Tagged Questions

Questions regarding an object orbiting around another object due to the force of gravity.

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Do differentials in the Earth's density cause the flyby anomaly?

The flyby anomaly is an occasional, unpredictable, and as yet unexplained discrepancy in acceleration of satellites when they pass close by the Earth. It causes an increase of up to 13 mm/s during ...
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How to understand orbit definitions

I've been reading about satellite observations (such as this one). The writer uses terms such as these to define the orbit: ...
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Directly calculating lat/lon of a satellite directly from RA/declination

I have RA/declination values of a satellite and the observer's location in terms of lat/lon. I want to convert the values for satellite into lat/lon. I have tried to use the method which uses ...
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Which frequency should be used to communicate with a cube satellite?

I am trying to build a cube satellite using a raspberry Pi. I am trying to figure out which radio frequency could be used to communicate with the cube sat to transfer data like images, videos, ...
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Polar satellites for Global Navigation Systems

Why do we need 7 polar satellites for a navigation system like the Indian Regional Navigation Satellite System (IRNSS)?
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Unknown moving objects

Last night, I used my new Sony WX500 camera to get long exposure pictures of the sky from my backyard. I used the "Heavens Above" app to find out when satellite flares would happen and I even got a ...
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Magnitude, satellite flare and the Heavens Above app

On the Heavens above app for Android and maybe iOS, it shows negative magnitude values for Iridium satellites, but for other ones, it shows positive. Here is a screenshot Why is this?
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Tools and algorithms for angles-only orbit estimation

I've seen discussion threads where amateur astronomers estimate a satellite's orbital parameters from angles-only telescope observation. Are there any community tools or algorithms to help with this ...
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Terminology: Is there a name for the points on the surfaces of tidally locked parent/satellite bodies that always face each other?

This is purely a question about terminology, one that has eluded my googling efforts. When a satellite and its parent body are tidally locked to each other, there is (in an ideal case) a single ...
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What were the 2 satellites I saw this morning?

This morning at 6:03am Israel time (3:03 UTC) I saw, simultaneously, what appeared to be 2 satellites streaking across the sky directly overhead. If I remember correctly, they were both coming from NW ...
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How many satellites orbit the Earth? At what rate do they orbit the earth? [closed]

I was looking at a full moon the other night with my telescope and noticed a black dot move across the moon quite rapidly. This happened a few times and others who were with me were able to confirm. ...
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What is the detector size of LANDSAT 8's detector array?

According to the suggested tags, this must be the right forum: I found that for each band of Landsat 8 over 7000 detectors are on the array. Does anyone know how big each of the sensors is?
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The dark side of the moon [duplicate]

I encountered this statement that the dark side of the moon is hidden from our sights. Could someone please explain?
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How can exoplanet moons be detected? [duplicate]

How can exoplanet moons be detected? Are there current methods to differentiate exoplanets with moons and exoplanets without moons? Or, are only the combined masses of the exoplanet and its moons ...
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Why do some artificial satellites decrease and increase in brightness multiple times?

I just observed a satellite almost directly above me travel for a few minutes while constantly dimming and then getting brighter. It did this for about 3 minutes until it faded out. I also observed a ...
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what is a MIA satellite

I came across this sentence in a magazine: We sit outside the Lorne Community Hall, Victoria, watching the MIA satellite overhead. I wonder if the author is talking about an artificial satellite....
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What is the difference between Sphere of Influence and Hill sphere?

Wikipedia's definition of Hill sphere is: An astronomical body's Hill sphere is the region in which it dominates the attraction of satellites. To be retained by a planet, a moon must have an orbit ...
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Are multiple satellites required to handle geostationary orbits?

Do geostationary satellites need to have the equator as the plane of rotation, and the earth's centre to be the centre of rotation? Can it rotate over, say, the Tropic of Cancer, focusing on a single ...
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Are ascending node of sun, the point of intersection of prime meridian and equator and center of earth all collinear?

I did a bit of googling but couldn't find the exact answer, so are the following 3 points collinear or not ? 1_center of earth 2_ascending(or descending) node of sun 3_point of intersection of ...
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Derivation of the formula for longitude of ascending node for a satellite

I've been looking into the document IS-GPS-200H to understand how to calculate satellite location in the ECEF coordinate. I am having problem understanding the formula to derive $\Omega$, the ...