A Planet Here Today and Gone Tomorrow

The universe is certainly more alive than we ever expected it to be. Lots going on. Interesting considerations in the essay reproduced below, from Dr. Ian Miller for (the lack of life) inside Europa… (Well then so much the better, we can engineer our own… Having the largest ocean in the solar system below our feet will help in many ways…)

At least one asteroid to asteroid collision was observed in the solar system: we have a movie of it!

https://www.nytimes.com/2019/11/26/science/asteroid-belt-impact.html?action=click&module=RelatedLinks&pgtype=Article

The New York Times, in The Case of the Disappearing Exoplanet (Fomalhaut b was one of the first planets around another star to be directly imaged by telescopes. Some astronomers now say it was a cloud of asteroid debris.)… showed the movie of the apparition and disappearance of the Fomalhaut b “planet”, from Hubble pictures. It really looks like an explosion…

Exoplanet PSEUDO Formahaut b

This is the pseudo-exoplanet, lower right, circa 2006, as seen by Hubble High Resolution. The star itself is hidden by a (man made device inside Hubble). The dust ring is fully visible. The movie of the situation shows the yellow dot expanding in a big orange, then deep red explosion…

And the cloud took a decade to dissipate, just as theory predicts.

Regarding the essay of the honorable Dr. Miller reproduced below, I beg to differ on one point, as I don’t see why standard gravitation theory doesn’t predict planet accretion (but that’s science in accretion: theories differ…)

First the mass of a dust cloud could be many solar masses. It collapses under its own gravity. At it does, the slightest rotation is converted, through angular momentum conservation into a massive rotation of a disk… This star system formation theory comes from Laplace. The same rough picture applies to form galaxies… and planets! If a cloud shaped as a doughnut is the mass of Jupiter, even if in orbit, around a star, it will end up collapsing on itself, from some irregularity… and the rotation on itself, in the correct sense will be generated from the orbital motion (as observed!… mostly).

The cloud around the star doesn’t have to be even, nor does the disk then, hence haphazard planetary mass distributions (as observed). However one would expect more mass towards the center… Thus Jupiter-like planets to be towards the center (as observed: the “hot Jupiters”)… As the central mass becomes a star, radiation pressure enters the mix. So one would then expect many of the hot Jupiters to be torn apart, losing their gas 9except for hot Jupiters which are massive enough!), leaving rocky planets behind (as observed), or then that rocky planets would form towards the interior from sinking of the densest elements (as observed).

Right, these are contrary, alternative scenarios. However, stars are not all the same, thus neither are radiation pressures: a tiny red dwarf (75% of stars) is nothing in common with a blue supergiant (a future supernova).

In any case, exciting days. Instead of propping up the useless and degenerate non-essential economy, the frivolity of which the Corochinavirus is thoroughly demonstrating, to my great satisfaction. Instead, humanity should do something really useful, and build a 200 meters across telescope… there are lots of questions about the Centauri system, including that of the exoplanet closest to Earth, apparently a sort of super-earth… Is it alive? Inhabitable? First we should find out how big it really is…

ianmillerblog

Or, a record for the biggest thing lost! Or, to loose your car keys is careless, but to lose a planet??

As some readers will know, I have my own theory of how planets form from the dust of the accretion disk around stars. The dust is actually micron sized, and finer than an average smoke distribution, and as the gas falls into the star, it gets hot, its potential energy lost being converted to heat, and when it gets hot enough it glows. Of course, it also glows by scattering light emitted by the forming star hence we observe those disks. Standard theory assumes planets form through gravity. The problem here is gravity is far too weak to aggregate this dust, so the standard theoryassumesthat somehow it forms planetesimals and there is an even distribution of these out to about 32 A.U. (one A.U. is the Earth-Sun…

View original post 559 more words

4 Responses to “A Planet Here Today and Gone Tomorrow”

  1. ianmillerblog Says:

    Gravitational collapse to form planets has been proposed, but it works best further from the star. There are some planets that have been detected up to 1,000 A.U. from the star and these may well have formed like that (or they may be just stray things that drift in.) The distances are so great we cannot be sure they are gravitationally bound to the star. The other problem with it is unless it stars late, why does it just give a planet? It is a highly probable mechanism to form double stars, though, and they are quite common.

    Liked by 1 person

  2. ianmillerblog Says:

    on May 2, 2020 at 11:32 pm said:
    I was unaware there had been an asteroid collision, so thanks, Patrice. As for the rest of what you write, there is enough material there for several posts, but my primary feeling is there is too much space for planets to grow fast enough by collisions of equal-sized bodies. There will be such collisions but I believe the growth is mainly through a large object sweeping up everything it encounters as the gas drifts inwards. The first calculations by Safranov had it taking at least a billion years to get to Neptune, (but the gas would have long gone.) Recent observations have shown massive planets that have grown withing 2 My, and no simulations can approach that rate of formation from equal-sized collisions.

    Like

  3. pshakkottai Says:

    Ancient Surya Siddhanta which came after the Vedas predicted planetary diameters using simple scaling rules for the dust condensation in

    https://patriceayme.wordpress.com/2017/10/28/creative-thought-is-all-over-the-place-and-out-of-this-world-or-is-not/#comment-71513

    The diameters of gaseous planets Jupiter and Saturn are surprisingly good.

    Like

What do you think? Please join the debate! The simplest questions are often the deepest!

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s


%d bloggers like this: