|ODIS=One Day Iterative Solution
order to reach the level of precision targetted by Gaia, many months of
observational data must be incorporated into a global, complex data reduction process in order to perform a self-calibration of the satellite and subsequently to determine the astrometric and global parameters. Subtle malfunctions in the spacecraft or payload may impact on the measurement precision and instrument stability and hence degrade the final results. The 'First-Look' activity is designed to allow early identification of these types of effects so that they can be corrected.
First Look will perform an in-depth scientific assessment of the
quality of the Gaia observations within 24 hours after they are received at the data processing centre. The One Day Iterative Solution (ODIS) is one of two methods presently under investigation
which may perform this kind of analysis. The ODIS
is an iterative (i.e. repetitive) scheme of complex computations. By calculating successively improved estimates of the relevant astronomical and instrumental parameters it ultimately tells us whether the individual measurements by Gaia "fit together".
More detailed information about ODIS will follow soon....
A realistic numerical experiment for ODIS:
A new experiment for ODIS with 40000 stars:
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