Exploring new methods
New spectral classification techniques galaxy spectra can be expressed as a superposition of a few (ɝ) principal components => objective classification of 1 million spectra!
Photometric redshifts galaxy colors systematically change with redshift, the SDSS photometry works like a 5-pixel spectrograph => ?z=0.05, but with 100 million objects!
Measuring cosmological parameters before: data analysis was limited by small number statistics after: dominant errors are systematic (extinction) => new analysis methods are required!