"Lunar Nearside" is #NASA #astronomy picture of the day for 2025-07-20 - a composite of 1300+ images from NASA GSFC, Arizona State University and the Lunar Reconnaissance Orbiter (LRO) shows the entire near side of the #Moon in stunning and clear detail. https://apod.nasa.gov/apod/ap250720.html

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Timeline for next 5 billion years

(make sure to make notes in your diaries)

via pangeen

Orbit the Moon! - LROC WAC Global Mosaic and DTM

The Lunar Reconnaissance Orbiter Camera (LROC) WAC is a push-frame camera that captures seven color bands (321, 360, 415, 566, 604, 643, and 689 nm) with a 57-km swath (105-km swath in monochrome mode) from a 50 km orbit. One of the primary objectives of LROC is to provide a global 100 m/pixel monochrome (643 nm) base map with incidence angles between 55°-70° at the equator, lighting that is favorable for morphological interpretations. Each month, the WAC provides nearly complete coverage of the Moon under unique lighting. As an added bonus, the orbit-to-orbit image overlap provides stereo coverage. Reducing all these stereo images into a global topographic map is a big job, and is being led by LROC Team Members from the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt; DLR). Several preliminary WAC topographic products have appeared in LROC featured images (Orientale basin, Sinus Iridum). For a sneak preview of the WAC global DEM with the WAC global mosaic, view a rotating composite Moon (Full Res).

The global mosaic comprised of over 15,000 WAC images acquired between November 2009 and February 2011. The non-polar images were map projected onto the GLD100 shape model (WAC derived 100 m/pixel DTM), while polar images were map projected on the LOLA shape model. In addition, the LOLA derived crossover corrected ephemeris, and improved camera pointing, provide accurate positioning (100 m) of each WAC image.

CREDIT
LROC
WAC
DLR

https://lroc.im-ldi.com/images/298

Tidal locking

results in the Moon rotating about its axis in about the same time it takes to orbit the Earth. Except for libration effects, this results in it keeping the same face turned towards the Earth, as seen in the figure on the upper left. (The Moon is shown in polar view, and is not drawn to scale.)

+ Upper left:
> If the Moon didn't spin at all, then it would alternately show its near and far sides to the Earth while moving around our planet in orbit.

+ Upper right:
> If rotational frequency is larger than orbital frequency, a small torque counteracting the rotation arises, eventually locking the frequencies (situation depicted in green)

+ Down left:
> A simulation shows the variability in the portion of the Moon visible from Earth due to libration over the course of an orbit. Lighting phases from the Sun are not included.

+ Down right:
> Animation of the Moon as it cycles through its phases. The apparent wobbling of the Moon is known as libration

From Wikipedia, the free encyclopedia

CREDITS
Contributors to Wikimedia projects
* Stigmatella aurantiaca
* Jim McKeeth
* Tom Ruen
* Poopooman-ger

2025 June 28

Lunar Farside
* Image Credit: NASA / GSFC / Arizona State Univ. / Lunar Reconnaissance Orbiter
https://www.nasa.gov/
https://www.gsfc.nasa.gov/
https://lroc.sese.asu.edu/index.html

Explanation:
Tidally locked in synchronous rotation, the Moon always presents its familiar nearside to denizens of planet Earth. From lunar orbit, the Moon's farside can become familiar, though. In fact this sharp picture, a mosaic from the Lunar Reconnaissance Orbiter's wide angle camera, is centered on the lunar farside. Part of a global mosaic of over 15,000 images acquired between November 2009 and February 2011, the highest resolution version shows features at a scale of 100 meters per pixel. Surprisingly, the rough and battered surface of the farside looks very different from the nearside covered with smooth dark lunar maria. A likely explanation is that the farside crust is thicker, making it harder for molten material from the interior to flow to the surface and form dark, smooth maria.

https://apod.nasa.gov/apod/ap250628.html