Ramsden Rilles (with the "N" just north of Ramsden)
(informal name; IAU name: Rimae Ramsden)
Lat: 33.9°S, Long: 31.4°W, Length: 108 km, Depth: km, Rükl: 63
- Discovered by Schmidt, Jan 4, 1849 at Bonn – (Astronomical Register) 1865 vol 3, p 190-1.
- The system of three rilles just north of Ramsden (which are almost typographically "N"-shaped), is an interesting target for telescope operators at public observatories! - DannyCaes Aug 4, 2009
- Named after the nearby crater (Ramsden).
- The original IAU nomenclature of Blagg and Müller included three Ramsden rilles: Ir= Cat. no. 2571, IIr= Cat. no. 2572, and IIIr ("a system of two parallel rilles") = Cat. no. 2572a.
- The August 4, 2009 LPOD shows the numbering system as revised in the System of Lunar Craters. Blagg and Müller's Ir was extended to the north through Ramsden, possibly incorporating part of Blagg and Müller's IIIr. Blagg and Müller's IIr was extended in the northeast and shortened in the southwest. IIIr was confined to a single branch, the western component being renamed Rima Ramsden V and extended to the south through Ramsden. Finally, the numbers IV and VI were added for rilles unnamed in Blagg and Müller.
- None of the Roman-numeraled rille designations are included in the current IAU Planetary Gazetteer, where the entire complex is simply called Rimae Ramsden. The precise branches the name applies to is unclear.
- The LPOD describes an additional rille to the north, provisionally called Rima Ramsden VII. This rille was Mercator Ir in Blagg and Müller (Cat. no. 2570). This rille was renamed Rima Campanus I on LAC-94, but left unlabeled in the System of Lunar Craters (sheets E6 and E7). The Wikipedia authors also describe this rille as part of the Rimae Ramsden system, although it falls far outside the circle attributed to that name based on the position and diameter in the IAU Planetary Gazetteer (and listed in the title line, above).
Harold Hill. A Portfolio of Lunar Drawings, pages 154, 155 (the western portion of Palus Epidemiarum).