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Comment by privong | Hacker News Reader

What type of things are you interested in doing? There's a pretty wide range of things in astronomy that lend themselves to the use of python (simulation analysis, data calibration, data display, etc.). The astropy[0] effort is creating a general-purpose package to aid in many areas. There are codes to compute how radiation transfers through gas (e.g., powderday[1]), fitting codes to observations of interstellar gas tracers (e.g., pyradexnest[2]), and so on. Many are fairly specialized (the last two, for example) and perhaps not as useful to a casual/amateur astronomer, but things like astropy would be useful for calibrating images from CCD cameras, or computing when things are visible in the sky.

If you reply with more specifics of what you're after, I can try to provide more relevant examples.

[0] http://www.astropy.org/

[1] http://powderday.readthedocs.org/en/latest/

[2] https://github.com/jrka/pyradexnest

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Quick Reply: I'm currently studying orbital-mechanics. Starting with something like Celestial Objects then downsizing to small-bodies later on. This has me reading up on Newtonian physics. With a solid understanding there, I'll move onto General Relativity.

My current open question (that may have been answered by this thread) was where can I obtain star-charts? How do I interact with them. Etc.

The simplest way forward is to use something like stellarium[0] or xephem[1] to make charts and view/adjust them in real-time. But that involves no python. :)

A more complicated option would be to program one up using various tools in the astropy library. You could retrieve catalogs of objects and plot their positions using the built in coordinate system tools (wcs) with aplpy[2] or matplotlib.

[0] http://www.stellarium.org/

[1] http://www.clearskyinstitute.com/xephem/

[2] https://aplpy.github.io/

I'm not to worried about the toolsets. I just want an amazing community. Thanks! On my next break, I'll dig into all of this!

Tip: you will also want to study structure-preserving numerical integration methods if you want to simulate planetary orbits. The book by Hairer, Wanner and Lubich is good (but not for the faint-of-heart).

Thanks! I'll look into it.

I haven't used it, but maybe poliastro is what you're looking for? https://poliastro.github.io

Disclaimer: I'm a friend of the author

I follow privong's suggestion for stellarium for celestial body visualization.

However, if you want precision data as an input to your code, I would make use of NASA JPL's ephemerides system [0]. It is precise and reliable. Another, more pythonic option is pyephem [1], which allows you to "calculate positions of stars and planets" at any given time.

Both options can be easily incorporated with astropy and APLpy, suggested by privong, for calculations and plotting.

[0] http://ssd.jpl.nasa.gov/?ephemerides

[1] https://pypi.python.org/pypi/pyephem/

Thanks, I'll look into this too!

Hey there! I'm a grad student in my last year and my research is in orbital dynamics. I've recently started getting into the rebound package written by Hanno Rein:

https://github.com/hannorein/rebound

There's some tutorials that come with it. It can also read data from JPL's ephemerides to calculate orbits of various planets and minor bodies in the Solar System. It has a couple of different integrators (some symplectic, some not), but one of them (IAS15) is new and (as far as I know) the best for long-term integrations of Solar-System-like systems.

Also if you're interested in studying the long-term evolution of hierarchical triples, I wrote a Python package to study that:

https://github.com/joe-antognini/kozai

As far as star charts, you can do things like that with AstroPy. If you want the coordinates of stars, look into astropy.vo, and then if you want to plot them, you can do that with some of the functions in astropy.wcs.

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