Oberon (moon) up to 40 km and its temperature is around 180 K. However, the internal structure of Oberon depends heavily on its thermal history, which is poorly known at present. Oberon is the second-darkest large moon of Uranus after Umbriel. Its surface shows a strong opposition surge: its reflectivity decreases from 31% at a phase angle of 0° (geometrical albedo) to 22% at an angle of about 1°. Oberon has a low Bond albedo of about 14%. Its surface is generally red in color, except for fresh impact deposits, which are neutral or slightly blue. Oberon is, in fact, the reddest
Oberon (operating system) Oberon operating system was originally developed as part of the NS32032-based Ceres workstation project. It was written almost entirely (and since the 2013 edition, now is described entirely) in the Oberon programming language. The basic system was designed and implemented by Niklaus Wirth and Jürg Gutknecht and its design and implementation is fully documented in their book "Project Oberon". The user Interface and programmers reference is found in Martin Reiser's book "The Oberon System". It was later extended and ported to other hardware by a team at ETH-Zürich and there was recognition in popular magazines. Wirth and Gutknecht (although being