Stack Exchange Network

Stack Exchange network consists of 174 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [frame-of-reference]

The tag has no usage guidance.

2
votes
0answers
33 views

How to compare the observation with the theoretically predicted result?

On the Wikipedia Article on “Geodesics in general relativity”, it says the following: “Thus, for example, the path of a planet orbiting a star is the projection of a geodesic of the curved 4-D ...
2
votes
2answers
64 views

Calculate position of the Sun in ECEF

I'm making a very basic orbit simulator in C# using the Helix Toolkit. I want to position the Helix lighting object at the sun, but also be able to calculate solar eclipse by the moon and earth for a ...
3
votes
0answers
23 views

Does Celestia respect 'setframe' coordinate systems?

Through trial and error (see script below that summarizes what I've found), I've learned Celestia's coordinate system appears to be: The x axis points to the vernal equinox The y axis points to the ...
1
vote
1answer
580 views

ECEF to ECI conversion

How to perform the conversion of (r,v) vector from ECEF to ECI (J2000) coordinate frame? What I tried I multiplied the matrix ([cosA -sinA 0] [sinA cosA 0] [0 0 1]) by the state vector, where A is ...
1
vote
1answer
77 views

How does the ITRS frame related to ECEF frame?

How does the International Terrestrial Reference frame related to the Earth-centered, Earth-fixed frame, as both of them rotate with the Earth?
2
votes
1answer
86 views

Reference frames in relativity?

I've recently been introduced to relativistic celestial Reference Systems (RS) such as the Geocentric Celestial Reference System (GCRS) and Barycentric Celestial Reference Systems (BCRS). So, for ...
1
vote
1answer
117 views

What are the reasons for referring to equinox J2000 or the equinox of the date?

(Background: Trying to learn something about the mathematical and computational part of astronomy I have acquired a copy of Meeus' "Astronomical Algorithms" and implemented the material up to Chapter ...
5
votes
1answer
119 views

Which rotational frame does the universe prefer?

Which rotational frame does the universe prefer? We say that the earth rotates once per 24 hours. But is this the master frame? What is the solution to Newtons Bucket Problem? I would like if the ...
2
votes
1answer
99 views

What's the difference between GSR and Grf

I note there are two terms about Galactic rest frame in literatures: Galactic Standard of Rest (GSR) and Galactic Rest Frame (Grf). Are they the same frame? If not, what's the difference?
1
vote
1answer
43 views

Has celestial navigation been materially impacted by the imperfect nature of celestial reference frames over time?

In this video on inertial reference frames, it is mentioned that the stars are humanity's best inertial reference frame: the earth experiences a subtle acceleration relative to the sun due to the ...
5
votes
1answer
720 views

Conversion between Astronomical Frames, ex. IRCF, FK5, FK4, etc…

I'm a little bit confused about reference frames, and I was wondering if someone could help clarify a few things? So let's say I have equatorial coordinates that refer to the mean equator and equinox ...
8
votes
1answer
853 views

How can one explain the apparent motion of the Sun from a heliocentric point of view?

From a horizontal frame of reference, the path of the Sun looks like a part of a circle in a tilted plane, as shown in this picture:            &...