Why isn't venus' dense atmosphere blown away by solar wind, even though it has no magnetic field?

Question

Mars' atmosphere was blown away and it's farther away from the sun then venus.

mars doesn't have a magnetic field and it's atmosphere was blown away, plus its' farther away from the sun. If the earth didn't have a magnetic field, which it does, its atmosphere would be blown away too.

Answer 1

Slow rotation & gravity - oy - the pressure at the surface is 90 atmospheres or about the pressure at one km below the surface of any of our oceans.

Answer 2

A magnetic field is not what maintains an atmosphere.
Venus has a weaker gravity than earth but it's atmosphere is much denser and heavier than earth's,solar winds nor anything else could blow it away.
If it's environment changed radically through chemical or other means I guess it could eventually become thin enough to lose it
I don't think that will happen for a while.

Answer 3

No specific explanation is available, however, the following extracts may shed light at your question and you may be able to figure it out by yourself why venus' dense atmosphere is not blown away by solar wind.

Extracts:
-Venus has no magnetic field, perhaps because of its slow rotation.

-There are strong (350 kph) winds at the cloud tops but winds at the surface are very slow, no more than a few kilometers per hour.

-There are no small craters on Venus because small meteors burn up in Venus's dense atmosphere before reaching the surface. Craters on Venus seem to come in bunches indicating that large meteors that do reach the surface usually break up in the atmosphere.

-Recent results from the Magellan gravity data indicate that Venus's lithosphere (crust and upper mantle) is stronger and thicker than had previously been assumed. Unlike Earth, convection in the defrming lower mantle produces stress on the surface which is relieved in many relatively small regions eposodically instead more continually at plate boundaries as is the case on Earth.

Answer 4

you have some genuine inaccuracies on your question, in the beginning. all the planets shaped around the comparable time, approximately 4.6 billion years in the past, and it is not any longer authentic that the different inner planets are geologically inactive. you're splendid that Mars has a vulnerable magnetic container and skinny environment, Mercury is purely too close to to the solar to harbor any existence, yet Venus is fairly geologically energetic. There are volcanoes that spew acid and CO2 into its environment on a daily basis. that's achieveable that existence would have existed on Venus or Mars faster or later in the previous, and might even exist there now. Venus and Earth probable had comparable situations early of their history, yet went down very distinctive paths by way of particular events. some scientists even think of the top layers of Venus' environment are appropriate for helping existence splendid now. splendid now we are specializing in answering this question for Mars, to work out if situations have been appropriate in the previous or if microbial existence even exists there now. I doubt complicated, sensible existence ever had of undertaking on Venus, and it is not any longer very probable on Mars, the two. If a civilization ever arose on Mars and that they went extinct or fled, we would think of they might go away some information in the back of, yet none has ever been got here upon. What we do understand is that Mars had an abundance of water in the previous, and that some gasoline sizeable moons may even at the instant harbor existence, which incorporate Europa and Titan.

Answer 5

Mars lost it's atmosphere due to interplanetary war not solar wind. The enemy bombed mars so severely that they destroyed much of the Martian crust. The heat and resulting forces blew the atmosphere off into space. In its last dieing gasp Mars managed to destroy it's enemy and thus created the asteroid belt out of their enemy's home planet. Then those still alive flew the Moon to Earth to start a new life. Us!

Answer 6

it's all about the gravity!!!!! vensus has a strong enough gravity to hold its atmosphere whereas mars is much smaller and therefore has a weaker gravity. secondly, the earths magnetic field isnt responsible for keeping our atmosphere intact, it just prtects us from harmful solar radiation. hope this helps!!!!!

Answer 7

The reason is because Venus, at 3,760 miles around, is a much larger planet than Mars, at 2,110 miles so it has a higher gravity which holds on to its atmosphere.

Answer 8

It looks like the atmosphere can simulate a magnetic field:

http://www-spc.igpp.ucla.edu/personnel/russell/papers/venus_mag/

http://sunearth.gsfc.nasa.gov/sunearthday/2004/vt_venus_planetary_2004.htm

EDIT: Ignore my 1st answer, I changed it.

Answer 9

Mostly it's held in place by Venus's gravity.

Doug