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Mars_B4_Moon

Member

Registered: 2006-03-23

Posts: 9,776

Life on Ariel and/or Miranda?

Could Astrobiology exist in Ice-Giants?

Two of Uranus’ Moons May Harbor Active Oceans, Radiation Data Suggests
https://www.jhuapl.edu/news/news-releas … cean-moons

The team suspects the particles arise from Ariel and/or Miranda through either a vapor plume similar to that seen on Enceladus or through sputtering — a process where high-energy particles hit a surface, ejecting other particles into space. “Right now, it’s about 50-50 whether it’s just one or the other,” Cohen said.

Regardless, modeling suggests the energizing mechanism would be the same: A constant stream of particles flows from the moons into space, where they create electromagnetic waves. Those waves accelerate some small fraction of the particles to energies that LECP could detect. This process, the team believes, kept the particles seen by LECP so narrowly trapped.

However, with only a single observation of the region and no data about the composition of the plasma or measurements of the full range of electromagnetic waves within it, Cohen noted, there’s no way to definitively determine the source of the particles.

Yet scientists have already suspected Uranus’ five largest moons — Ariel and Miranda included — may have subsurface oceans. Voyager 2 images of both moons show physical signs of geologic resurfacing, including possible eruptions of water that froze on the surface.

“The data are consistent with the very exciting potential of there being an active ocean moon there,” Cohen said. “We can always do more comprehensive modeling, but until we have new data, the conclusion will always be limited.”

Triton of Neptune is also of interest to scientists, no Ocean but it is the only large moon in the Solar System with a retrograde orbit, an orbit in the direction opposite to its planet's rotation on its surface a world of Frozen Nitrogen, water-ice crust, an icy mantle with metals underneath, few craters, an active world but cryovolcanic and tectonic terrains. Triton is thought to be too cold but Ariel and Miranda might be active? Uranus and Neptune are now often classified in the separate category of ice giants look at exoplanets we have other categories like Moons which might harbor life, Super-Earths smaller than Neptune,  the super-Neptune category a planet that is more massive than the planet Neptune, exoplanets described as being around 5–7 times as large as Earth with estimated masses of 20–80 Earth but smaller than Gas-Giants or 'Hot Jupiters'. Due to Uranus's near-sideways orientation, only Miranda's southern hemisphere was visible to Voyager 2 when it arrived, it is believed to have a viscous, lava-like mix of water and ammonia, which freezes at 176 K (−97 °C), or perhaps ethanol. During its flyby of Neptune's Moon Triton, Voyager found surface temperatures of 38 K (−235 °C). The super-Earth exoplanet category is an extrasolar planet with a mass higher than Earth's, but below those of the Solar System's ice giants.

Some other past discussion on newmars

'Moons of the solar system'
https://newmars.com/forums/viewtopic.php?id=10085
NASA eyes nuclear-powered rocket
https://newmars.com/forums/viewtopic.php?id=1988
Neptune Trojans
https://newmars.com/forums/viewtopic.php?id=4736
unmanned probes to Uranus & Neptune?
https://newmars.com/forums/viewtopic.php?id=4472

Last edited by Mars_B4_Moon (2023-03-19 11:36:13)

Mars_B4_Moon

Member

Registered: 2006-03-23

Posts: 9,776

Re: Life on Ariel and/or Miranda?

New NASA research suggests four of Uranus’ largest moons, some named for Shakespeare characters, likely contain an ocean layer between their cores and icy crusts.

https://twitter.com/NASASolarSystem/sta … 7365644288

Calliban

Member

From: Northern England, UK

Registered: 2019-08-18

Posts: 3,794

Re: Life on Ariel and/or Miranda?

B4, that is an interesting discovery.  It is also worth noting that at the time that the solar system formed, common rocks had much higher abundance of potassium-40 and uranium-235 and these bodies would have retained some heat from their accretion.  Liquid water oceans may have been possible on much smaller bodies in the distant past.  If we go poking around in the frozen mud of most KBOs, we may find micro-fossils of long extinct micro-organisms.  Worlds like Mimas, Dione, Tethys, etc, may be lifeless today but may have evolved life earlier in the history of the sol system. In other star systems, with higher initial abundant of radionucludes, life could evolve in much smaller bodies.

One interesting question.  If intelligent life had evolved on a KBO or moon earlier in the solar systems history and become space faring, only to die out later or colonise the stars, would we find evidence of them today?

