Planets Surviving Without A Host Star?

[hazelm]

https://www.sciencedaily.com/releases/2019/05/190514115831.htm?utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+sciencedaily%2Ftop_news%2Ftop_science+%28ScienceDaily%3A+Top+Science+News%29

 

According to a study by astronomers at Warwick University, small rocky planets with densely packed elements just outside the destruction radius might survive the death of their host star.

 

Q.  What then?  Can planets survive with no star to orbit and interact with?  Is that what "exoplanets" are - planets drifting alone in space?  Could there be life on these survivors? 

[hazelm]

Without a sun its going to get very cold on the surface of the planet. Likely it will be frozen solid, but perhaps with a bit of Volcanic activity, it might be warm enough in places for life to survive. Eventually it could drift into another solar system and perhaps collide with other planets. Venus for example spins the opposite way to the rest of the planets, https://en.wikipedia.org/wiki/Venus It is thought that Mars and Earth both have had massive collisions in their early history, and is where the moons come from. https://medium.com/starts-with-a-bang/what-was-it-like-when-venus-and-mars-became-uninhabitable-planets-a8a1832104dc 

Thank you.  I was thinking I have read about drifting planets but thought maybe I'd dreamed it.  I had not thought of volcanic activity.  Stored up heat in what we eventually call lava?  I once went looking for a good book about volcanoes- what causes them to form.  Not so much activate ss their source and what forms that.  All I found were children's books.  Who knows.  Maybe one of them tells but I hoped for more.

 

But, yes, we need heat for life - on Earth, at least.  We can't be sure on some faraway drifting planet.  Thank you.

[hazelm]

Perhaps you were not dreaming :)

 

https://www.space.com/15023-warp-speed-planets-light-speed.html

I wonder about that statement about any possible life on such a planet having a wild ride.  If I remember rightly, our own planet mover pretty fast but we, as riders on it are not aware of the speed.  True?  Thank you for the notice.  Interesting.

[fahrquad]

Exoplanets are planets outside of our solar system.  In general they are detected orbiting other stars by way of their gravity causing a small wobble to the parent star(s).  There are rocky masses wandering about the universe that may have accreted from smaller objects and there may be rogue planets that were ejected from a solar system from the gravitation disturbance of a passing star.  A star the size of our sun or smaller would most likely end its life as a brown dwarf, so it would not eject any of its mass beyond its solar system and no planets would be ejected.  Our sun will vaporize Mercury and Venus, and if Earth survives it will be nothing more than a charred cinder.  The polar regions of Mars and the moons of Jupiter and Saturn might look downright hospitable by then.  All bets are off with a higher magnitude star since it will explode more forcefully and vaporize any inner planets.

 

 

 

https://en.wikipedia.org/wiki/Future_of_Earth

Edited May 21, 2019 by fahrquad

[fahrquad]

https://www.sciencedaily.com/releases/2019/05/190514115831.htm?utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+sciencedaily%2Ftop_news%2Ftop_science+%28ScienceDaily%3A+Top+Science+News%29

 

According to a study by astronomers at Warwick University, small rocky planets with densely packed elements just outside the destruction radius might survive the death of their host star.

 

Q.  What then?  Can planets survive with no star to orbit and interact with?  Is that what "exoplanets" are - planets drifting alone in space?  Could there be life on these survivors? 

 

The host star may be dead, as in no longer supporting nuclear fusion, but the mass (and gravity) is still there so the planets will not drift away.  Life would probably not survive the extinction of the star, but if it did then things would get cold pretty quick.

[exchemist]

The host star may be dead, as in no longer supporting nuclear fusion, but the mass (and gravity) is still there so the planets will not drift away.  Life would probably not survive the extinction of the star, but if it did then things would get cold pretty quick.

Yes. The planet would cool down until its surface was at the temperature of the the cosmic background, 2.7K (unless there were some source of internal heat from the planet itself, in which case it might be a few degrees warmer). No chemical reactions would proceed at this temperature, so it is fairly safe to say that no life would continue. 

[GAHD]

https://en.wikipedia.org/wiki/Rogue_planet

 

Rogues are a neat thing. They'd need some form of dynamo to drive energy for any kind of life to develop or survive, like deep sea volcanoes or whatnot. I guess if it had a pair of moons to keep the geology active, or enough "natural" nuclear reactors?

[fahrquad]

Below the surface of the frozen crust life might exist. If there is still some residual temperature. Europa one of the moons of Jupiter might have liquid below its frozen surface https://www.space.com/15498-europa-sdcmp.html 

 

Life has evolved to live in extreme conditions, bacteria can live ice. Evidence of amino acids the building block of life has been found on meteorites from outer space, or perhaps due to a collision many moons ago, has come back to earth from outer space :) .

