Questions tagged [delta-v]

Literal meaning is "change in velocity". The quantity has utility in rocketry as measure of the change in velocity that a reaction engine must produce to move into a given trajectory. The rocket equation establishes that the mass ratio of payload to initial mass is an exponential function of delta-v divided by the propellant velocity.

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What would it take to bring VSS Unity over the Kármán line?

There's been a great deal debate about Virgin Galactic calling 50 miles "space", while most use a 100 km Kármán line definition for the term. VSS Unity has exceeded 89 km altitude on two ...
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Has there ever been a completely solid fuelled orbital rocket? [duplicate]

Engines and fuel management are very expensive to develop, and for smaller launch providers and space agencies this could prevent them from entering the market. My question is, would the cost savings ...
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Calculating the delta V budget from Earth to Mercury

Context While verifying a basic computation to compute the required delta V budget to get to Mercury I am experiencing some difficulties in interpreting the number 8650 m/s from Earth intercept to ...
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Specific impulse and delta-v in Tsiolkovsky's rocket equation

According to Tsiolkovsky's rocket equation, it is possible to calculate the delta-v of a multistage rocket if you know the characteristics of each stage of the rocket. In my case, the only ...
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How much delta-v does it take to go from one arbitrary orbit to another?

This is, in theory, very basic rocket science. I can't seem to find a solution on here though, so I'm asking in the hopes you'll enlighten me and my amateurish ways. I've got a set of Keplerian ...
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What are the limitations to using this “trick” to quantitatively relate altitude changes (via their speed) with applied forces that cause them?

In this comment I used a "trick" to double check a calculation in the post above it. Using the vis-viva equation I first determined that if the ISS lost 10 meters of altitude in 86400 ...
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Earth-Sun decayed L1 to L4 transfer

Assume CR3BP (Circular Restricted 3-Body Problem) where a satellite occupies the Earth-Sun L1 point. The satellite dies, stops station-keeping, experiences a small perturbation (minimal effect on ...
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Computing a new TLE following a delta-v impulse?

Is there some code or a library out there that can take orbital elements, add a known delta-v component and then compute a new TLE? I found this one https://apps.dtic.mil/dtic/tr/fulltext/u2/a289281....
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Largest single burn spacecraft delta-v in deep space?

This 700 m/s maneuver that was avoided got me thinking and then CNN's NASA mission will zoom by asteroid before returning sample to Earth said: "Leaving Bennu's vicinity in May puts us in the '...
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Minimum delta V required to return a piece of metallic asteroid 16 Psyche to Earth?

Suppose somebody sent a rover to Psyche 16 and found massive concentrated deposits of platinum-group metals near the surface, and turned it into a 10 ton sphere of platinum/iridium/osmium/gold alloy ...
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With C3 = 16 km²/sec², How much ∆V is required for the probe to enter a Mars orbit with periapsis at 100 km and Apoapsis at 1000 km?

A Mars probe leaves earth with a Characteristic energy (C3) of 16 km²/sec². How much ∆V is required for the probe to enter a Mars orbit with periapsis at 100 km and Apoapsis at 1000 km?
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Why does it cost more to get to L4/5 than C3=0?

I was looking at Delta-V budgets and noticed that it costs 4.1 km/s to get from LEO to L4/5, but just 3.2 km/s for LEO to geocentric C3 = 0 (escape velocity). I find that counter-intuitive. Why does ...
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Is Delta V depending on the Launch Vehicle mass and the Payload Mass?

I have read in many references that Delta V is fixed or constant for example ( Delta V to LEO = 10km/s). They did not mention the payload mass or the Propellant mass, and also they did not mention ...
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Does a fully fuelled Starship in LEO have 0kg payload to Jupiter?

So I was looking into the payload mass a fully fuelled Centaur V could send to Jupiter and used the formula in presented in this answer to create a C3 graph. For a bit of fun I also looked into the ...
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Do rockets headed to ISS get delta V benefit from Earth's rotation

A rocket on the launchpad moves Eastward with the rest of the earth as it rotates about its polar axis. This means that on launch, the rocket already has a sizable eastward velocity component: ~460 m/...
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Station-keeping delta-v per year for an Earth-Moon vanilla halo orbit?

