Le Mystère des Volcans Lunaires Pourrait Enfin Être Résolu

Sympa

La Lune peut sembler calme et silencieuse maintenant, mais il y a longtemps, c'était une boule de feu d'activité volcanique ! 🌋 Des scientifiques ont été perplexes pendant des années à propos de mystérieuses zones chaudes sous sa surface, mais maintenant, ils pensent avoir résolu le mystère. Il s'avère que d'énormes chambres de lave souterraines provenant d'éruptions anciennes refroidissent encore lentement, gardant certaines zones plus chaudes que prévu. Ces "poches chaudes" cachées (pas celles du type snack ! 😆) contribuent à expliquer pourquoi la Lune n'est pas complètement congelée à l'intérieur. Cette découverte pourrait même changer ce que nous savons sur la façon dont les lunes et les planètes se refroidissent avec le temps. Qui savait que la Lune conservait encore ses secrets volcaniques ? 🌕🔥  Animation créée par Sympa. ---------------------------------------------------------------------------------------- Musique par Epidemic Sound https://www.epidemicsound.com   Pour ne rien perdre de Sympa, abonnez-vous!: https://goo.gl/6E4Xna​ ---------------------------------------------------------------------------------------- Nos réseaux sociaux : Facebook: https://www.facebook.com/sympasympacom/ Instagram: https://www.instagram.com/sympa.officiel/  Stock de fichiers (photos, vidéos et autres): https://www.depositphotos.com https://www.shutterstock.com https://www.eastnews.ru ----------------------------------------------------------------------------------------  Si tu en veux encore plus, fais un tour ici:  http://sympa-sympa.com

Transcript

00:00Lunar volcanoes are not asleep, and could erupt at any time.

00:05For years, this possibility has remained unknown.

00:09But the Chinese mission Chang'e-5 has brought a stunning revelation.

00:15The samples of lunar soil brought back to Earth contain a totally unexpected element,

00:20suggesting that volcanic eruptions would have occurred on the Moon only 123 million years ago.

00:26From a geological point of view, this is equivalent to yesterday.

00:30But a major question arises.

00:32Does this activity represent a danger for us on Earth?

00:36We have known for a long time that the Moon has been the scene of an intense volcanic activity,

00:41as evidenced by the vast dark regions of its surface, called lunar seas.

00:47These dark plains, which mark the face of the Moon, are actually ancient lava flows dating from 3 to 3.8 billion years.

00:56Until recently, scientists thought that these traces marked the definitive end of lunar volcanism.

01:02However, the samples brought back by Chang'e-5 contained tiny glass pearls,

01:07three of which in particular revealed an extraordinary fact.

01:11They formed as a result of volcanic eruptions about 123 million years ago.

01:17The margin of uncertainty is remarkably small, at only 15 million years.

01:21This discovery is of great importance because of the composition and rarity of these pearls.

01:27Measuring between 20 and 400 microns, or less than a grain of sand, they are of volcanic origin.

01:34This detail distinguishes them from most other lunar glass pearls, which generally result from meteorological impacts.

01:43Meteorological impacts produce glass by melting the lunar rock under the effect of extreme heat and pressure,

01:50thus forming tiny glass balls scattered on the surface.

01:55On the other hand, the volcanic pearls discovered in the sample of Chang'e-5

02:00come from the eruption of magma from the depths of the lunar crust, which solidified into glass when it reached the surface.

02:08Thanks to the uranium-lead dating, which allows to measure the disintegration of uranium-lead in pearls,

02:14scientists were able to establish their age with remarkable precision.

02:19The results indicate that the last known volcanic event on the Moon occurred in the last 200 million years,

02:26which, on the scale of its history, makes it a relatively recent event.

02:31This discovery also corroborates previous observations on atypical surface formations, called Irregular Mare Patches.

02:39These structures, made up of smooth mounds surrounded by rocky terrain,

02:44were first identified in 2014 by NASA's Lunar Reconnaissance Orbiter.

02:49They appear much younger than other lunar reliefs and could result from volcanic eruptions that occurred less than 100 million years ago.

02:59Before the analysis of the glass pearls reported by Chang'e-5,

03:02these formations constituted one of the most probable indications of a recent volcanic event on the Moon.

03:07However, due to lack of confirmation, their origin remained uncertain.

03:12Now, these balls come to indisputably confirm the existence of a past volcanic activity.

03:18These discoveries raise new questions about the internal mechanisms of the Moon.

03:23How was it able to retain enough heat to feed volcanic eruptions?

03:27Until now, scientists thought that the Moon had cooled significantly after its formation 4.5 billion years ago, making all volcanism impossible.

03:38In the absence of tectonic activity and atmosphere, the Moon should have lost its internal heat for a long time.

03:44However, these glass pearls suggest the existence of heat sources located within its mantle.

03:51Researchers estimate that some radioactive elements, such as potassium and thorium,

03:56could generate thermal pockets capable of maintaining a sufficient temperature to melt the rock and cause punctual volcanic eruptions.

04:04That's not all.

04:05Beyond the rewriting of lunar history, this discovery brings a new enlightenment on transitory lunar phenomena.

