SDSS9 color survey collection

The Sloan Digital Sky Survey is a multi-filter imaging and spectroscopic redshift survey using a dedicated 2.5-m wide-angle optical telescope at Apache Point Observatory in New...斯隆数字巡天（Sloan Digital Sky Survey）是一项多滤镜成像与光谱红移巡天项目，其使用安置于新...阿帕奇点天文台的专用2.5米广角光学望远镜开展观测。