Questions tagged [orbit]
Questions regarding an object 'falling around' another object, due to a combination of gravity and momentum.
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Period between when a point on earth’s surface intersects its orbit
Is there a name for the period between when a point on earth’s surface crosses/intersects its (the earth’s) orbital path and crosses it again the next ‘day’?
It would be almost, but not, be the same ...
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Calculating the altitude of a satellite in polar orbit for a given distance between successive ground tracks
I'm working through Orbital Mechanics for Engineering Students - Curtis (first edition). Problem 2.7 on page 101 is as follows:
It is desired to place a satellite in earth polar orbit such that ...
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Do extra-solar planetary systems tend to have higher eccentricity than our own?
I was sent here from hsm.stackexchange (see https://hsm.stackexchange.com/questions/19091/what-is-the-history-of-circularization-theories) when I asked about the history of circularization of orbits. ...
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Will the center of the Milky Way ever be above the Northern sky?
Today, the center of the Milky Way is generally visible above Earth's southern hemisphere. As our solar system orbits the galactic center, will this change in about 100 million years to become visible ...
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Where are the foci of Earth's orbit?
The following is a figure from a textbook, it depicts the Earth's orbit in space.
I added the red annotations for the sake of this question.
I know that according Kepler/Newton the orbit is an ellipse ...
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S2 orbit - orientation relative to our line of sight
S2 is probably the most observed among the S-stars that orbit around the black hole at the centre of our galaxy.
I'm trying to understand S2 orbit orientation but I'm having hard time with (I suspect) ...
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What would the shadow path of a geostationary object be?
If we managed to put an object into geostationary orbit over the Earth that was large enough to cast a noticeable shadow on the ground, what path would that shadow take? I’m wondering both about the ...
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How would Earth's orbit change if the Sun lost 1% of its mass per century?
The Sun naturally loses mass over time through radiation and the solar wind, but this occurs at a very slow rate. Hypothetically, if the Sun’s mass loss were accelerated to 1% per century (whether by ...
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When will Earth be in perihelion in the year 3088?
I tried to use JPL Horizons and came up with the 9. January but another Source
gave more like 21. January.
I need the exact date for some private research. Can someone post it maybe with a Graphic ?
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Could the galactic tide play a significant role in generating hyperbolic comets?
It is known that the galactic tide plays a role in sending Oort cloud objects toward the inner solar system by decreasing their perihelia. Recently, this question was asked regarding the ...
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Where is earth located after 2 years in relation to Mars assuming perfect circle orbit and at the start both planets are aligned?
According to Copernicus the assumption was that the planets orbit in perfect circles. Based on that his model was created. I was reading about this and I am confused on the following:
The earth moves ...
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Calculate approx date that sun's altitude is 60 degrees at a given latitude
I was reading some sort of exercise which asks the following:
If the altitude of the pole star at X location is 53 degrees and
considering that the sun rose earlier the previous day what is the
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Why is this Horizons query suggesting a different date/time for Earth's minimum heliographic latitude than SunPy's get_earth()?
When I use Horizons to check this by setting the target body to Earth (body center) and the observer to Sun (body center), checking times from 2025-03-06 to 2025-03-08 every minute, and setting the ...
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Does the Moon fall to the Earth, but always misses?
You can often hear this explanation for why the Moon (and other satellites) stays in orbit: it falls to the Earth, but always misses.
Is that a correct explanation?
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Why on the March 20, 2025 equinox does the sun rise due east at the equator but increasingly northerly as an observer travels north?
My source is the Suncalc.org calculator. Assuming the calculator is correct, then during the equinox and at the equator, the sun rises and sets due east and due west respectively. When one moves north ...
