Questions tagged [hohmann-transfer]
An orbital maneuver to transfer between two circular orbits consisting of one burn to enter the transfer orbit and one to circularize in the final orbit.
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Is it (theoretically) correct to apply an equation that is derived from a hyperbolic trajectory, to an elliptic transfer orbit?
The equation in question is this one:
$$v^2 = v_e^2 + v_{\infty}^2$$
and it is showed in this answer.
The Escape velocity page on Wikipedia mentions a link (num. 4) to the book "Fundamentals of ...
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If one Starship can transport 100 people to Mars, how many could it safely land near Mercury's north pole after one Hohmann-like transfer?
Personally, I would rather live near Mercury's north pole than anywhere on Mars mainly because:
The permanently shadowed craters harbor abundant water ice and other frozen volatile materials
Mercury ...
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When is the supersynchronous orbit more efficient than a typical Hohmann transfer where inclination change and circularization are simultaneous?
The title essentially explains it all. Some GEO launch vehicles like Proton, which launches from Baikonur at a latitude of 46 degrees, launch into a supersynchronous orbit. So at what point is the ...
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JWST Halo Orbits for Dummies: can halo orbits be usefully approximated by Simple Harmonic Motion?
Halo Orbits for Dummies: can halo orbits be usefully approximated by Simple Harmonic Motion?
I am an undergraduate in the Kerbal Academy of Astrodynamics. Patched conics have given me an intuitive ...
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Calculating time for several transfer orbits
I was watching a video that displayed how the time to get to Mars varied with the production of varying delta-v and was looking for the mathematics behind such a calculation. Here is the link to the ...
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Why can't you travel to Mars in a straight line?
I had two questions regarding choosing a path to Mars. Firstly:
I wanted to have a look at the mathematics behind the reason as to why we choose Hohmann's transfer over a journey that is a straight ...
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How much delta-v could be saved with a Hohmann-like transfer orbit to the aphelion of Mercury 's orbit instead of its perihelion?
I wrote "Hohmann-like" of course because Mercury's orbit is rather eccentric and has an inclination of 7 ⁰.
From this factsheet I've learned that perihelion is at 46 million km and aphelion ...
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GMAT B-plane Transfer to Mercury
I have been fighting with GMAT for about 3 days now trying to get this transfer to converge so literally ANY assistance and advice would be greatly appreciated.
I need to do a direct hohmann like ...
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How to perform a Hohmann-like transfer to mercury on GMAT
I am trying to simulate a Hohmann-like transfer from Earth to Mercury and establish an orbit there on GMAT.
I have the following values already:
launch velocity (22.25 km/s)
Launch burn (-7.53 km/s)
...
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Hohmann transfer using GMAT software
I am trying to plot an orbit using gmat. I fixed apogee(RadApo) and perigee(RadPer) for the inner orbit(green) and inserted an impulsive burn.
I got the desired shape of the outer orbit but I am ...
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delta-v for a trip to Bennu asteroid
101955 Bennu has a mean diameter of 490 m (1,610 ft; 0.30 mi) and was the target of the OSIRIS-REx sample return mission. What is the delta-v using a Hohmann transfer orbit to do a round trip from low ...
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How to keep the phase angle with an Hohmann transfer?
I am studying the drag make up maneuver. In this maneuver, I need to go from point A to point B keeping the same phase angle as shown schematically in this picture
When I've approached this problem, ...
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What's wrong with my bielliptic transfer calculation?
I'm trying to calculate the delta-v needed to get from a 200 km circular orbit to a geostationary orbit. GSO is at an altitude of 42164140.1029448 m and at a speed of 3074.6611762 m/s. Because $\frac{...
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Is there a standard 'low orbit' for other solar system bodies?
Is there a standard or convention for what 'counts' as a low orbit for other solar system bodies?
I'm currently writing code for computing arbitrary Hohmann/ patched conics transfers, and I am looking ...
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Are the delta-V requirements for outgoing Hohmann transfer the same as for incoming between two specified semi-major axes?
From a specified circular orbit it is often said that it is easier to go out than in, referring to the fact that achieving escape velocity from a circular orbit takes less delta-V than achieving zero ...
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Determining the launch period for Hohmann transfer
How do you determine the day of a specific launch? I know there are launch windows but they only refer to the time at which a spacecraft must be launched.
