Key to the designations is given in the table below:
Prefix Survey Name COD Era ------ ----------------- --- ----------------------- FS-nnn = First SPACEWATCH® 691 circa 1984-1988) SS-nnn = Second SPACEWATCH® 691 circa 1989-2002 Apr 23) ts-nnn = Third SPACEWATCH® 291 circa 2001-2011 Oct 1) SW4xxx = 4th SPACEWATCH® 691 2002 Apr 24 -present) SW5xxx = 5th SPACEWATCH® 291 2011 Oct 16 - present) SW6xxx = 6th SPACEWATCH® ^695 2010 - 2017) using KPNO Mayall 4-meter telescope. SWBxxx = Bok SPACEWATCH® ^695 2016 Apr 18 - present using Steward Bok 2.3-m telescope. where "nnn" = an integer from 001 to 999 and "xxx" = a heirarchical string of characters running sequentially through digits 0-9, letters a-z (lower-case), followed by A-Z (upper-case). From 1984 April through 2002 April 23, COD 691 was the Steward Observatory 0.9-meter f/5 Newtonian telescope with various CCDs of increasing size with time (also see: 0.9-meter telescope equipment epoch table). COD 691 is presently a 0.9-meter f/3 telescope with corrected prime focus and four CCDs in a mosaic covering an area of 2.9 square degrees (also see: 0.9-meter telescope equipment epoch table). COD 291 is the SPACEWATCH® 1.8-meter telescope with a 2048x2048 CCD at folded, corrected f/2.7 prime focus (also see: 1.8-meter telescope equipment epoch table).