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1 vote

How to estimate perturbations from other planets in Apsidal Precession

I don't think that perturbations by other planets will lead to an apsidal precession as such. Apsidal precession is due to the gravitational potential having a consistently stronger or weaker radial ...
Thomas's user avatar
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5 votes
Accepted

Relative inclination with respect to line of sight

Hard to follow your query. Maybe if you labelled $i_{\rm star}$ and $i_{\rm LOS}$. The inclination angle is defined in exactly the way you show - but the diagram is not unique. Perhaps the source of ...
ProfRob's user avatar
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10 votes
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Can an astronomer fully work remotely?

This might be more a question for Academia.SE, but: I have tried this during two different fellowships, and while it did work out, I cannot recommend it. Due to family reasons, I stayed in my home ...
pela's user avatar
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5 votes
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How long would a day be in an earth like - same size and all - planet but with double earth's orbit in time

The time for a planet's revolution (orbit) is completely unrelated to the time for its rotation (spin). There's no connection between the length of a day and the length of a year on any given body. ...
Darth Pseudonym's user avatar
1 vote

How long would a day be in an earth like - same size and all - planet but with double earth's orbit in time

The length of a day can be almost any number. For example, Mars' days are just slightly longer than Earth's. The planets beyond Mars have faster rotation rates. Its orbit would be somewhat beyond Mars....
stretch's user avatar
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2 votes

How long would a day be in an earth like - same size and all - planet but with double earth's orbit in time

The Earth's rotation period has been slowed to some extent by the tidal influences of the Moon (principally) and the Sun. The Sun's tidal influence is much smaller than that of the Moon. Tidal torques ...
ProfRob's user avatar
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-7 votes

Is the gravitational constant really constant over our Universe?

One of the big problems with the gravitational constant is that its units are not dimensionless. And so one expects it to represent some physical quantity. What is that? Another problem is that ...
David's user avatar
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12 votes

Is the gravitational constant really constant over our Universe?

See also Do the laws of physics work everywhere in the universe? on the Physics SE. If the gravitational constant were not constant, then the laws of physics work differently elsewhere in the universe....
Allure's user avatar
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4 votes

Is the gravitational constant really constant over our Universe?

Within General Relativity (GR), the gravitational constant $G$ is postulated to be a fundamental constant having the same value over our Universe. Within the Brans-Dicke theory, which is a competitor ...
Michael_1812's user avatar
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2 votes

Do all black holes, including stellar-mass ones, rotate at nearly the speed of light? Also, what exactly does that do to their shape?

The maximum angular momentum, $J$, for a spinning black hole is given by $$ J \leq \frac{GM^2}{c}\ . $$ This corresponds to a maximally spinning black hole having a "spin speed" of $\leq c$ ...
ProfRob's user avatar
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2 votes

Earth-Moon receding-approaching cycle?

"I got an answer by an astrophysicist where he said that in reality what would happen is that the Moon will recede up to the point where the orbit would be unstable and chaotic and therefore 3 ...
Michael_1812's user avatar
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