 

The cores of the moons of the gas giants are heated by the constantly changing tug of gravity.  Liquid water is known to exist on Europa, Enceladus, Ganymede, Ceres, Uranus, and Neptune...oh, and Earth.  Frozen water has been found on Mars, and is also found on comets and asteroids.  Venus may have water vapor mixed up in its hot acidic soup of an atmosphere.

 

https://en.wikipedia.org/wiki/Extraterrestrial_liquid_water#Ice_giants

Edited May 21, 2019 by fahrquad

[exchemist]

Below the surface of the frozen crust life might exist. If there is still some residual temperature. Europa one of the moons of Jupiter might have liquid below its frozen surface https://www.space.com/15498-europa-sdcmp.html 

 

Life has evolved to live in extreme conditions, bacteria can live ice. Evidence of amino acids the building block of life has been found on meteorites from outer space, or perhaps due to a collision many moons ago, has come back to earth from outer space :) .

But these amino acids are not evidence of life. In fact one reason they survive is because it is too cold for the to react with anything.

 

The subsurface temperature of a planet is more interesting, though. You are right: I quite agree there could be sources of heat as there are on the Earth which might allow life to continue underground or in a liquid solvent of some sort.

[fahrquad]

Yep, Venus has water vapor, as in 20 ppm (parts per million).  The rest of the atmosphere is nitrogen, argon, helium, neon, carbon monoxide, hydrochloric acid, sulfuric acid, hydrofluoric acid, and other nastiness.  Pressure at the surface is equal to being 3000 feet below sea level.  The probes that have made it to the surface intact have not lasted very long.  

 

Images from Soviet Venera probes before failure.

 

https://en.wikipedia.org/wiki/Atmosphere_of_Venus

https://en.wikipedia.org/wiki/List_of_missions_to_Venus

[fahrquad]

Amino acids, the building blocks of life, are easily formed with common atmospheric ingredients and conditions.

 

"In 1929 British biochemist John Haldane (1892-1964) put forth the theory that the early atmosphere of Earth contained no free oxygen. Haldane and Soviet biochemist Aleksander Oparin (1894-1980) had both suggested that all the ingredients for life existed on Earth from the beginning and that energy from the sun and some unknown process had gotten life started.

 

In 1952 American chemist Harold C. Urey (1893-1981) published an elaboration of Haldane's theory, suggesting that Earth had formed from a cold stellar dust cloud. Its early atmosphere was then roughly similar to that of the rest of the universe -- that is, mostly hydrogen with traces of other elements. Urey figured that the trace oxygen, nitrogen, and carbon would be bound with hydrogen and exist as water, ammonia, and methane. With so much hydrogen around, free oxygen could not exist (it would always get bound up with hydrogen and form water). But as time went by (lots of time), many of the extremely light hydrogen atoms escaped into outer space until the balance changed. Without an excess of hydrogen, free oxygen could exist and gradually accumulate in Earth's atmosphere.

Stanley Miller (b. 1930) was a doctoral student working with Urey at the University of Chicago, researching possible environments of early Earth. In 1953 he combined the ideas of Urey and Oparin in a short, simple experiment.

 

He reproduced the early atmosphere of Earth that Urey proposed by creating a chamber with only hydrogen, water, methane, and ammonia. To speed up "geologic time" in his experiment, he boiled the water and instead of exposing the mix to ultraviolet light he used an electric discharge something like lightning. After just a week, Miller had a residue of compounds settled in his system. He analyzed them and the results were electrifying: Organic compounds had been formed, most notably some of the "building blocks of life," amino acids. Amino acids are necessary to form proteins which themselves form the structure of cells and play important roles in the biochemical reactions life requires. Miller found the amino acids glycine, alanine, aspartic and glutamic acid, and others. Fifteen percent of the carbon from the methane had been combined into organic compounds. As amazing as discovering amino acids at all was how easily they had formed."

 

https://www.pbs.org/wgbh/aso/databank/entries/do53am.html

[hazelm]

The cores of the moons of the gas giants are heated by the constantly changing tug of gravity.  Liquid water is known to exist on Europa, Enceladus, Ganymede, Ceres, Uranus, and Neptune...oh, and Earth.  Frozen water has been found on Mars, and is also found on comets and asteroids.  Venus may have water vapor mixed up in its hot acidic soup of an atmosphere.

 

https://en.wikipedia.org/wiki/Extraterrestrial_liquid_water#Ice_giants

All true for what already exists before the planets are sent adrift because their sun died.  But isn't it a fact that all those situations were first formed by elements from that now-gone sun?  So, can life continue to exist and develop further without a sun to "feed" its planets?  If not, what happens when resources are all gone?  A long, long time period, of course.  Just asking.

[GAHD]

All true for what already exists before the planets are sent adrift because their sun died.  But isn't it a fact that all those situations were first formed by elements from that now-gone sun?  So, can life continue to exist and develop further without a sun to "feed" its planets?  If not, what happens when resources are all gone?  A long, long time period, of course.  Just asking.

Then they'd adapt or die?