Modify FITS table

for_hilbert.py

"""
Ref: https://gist.github.com/bhilbert4/1d61054a4aeb2692831c629c28f811c8
"""
from astropy.io import fits

pf = fits.open('jwst_nircam_photom_0031.fits')
col_list = []

# Copy existing columns to new table. Here, I am only showing two as example.
for colname in ('filter', 'pupil'):
    col_list.append(fits.Column(name=colname, format=pf[1].columns[colname].format, array=pf[1].data[colname]))
    
# Create new column. For example, your bigger wavelength column.
col_list.append(fits.Column(name='wavelength', format='3000E', array=np.zeros((15, 3000))))

# Create new binary table from your columns.
tbhdu = fits.BinTableHDU.from_columns(col_list)

# Create new HDU list with existing primary header and new table.
hdulist = fits.HDUList()
hdulist.append(pf[0])
hdulist.append(tbhdu)

# Write to new table.
hdulist.writeto('newtab.fits')

# Clean up.
pf.close()

# Outside Python session, you can simply use "mv" to replace old table with new table.