of multi-engined rockets: aft wake area
Have there ever been thoughts of reducing the aerodynamic drag that results from the empty space between rocket engines? More precisely, this extremely low-pressure area sucks up ambient air and ...
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