What fraction of the time are they due to single white dwarfs and companion stars? And then which results in the brightest and most powerful supernova? Figuring out those kinds of things will then help us measure dark energy more efficiently. We've seen that supernovae in high-mass galaxies behave differently than supernovae in low-mass galaxies. We don't know why that is, and that will be one of the challenges of the next ten years of supernovae research. The answer will be integral for dark energy research. TKF: What have been the big breakthroughs in understanding this type of supernova?
Recognizing that multiple paths lead to these events, I think, has really opened up the theoretical ideas about how these explosions unfold and been extremely healthy and exciting for the field. We would find it, then we'd all go home and that would be the end of it. But now we're starting to see that there are many different ways to make a Type Ia supernova. Laura Chomiuk's radio wave astronomy research uses the Expanded Very Large Array to study the stellar conditions that lead to Type Ia supernovae. Credit: Laura Chomiuk.
For example, in and we had a couple of Type Ia supernovae explode in nearby galaxies. Because these explosions were so close and bright, we were able to perform detailed tests on them. We've also gotten really good astronomical surveys up and running that are scanning the whole sky, so we've been able to discover Type Ia supernovae earlier, basically right after they explode.
Then we have satellites that can go and get ultraviolet and x-ray observations right away. So we can probe all wavelengths of light at once now. Lastly, there have been advances in computing that allow us to create three-dimensional simulations of supernovae to test out theoretical models. So it's not just new capabilities but all these new capabilities working together that are allowing us to make such progress.
We're developing new capabilities that are leading to big, big jumps in our understanding of whatever it is we're studying, including supernovae. TKF: Lars and Dan, as theorists, could you describe the feeling you get when your models are borne out by observations? Daniel Kasen's research in theoretical and computational astrophysics focuses on supernovae, neutron star mergers and other energetic, short-lived cosmic events.
Credit: Daniel Kasen. As a theorist, you're constantly developing ideas that seem a bit distant and abstract, almost like science-fiction. Then, suddenly, observers actually go out and bring home hard data. Historically, most theoretical work has not been strongly tested until long afterwards.
Astronomy theorists are quite often, therefore, behind the observers in having a coherent picture of what is in fact out there in space. When we get ahead of the observer is when it's the most fun to be a theorist! TKF: A perfect example of theory preceding observation is Dan's theoretical work. He proposed that material ejected by a Type Ia hits a companion star and produces an ultraviolet pulse. Andy, as well as some other astronomers, has now observed those pulses. Dan, how did you come up with this theory? And then Andy, how did you and your colleagues run with Dan's ideas?
People have discussed over the years whether companion stars could survive the blast from a nearby supernova explosion. But nobody had asked, "What would it look like to actually see that happen? So I did a back-of-the-envelope calculation to estimate how hot that collision would be, how bright it might be, and so on. Surprisingly, the collision turned out to be bright enough to be seen on Earth.
"Dark Red #6" preview
That gave the observers an idea of what to look for. Dan's work is not just some made-up model. It's something you can really sink your teeth into. Credit: Andrew Howell. The first time I heard Dan describe his theory, it just blew me away. I remember thinking, "Whoa, this is incredible—we can totally test this out.
We quickly figured out, though, that the observations of supernovae we had on record weren't good enough. That realization has driven a lot of our subsequent telescope and observation proposals, like the robotic telescopes that Lars mentioned, which capture supernovae right after they occur rather than days or weeks later. As new surveys have captured hundreds of supernovae, it's been great to finally see Dan's theory play out.
But within each of those ideas, we are still not sure how the supernova goes off; how does the star gets ignited? Does it always explode or might it instead collapse into a superdense neutron star? Is the first spark of the explosion lit at the center as an accreting white dwarf is compactified, or is the star lit from the outside in, by igniting a fuse of accreted gas at the surface?
To try to connect your theory to observations, you have to use some pretty sophisticated, multi-dimensional computer simulations. We are still trying to draw those lines between the various theories and data. I would say we're still not there, but we're getting closer. TKF : What observations could plug these remaining gaps in our knowledge? CHOMIUK: We've seen supernovae go off very close by in other galaxies, but we would really love it if one went off right in our galactic backyard, here in the Milky Way galaxy. There's a crisis in supernova rates.
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No mechanism really accounts for how many supernovae we see. Figuring that out will require a lot of theoretical work, and observations will help get us there. TKF: Does anyone have a sinking feeling that there could be three or more scenarios that explain Type Ia supernova? But within each of those scenarios there are many different pathways, so to speak.
Take the two white dwarfs scenario. There are several different ways to initiate the supernovae. I was ready to give up on What a concept, read the story and watch short videos online that enhance the story. I was ready to give up on this book early but I really hate having books in my abandoned list so I continued reading. The story is full of holes and there are things that are never explained, we never find out where the killer gets his money for example. The online videos were barley worth the effort to watch, the directing was extremely bad, the acting was fair with some known actors in small parts, the problem was the information.
Some of the videos show you information before it appears in the book and some of them are from scenes that are not even in the book. I had hoped that the videos would give hints and clues that would add to the story but you could read the book without going online and not miss anything.
Once I decided that I was not going to abandon this book, I discovered that everything in the book didn't have to be perfect for me to enjoy it. When I read stories about people visiting alien worlds, I have to suspend reality to a certain degree, I had to do the same with this book before I could enjoy it.
Bloodlust Re-Ignited in DARK RED #6 Preview
Once I got past a few of the boring cliche's, I realized that despite myself, I was completely caught up in the story and couldn't wait to get to the next video. Level 26 was a weird experience for me. After reading the jacket cover, I thought this was a fantastic idea and I couldn't wait to start reading it.
After reading the first four chapters I was ready to abandon Level 26 because it didn't seem to have anything new in the storyline worth the effort to read it. Now that I have finished Level 26, I think it was a pretty interesting experience and I will probably continue reading the trilogy. Sep 08, Bridget rated it it was amazing. Currently there are 25 levels to categorize serial killers. One is someone who just stumbles into killing. Twenty-Five would describe the sadistic psychopaths who find pleasure in suffering.
Now imagine that one person has become even more evil than the serial killers you've heard about in the past? Imagine someone who has absolutely no compassion, no feeling, not even a soul. A person lacking all these characteristics is out there and because he doesn't seem to show any of the "normal" traits o Currently there are 25 levels to categorize serial killers.
A person lacking all these characteristics is out there and because he doesn't seem to show any of the "normal" traits of a killer it impossible to catch him. This psycho has a name. It's Sqweegel. The one person who has the ability to catch this criminal is Steve Dark. In a state of mourning, thanks to the psycho, Dark is through with law enforcement and wants no part of the chase. But when the lives of his friends at the department are threatened, Dark decides to step in again. Will he be able to stop this madman before several other murders take place?
Or will the world live in fear of Sqweegel until the day they die? To sum up this book in one word, is impossible. But for some reason, I'm the type of person that loves the impossible and do everything I can to try and make it possible.
Monstrous Cosmic Gas Cloud Set To Ignite The Milky Way
So as you've probably guessed, I've been doing some hardcore thinking I know what your thinking, and yes it caused a massive headache, LOL so as I pondered and looked through the dictionary no I didn't really look in the dictionary but shhh, it's our secret and the word that jumped out at me was: WOAH! Yes, all caps and an exclamation point. This is really difficult to review.