The work by Gilfanov and Bogdan described in the recent Chandra Press release represents a major advance in understanding the origin of Type Ia supernovas. Here, in Q & A format, we give some of the backstory of this important discovery.
Illustration: NASA/CXC/M.Weiss
What is a Type Ia supernova?
A Type Ia supernova is thought to occur when a dense stellar remnant called a white dwarf somehow exceeds its weight limit and undergoes a thermonuclear explosion. Their peak brightness is generally greater than that of core-collapse supernovas, the class of supernova caused by the collapse of a young, massive star. Historical Type Ia supernovas such as Tycho's supernova were spectacular events, visible in the daytime by early astronomers.
http://chandra.harvard.edu/xray_sources/supernovas.html
What triggers these explosions?
The two main possibilities are the accretion scenario and the merger scenario, as explained in the press release. This work provides direct evidence against the accretion scenario in elliptical galaxies, implying that the merger scenario dominates in these galaxies. The accretion scenario is much more difficult to rule out in spiral galaxies because the presence of large amounts of cold gas and dust absorbs low energy X-rays expected from accreting white dwarfs and makes the interpretation of the data considerably more difficult.
Read the full article
-P. Edmonds, CXC
- chandra's blog
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Nice
With all these explosions occurring in space, has anyone ever seen any form of creation? Because there seems to be a whole load of exploding stars and its never ending. Robby
The new results are not
The new results are not expected to drastically alter measurements of the universe's expansion rate. But understanding how the explosions form in different environments could help astronomers make more precise measurements of the expansion rate using supernovae.
Nice Post...
The authors explain this is hard to understand if most Type Ia supernovas explode when the primaries reach the Chandrasekhar mass. One possible explanation for this mystery is that the merger scenario is an important type of trigger in all types of galaxies not just ellipticals. Since more massive white dwarfs should be found in younger galaxies, they may be able to produce brighter explosions when they merge. However, more theoretical and observational work is needed to confirm this idea.
nice post
your article "What Triggers Cosmology's Most Important Explosions?" is much informational, thanks for sharing this. Keep stuff posting like this.
Re:
According to wikipedia, the Type Ia supernova is a sub-category in the Minkowski-Zwicky supernova classification scheme, which was devised by American astronomers Rudolph Minkowski and Fritz Zwicky. And according to other shared info sources, there are several means by which a supernova of this type can form, but they share a common underlying mechanism. When a slowly-rotating, carbon-oxygen white dwarf accretes matter from a companion, it cannot exceed the Chandrasekhar limit of about 1.38 solar masses, beyond which it would no longer be able to support its weight through electron degeneracy pressure and begin to collapse. In the absence of a countervailing process, the white dwarf would collapse to form a neutron star, as normally occurs in the case of a white dwarf that is primarily composed of magnesium, neon and oxygen.
That finding has shaken the very foundations of astronomy. It takes a vast force or energy to make the universe increase its rate of expansion... a LOT of it. Where is this energy coming from?
Nobody knows.
Dark Energy
Thanks for your comment. Type Ia supernova are used to study the expansion rate of the Universe, and this expansion rate is increasing, as you point out. No one knows the source of the "dark energy" responsible for this effect, but scientists have developed some theories:
http://chandra.harvard.edu/xray_astro/dark_energy/
CXC
your article is really good
Your article is really good man
Interesting
This supernova thing interests me. I cannot remember that I have loved this topic back in gradeschool. Thanks for making this write-up, it's simple and easy to understand. I'm loving it now.
Out of my knowledge
Very difficult for me to understand the triggers, thanks a lot for the explanation :)
Truly interesting article
I was searching real hard for an article on Type Ia supernova. Found all that's required here. Would you recommend other sources for further reading.
Find Info About Type La Supernova
Just search the keyword "type la supernova" on Google, you will find many related documents and videos.
It's very interesting!
The article is very interesting and cognitive! Thanks a lot!
I forgot to tell you that,
I forgot to tell you that, at the end we don't know What Triggers Cosmology's most important explosion ?
I think its supernova but I'm not sure and it could have many of supernova with different explosion...
space science
It is very interesting subject, space science. Recently we had a visiting lecture on Astor biology by Prof. Chandra Wicramasinghe and we were enthusiastic to explore the space.
Beautifull pictures
Hello,
Thank you for this fantastic blog, my favorite at the moment, congratulation.
Bye
Very interesting, I just
Very interesting, I just discovered your blog and the posts are very useful for me. Keep posting. Thanks
Thanks
Hey guys thanks for the valuable information truly liked it keep up the good work. Thanks
panic away
I think it is important
Hi,
I believe it is important to point out which astronomy pictures are actual footage and which are illustrations. It might be very obvious to most people especially from the field of science, but many people might get irritated.
illustrations
We agree and we try to keep all illustrations on our site appropriately labeled. Thank you for letting us know.
Kim Arcand, CXC
Great
Great Information I have found here.Thanks for posting it.
really i agree with you.
I really agree with you. That is awesome.