We have talked about creating ice covered oceans on KBOs on the terraforming board.  If an artificial fusion or fission based power source can provide a source of heat and light, even quite small bodies down to 50km is diameter could be provided with habitable oceans.  It is a convenient place to dump waste heat as well.  In the future, human habitats on the surface of KBOs couod be provided with food from oceans beneath KBO icy shells.

Last edited by Calliban (2023-05-15 11:46:48)

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"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."

Void

Member

Registered: 2011-12-29

Posts: 7,824

Re: Life on Ariel and/or Miranda?

I am currently more interested in the inner solar system, but this has shown up.

https://www.geekwire.com/2023/microsoft … nationally.
Quote:

Microsoft and Helion want to build the world’s first fusion plant and seize energy’s ‘Holy Grail’
BY LISA STIFFLER on May 10, 2023 at 6:00 am

Something like the above, might work out.  I have seen one opinion that solar could be cheaper in the future, but for places where solar does not make sense, developing the outer solar system and the "Way out", may become real.

And I guess that might give eventual answers about alien life or panspermia.

Done

Last edited by Void (2023-05-15 12:36:39)

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Mars_B4_Moon

Member

Registered: 2006-03-23

Posts: 9,776

Re: Life on Ariel and/or Miranda?

Uranus: Time to Boldly Go
https://eos.org/features/uranus-time-to-boldly-go
Scientists say now is the time to unlock the secrets of Uranus and suggest a low-cost, low-risk way to do so.

“Uranus and Neptune remain the two unexplored planets in our solar system, each with its own exciting system of moons, rings, complex magnetosphere, and dynamic atmosphere,” said Amy Simon, a planetary scientist at NASA Goddard Space Flight Center in Greenbelt, Md. Of the two, Uranus is closer and therefore more easily reached.

A group of planetary scientists and engineers designed a mission concept called the Uranus Orbiter and Probe (UOP) and has proposed the mission to NASA for review. The mission would deploy an atmospheric probe shortly after arrival, tour several moons, and then settle into orbit for 4.5 Earth years. The most recent planetary science and astrobiology decadal survey evaluated this mission as low risk, relatively low cost, and high reward.

It takes a lot of time and energy to travel to Uranus, said Athena Coustenis, a planetary scientist and director of research at Centre National de la Recherche Scientifique in France. An efficient flight path would take a spacecraft past Jupiter to gain some energy through a gravitational slingshot. A launch window in the early 2030s would provide the necessary planetary alignment, but there would be launch opportunities for several years following, too.

Mars_B4_Moon

Member

Registered: 2006-03-23

Posts: 9,776

Re: Life on Ariel and/or Miranda?

Unwrapping Uranus and its icy moon secrets
https://www.spacedaily.com/reports/Unwr … s_999.html

The moons, mostly named after literary characters from the writings of Shakespeare and Pope, are primarily made of frozen mixes of ice and rock. Five of the moons are particularly compelling. Miranda, Ariel, Umbriel, Titania and Oberon are all big enough to be spherical and treated as miniature worlds in their own right.

During its flyby, Voyager 2 took low-resolution images of the moons' southern hemispheres. (Their northern hemispheres, still unseen, remain one of the major unexplored frontiers of our solar system.) Those images include photos of ice volcanoes on Ariel - a tantalizing hint of past geological and tectonic activity and, possibly, subsurface water.

The possibility of oceans and life
Which leads to one of the most exciting parts of the mission: Many planetary scientists theorize that Ariel, and perhaps most or all of the other five moons, may be an ocean world harboring large, underground bodies of liquid water miles beneath the solid, icy surface. Finding out whether any of the moons have oceans is one of the major goals of the mission.

This is one reason why an orbiter would probably carry a magnetometer - to detect the electromagnetic interactions of an underground ocean as one of its moons travels through Uranus' magnetic field. Instruments to measure the moons' gravitational fields and cameras to study their surface geology would help, too.

Liquid water is an essential requirement for life as we know it. If oceans are detected, scientists will then want to look for other ingredients for life on the moons - such as energy, nutrients and organic matter.

Mars_B4_Moon

Member

Registered: 2006-03-23

Posts: 9,776

Re: Life on Ariel and/or Miranda?

‘Once in a lifetime’: UK and European space scientists urged to join Nasa mission to Uranus

https://www.theguardian.com/science/art … -to-uranus