For a LEO it is apparently 365 days, but what ...
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Direction of heliocentric entry velocity for fly-by coming from interplanetary Hohmann transfer?
I'm following Curtis's equation on interplanetary transfers. I'm confused by the direction of the entry Heliocentric velocity for a fly-by.
If the assumptions is that orbits are:
Coplanar, cofocal ...
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GMAT: How to do a Hohmann transfer from a larger orbit to a smaller orbit
I've figured out how to do a Hohmann transfer to a larger orbit but can't seem to figure out how to do one back to a smaller orbit (e.g. GEO to random smaller orbit). Any advice would be amazing, ...
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Hohmann transfer orbit Burn Duration
Hohmann's orbital transfer is explained in theory in terms of instantaneous impulses, but in real life instantaneous impulses do not exist. Finite burn is used instead.
How is the burn duration ...
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Minimum deltaV between two Orbits (re Jonathan McDowell tweet)
In this Tweet Jonathan McDowell estimates the required delta V between an object and a projectile.
I have recalculated the ejection velocity of the Kosmos-2543 projectile. The delta-V between Kosmos-...
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What makes Earth-Mars transfers more non-Hohmann; inclination or eccentricity?
Answers to Why do many Mars missions launch now, if the Hohmann transfer orbit is the most propellant-saving one? and discussions below them made me wonder what makes Earth-Mars transfers more non-...
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Mars versus the poles of Mercury WRT colonization
From MESSENGER Finds New Evidence for Water Ice at Mercury's Poles :
Credits: NASA/John Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington/National Astronomy and ...
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Orbital Rendezvous vs Hohmann Transfer
Let's assume that
a spaceship (capsule) is about to dock to the ISS
the distance between spaceship (capsule) and ISS is 20 meters
the relative velocity between the spaceship (capsule) and ISS is ...
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When doing an interplanetary Hohmann transfer, are additional escape and capture burns necessary in addition to the two Hohmann Transfer burns?
When doing a Hohmann transfer, it takes a burn to change from a low orbit to the Hohmann Transfer Orbit (HTO), and a second burn to change from the HTO to a high orbit. I know how to find the delta-v ...
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Could we wait for Mars to come to us?
This may be a stupid question but I didn't find much information online about it. The concept is simple, could we launch a vehicle into space from Earth, stop right on Mars trajectory and wait for the ...
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Mars and back, staying only a few days
This article states that
once you arrive at Mars you'll only have a couple of weeks before you'd have to begin a fresh Hohmann transfer back to Earth, otherwise you'll have to hang out on Mars for ...
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Circular to elliptical orbit delta V requirements
this might be a dumb question, but i've been recently trying to calculate the delta V to deorbit a satellite, and I've run into a problem. Assuming a 400km circular starting orbit(and disregarding ...
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Forces experienced during transfer orbit
As I understand it, astronauts are weightless because they are in constant free fall around the earth. To get from earth to the moon or earth to mars, spaceships execute a transfer orbit, where they ...
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Why is Wikipedia's delta-v from the Moon to Mars transfer so much lower than mine?
I tried to write a nice answer to this first question by a new user, but I've crashed and burned.
I calculated the escape from the Moon to be about 2,376 m/s which is close to 2.3 km/s shown in the ...
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Do "partial" Hohmann transfers exist?
I'm doing some research for fiction writing, and I would like to have my plot points comply with known science whenever possible.
Regarding orbital transfers, I know that the fastest way from orbit A ...
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Do satellites inject into a Hohmann transfer orbit in Low Earth Orbit or in Solar orbit?
Lets say we have a satellite wanting to go to Mars. Do satellites such as MAVEN inject into a Hohmann transfer orbit while in Earth's orbit, or do they go out of Earth's Sphere of Influence into solar ...
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Why is the Chandrayaan lunar insertion so long?
The Chandrayan take 5 earth orbit modifications to reach a translunar trajectory. I thought less orbit modifications should be enough:
orbit inclination modification
burns to go into a ...
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What is Buzz Aldrin's T.O.R. plan? How does it work?
Buzz Aldrin is recently quoted in Ars Technical's Buzz Aldrin is looking forward, not back—and he has a plan to bring NASA along:
“This T.O.R. plan may be the most important thing I’ve ever done in ...
