Star catalogue analysis

Thanks to UCF Physics undergrad Tyler Townsend for contributing to the development of this notebook.



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# Import modules that contain functions we need
import pandas as pd
import numpy as np
%matplotlib inline
import matplotlib.pyplot as plt

Getting the data



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# Read in data that will be used for the calculations.
# Using pandas read_csv method, we can create a data frame
data = pd.read_csv("https://raw.githubusercontent.com/merryjman/astronomy/master/stars.csv")
datatwo = pd.read_csv("https://raw.githubusercontent.com/astronexus/HYG-Database/master/hygdata_v3.csv")



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# We wish to look at the first 12 rows of our data set

data.head(12)

Star map



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fig = plt.figure(figsize=(15, 4))
plt.scatter(data.ra,data.dec, s=0.01)
plt.xlim(24, 0)
plt.title("All the Stars in the Catalogue")
plt.xlabel('right ascension (hours)')
plt.ylabel('declination (degrees)')

Let's Graph a Constellation!



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# These are the abbreviations for all the constellations
datatwo.sort_values('con').con.unique()



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# This shows just one constellation.
datatwo_con = datatwo.query('con == "UMa"')

#Define a variable called "name" so I don't have to keep renaming the plot title!
name = "Ursa Major"

# This plots where the brightest 15 stars are in the sky
datatwo_con = datatwo_con.sort_values('mag').head(15)
plt.scatter(datatwo_con.ra,datatwo_con.dec)
plt.gca().invert_xaxis()

# I graphed first without the line below, to see what it looks like, then
# I added the plt.xlim(25,20) to make it look nicer.

plt.xlim(15,8)
plt.ylim(30,70)
plt.title('%s In the Sky'%(name))
plt.xlabel('right ascension (hours)')
plt.ylabel('declination (degrees)')

Let's Go Back in Time!



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# What did this constellation look like 50,000 years ago??
plt.scatter(datatwo_con.ra-datatwo_con.pmra/1000/3600/15*50000,datatwo_con.dec-datatwo_con.pmdec/1000/3600*50000)
plt.xlim(15,8)
plt.ylim(30,70)

plt.title('%s Fifty Thousand Years Ago!'%(name))
plt.xlabel('right ascension (hours)')
plt.ylabel('declination (degrees)')

Let's Go Into the Future!



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# Now, let's try looking at what this same constellation will look like in 50,000 years!
plt.scatter(datatwo_con.ra+datatwo_con.pmra/1000/3600/15*50000,datatwo_con.dec+datatwo_con.pmdec/1000/3600*50000)

plt.xlim(15,8)
plt.ylim(30,70)
plt.title('%s Fifty Thousand Years From Now!'%(name))
plt.xlabel('right ascension (hours)')
plt.ylabel('declination (degrees)')

Now you try one of your own!



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# Make a Hertzsprung-Russell Diagram!

References

The data came from The Astronomy Nexus and their colletion of the Hipparcos, Yale Bright Star, and Gliese catalogues (huge zip file here).
Reversed H-R diagram from The Electric Universe
Many thanks to Adam Lamee and his colleagues at codingink12.org for basically making this whole thing.