The SDSS is not the first sky survey, nor will it be the last. The SDSS will be the most comprehensive catalog of objects ever made for the northern sky, and astronomers will use its data for many years to come.

SDSS’s data become even more valuable when you can compare them with data from other sky surveys such as POSS to see if any changes have occurred over time, and with data from sky surveys in other wavelengths.

Research Challenge. Select an object that interests you from the SDSS database. It could be an object from the SkyServer DR16 Famous Places list, or an object you find with the Navigation Tool. Look up data on the object in POSS, 2MASS, ROSAT, and any other sky survey databases you can find.

What is the object? What does it look like in different surveys? Why do you think it looks the way it does? What other data (spectra, for example), can you find for the object?

Learn as much as you can about your object!