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Questions tagged [pyephem]

PyEphem provides the Python language with routines for computing the location of celestial objects like the sun, moon, and planets, as well as for any asteroids, comets, and earth satellites for which the caller can provide orbital elements. Rise, set, and transit times can be computed for any object, and basic coordinate computations are also supported.

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Difficulties with RA/Dec and Alt/Azi conversions with pyEphem

I'm trying to go from alt/azi to RA/Dec for a point on the sky at a fixed location, trying out pyEphem. I've tried a couple of different ways, and I get sort of the right answer, within a couple of degrees, but I'm expecting better, and I can't…
morvan68
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phephem: iss predictions not matching nasa website

I have been reading previous posts here but I still have a question. I am just making a very simple script to tell me when satellites are passing over my city. I am using this blog post as a guide:…
Paul P
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Precession, Proper Motion, and Epochs for Ancient or Future Observers

I have a question regarding epochs. I want to show the night sky as a super-ancient observer would see it or someone in the far flung future. Should I set the year and epoch to be the same? The three scenarios outlined in Brandon Rhodes Halley Comet…
electricwizard
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How to determine if it is daytime (light outside?) in python using ephem library

The ephem python library can perfectly determine the next sunrise and sunset. What I want to know is if it is light outside or not at a certain moment in time. Is there a simple function call in ephem that returns this?
rene
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Python Ephem / Datetime calculation

the output should process the first date as "day" and second as "night". I've been playing with this for a few hours now and can't figure out what I'm doing wrong. Any ideas? Edit I assume that the problem is due to my date comparison implementation…
dassouki
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Is there any way to calculate the visual magnitude of a satellite (ISS)?

Just got the basics of PyEphem working on my Raspberry Pi. Working really well. The approach to getting the next_pass of an object (in my case the ISS) is very useful... but I really also want to be able to take in to account the actual visual…
Liam Kennedy
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Wrong Range Rate with Pyephem

I am trying to calculate a satellites Range Rate using Python and pyephem. Unfortunately pyephems result seems to be wrong. After comparing the value with calculations made by other satellite tracking programs like GPredict or Ham Radio Deluxe the…
Sebastian
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Angle between two pairs of azimuth and altitude?

I have a solar panel pointing (it's normal vector) in some direction. I want to calculate the angle between that and the current position of the sun. I am using pyephem and I have this information in two pairs of azimuth and altitude. panel_az =…
Mads Skjern
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Computing sub-solar point

I am just getting started with PyEphem. My immediate task is, given a date and time compute the sub-solar point on Earth with latitude-longitude values. I'll dig into PyEphem to work this out but if someone has already done this, I'd appreciate…
Michael Zeiler
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PyEphem - Error next_pass()

trying to calculate is the time that a satellite rises above the horizon of an observer (TO), the time the satellite reaches the maximum elevation above the horizon (TCA) and the time a satellite passes below the observer's horizon (LOS) in a…
Luiz Gustavo Moura
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Sun Rising/Setting Azimuths for Equinox/Solstice using Observer points in PyEphem

Essentially what I am trying to do is: Take an Observer point (using lat/lon) Calculate the dates for the next equinox and solstice given a starting date Find the Sunset Azimuth for each Find the Sunrise Azimuth for each *Please note, I am working…
Spatial Pariah
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Installing Ephem package in Python 3

I would like to install the ephem package in my Python 3.3.0 version under Windows XP. I tried first the pip install ephem route from the system command prompt. The process aborted with the error message of Unable to find vcvarsall.bat. I read prior…
user2284034
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ECEF from Azimuth, Elevation, Range and Observer Lat,Lon,Alt

I'm trying to write a basic python script that will track a given satellite, defined with tle's, from a given location. I'm not a asto/orbital person but am trying to become smarter on it. I am running into a problem when I try to convert the…
user2084330
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pyephem - observer lat/lon types

Why was the decision made for the observers lat/lon numeric values to be treated as radians but string values to be treated as decimal degrees? When dealing with lat / lon values in Python I usually deal with floats objects. If the stars are…
Joseph Armbruster
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PyEphem: can I calculate Sun's altitude from azimuth

I am using PyEphem to calculate the location of the Sun in the sky at various times. I have an Observer point (happens to be at Stonehenge) and can use PyEphem to calculate sunrise, sunset, and the altitude angle and azimuth (degrees from N) for the…
davehunt00
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