问题
I am trying to build an astronomy application where I should display the stars at and near zenith for a given latitude, longitude and time.
I am aware of the basics of Positional astronomy, what is puzzling me is to create database out of huge set of data!
My Queries are:
- Which catalogue to prerfer? Like Hipparcos catalogue or Henry Draper? What are its advantages and disadvantages?
- What fields are required? I have identified some, but what else should be added and why? Fields identified by me: Star name, Some Unique star ID, RA, Dec, Magnitude,Color of the star.
- I tried to figure out from which table to fetch the Common Star name from the Hipparcos catalogue without any luck: http://vizier.u-strasbg.fr/cgi-bin/VizieR-2?-source=I/239. I couldnt find in any of the tables.
Thanks, Raj
回答1:
I prefer BSC and Hipparcos catalogs
BSC is for naked eye apps (Bright Star Catalog up to
6.5 mag
). It is free and not too big to handle (9110
stars)...Hipparcos is for astro apps (up to
12.5 mag
) and is also with manageable size (118322
stars). It also contains paralaxes which means you can obtain 3D position data which is cool for stereo 3D imaging. The original file size in ASCII format is12.3 MB
. I compile it to these binary forms:(rec,dec,distance,RGB) 32bit -> 2.364MB (x,y,z,RGB) 32bit -> 2.364MB
Which is small/fast enough for storing in memory and direct rendering.
what fields to use
Absolute minimum to decode/use are: RA,DE,Vmag,B-V. For more precision add also motions pmRA,pmDE. If you want 3D add paralax Plx but also check if its error is not too high e_Plx. Also sometimes you need the ID of star in catalog HIP for example for star constellations mesh
star names tables
They usually refers to BSC by ID of star but here for example are more catalogs cross-reference with Hipparcos included.
来源:https://stackoverflow.com/questions/5676853/astronomy-application