Dawn enters Vesta orbit

[dre]

Mentioned that in the 2nd paragraph you quoted

Ok, I see it now But its not just "solar wind" right? Even in deep space theres hydrogen atoms and drag... just not much.

[Bonam]

Ok, I see it now But its not just "solar wind" right? Even in deep space theres hydrogen atoms and drag... just not much.

Yep, that's true. In the solar system, where the planets are, the interplanetary medium is dominated by the solar wind. That's true all the way out to the heliopause, after which the interstellar medium of gas and dust through which the helisphere moves is dominant. That medium pervades the galaxy. Outside the galaxy, there is the intergalactic medium, which is of course even less dense.

[DogOnPorch]

That's true all the way out to the heliopause, after which the interstellar medium of gas and dust through which the helisphere moves is dominant. That medium pervades the galaxy.

A great example of this is Kronberger 61.

http://blogs.discovermagazine.com/badastronomy/2011/07/25/a-glowing-bubbly-bauble-in-space/#more-35005

Nice close-up of Vesta released...

http://www.space.com/12420-asteroid-vesta-nasa-photo-dawn-spacecraft.html

[Oleg Bach]

Thanks guys I do enjoy explaining scientific concepts when people are interested.

Love the natural world and beyond. People should understand that science is not some cold thing that is about numbers- It is nature explained - If you enjoy nature - you should love science. We are living in the midst of science. Young people who have no interest in the subject should change their attitude..science can be as friendly and comforting as that beaufiful shade tree.

[Wild Bill]

Ok, I see it now But its not just "solar wind" right? Even in deep space theres hydrogen atoms and drag... just not much.

Not much? How about one or two atoms per square metre?

If that's not "mice nuts" I don't know what is! You'd be measuring the effects of drag over billions of years!