An example how to read data from the ANTARES webpage and figuring out the coordinate system. Superseded by other examples in this directory!
import pandas as pd
from astropy.coordinates import SkyCoord
from astropy.coordinates import FK5
url="https://antares.in2p3.fr/PublicData_0717.dat"
cols = ["Decl","RA","Nhit","Beta","MJD"]
c = pd.read_csv(url, sep='\t', skiprows=(0,1), names=cols)
from https://docs.astropy.org/en/stable/coordinates/ ICRS: international celestial reference system
def coordformat(alpha,delta):
coordinate = SkyCoord(ra=alpha,dec=delta, frame = 'fk5', unit = 'deg')
coordinate_fk5 = coordinate.transform_to(FK5(equinox = 'J2000'))
coordinate_fk5_formatted = coordinate_fk5.to_string('hmsdms')
a = coordinate_fk5.ra
d = coordinate_fk5.dec
return coordinate_fk5
# apply coordformat function to the first two columns of dataframe
df2=c.apply(lambda r: coordformat(r[1], r[0]), axis = 1)
print(df2)
0 <SkyCoord (FK5: equinox=J2000.000): (ra, dec) ...
1 <SkyCoord (FK5: equinox=J2000.000): (ra, dec) ...
2 <SkyCoord (FK5: equinox=J2000.000): (ra, dec) ...
3 <SkyCoord (FK5: equinox=J2000.000): (ra, dec) ...
4 <SkyCoord (FK5: equinox=J2000.000): (ra, dec) ...
...
8749 <SkyCoord (FK5: equinox=J2000.000): (ra, dec) ...
8750 <SkyCoord (FK5: equinox=J2000.000): (ra, dec) ...
8751 <SkyCoord (FK5: equinox=J2000.000): (ra, dec) ...
8752 <SkyCoord (FK5: equinox=J2000.000): (ra, dec) ...
8753 <SkyCoord (FK5: equinox=J2000.000): (ra, dec) ...
Length: 8754, dtype: object
res_dict = dict(ra=df2.apply(lambda x: x.ra), dec=df2.apply(lambda x: x.dec))
res_df = pd.DataFrame(res_dict)
print(res_df)
ra dec 0 68d12m00s 19d30m00s 1 26d30m00s -60d00m00s 2 82d06m00s -29d48m00s 3 271d48m00s -8d36m00s 4 261d24m00s -32d18m00s ... ... ... 8749 224d42m00s -12d24m00s 8750 45d54m00s -34d06m00s 8751 123d42m00s -57d36m00s 8752 108d42m00s -33d30m00s 8753 144d00m00s -46d42m00s [8754 rows x 2 columns]