Questions tagged [orbital-mechanics]
Orbital mechanics (also called astrodynamics) is the application of ballistics and celestial mechanics to the practical problems concerning the motion of rockets and other spacecraft on an orbital or escape trajectory. For the movements of celestial bodies, use [celestial-mechanics], not this.
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Why should space probes have to orbit the Earth before being launched at other planets?
I'm curious to know why any satellites that need to be sent to other planets should be moving around the Earth rather than directly going towards their destination? Today, India launched one satellite ...
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2D Orbital Path from State Vectors
Given a planet of mass $M$ at the origin, and the state vectors $\textbf{r}$ (in meters) and $\textbf{v}$ (in $m/s$) at time $t = 0$ for a satellite, what are are the equations for:
Distance $d(t)$ ...
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At which point would two GSO/GEO satellites with similar orbital elements be closest to each other?
While I was answering another question on How closely spaced are satellites at GEO I came to realize I can't really word it with much conviction how two close proximity satellites in GEO/GSO orbits ...
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Why did the rendezvous attempt fail on Gemini 4?
It is said in Wikipedia, that
On the first orbit, McDivitt attempted to rendezvous with the spent
Titan second stage. This was unsuccessful for a number of reasons:
NASA engineers had not ...
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How did NASA determine the distance and velocity of voyager 1?
According to Wikipedia
At a distance of about 125.97 AU (1.884 × 10$^{10}$ km) from the Sun as of September 9, 2012, it is the farthest manmade object from Earth
As of 2013, the probe was moving ...
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How can I figure out the distance to Juno at any point in time?
Juno will fly by Earth on October 9, 2013. There is an event to encourage Amateur Radio Operators to say high to the satellite. What I'm trying to do is figure out if I have any chance of pulling it ...
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When could MAVEN launch to get to Mars, if it misses its launch date?
What kind of transfer orbit will MAVEN follow?
If it is a Hohmann Transfer Orbit which will be effective only when the launch point and destination of spacecraft are in straight line. Earth is its ...
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Does a mission to Venus orbit require less propellant than a similar mission to Mars?
Gravitational attraction is determined using G (m1m2)/r^2
Which indicates the force is inversely proportional to the square of separation of the bodies
Of the terrestrial planets Mercury, Venus, ...
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Delta-V chart mathematics
Could someone explain me the mathematics behind the Delta-V charts one can find on internet such as:
&...
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How does the gravity of a massive non-spherical object act on things around it?
Firstly, not sure if this question ought to be in the physics SE site. Please let me know if it should.
Secondly, I don't know a whole lot about physics (I'm just inquisitive). So please try to keep ...
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Is LOI usually performed on the far side of Luna?
Wikipedia writes to say
Once the spacecraft reached the far side of the Moon, its rocket motor was fired in order for it to be captured by the Moon's gravity into an elliptical lunar orbit.[27]
I ...
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How to programmatically calculate orbital elements using position/velocity vectors?
I would like to build some orbital mechanical software from scratch. I feel that this would be a great way to learn the steps required to calculate different Kepler orbital elements of an object, plot ...
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Is an orbital epoch merely a timestamp?
Just what the title states please. This site writes to say
Orbit epoch is the time at which the established orbital elements are true
The site goes on to mention sub-elements -
Start Day The ...
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Is there any reason to send space probes along the plane of our solar system instead of perpendicular to the plane of our solar system? [duplicate]
Is there any reason to send deep space probes (Pioneer and Voyager) along the plane of our solar system (maybe with a slight inclination) instead of perpendicular to the plane of our solar system?
If ...
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Could Cassini crash land on Mercury?
I saw a news article once that discussed having Cassini use gravity assists to crash land on Mercury to end it's life. Is this even possible, and is there a chance that this could actually happen? Or ...
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How frequently do asteroids collide with each other?
Space is empty ... lots of empty. Apparently so empty that the risk of collision between a spacecraft of our times, and an asteroid in the asteroid belt is said to be infinitesimal.
Running a search ...
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Is there a table of the gravitational pull of a spacecraft? [duplicate]
I would like to put a spin on What is the maximum mass of a satellite that can be placed in GEO?
Gravity is a function of the mass of both (all) bodies, and their relative separation. Wikipedia lists ...
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How to calculate delta-v required for a planet-to-planet Hohmann transfer?
How do you calculate the delta-v required to do a Hohmann transfer from a circular orbit around one body to a circular orbit around another?
I'm assuming you'd need to know the masses of the two ...
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What is the maximum mass of a satellite that can be placed in GEO?
What is the maximum mass of a satellite that can be placed in GEO? Or can satellites of any mass be placed in GEO?
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Gravity drag Delta-v calculation for launches to orbit
It would appear that gravity drag has a exact formulation for an instantaneous moment in a rocket launch.
I'm tempted to think that some calculus could get you an exact number for Delta-v of an ...
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Is it theoretically possible to dispose of the larger pieces of space junk into the Sun?
Space junk is a real threat to working satellites in the Earth's orbit. Is it theoretically possible to make this space junk escape from the Earth's gravity (by giving them some kinetic energy to ...
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Why will JUICE take 8 years to reach Jupiter, longer than any earlier spacecraft?
