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The LSST will be situated in Chile at a latitude of -30 degrees. From there it can usefully access the sky up to a declination of +30 degrees. The full sky is 41,253 square degrees, and LSST plans to conduct a survey over 20,000 square degrees in addition to a few "deeper" fields that will receive longer and more frequent observations.
This implies that we need to schedule observations in 6 bands, spread across 20,000/9.6~2100 fields over the course of 10 years.
Images are obtained in 6 different optical passbands, designated u,g,r,i,z and y, that span the atmospheric cutoff at 340 nm up to the longest wavelength that can be detected in silicon CCDs, about one micron.
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