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#esa

13 posts8 participants0 posts today

I tell people that Mr. Mittens is my Emotional Support Animal.

In truth I’m his Emotional Support Animal. But Mr. Mittens insists we continue to tell the lie because he’s vain and narcissistic about his image.

Replied in thread

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

lroc.im-ldi.com/images/298

Replied in thread

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

Continued thread

2025 June 28

Lunar Farside
* Image Credit: NASA / GSFC / Arizona State Univ. / Lunar Reconnaissance Orbiter
nasa.gov/
gsfc.nasa.gov/
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.

apod.nasa.gov/apod/ap250628.ht

TOPIC> The Moon

2025 July 20

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

Explanation:
About 1,300 images from the Lunar Reconnaissance Orbiter spacecraft's wide angle camera were used to compose this spectacular view of a familiar face - the lunar nearside. But why is there a lunar nearside? The Moon rotates on its axis and orbits the Earth at the same rate, about once every 28 days. Tidally locked in this configuration, the synchronous rotation always keeps one side, the nearside, facing Earth. As a result, featured in remarkable detail in the full resolution mosaic, the smooth, dark, lunar maria (actually lava-flooded impact basins), and rugged highlands, are well-known to earthbound skygazers. To find your favorite mare or large crater, just follow this link or slide your cursor over the picture. The LRO images used to construct the mosaic were recorded over a two week period in December 2010.
lroc.im-ldi.com/visit/exhibits

apod.nasa.gov/apod/ap250720.ht

Continued thread

The increasing demand for on-orbit servicing (#OOS) ♻️ tasks, such as #satellite repair, #SpaceDebris removal, refueling, and upgrades, has driven the need for advanced #robotic 🤖 systems capable of autonomous and precise operations in #space 🌌. #Germany’s 🇩🇪 #DEOS focuses on rendezvous, capture, and de-orbiting of an uncontrollable satellite from its operational orbit. #ESA's 🇪🇺 #SpaceServicing vehicle is anticipated to launch by 📆 2028 spj.science.org/doi/10.34133/s

Continued thread

#ESA Science Newsletter!

* Call for Expressions of Interest to become Member of the AWG/SSEWG & SSAC
* #SolarOrbiter gets world-first views of the Sun’s poles
* Date and content of next #Gaia Data Release
* Vacancy: #Cheops Project Scientist – advance notice
* Vacancy: Payload Validation Engineer
* Winter school: The exploration of Jupiter & its moons by ESA’s #Juice mission
* Results of the 9th call for the Archival Research Visitor Programme

▶️ cosmos.esa.int/web/scinews/202

SCI NewsIssue#05/2025 - 10 Jul 2025 - SCI News - Cosmos

1/2 The #geomagnetic reversal of the #earth combined with sound. Watching this video from #ESA @GFZ with my #synesthesia makes me nervous: youtube.com/watch?v=_blivWRpp80

It seems to be more a composition than exact sound mathematics? I see-hear the differences between picture and sound. And I can't hear any cacophony.

I imagine music in real translation of the paleomagnetic data, a transformation of data into sound ... that would be an experience!

Replied in thread

10 Years ago ..

2016 February 9

The Rise and Fall of Supernova 2015F
* Video Credit & Copyright: Changsu Choi & Myungshin Im (Seoul National University)
physics.snu.ac.kr/en

Explanation:
Sit back and watch a star explode. The actual supernova occurred back when dinosaurs roamed the Earth, but images of the spectacular event began arriving last year. Supernova 2015F was discovered in nearby spiral galaxy NGC 2442 by Berto Monard in 2015 March and was unusually bright -- enough to be seen with only a small telescope. The pattern of brightness variation indicated a Type Ia supernova -- a type of stellar explosion that results when an Earth-size white dwarf gains so much mass that its core crosses the threshold of nuclear fusion, possibly caused by a lower mass white-dwarf companion spiraling into it. Finding and tracking Type Ia supernovae are particularly important because their intrinsic brightness can be calibrated, making their apparent brightness a good measure of their distance -- and hence useful toward calibrating the distance scale of the entire universe. The featured video tracked the stellar disruption from before explosion images arrived, as it brightened, and for several months as the fission-powered supernova glow faded. The remnants of SN2015F are now too dim to see without a large telescope. Just yesterday, however, the night sky lit up once again, this time with an even brighter supernova in an even closer galaxy: Centaurus A.

apod.nasa.gov/apod/random_apod

Replied in thread

Arp 87: Merging Galaxies from Hubble
* Image Credit: NASA, ESA, Hubble
nasa.gov/
esa.int/
science.nasa.gov/mission/hubbl
* Processing: Harshwardhan Pathak
skiesandscopes.com/harshwardha

Explanation:
This dance is to the death. As these two large galaxies duel, a cosmic bridge of stars, gas, and dust currently stretches over 75,000 light-years and joins them. The bridge itself is strong evidence that these two immense star systems have passed close to each other and experienced violent tides induced by mutual gravity. As further evidence, the face-on spiral galaxy on the right, also known as NGC 3808A, exhibits many young blue star clusters produced in a burst of star formation. The twisted edge-on spiral on the left (NGC 3808B) seems to be wrapped in the material bridging the galaxies and surrounded by a curious polar ring. Together, the system is known as Arp 87. While such interactions are drawn out over billions of years, repeated close passages will ultimately create one merged galaxy.
Although this scenario does look unusual, galactic mergers are thought to be common, with Arp 87 representing a stage in this inevitable process. The Arp 87 dancing pair are about 300 million light-years distant toward the constellation of the Lion (Leo). The prominent edge-on spiral galaxy at the far left appears to be a more distant background galaxy and not involved in the on-going merger.
en.wikipedia.org/wiki/Arp_87
science.nasa.gov/missions/hubb

cv.nrao.edu/~jhibbard/MergeSeq
cv.nrao.edu/~jhibbard/MergeSeq

apod.nasa.gov/apod/ap140715.ht
apod.nasa.gov/apod/ap061111.ht
ui.adsabs.harvard.edu/abs/1972

en.wikipedia.org/wiki/Leo_(con

apod.nasa.gov/apod/ap231024.ht