L.A.Stars wrote:Uh, absolutely one of the most bizarre images I have yet seen on APOD and it comes with no explanation, only a poem. I'm not a scientest, just an enthusiast. What the heck is this picture? Why does Tycho look like that? What is the blue ring? How big is it? Are those dust clouds? Cmon man, don't just put a poem and no explanation! Ugh!
I googled the image and found one which is similar, although the image I found is a combination of X-ray and infrared observations.
Here is the caption that went with that image:
This composite image of the Tycho supernova remnant combines infrared and X-ray observations obtained with NASA's Spitzer and Chandra space observatories, respectively, and the Calar Alto observatory, Spain. It shows the scene more than four centuries after the brilliant star explosion witnessed by Tycho Brahe and other astronomers of that era.
The explosion has left a blazing hot cloud of expanding debris (green and yellow). The location of the blast's outer shock wave can be seen as a blue sphere of ultra-energetic electrons. Newly synthesized dust in the ejected material and heated pre-existing dust from the area around the supernova radiate at infrared wavelengths of 24 microns (red). Foreground and background stars in the image are white.
Image credit: MPIA/NASA/Calar Alto Observatory
As for how big the supernova remnant is, that depends on how far away it is. This is what Wikipedia (
http://en.wikipedia.org/wiki/SN_1572) says about the probable distance to the remnant of Tycho's supernova:
The distance to the supernova remnant has been estimated to between 2 and 5 kpc (approx. 6,500 and 16,300 light-years), but recent studies suggest a value closer to 2.5 and 3 kpc (approx. 8,000 and 9,800 light-years).
So in order to find out how big this cloud is, you have to measure its angular size in the sky and figure out how big it is if it is 8.000 light-years away, and how big it is if it is 9.800 light-years away. The farther away it is, the bigger its actual size will be.
Ann