Tag Archives: astronomy

It Seems the Idea of Dark Energy May Have Been Premature, After All

I ran across this today:

Is Dark Energy a Real Thing? Maybe Not, A New Study Suggests

According to prevailing cosmological theories, the universe is expanding, but not at a constant rate. As the universe gets older, its growth seems to accelerate over time, something that would be impossible without some sort of extra energy being added to the overall system. Dark energy, the theory goes, accounts for nearly 70 percent of all energy in the observable universe.

But a new study from Oxford has called dark energy’s existence into question, saying that the data is flawed or based on observations that previously assumed that dark energy was already a universal constant. If this is the case, then scientists may have to go back to reevaluate their understanding of the universe and how it works.

Dark energy and dark matter are two things that have troubled me for a long time about the current state of astronomy.  Not only is dark energy supposed to be 70% of all energy in the universe, but dark matter is supposed to be 96% of all matter in the universe – or 24 times the amount of matter we can actually detect.

These are two things that cannot be seen or felt or heard or sensed, even with our best instruments (which are extensions of our five senses, in a very real sense). To me, there was something crooked in Denmark, some way that the astronomers had gone down the rabbit hole and had misjudged something or assumed some things that would end up being not true. Continue reading

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Comments on the formation of asteroids/meteoroids…

It is very often said in popular articles about meteors, comets and asteroids that they all represent the material that is left over from the very beginning of the solar system.  It is further said – often – that these bodies “accreted” from smaller material flying around in what is called the “planetary nebula.” That means that they kept gravitating toward each other until the collection of material became an asteroid or a comet.

I dispute both of these assertions by astronomers.  Why?   Because I think that they call up accretion as a mechanism, without ever asking what happens during accretion or if the temperatrues and pressures and impact forces available can actually do what they say accretion is or is doing.  When one reads about how asteroids or planets form, the say “accretion” and then go on to what happens after accretion, without really ever having to explain it.

Why do I think any of this?  Because there is insufficient gravitational force between small objects in space.  There is also insufficient pressure in space to turn molecules of metals into solid chunks of metal, nor to alloy them together.

Let me start with a few definitions.  I am putting them at the bottom here, so that I don’t lose the reader at this point with boring stuff.

I just looked at the list of elements and molecules present in the most studied meteorite in the world, one called the Allende meteorite.  The list runs to 17 main components and 57 elements.  That means over half the Periodic Table is represented in ONE meteor.  That is one helluva cocktail.

The Allende meteorite is a “carbonaceous chondrite” as opposed to a mostly iron-nickel meteor.  It still has plenty of iron and nickel, but not a LOT. Carbonaceous chondrites represent about 4% of all meteorites found so far. 86% of the total are stony chondrites.  The Allende meteorite weighs about 2 metric tons and is also the heaviest and biggest meteorite yet found.  It looks like this:

The Allende meteorite, showing many chondrules, which make it a chondrite

All those chondrules, plus the matrix that binds them together, contain all those compounds and elements I mentioned.

The funny thing is that some of the materials in the meteorite are garnet, peridotite, and olivine.  There are more, but those are important.  You see, peridotite is found where diamonds are found and are created by much the same forces – high temps and high pressures.  Olivine also needs pressures around 24 gigapascals (gP), about 3.9 million pounds per square inch (psi), plus high temps, about 2,000°C (nearly 4,000°F).  Garnet is a semiprecious stone that also takes a LOT of pressure and temperature to form. Continue reading