Demonstrating Redshift Drift from Archival Spectroscopic Data

This brief presents a proof-of-concept study demonstrating that redshift drift can be extracted from existing spectroscopic datasets, challenging the assumption that such measurements require future telescopes. Using repeated observations from Sloan Digital Sky Survey (SDSS) and MaNGA, redshifts were compared over an ~8-year baseline. The study finds a small but measurable shift in redshift, suggesting that archival data can provide insights into cosmic expansion today.

The methodology includes:

• Data retrieval and selection of repeat spectroscopic observations.
• AI-assisted spectral processing to extract redshifts.
• Mathematical validation using Hα emission lines.
• Discussion of observational uncertainties and possible systematics.

The study concludes that while the dataset is small, this approach encourages further research with expanded datasets. Future efforts should focus on systematic error control, dataset expansion, and cross-validation with high-precision instruments such as ESPRESSO and ELT-HIRES.