This answer reminds us that an Earth-Moon L1 or L2 vanilla1 halo orbit remaining always visible to some patch on the Moon's surface requires station-keeping. Queqiao uses such an orbit having ...
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General Delta V Calculation for Two-Body-Problem

Problem: Given two orbits (e.g. in the 5 keplerian elements excluding true anomaly) A and B calculate the $\Delta v$ necessary to perform a transfer from A to B using instantaneous burns. Simple ...
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How to determine the delta V required in order for the satellite at pt. A to hit the earth at pt. B?

I'm confused about how would I go about obtaining delta-v in this case. I'm aware of orbital transfers such as bi-elliptical but that is not the answer to this. Kindly help
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How exactly do “commanded delta-v burns” work in practice? (e.g. OSIRIS-REx)

Reading this answer to Could the uncertain mass of the OSIRIS-REx sample affect the trajectory of the return capsule? I infer that traditionally deep space spacecraft are sent timed commands for burns ...
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How much delta-v have I used here? What's the “official” equation for delta-v from parametric thrust?

I took a break from Stack Exchange, jumped in my spacecar and flew the following squiggle: $$a_x = \cos(10 \ t)$$ $$a_y = \sin(5 \ t)$$ $$a_z = \cos(2 \ t)$$ starting at ...
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Why is “delta-v + $\sqrt{{v_E}^2 + C_3}$ where ${v_E}^2 = $11.19 km/s” the correct way to calculate total propulsive delta-v? Please show all work

There is one answer to What spacecraft has had the greatest total propulsive delta-v? and I can not understand how its numbers have been calculated. Response to comments does not seem forthcoming so I'...
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What spacecraft has had the greatest total propulsive delta-v?

How fast is fuel escaping a rocket for it to reach the escape velocity 11 km/s? was an active and well-received discussion! It's always exciting when we first realize that a rocket can go much faster ...
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Range of travel time between particular planets using the Interplanetary Transport Network/Interplanetary Superhighway?

I understand the Interplanetary Transport Network allows for travel at low speeds between different planets in the solar system using very little energy. Is there flexibility in how long it would take ...
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Do lower pressure pressure-fed rockets get more Delta-V?

I was playing around with the math for getting a pressure-fed rocket to orbit and came across something that I haven't seen addressed anywhere. In a pressure-fed rocket, the chamber pressure of the ...
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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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Why is it easier to escape the solar system than get to Mercury or the Sun?

It has been mentioned several times on this site that it is "easier" (less delta-v, and hence less fuel) to reach the escape velocity of the solar system, than to reach the planet Mercury or ...
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Effect of incoming velocity on change in velocity in a gravity assist

In a gravity assist does the incoming velocity of a space craft effect how much speed it gains. For example say a rocket was approaching Jupiter for a gravity assist with speed v and another rocket ...
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Delta-v difference between Mars and Moon

Considering a simple Hohmann transfer, does it take less Delta-v and propellant to go to Mars than to the Moon
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Increase in period and semi-major axis following near head-on collision between Cerise and Ariane debris (1996)

This report describes the collision of the French satellite Cerise with a piece of Ariane rocket debris (object no. 18208) in 1996: http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?...
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What does a typical delta-v budget look like for a LEO satellite?

In terms of launch, initial orbit correction, stationkeeping, deorbiting, etc. for a typical 100-200 kg LEO satellite? Is there any source online with specifications for non-private Earth-orbiting ...
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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 any modern launch vehicle have put Ulysses in it's polar heliocentric without going to another planet first?

This answer to Why aren't satellites launched into a Polar LEO to get into Polar Heliocentric Orbit? leaves me wondering if it could be done today without the trip to Jupiter. Could a replica of the ...
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How much delta-v does the Orion spacecraft have?

