Astronomers Solve Ancient Supernova Cold Case Using Hot Infrared
Nick Gilbert
at 05:00 PM 25 Oct 2020
Comments 0
A compositeof the various images taken of RCW 86
IMAGE BY NASA/JPL-Caltech/UCLA
Astronomy // 

There's a tonne of unexplained mysteries out there, and stellar phenomena that we can't explain using current scientific models, but a team of American astronomers have at least scratched one off the list - how a 2,000 year old supernova came to be quite as large as it is.

It all started when ancient Chinese astronmers spotted what is now known as supernova remnant RCW 86 spectacularly ending its existantce as star, an event that could be observed from earth for 8 whole months.

While we've known that this was a supernova since the 1960s, the problem has always been how it got to this size. Based on our understanding of physics and working from models built around similar events, the size of the exploding ball of particles and dead star shouldn't be nearly as big as it is. According to PhysOrg.com, the star would be larger than the visible full moon in our sky, if observed using infrared light.

But it's exactly that wavelength of electromagnetic radiation that has solved this particular problem. As it turns out, the supernova was created from a white dwarf. These stars are usually not supermassive enough to actually result in an explosion; instead, they typically continue to shrink. however, it seems that this star may in fact have leeched matter from a nearby star.

According to Brian J Williams from the North Carolina State University, ""A white dwarf is like a smoking cinder from a burnt-out fire. If you pour gasoline on it, it will explode."

And so RCW 86 did. Because of the fact that it exploded from a shrunken star, however, it seems that RCW 86 actually created a 'cavity' of empty space around it.

When the star exploded, it was relatively unimpeded by random floating bits of matter, allowign the debris to accelerate outwards at faster-than-normal rates.

These findings were discovered by taking infrared temperature measurements using NASA's Chandra X-ray Observatory and the ESA's XMM-Newton Observatory. By calculating the temperature of the RCW 86 remnant based on these measurements (200 degree Celsius), they were able to calculate the amount of gas present, which led them to the conclusion that there was a lower-than-expected amount of gas and matter present around the star at the time of explosion.

So, one mystery down. About another eleventy-billion left to go...

[PhysOrg]

 
0 COMMENTS

Leave a comment

Please provide your details to leave a comment.

The fields marked with (*) are required.


Display Name: *
Email *:
Comments *:
(Max 1000 characters)
*

(letters are not case-sensitive)

Enter the text in the image above