We once more return to the question of how planets are formed. In the video I did on the system that
was rules by order and chaos we saw a system that had many sub neptune class planets and wondered
about how they might have formed and why their locations did not match the conventional theory.
In a new piece of research published astronomers have attempted to link data from different surveys
to come to a rather remarkable conclusion regarding these sub neptune class worlds
and how they might have been formed.
Let dive in and find out what else this analysis might tell us
The largest planets we find are mostly composed of gas and ices
like hydrogen, helium, water, ammonia, and so on.
It is believed that at their heart there is a rocky core under extreme pressure.
Astronomers have long speculated that if a giant planet were subject to enough radiation from its
parent star, eventually it would be stripped of its gaseous atmosphere, leaving only its
rocky core. The problem was that no one knew how long this process would take, it might
take the entire age of the universe to happen and therefore it would not have happened yet.
By combining two surveys they think they may be able to shed new light on this problem.
The first survey is the Kepler mission which so far has found
thousands of exoplanets orbiting other worlds, including super earths and sub neptunes.
The other survey is the Gaia mission which provided an essential ingredient
to measuring the sizes of the planet hosting star.
Combining size and stellar colours allows them to determine the relative ages of stars.
What they discovered was an interesting trend which showed that stars which output
higher amounts of starlight amd which were considered younger tended to have more sub
neptune worlds compared to those which they would consider older.
Which tended to have more super earth worlds and less sub neptune ones.
They speculate that the link here is that the starlight is stripping the gas away
from these planets leaving behind only the rocky bodies. This could happen in
as little as 1 billion years rather than the entire age of the universe.
Now let's take a little step back here. If stars are indeed electrically powered
there is a different relationship that this shows up.
Larger more energetic stars appear to have more sub neptune class worlds compared to
stars under a more normal load or even those which are underpowered.
So why might this be?
We have previously speculated that the larger gas giants might have captured brown dwarfs
but that maybe the sub neptune class worlds were ejected from the star itself.
It would therefore make sense that stars which are under a higher electrical stress
would see a greater number of sub neptune worlds.
But why would a more normally powered star have less sub neptune class worlds?
It is important to realise that their data only shows a correlation not the actual change taking
place. They determine the age of the star using metallicity, temperature and colour
and then choose a cutoff of 1 billion years. Those marked in green are considered younger,
those in purple older. We do see a general trend that the
‘older’ stars seem to be larger at a given temperature compared to the younger variant.
In the electric universe stars are born in z-pinches
and it's a reasonable assumption that these would tend to be born in a higher energy state
and it is unlikely that a star would be created in an underpowered state.
So is it possible that the reason we see less sub-neptunes
in more normally powered stars is for the same reasons the mainstream gives here?
Could these sub-neptunes which are born in a highly energetic system over time have their
atmosphere stripped away meaning that those that over time wander or receive less power would by
this fact be older and hence their sub neptunes would have had more time to be stripped away?
Another simpler way of looking at this data is to consider the supposed age difference between
what they consider young and old is not that much. So where they are seeing less sub neptune planets
these are stars which simply are less stressed and would therefore not have
produced sub neptunes through ejection. This does however leave the question about why there
would be more giant earths around these types of stars compared to the more stressed stars.
Again here we need to be cautious as the only way they can tell the difference between a sub neptune
class world and a super earth is the effect it has on the star in terms of the dimming of the light.
This tells them a size and the time period tells them an approximate radius from the star.
The redshift then tells them how much wobble this causes on the
star and this gives them an approximation for the mass of the star. More massive planets will
cause a greater wobble on the star. They are not directly observing the planets themselves
When we examined the origin of an expanding earth I covered one concept where a gas giant could be
stripped of all its gas leaving a rocky core. This rocky core would be under a lot less pressure and
would therefore have to expand. In a new analysis of both Gaia and Kepler data some astronomers are
proposing sub neptune worlds may be stripped of their gasses by the young star leaving only
a rocky super earth and that this process could occur relatively speaking quite rapidly. Could
this account for an expansion mechanism?
The problem here is that it would only account for this on some of the world
and would not explain why we see it on the moons of our outer solar system.
Returning to the piece I did on the system that was ruled by order and chaos.
Could this theory explain what we saw there? Just a quick recap they thought that there was
a major problem with the order of the density of the system and that there was a giant earth
after a sub neptune world followed by another sub neptune world. You would certainly expect
the sub neptune worlds to be turn into rocky planets from the centre outwards.
So closest to the star first. We see that in the first few planets but then end up with this out of
order. It is possible that some sub-neptune worlds have more gas so may take longer to
burn off compared to others. Of course it is equally possible that what we are seeing in this
relationship does not directly relate to the star stripping the planets of gas but more to do with
the electrical environment of the star itself and hence what types of worlds it might have spawned.
Buried in this is data that I think could prove useful in trying to understand how planets form
around star systems. In the EU model planets are ejected. So star systems with planets
that are close are likely to be ejected from the star. More distant planets are generally
captured subsequently and in this capture process it must cause a respacing of the orbits
and a deflection of some of the bodies closer in.