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7/25/2013

SN 2013DY in NGC 7250

Okay, I lied. My next post is this morning, almost, and it is on the new Type Ia Supernova in the galaxy NGC 7250.  If you know a lot about Supernova, you may want to pass on this entry. If you want to look at the blown up images to see identify the area the white dwarf(s) that went supernova originated from, look at the images. Be warn, I do have a humanitarian message at the end. Bottom line, you can view this SN right now and if you have a telescope of 8 inches or more, maybe 6 inches and a good dark site, go for it and view this bright new Supernova. It should be reaching peak soon and then will begin to fade.  You can look at images by wonderful amateurs who have imaged the galaxy and SN 2013DY at this link at Bright Supernova.

The color images are coming from Professor Courtney Seligman's site at this link.  From that site we learn that NGC 7250 is a starburst galaxy which I guessed when I saw it, and that it is about 55 million light years from us.  Just think, if that is true when this white dwarf actually blew itself up the Earth was entering the Paleocene–Eocene Thermal Maximum where the Earth in a heated up over 11 degrees F or 6 degrees C and caused the extinction of around 45 to 50% of all species on Earth, including a lot of ocean animals. Mammals did fine through this though.  Look it up for more information, it is rather interesting.  Anyway, we also know that this site that the galaxy is about 25 thousand light years across. The professor also states from the site,

"In the closeup below, NGC 7250 is the galaxy at the center. The group of three bright blue knots above center is listed as a quarter arcmin wide galaxy (PGC 214816) in LEDA, but I can't find any other reference to such a galaxy, and the knots look more like a part of NGC 7250 than anything else."

Head on over in the link if you want to learn about NGC 7250.  I would agree to me, the knots look to be part of NGC 7250 and possibly part of new star formation areas, but I'm not a pro so I am probably totally wrong on that. Right now SN 2013DY is about mag. 12.6 to 13.0 (I vote for the mag. 12.6 or so) and that puts in the range of amateur telescopes. NGC 7250 is found in the constellation of Lacerta which is visible at this time.

Below I have two sets of images of the NGC 7250, the black and white I used JING to capture an image from Stan Howerton's excellent image over at Bright Supernova.  I did this so you can compare the before and current images. In truth, and it is far beyond the possibilities of any survey I have access to but I was seeing if it was possible to see the general area where the progenitor originated in any images. Yep, it is. Can I see the actual binary pair? Nope, and I knew that. The best I can do is to capture the general area.  Just something fun I want to do with brighter supernova is I think to try and go after and see if I can find the progenitor star or white dwarf's general area.  Maybe one day I'll get lucky and we'll have another Supernova in M31 (been over a 100 years now) and I can try to identify the progenitor there. Probably will never happen but I can at least get the general area.  Anyway you can see in the top color image the two stars or clumps above the brighter and bigger ones across and slightly up from the writing and arrow.  Things are far too tine to see where a progenitor may be. However, in Mr. Howerton's image you can clearly see how bright SN 2013DY is and that it is located slightly down from the two white stars that look like doubles, and slightly across and up from the two blue stars that are positioned going from the left corner to the right corner. So location is identifiable.






Here I really blew up some images to show those two diagonal stars going from bottom left to upper right . If I go to the bottom blue one, that make up the three by themselves, and slightly across to the left and slightly up, I see nothing. Do I think the progenitor white dwarf is there? Yep, somewhere. Since this is a Type Ia SN, that means a white dwarf (and we won't see it from this distance with amateur telescopes, anyway, the white dwarf stole enough mass from its binary companion as the companion began its final journey and become a Red Giant, and the white dwarf's mass eventually went over the Chandrasekhar limit of 1.40 (I've seen it as 1.38, 1.40 and 1.44 so I am going with the 1.40 which is in the middle) and blew itself up in a runaway thermonuclear reaction.  The other way is that two stars each over their lives spent time on the main sequence, were less than 6 solar masses or so and became Red Giants and then both eventually settled as white dwarfs. I would assume and that is dangerous that as one was a white dwarf and the other going through the Red Gian phase, that as mass was accumulated, it eventually was blown off from the white dwarf in what astronomers call a nova. Thus the white dwarf never accumulated enough mass to go over the Chandrasekhar limit and never became a Type Ia Supernova. Eventually the companion did become a white dwarf also, and that meant we had two white dwarfs orbiting each other. Well, their mass attracted themselves to each other, and much like a couple in love who should never hook up but do, when the two white dwarfs embrace in their deathly dance and kiss, becoming one, the Chandrasekhar limit is surpassed, and BOOM, a Type Ia Supernova occurs. 

So in SN 2013df we have a Type Ia Supernova (the spectra that astronomers take tells them what tpe of Supernova they have.  You can make your own at Cool Cosmos at this link, and you can see what a spectrum is. The colors tell you what elements are present. If you make one,  NEVER USE IT TO LOOK AT THE SUN!!!!!!!!!). Anyway if you compare the two pictures you can get a general feeling where the progenitor came from, its location and then you should see something else. You should see HOW MASSIVE these Supernova area!!!!!  They are shinning brighter than the galaxy in the sky.  If you turn your telescope to it, you'll see it if you have a big enough scope and you'll see the fainter galaxy.  I'll do this I hope next week one night.  But look at how bright and big SN 2013dy is! Incredible. 




So what is the purpose of all this? To see something, know its general area where the progenitor came from, understand part of the process, and realize how powerful these things are. Equally important, these supernova seed the surrounding area in space with heavy metals that are used to make new stars/suns, new solar system and I would hope, somewhere, new life. The iron in our blood, the calcium in our bones and the heavy elements we use in our daily lives all came from a Supernova and these elements, created the Sun which is our star, the solar system our pale blue dot is located in, and that very pale blue dot we all live on.  These elements were used to create life on this planet.  So, next time you hear about a Supernova, remember in its final act of dying, in its death, the star, gives back and creates.  In a way, the star is giving of itself back to the universe so new things can come from it. May we be like a supernova and look to give back to others by being kind, caring and helpful to each other.