Gaia Data Release 2. Cross-match with external catalogues - Algorithms and results

Understand

Context.

• Although the Gaia catalogue on its own is a very powerful tool, it is the combination of this high-accuracy archive with other archives that will truly open up amazing possibilities for astronomical research.
• The advanced interoperation of archives is based on cross-matching, leaving the user with the feeling of working with one single data archive.
• The data retrieval should work not only across data archives but also across wavelength domains.