Questions tagged [satellites]
Satellite is a generic descriptor for any body that orbits a much larger body. The term commonly refers to objects orbiting planets, like artificial satellites and moons, but it can sometimes also refer to planets, small stars, satellite galaxies, and other objects.
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Is there a small enough planet or asteroid you can orbit by jumping?
I just had this idea of orbiting a planet just by jumping and then flying upon it on its orbit kind of like superman. So,
Would it be theoretically possible or is there a chance of that small body to ...
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Is it possible to have a geostationary satellite over the poles?
My understanding of orbital mechanics is very limited, but as I understand geostationary satellite, they stay in place by having an orbital speed corresponding to the spot they're orbiting over.
So ...
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Cooling a satellite
Satellites are isolated systems, the only way for it to transfer body heat to outer space is thermal radiation. There are solar panels, so there is continuous energy flow to inner system. No airflow ...
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Why is the period of a geostationary satellite not exactly 1440 minutes?
When reading about Astra satellites on Wikipedia (https://en.wikipedia.org/wiki/Astra_1KR), I saw that the period of the Astra 1KR satellite, positioned at 19.2° E, is 1,436.1 minutes (source: NORAD ...
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Why aren't satellites disintegrated even though they orbit earth within earth's Roche Limits?
I was wondering about the Roche limit and its effects on satellites.
Why aren't artificial satellites ripped apart by gravitational tidal forces of the earth?
I think it's due to the satellites being ...
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Cause of weightlessness [duplicate]
I'm a first year engineering student who is new to physics, so I apologize if my question is stupid. But in our statics course we are using the book "Engineering mechanics: statics" by R.C. Hibbeler ...
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How do we stabilise satellites so precisely?
Look at the Hubble Ultra Deep Field photo. The stars in it are on the order of 1 arcsecond across. To an order of magnitude, this is $10^{-6}$ radians in a $10\text m$ telescope which was held steady ...
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Why doesn't the Moon disrupt the orbits of geostationary satellites?
If a passing star can jostle comets in the Oort Cloud, why doesn't the Moon disrupt the orbits of high-flying satellites?
Or does it? Maybe the satellites need periodic course corrections?
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Why is Microgravity called "Microgravity"?
I find the term "microgravity" to be misleading, how was it coined?
NASA provide this definition:
Microgravity is the condition in which people or objects appear to be
weightless. The ...
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Build a ring around Earth, then remove the supports
What would happen if we decided to build a giant ring that managed to wrap around the whole world, end to end that was supported with pillars all along the ring and then the supports all suddenly ...
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Why don't we put satellites into an orbit where there is (almost) no time dilation/contraction compared to Earth's surface?
Consider:
On this image, if I understand correctly, the time dilation diagram is shown depending on the height for circular orbits. First in low orbit, time slows down relative to the surface due to ...
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Why are Saturn's rings so thin?
Take a look at this picture (from APOD https://apod.nasa.gov/apod/ap110308.html):
I presume that rocks within rings smash each other. Below the picture there is a note which says that Saturn's rings ...
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How large can planets or moons appear?
In many artistic impressions or movies there are pictures or scenes where the sky is filled with an enormous moon (as seen from a planet) or vice versa.
I wonder if there is an upper limit to the ...
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Are there any satellite orbit earth perpendicular to the sun and what is the name of this kind of orbit?
I think we could put satellite to orbit earth in such a way that it always see the sun. Which is orbiting along the path of earth orbiting the sun, like a wheel perpendicular to the sun
I don't know ...
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How does a satellite maintain circular orbit?
Given a crewed satellite placed at a distance $r$ from the center of the Earth, with an initial velocity perpendicular to its position vector, the magnitude of the initial velocity that would allow it ...
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