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Lat: 20.5°N, Long: 20.6°W, Diam: 20 km, Depth: 2.54 km, Rükl: 20, Copernican

external image normal_Pytheas_LO-IV-126H_LTVT.JPG
LO-IV-126H The 5-km diameter crater above Pytheas is Pytheas D.


LPOD Photo Gallery Lunar Orbiter Images Apollo Images
- Pytheas Beta, the hillock at 20° North/ 24° West which was once called Mount Dyson by Percy Wilkins and Patrick Moore, was captured on several frames of Apollo 17's orbital panoramic ITEK-camera. One of them, frame AS17-P-3090, shows Mount Dyson (Pytheas Beta) pretty well.
- Is Pytheas G a craterlet with central peak? See AS17-P-3074.
Additional research orbital Apollo 17 photography: Danny Caes


(LAC zone 40D2) LAC map Geologic map LTO map


Description: Elger

(IAU Directions) PYTHEAS.--A small rhomboidal-shaped ring-plain, 12 miles in diameter, standing in an isolated position on the Mare Imbrium between Lambert and Gay-Lussac. Its bright walls, rising about 2,500 feet above the Mare, are much terraced within, especially on the W. There is a bright little crater on the N. outer slope, with a short serpentine ridge running up to it from the region S. of Lambert, and another winding ridge extending from the S. wall to the W. of two conspicuous craters, standing about midway between Pytheas and Gay-Lussac. The former bears a great resemblance to the ridge N. of Madler, and, like this, appears to traverse the N. border. The interior of Pytheas, which is depressed more than 2,000 feet below the Mare, includes a brilliant central peak.

Description: Wikipedia


Additional Information

  • Depth data from Kurt Fisher database
    • Pike, 1976: 2.54 km
    • Arthur, 1974: 2.54 km
    • Westfall, 2000: 2.54 km
    • Viscardy, 1985: 2.53 km
    • Cherrington, 1969: 2.16 km
  • The longest shadow in LO-IV-126H indicates a height difference of slightly over 2600 m. - Jim Mosher
  • Mapped as Copernican because has rays but some parts of rays are mature and others are not – strange result being investigated. (Hawke et al: Composition and origin of Copernican Rays… Mappers Conference 2005)
  • Thermal anomaly crater, implying youthful age - Moore et al, 1980
  • A weird shaped depression near Pytheas G (slightly southeast of Pytheas G) is mentioned in APOLLO OVER THE MOON: A VIEW FROM ORBIT, Chapter 7: Unusual Features (Part 2), Figure 243. Detection of this weird depression's exact location: Danny Caes.
  • Included in ALPO list of bright ray craters
  • Included on the ALPO list of banded craters
  • Oblique impact crater with widening of cross-range direction suggest impact angle of 15° (Forsberg, Herrick & Bussey, 2008).
  • TSI = 25, CPI = 5, FI = 15; MI =55 Smith and Sanchez, 1973


  • Named for Pytheas (ca. 380 – ca. 310 BC), a Greek merchant, geographer and explorer from the Greek colony Massilia (today Marseille, France). He made a voyage of exploration to northwestern Europe around 325 BC. He probably travelled around a considerable part of Great Britain, circumnavigating it between 330 and 320 BC. Pytheas is the first person on record to describe the Midnight Sun, the aurora and polar ice, and the first to mention the name Britannia and Germanic tribes.
  • Pytheas Beta, a small solitary hill west-southwest of Pytheas itself, was called Mount Dyson by Wilkins and Moore, but the I.A.U. did not accept that name. The name Dyson was eventually used for a farside crater.
  • Tiny white island. A nickname from Danny Caes for the officially unnamed hillock (or "island") east-southeast of Pytheas K. This tiny hillock shows a high-albedo spot at its northern slope. Its pinpoint location is LAT: 19.00 / LON: -14.45 (see the LROC ACT-REACT QUICK MAP for several NAC close ups of it).

LPOD Articles

Rays & Pitts Mare Layering


  • Dark streaks on Pytheas's southern inner slopes:
    • APOLLO OVER THE MOON; A VIEW FROM ORBIT, Chapter 5: Craters (Part 3); Figure 125, (Part 4); Figure 146.