04:14These manifestations, described by amateur astronomers in the form of evanescent glow or fluid mist,

04:20have never been confirmed by scientific instruments.

04:24Some specialists simply consider them as illusions due to the Earth's atmosphere.

04:29However, if the Moon is home to small zones of volcanic activity or degassing,

04:35transitory lunar phenomena could be real.

04:39Underground gas emissions could explain these mysterious glows and indicate residual volcanic activity on the Moon.

04:46If volcanic activity persists on the Moon, the repercussions for future missions could be considerable.

04:54In the decades to come, astronauts could exploit this heat to produce energy,

05:00transform ice into water, or even temper the bases installed on the lunar surface, where temperatures are extreme.

05:08But recent advances in planetary geology are not limited to the Moon.

05:12Observations suggest that volcanic activity could be common among extrasolar moons.

05:18The detection of a potential volcanic exolunum orbiting the exoplanet WASP-49b,

05:24located about 635 light-years away, could question our conception of volcanic bodies.

05:32So far, Io, Jupiter's moon, has held the record for volcanic activity,

05:38but NASA's Jet Propulsion Laboratory researchers believe they have identified a new candidate.

05:45Scientists have detected this potential exolunum by detecting a cloud of sodium orbiting the exoplanet.

05:53However, the presence of such a cloud is unusual in planetary atmospheres and could be a sign of volcanic activity.

06:00The one observed near WASP-49b is distinguished by its erratic behavior.

06:06It changes size, moves unpredictably, and occupies a volume far too large to be explained only by the exoplanet's atmosphere.

06:15This suggests that this gaseous mass would come from a volcanic exolunum in orbit.

06:22Volcanic moons like Io release large amounts of sulfur dioxide,

06:27sodium and potassium, creating huge clouds around their high planets.

06:34Io, for example, regularly emits enough gas to create an envelope

06:39that extends up to a thousand times the size of Jupiter around the planet.

06:44If a similar phenomenon occurs near WASP-49b,

06:49this would reinforce the hypothesis of an active exolunum.

06:53The observation carried out by the European-Australian Observatory in Chile seems to support this theory.

07:01The cloud of sodium is at a high altitude, well above the exoplanet's atmosphere,

07:07and behaves incompatibly with the orbit of 2.8 terrestrial days of WASP-49b.

07:15These clues strongly suggest that it comes from a distinct body,

07:20probably an active volcanic moon.

07:23In addition, WASP-49b and its high star are essentially composed of hydrogen and helium,

07:29making the presence of such a cloud of sodium even more unusual.

07:34The amount of sodium released, more than 100,000 kg per second,

07:39would betray the presence of an exceptionally powerful volcanic source.

07:44If the existence of this exolunum is confirmed,

07:48it would be the very first discovery of a volcanic exolunum.

07:52In our solar system, Io remains the reference star for the study of volcanic moons.

07:58Recently, the Juno probe of NASA has captured some of the closest images of Io

08:04since the Galileo mission, carried out more than 25 years ago.

08:09The intense volcanic activity of this moon results from the warming by tidal effects

08:14caused by the gravitational attraction of Jupiter and neighboring satellites such as Europe.

08:19This game of force creates enormous internal frictions,

08:22releasing the heat that continues to feed Io's volcanic eruptions.

08:27One of Juno's most striking recent discoveries

08:30is the appearance of an unknown volcano south of Io's equator.

08:35These clichés reveal a vast complex volcanic region,

08:39stretching over about 180 square kilometers.

08:44The most surprising thing is that no trace of this volcano

08:47appeared on the images captured by Galileo in 1997.

08:52This formation developed near the Cane Hechili volcano, already listed.

08:58According to researchers, the emergence of this structure

09:01illustrates the dynamic evolution of Io's surface.

09:05The majority of volcanoes are concentrated in its equatorial region,

09:09where tidal forces exert their maximum influence.

09:13The most violent eruptions release suffocating gas clouds

09:17and give birth to lava flows.

09:20These phenomena cover Io with multicolored deposits, rich in sulfur.

09:24An image taken by JunoCam at about 2,500 km

09:28reveals Io under striking lighting,

09:31illuminated by the solar light reflected by Jupiter,

09:34offering a spectacular view of its volcanic landscape in perpetual mutation.

09:38Although these observations provide precious details,

09:41Io's volcanism retains many mysteries.

09:44Scientists wonder in particular about the influence of warming

09:48by tidal forces on the Moon's internal structure

09:51and the possible presence of an ocean of underground magma.

09:54They also seek to understand the mechanisms

09:57that trigger the different types of eruptions,

10:01and the way in which volcanic gases

10:04model Io's thin surface and atmosphere.

10:07Io's study of volcanic moons

10:10has the potential exolune of WASP-49b.

10:13It makes it possible to better understand

10:16the influence of tidal forces on volcanic activity.

10:19On frozen moons such as Europe,

10:22this phenomenon maintains liquid oceans under the surface,

10:25offering a framework conducive to the emergence of life.

10:29On Io, however, the absence of oceans

10:32transforms its forces into a powerful volcanic engine.

10:35If volcanic exolunes really exist,

10:38like those that could orbit around WASP-49b,

10:41their discovery may help us to sense

10:44other volcanic bodies across the galaxy.

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