Galileo took six years from Earth to Jupiter.
Cassini-Huygens took three years to reach Jupiter and six years to reach Saturn.
New Horizons took one year to reach Jupiter.
Juno was launched in 2011 ...
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Can communication satellites be used in lunar orbit?
Because the moon always has the same orientation to earth, if we want to have communications with manned or robotic explorers on the far side some type of relay would be needed for communication. ...
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Dreams of Tatooine doomed [closed]
Studies have shown that binary star systems doom any surrounding planets.
http://www.universetoday.com/71934/tight-binaries-are-death-stars-for-planets/
Does this mean that we will never be able to ...
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Are sun-synchronous orbits possible around any body?
Sun-synchronous orbits are popular around Earth, and the Mars Reconnaisance Orbiter uses one as well (so I think Wikipedias definition as a geocentric orbit is wrong). Considering that probably any ...
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Gravity assist for manned travel
Since we already use gravity assist to launch satellites through the solar system, is there any way we can use gravity assist to speed up a manned trip to a planet such as Titan or Europa, while also ...
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Could the sun be used as a gravity assist outside the solar system (with current tech)?
I think I might have understood what this XKCD comic is trying to do. The diagram is proposing to use the Oberth effect at closest approach to the sun to escape the solar system!
(image license: CC ...
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Preventing orbital decay and micro adjustments to orbits by "leaning" on Earth's magnetic field
Would it be possible, using current technology and renewable energy sources only (e.g. photovoltaics), to magnetically polarize external shields of orbiting satellites in such a way, to effectively ...
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Will Rosetta have to adjust its orbit around Chury due to the comet's coma and tails?
ESA's Rosetta spacecraft is scheduled to orbit 67P/Churyumov–Gerasimenko after it reaches the comet by mid-2014:
Rosetta's main objective is to rendezvous with, and enter orbit
around, comet 67P/...
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What is the probability of impact?
Space Track is a website dedicated to passing along information about satellites to consumers, primarily satellite operators. The information comes from the US military. In addition to providing the ...
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Did the ISS have to adjust its course when the SpaceX Dragon capsule was detached?
We had this question which discussed if space craft had to be corrected in their orbits from the movements from the people inside. (No as their net movement cancels each force out)
Following on from ...
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What are the choices today for orbital mechanics simulation software?
I used to be familiar with the various choices out there for orbital mechanics simulation software. Alas, those days are gone. What are the choices today, preferably sorted by platform?
This ...
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Do any launches bypass LEO?
If sending a payload to GEO (geosynchronous orbit) or any other high orbit, you could start off launching to LEO (low Earth orbit), and then use a Hohmann transfer to raise the height of the orbit. I ...
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How are flight plans calculated?
When a project like Rosetta is being developed, how are flight plans calculated? Do planners simply input the desired target into a program or a flight computer which spits out the optimum flight path ...
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Energy consumption for travelling to the Moon vs. to Mars
I just finished reading Clarke's "Prelude to Space". In chapter XXVII the character Taine gives a talk where he states
It sounds paradoxical, but it's easier to make the forty-million-mile journey ...
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What is the first non-solar-system object Voyager 1 will run into?
I know that the farthest man-made object from Earth is Voyager 1, and was wondering if and when it will ever come relatively close to another star system, or some other object located outside the ...
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Can a projectile fall into a low Earth orbit?
One of the problems with space flight is the speed required to achieve orbit; 17,500 mph. One of the ways I've always thought to achieve this was to launch at a low speed to a very high altitude then ...
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Can you tack against the sun using a solar sail?
Solar sails are a great, inexpensive way to move out from the sun, if you’re not in a hurry. Ocean going ships are able to tack against the wind, and to move up wind. Could a solar sail gain inbound (...
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Under what circumstances would an object falling out of spacecraft start orbiting that spacecraft?
In one of the short stories of Stanislaw Lem the main character, Ijon Tichy, accidentally drops off a piece of pork out of his spaceship, and this pork becomes a satellite of the spaceship, causing ...
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Why should the James Webb Space telescope stay in the unstable L2?
We all know that James Webb Space telescope is planned to be launched in 2018. It has been decided that the orbit of JWST will be elliptical around the Lagrange point L2, which has been declared as ...
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Could a partial space elevator be practical and useful?
Would it be technologically and economically practical to build and operate a space elevator that only provided transport between lower and higher orbital paths?
Such a mechanism would only avoid some ...
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How deep is the force well of L4 and L5 Lagrangian Points of Earth-Sun set?
The Lagrangian Points are points in space, where the combination of gravitational pull of a set of two bodies and the centripetal force of orbiting one of them add up to zero. The special property of $...
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How long does a CubeSat last?
If I were to launch a CubeSat, how long would it last before falling out of orbit and burning up in the atmosphere?
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What branches of mathematics are widely used in astrodynamics?
We knew that Voyager 1 and 2 exploited the gravitational slingshot from Saturn and Jupiter back in 70s, and the trajectories were predicted by Newton's laws of motion, and this law we used a lot in ...
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What creative orbital maneuvers might I do to save fuel for a geosynchronous spacecraft?
I've heard that there might be some creative ways to get to Geosynchronous Orbit that could save a lot of fuel. How might I manage to make this happen?
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