Theon Junior

From The Moon
Jump to: navigation, search

Theon Junior

Lat: 2.3°S, Long: 15.8°E, Diam: 17 km, Depth: 3.58 km, Rükl: 45

external image normal_Theon-Junior_LO-IV-090H_LTVT.JPG


LPOD Photo Gallery Lunar Orbiter Images Apollo Images
Theon Junior "behind" nearby Delambre, as seen by Apollo 10: AS10-32-4733 (looking west-southwest).
Theon Junior was also photographed during the mission of Apollo 16 in april 1972. It was captured near the rightmost margins of ITEK-camera frames AS16-P-5324, AS16-P-5326, and AS16-P-5331.
Additional research orbital Apollo 10 and Apollo 16 photography: Danny Caes


(LAC zone 78A2) LAC map Geologic map LM map AIC map


Description: Elger

(IAU Directions) THEON JUNIOR.--A ring-plain similar in size and in other respects to Theon Senior, situated about 23 miles S. of it on a somewhat dusky surface. Between the pair is a curious oblong-shaped mountain mass; and on the W. a long cliff (of no great altitude, but falling steeply on the W. side) extending S. towards Taylor a. Just below the escarpment, I find a brilliant little pair of craterlets, of which Neison only shows one.

Description: Wikipedia

Theon Junior

Additional Information

Depth data from Kurt Fisher database
  • Arthur, 1974: 3.58 km
  • Westfall, 2000: 3.58 km
  • Viscardy, 1985: 3.58 km
  • Cherrington, 1969: 2.71 km
  • From the shadows in LO-IV-090H, the depth of Theon Junior is greatest towards the north: about 3600 m, decreasing to under 3400 m as one moves south. - Jim Mosher
  • Included on the ALPO list of banded craters
  • Theon Junior B, a small crater west of Theon Junior itself, shows a curious "extra internal rim" at its northwestern part (source: the online ACT-REACT Quick Map of the Lunar Reconnaissance Orbiter's photography). - DannyCaes Aug 9, 2014


Theon of Alexandria (ca. 335 - ca. 405 AD) was a Greek scholar in Alexandria, Egypt, and the last director of the Library of Alexandria before it was burnt and destroyed by Christian riots. Theon's most durable achievement may be his edition of Euclid's Elements, published around 364 and authoritative into the 19th century. The bulk of Theon's work, however, consisted of commentaries on important works by his Hellenistic predecessors.

    • Note that "Theon Senior" and "Theon Junior" were not father and son, as they lived in different centuries.
    • According to Whitaker (p. 215), Riccioli used the name "Theon sen." to label the modern crater Taylor A. He does not seem to explain how the name got moved to its present position. - Jim Mosher

  • ==LPOD Articles==

How Deep is that Hole?

  • ==Bibliography==

  • ----