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Getting from LEO to a station in geostationary orbit and docking with it using a Hohmann transfer?
How long would it take for a spacecraft with a mass of 30,000 kg, to go from LEO to reach and match the speed of a space station in geostationary orbit so it could dock with the station, using a ...
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How to find the transfer orbit from a initial circular orbit to a final elliptical orbit
Is a hohmann transfer or bi-elliptical transfer more efficient for this case? How can I find the transfer orbit that conserves the most deltaV?
I will be going from a circular Earth centered orbit ...
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Would a Hohmann transfer within LEO be useful?
Hohmann transfer is often used between a lower LEO orbit and MEO, GTO, GEO or beyond.
But if the target is a high altitude within LEO, how would a direct ascent compare to ascent to a lower orbit ...
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Ratio of low-thrust slow spiral to Hohmann transfer $\Delta V$?
Going from one circular orbit to another, there are tables out there and equations that give the total $\Delta V$ needed for a two or three impulse maneuver scenario.
For a very low thrust propulsion ...
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Hohmann transfer trajectory and "porkchop plot"
The “porkchop plot” for a spacecraft flying from Earth to Mars would show contours of equal characteristic energy against combinations of launch date and arrival date. Assuming the spacecraft has ...
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Quantitatively, how deep are the stable equilibrium points in GEO? How much delta-v needed to move from one to the other?
This answer discusses a spacecraft in GEO using a two-impulse (circular → elliptical → circular) raise & lower maneuver to move (phase) itself by 180 degrees in longitude then return to synchrony. ...
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Is it possible to supply 47 tons of payload to the orbit with 5 tons of fuel?
There are 2 orbits:
Circular orbit with 200km altitude
Circular orbit with 800km altitude
The space tug is already on the first orbit. Its dry mass is 960kg, the total mass of fuel is 5250 kg.
It ...
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Is Hohmann transfer the most frequent transfer orbit?
I have to complete a project for a university exam. The task is to design an interplanetary trajectory from Earth to Saturn, and to compare it with a
Hohmann transfer to the same planet. I also have ...
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Why is a Hohmann transfer from an elliptical orbit to a circular one more efficient if done from Perigee?
I was doing some calculations, mainly a Hohmann transfer between the following two orbits...
Note my calculations assume 0 perigee argument, 0 inclination and 0 right ascension...
Orbit start (400 ...
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Best heading for Hohmann transfer in real life
Assuming one wants to go from a 400x800 to a 1000x1000 orbit.
The solution that require the least D/v is a Hohmann transfer, with one burn at the perigee and one burn at the new apogee (or vice versa)...
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How to intuitively explain that tri-elliptic transfers are not better than bi-elliptic transfers?
The question How to intuitively explain that reaching geostationary orbits consume more Delta V than escape orbits? includes the graphic below, which illustrates that when transferring between ...
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How to intuitively explain that reaching geostationary orbits consume more Delta V than escape orbits?
Studying again orbital maneuvers, I found the following plotting the cost of a Hohmman transfer between coplanar circular orbits (black line), in terms of $\Delta V$ against the orbit ratio $r_f/r_i$.
...
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Mars transfer window frequency
According to this website I drew up a timeline of Mars transfer windows and the time you'd need to stay on Mars before the next return window:
Blue to red arrows are Earth to mars transitions, red ...
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How to calculate mass of fuel for Venus Orbiter
I'm working on a hypothetical constellation of orbiters at Venus for a school project, and I am currently trying to figure out how much fuel I need in the transfer stage. I have already calculated ...
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How do I calculate wait time to launch?
I want to transfer between two planets using Hohmann transfers and the patched conic approach. However, I am struggling to figure out how long I have to wait at the starting planet (say Uranus) until ...
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Would a Mars flyby be possible on a transfer orbit from Saturn's moon of Titan to Earth?
So, I am trying to calculate whether a transfer burn from Saturn's moon of Titan to Earth would involve a Mars flyby, assuming I have the burn start on 2 March, 2025 and arrival on 19 March, 2031. ...
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What's the reasonable "window" in days for a Mars-Earth Hohmann transfer?
As any popular science reader knows, when traveling between Earth and Mars, there's a Hohmann transfer opportunity about every two years (I believe it's every 26 months, specifically).
What I've ...
