Now for something completely different ...

For those of you who didn't know, I'm an astronomer, and my research field is this - protoplanetary disks. These are the rotating disks of gas and dust that surrounds new-born stars. Inside these disks planets form. We see these disks around stars that are born today - and it is how it looked when our Sun was born 4.5 billion years ago.

A protoplanetary disk is a chaotic place - we were born in chaos, and the final layot of our solar system and planets is a direct result of how the disk behaved and developed over the 5-10 million years it existed before our growing sun became so bright as to evaporate it.

We cannot actually take as high-resolution a picture of a disk as seen here - even our strongest telescopes are not capable of this. I create computer models of such disks and compare them with what we can actually observe of the real thing - this way we can learn more about how they work internally.

For posters and scientific presentations I have always used various artistic impressions of disks grabbed around the web. Figured I should be able to make one of my own so I don't have to worry about breaching some poor artist's copyright.

The gas surface is clumpy and gas becomes energized where the star's light happen to hit the raised parts. With some good will one might make out some yelowish dots in gasseous gaps, precursors to giant planets.

Note that the perspective is a bit skewed - we are seeing the sloping edges of the disk, but in reality those edges would of course extend also on this side, obscuring our view. So instead I show the cross-section of the disk and cut away the obscuring foreground. These disks are only warm close to the center (the innermost 10AU or so), out towards the edges (disks can be 50-1000 AU depending on where their stars are born) or deep inside where the newborn star's light cannot reach, they are very cold - very close to the absolute zero.

MyPaint + GIMP.
.
Griatch

pretty impressive stuff there

You have there really great art!!! thank you

Beautiful work, Griatch!

Along with the explanation, your image gives me the same kind of feeling that I get when two mirrors are angled and I look down a "hallway" of infinite reflections. Scary and full of wonder at the same time. Thank you for the explanation along with the image.

I had no idea that newborn stars also projects particles at the polar axis like that of the creation of black holes Griatch. Cool stuff. the new solar system looks beautiful too.

Damn that's cool.

fascinating...I love the explanation as well as the art. I never had thought about it before, how clumpy the gaseous clouds would be, your picture really portrays that well.

Thanks for the comments.



I should be able to explain stuff around this, I've held enough lectures about it. It's of course impossible to truly convey the tremendeous scales here, I can only hope to give a hint.



Yes, it was long predicted, but but the jets have these days actually been observed. They are mainly prevalent while the disk is young and the rate of material falling onto the star large. Physically, the jets might be the only way for the star to get rid of the angular momentum given it by the infalling material.



Yes, for a long time we thought the protoplanetary nebula/disk was a quiet and well-ordered place where planets formed rather peacefully. This has turned out not to be the case. We were literally born out of chaos and even after the gas disk itself went away the giant planets played billiards with each other a few times (shovering us with waves upon wave of asteroids in the process) before settling into their current configuration (this is coincidentally called The Nice model of planet formation ("Nice" pronounced "Niss", as in the city, not as in being friendly).
.
Griatch

I love stuff like this. Not only is there magnificent artwork, there is the explanation of totally awesome information.

I am totally addicted to NASA's Astronomy Picture of the Day. Not only do they have great images, there is an explanation.

To go along with your post, Griatch, here is one of APOD's: Protoplanetary Survivors in Orion

I love the picture Griatch and a great explanation.

I have heard of the idea we are originally created out of chaos might explain a whole lot of things really.

Still very interesting stuff to read about and look at.

Liana

My enquiring mind wonders about the "arms" of falling matter (I also wondered for the polar jets, but you answered that).

Your picture renders well the chaos (and dirtiness) of planet creation, and the skewed perspective make it look like a gravitational well.

As you notice the innermost part of the disk looks "empty". This is because close to the star the radiation is so intense that gas evaporates and dust shatters into atoms. If there is gas, it is so highly energized so as to radiate in wavelengths we cannot see with the naked eye. There are several observations that indicate that matter gets bled off from the disk, crosses the gap and slams into the stellar surface only along one or two "arms" of highly ionized gas. The impact points of those "arms" is in fact extremely bright in short wavelengths.
.
Griatch

It must be a coincidence, but another artist is giving astrophysics classes today:

http://www.phdcomics.com/tv/

@ofnuts

That's a pretty nice little presentation of dark matter actually. I used to read PhD comics a long time ago, but it tends to be a bit repetetive after a while. But some stuff, like this, is really good!
.
Griatch