Cross-matching 2 catalogs

Astropy
1

Dear all

I want to cross-match two catalogs. But the Dec and RA coordinate data of these two catalogs are written as “h m s” and “d m s” (instead of being separated by a “:” a space separates them).

RAJ2000

00 32 41.56
00 32 41.55
…

That’s why I think my code gives an error.
*"TypeError: unsupported operand type(s) for : ‘MaskedColumn’ and ‘Unit’"

Is there a command where I can either add all the coordinates in degrees to my tables, or add colons between the given coordinates?

‌Best regards.

Hamid

2

Hi,

You should be able to do this to construct a SkyCoord instance:

RA = ['00 32 41.56', '00 32 41.55']
Dec = ['12 34 56.78', '23 45 27.78']
c = coord.SkyCoord(RA, Dec, unit=(u.hourangle, u.degree))

(replace RA, Dec with your column data)

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