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When was Newton "not good enough" for spaceflight; first use and first absolute requirement for relativistic corrections?

Concepts in Special Relativity (1905) and of General relativity (first developed between 1907 and 1915) substantially predated spaceflight; they were well known and had been tested well before objects ...
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Is the zero gravity experienced in ISS the "artificial" kind?

I always wondered about the following: An astronaut floating inside a spaceship that is far from Earth or any other other planet will experience true zero gravity because there is negligible ...
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Why are Tiangong-1's Apogee and Perigee Graphs Wobbly?

The apogee and perigee graph of the Tiangong-1 space station, about to re-enter and break up Real Soon Now, is depicted in this graph (source: Wikipedia): Why are the graphs wobbly? Is it because the ...
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698 views

Did the spacecrafts Galileo or Juno use the Galilean moons for a gravity assist before entering Jovian orbit?

Galileo and Juno are the only two spacecraft to have entered orbit around Jupiter. Did either of them use one of the Galilean moons for a gravity brake before in order to enter a stable orbit around ...
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Python Libraries: Numerical Propagators and Access Calculations

I have written some of my own code in Matlab that performs two body unperturbed as well as J2 perturbed orbit propagation. I am shifting to a new environment that requires the use of Python, and can't ...
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How to determine an algorithm for Low Earth Orbit propagation, considering perturbation from the moon, sun, etc?

I'm trying to determine an algorithm for orbit propagation for a satellite on LEO, with high accuracy in a six month time ...
724 views

Besides retarded gravitation, anything else to worry about when calculating MU69's orbit from scratch?

For fun I'd like to use Hubble Astrometric data for example the observations listed at the bottom here to numerically estimate the orbit of 2014 MU69 as well as its uncertainties. My plan is to use ...
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362 views

Do Curiosity's reported measurements of Mars' surface gravity (~3.717 m/s^2) include centrifugal effects?

In this answer I discuss the first results in the 47th Lunar and Planetary Science Conference (2016) conference paper First Gravity Traverse on the Martian Surface from the Curiosity Rover and a more ...
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Calculating the planets and moons based on Newtons's gravitational force

I am trying to understand how to calculate the orbits of solar system bodies in an n-body framework, based on the pair-wise gravitational interaction between the objects. At present, I am considering ...
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424 views

RIP Kepler, how shall we call your orbit? Does this cyclic flip-flop process have a name?

So long, and thanks for all the Fish Planets The captions in the NASA Ames Research Center video What Will Happen to NASA’s Kepler Spacecraft? read as follows: NASA’s Kepler space telescope found ...
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526 views

Does NASA use Newtonian model of gravity for plotting the course of Juno or general relativity?

With the huge mass of Jupiter and its fast, approximately 10 hours daily rotation, there may be substantial twisting of space-time around it. A distortion of such magnitude that may call for ...
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536 views

Delta-v obtained from Titan by the Cassini spacecraft; just how much of a "gas tank" was it?

In the video Cassini at Titan: A World Unveiled after about 01:56 Linda Spilker, Cassini Project Scientist, Jet Propulsion Laboratory says: Not only was Titan ...
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338 views

Calculating spacecraft thrust manoeuvres with JPL data

I've recently programmed an animated simulation of the main elements (core planets and Sun) of our solar system: by using the initial coordinates from the JPL (Jet Propulsion Laboratory - NASA) ...
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403 views

How to calculate the very special orbit of 2020 SO

From a NASA JPL page: Earth May Have Captured a 1960s-Era Rocket Booster Source (Sorry, I got an error when I tried to include an animated gif.) 2020 SO was captured by Earth's gravity on Nov. 8, ...
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