Category: type Ia supernova

These Are The 6 Different Ways To Make A Super…

These Are The 6 Different Ways To Make A Supernova

“Yet, if you cross a certain mass threshold, you overcome that quantum barrier, and that triggers a runaway fusion reaction, destroying the white dwarfs and leading to a different class of supernova: a thermal runaway supernova.

So, we’ve got core collapse supernovae and thermal runaway supernovae. Does that mean that there are only two classes?

Hardly. There’s more than one way to make both a thermal runaway and a core collapse supernova, and each mechanism or method has properties that are wholly unique to it. Here are the six ways to make a supernova, starting with the least-massive trigger and going up from there.”

So, you’ve got a star, and you want to trigger a supernova with it? Great! Every star that ever gets made in the Universe has the possibility of going supernova. If your star is born with more than about 8 solar masses, it’s practically an inevitability that a supernova will ensue, and that it will be a core-collapse supernova at that. But there are four independent ways to make that happen, and only one of them is the conventional way you probably think about it. If your star has less than 8 solar masses, though, it ends its life in a white dwarf, but that’s not necessarily the end. White dwarfs can gain enough mass, through two different known mechanisms, to someday go supernova as well.

There are six different ways to make a supernova, and each one is spectacular. Which one is your favorite?

Why Cosmology’s Expanding Universe Contr…

Why Cosmology’s Expanding Universe Controversy Is An Even Bigger Problem Than You Realize

“The question of how quickly the Universe is expanding is one that has troubled astronomers and astrophysicists since we first realized that cosmic expansion was a necessity. While it’s incredibly impressive that two completely independent methods yield answers that are close to within less than 10%, the fact that they don’t agree with each other is troubling.

If the distance ladder group is in error, and the expansion rate is truly on the low end and near 67 km/s/Mpc, the Universe could fall into line. But if the cosmic microwave background group is mistaken, and the expansion rate is closer to 73 km/s/Mpc, we just may have a crisis in modern cosmology.

The Universe cannot have the dark matter density and initial fluctuations that such a value would imply. Until this puzzle is resolved, we must be open to the possibility that a cosmic revolution may be on the horizon.”

Ever since we first learned that the Universe was expanding, scientists have worked hard to measure just how fast that expansion rate is. From that, combined with what makes up the Universe, we can learn how old the Universe is and what it was like in the past, as well as what it’s fate will be in the future. Yet the two groups that make independent measurements of that rate, from the cosmic microwave background and the cosmic distance ladder, have gotten inconsistent results. If the distance ladder team has made a mistake, everything will be fine with cosmology. But if that team is right and the microwave background team is wrong, there should be a crisis coming.

Why is that? Come find out why the biggest controversy in modern cosmology might be an even bigger problem than almost everyone realizes!