I think "tornado-like" would be more accurate. Neptune doesn't have an atmosphere as we think of it on earth.
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I think "tornado-like" would be more accurate. Neptune doesn't have an atmosphere as we think of it on earth.
Most planets have an atmosphere, commonly dominated by ammonia or methane. No other planet discovered so far has oxygen and hydrogen (H20) other than earth.
Why are ammonia or methane so common?
I have no idea.
I suspect it is because we have studied so few worlds in enough detail. We know about 9 worlds in our solar system. Perhaps in time we will have more world's to study and be able to see patterns better.
Perhaps the existence of life on Earth helps change the atmosphere.
Or indeed, vice versa...
Re: Atmospheres - Temperature and pressure appear to be the main determinate on how hydrogen (being the most abundant element along with helium in the universe) and other elements combine/sublime/condense on colder planets.
Sol System Planet atmospheres: http://www.universetoday.com/35796/a...f-the-planets/
http://lasp.colorado.edu/education/o...atandwhere.php
Ta ! (short for tarradiddle),Quote:
ATMOSPHERES... The atmospheres of Jupiter and Saturn are made almost entirely of hydrogen and helium, although there is some evidence they contain hydrogen compounds. Uranus and Neptune are made primarily of hydrogen compounds, with smaller traces of hydrogen, helium, metal and rock. The most common hydrogen compounds are methane (CH4), ammonia (NH3), and water (H2O).
The farther away a planet is from the Sun, the cooler its atmosphere will be. This means that the same gases will condense to form clouds at different altitudes on different planets because the condensation of a gas requires a specific amount of pressure and temperature. Ammonia, ammonium hydrosulfide and water make up the 3 cloud layers of Jupiter and Saturn. You can see from the graph to the right that these condense at lower altitudes in Saturn's atmosphere than they do in Jupiter's atmosphere.
tailor STATELY
The Universe Today articles in your link, tailor, are interesting but don't tell us more than the Popular Astronomy article in an earlier post in this thread.
Its been 30 years since the Voyager 2 flyby, so these planets need to be revisited. The 2 ice giants Uranus and Neptune remain the planets we know little about. They are very different. Neptune radiates more heat out into space than it receives from the sun, while Uranus is more sealed in under its icy mantle. The many moons of these two ice giants also remain largely unexplored.
The Voyager 2 Flyby was not enough to even identify and describe many of these moons. Uranus has 27 "known" moons, while Neptune has 14, one of which, Triton, is probably a captured dwarf planet, accounting for 99% of all the mass in orbit around Neptune. See post #524.
Three alien planets around a tiny cold star might be a good place to search for life. Doesn't mean intelligent life or even advanced forms of non-intelligent life.
Also, it seems we are still getting info from Cassini on Saturn's moon Titan. This despite the claims in Popular Astronomy that we are not getting any new material to add to what we knew from the Voyager 2 probe 30 years ago.
I've got my Mac back and can now create links again! Windows 10 was useless, while I used it the links disappeared!
For some reason those exoplanets around tiny stars are easier to study given our current technology. At least that is what I got from the article, but I would have thought larger systems would be easier to spot. Perhaps these smaller ones must be compact for the exoplanets to be in their sun's habitable zone and that compactness is easier for us to spot.
I will expect a retraction in the next issue of Popular Astronomy of the claim that we get no new material since Voyager 2. Cassini is still sending back data from Saturn's moon, Titan, and the lakes of pure methane on that moon.
Knowing that the lakes are pure methane does seem to be new information. The missions to Ceres and Pluto offered plenty of new information. I still wonder what those bright spots are on Ceres.
The bright spots on Ceres is a quite separate issue. The close-up views of Ceres suggest they may be salt deposits. This 2016 discussion of the Ceres project (to be extended to 2017) is the latest I have found: https://spaceflightnow.com/2016/04/0...time-at-ceres/