Orion is intended to transport astronauts around cis-lunar space. How much delta-v performance does it actually have?
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Delta V/Fuel Cost for Satellite Rotation

How would you figure out the fuel cost or delta V for spinning up a S/C to match the orbital period of 27.32 days (moon orbit)? Given that the S/C is initially not rotating about any axes. For ...
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How much delta-v does it take to get from a Lunar Transfer Orbit to a Near Rectilinear Halo Orbit around the moon

There has been a lot of talk of NASA putting a Lunar Gateway in a Near Rectilinear Halo orbit around the moon, but I don't actually know how much delta-v it takes to get there. Most delta-v maps I can ...
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Do you need 0 km/s velocity to crash into the sun?

I was reading a popular thread about the delta-v required to escape the solar system compared to the delta-v required to crash into the sun. I get it: the earth itself already has a high speed (29.7km/...
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How to change RAAN with 250 m/s DV?

I'm performing a transfer between 2 orbits with different RAAN (other orbital parameters are same). The perigee altitude of the orbits is 1000km, the apogee is <...
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Will crewed vehicles ever follow multi-flyby trajectories?

A while ago, I asked a similar question here, but I think it was confusing, so nobody answered. Two questions: This one is a bit subjective: Do you think that lengthy (+5y) multi-flyby trajectories ...
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Delta-v for landing on the moon

I'm doing a few calculations to understand how to go from the Earth to the Moon. I used an elliptical (Hohmann Transfer) orbit to go from LEO to a circular Moon's orbit performing two $\Delta v$ (...
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How do you calculate the percentage of light-speed a ship with a certain delta-v can achieve, accounting for relativistic effects?

I was doing some back-of-a-postage-stamp calculations on high-isp interstellar spacecraft earlier and realised something. If I design a spaceship which according to the rocket equation has a very high ...
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What is the delta-v required to reach Titan (Saturn's moon)

How much speed do I need to put something to orbit on Titan? I know it is a simple question but look among those maps that are there but they are not clear to me.
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What would the rocket equation look like for 4 ion thrusters?

If i have 4 ion thrusters(IFM Nano Thrusters), how would the rocket equation have to be done to calculate the total delta-v?
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How to calculate delta v for orbit change around body; not necessarily Earth?

Let me express my joy at having found this great place of Stack Exchange. My question concerns the calculation of delta v requirements when already in orbit around a body and lowering or raising ...
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What would be the best course of orbital maneuvers for soft landing an asteroid near the lunar south pole? [duplicate]

Wouldn't it be nice for a colony near the south pole of our Moon to have a nickel-iron asteroid on the surface nearby ! Thousands near-Earth asteroids (NEAs) have been discovered with a diameter up to ...
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When is it okay or at least helpful to use energy arguments in orbital mechanics?

When faced with energy-based questions about spaceflight we often comment something like orbits are about momentum, not energy and use delta-v math in answers. But in this answer to How big a nuke ...
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What is delta-v calculated in reference to?

I understand delta-v is literally just the potential change in velocity, but this would obviously differ between air resistance, gravity and many other factors, so what is delta-v calculated in ...
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How to use specific impulse for multiple stages

I am given a scenario where I need to create a program to give the initial launch mass of a spacecraft that can vary between 4 and 20 stages. I am given that the "specific impulse for all stages is ...
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Can a Mars orbiter mass only 50 kg?

A press release by the SatRevolution consortium says that it plans to send cubesats "as small as 50 kg" to Mars to "conduct a variety of valuable science." So that means orbiting, not just a flyby ...
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Launch to orbit delta-v penalty from Venus compared to Earth?

Thinking about the no atmosphere caveat here made me think of Venus, which is the opposite of no atmosphere for solid/rocky bodies in our solar system. Earth's low orbital velocity is about 7.8 km/s. ...
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Trivial lower bounds for single point mass delta-v problems?

Given two arbitrary elliptic orbits around an ideal single point mass, there will always exist a transfer with the minimal $\Delta v$ required. It's easy to find an upper bound for this ideal transfer:...