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25

Believe it or not, Jupiter isn't too consistent. Take a look at these pictures, the first taken in 2009 and the second taken in 2010: and Quite the difference, eh? Why? Jupiter's atmosphere is made of zones and belts. Zones are colder and are composed of rising gases; they are dark-colored. Belts are warmer and are composed of falling gases; they ...


15

It's red, because it's a 'sunburn'. The clouds in the red spot reach to higher altitudes than the surrounding and are more exposed to Solar UV radiation, which in turn changes the structure of some of the organic molecules etc. This is at least the explanation suggested by recent data from NASA's Cassini mission, see this 5 day old press release.


14

Bigger is better. Most moons, especially those of gas giants, are not "formed", they are just "captured" (unlike our Moon, which could have been captured, but probably was formed in a much more exciting way). Jupiter is the most massive planet in the solar system. It stands to reason that it has a larger region of gravitational influence (where its ...


14

Mass. The more massive a body, the larger the gap between its lowest and highest orbit; the range of speeds at which a random body entering its gravity is likely to remain as its satellite. Sun has millions of satellites if you count all the asteroids; smaller planets tend to have one or two moons at most (Pluto with five being a notable and not fully ...


14

we see that its features didn't change largely over many years Jupiter is huge. It is 11 earths across, and 1300 times our volume. The clouds/bands we can see are vastly larger than Earth's entire ecosystem and that means they have a lot more inertia. Also consider our observation timespan. We have been watching Jupiter* for under 2 centuries, ...


13

The mass of the asteroid main belt is estimated at 4% the mass of our moon according to Wikipedia so any object formed from the aggregation of that mass would not be a planet. It would be the size of a very small moon. Even if all the asteroids in the solar system were combined, the total mass would be below a third of the moon's mass.


11

http://spaceplace.nasa.gov/review/dr-marc-solar-system/gas-giants.html We think of a gas as something very . . . well, airy. After all, air is the gas we all know and love. We breathe it and fly planes right through it with no trouble. So it makes sense to think that a gas planet must be like a big, airy cloud floating out in space. Saturn in true color. ...


10

Rings are made up of tiny (and not so tiny) pieces of rock and ice that are in some way the bits "left over" from the formation of the planet. One theory is that they are formed when a moon comes closer to a planet than the Roche limit the tidal forces cause it to break up and form a ring. Though the presence of "shepherd" moons in the rings of Saturn does ...


10

Comet Shoemaker–Levy 9 crashed into Jupiter a few years back. As well as these molecules, emission from heavy atoms such as iron, magnesium and silicon was detected, with abundances consistent with what would be found in a cometary nucleus. Those heavy elements are consistent with the comet being at least being partially composed of rock. So Jupiter ...


9

Many models shown in books or television show a very populated asteroid belt but in fact the belt is mostly empty. To answer your question, the inclination of the asteroids vary a lot going from 0° to 40° although most off them are in between 0° and 30°; See The orbital element distributions of real and modelled asteroids. So yes it would be 3 dimensional. ...


9

@Arne is right in his answer about two things, that the most suitable frequency for Jovian amateur radio is 20.1 MHz, and that this is a 15 meter wavelength. However, the antenna can actually be half the wavelength, and amateur radio astronomers have had good results listening to all kinds of Jovian sounds, including detecting occultations of its many moons ...


8

No. The asteroid Belt is on average about 2.6 AU from the Sun. Earth is 1 AU from Sun, 1.6 AU from the asteroid belt. Jupiter is 5.2 from Sun, 2.6 AU from the asteroid belt. I.e. much further away. Also, it should be easier to see asteroids from inside their orbit since they reflect more sunlight towards us. From Jupiter you would see their shadowed ...


7

That's no good idea. Earth wouldn't necessarily fall into Jupiter in the short run, provided it orbits Jupiter fast enough (within about 1.7 days), and on a circular orbit, but we would risk to collide with Io, destroy it by tidal forces, or change its orbit heavily. The other Galilean moons would get out of sync and change their orbits over time. Tides ...


7

I concur with everyone else here (of course) that the gravity at the "surface" of Jupiter is entirely determined by the mass contained within that surface. The composition makes no difference. However I differ with some on the answer to the headline title question. We simply do not know whether Jupiter has a rocky core. A popular theory for the formation ...


6

The largest main belt asteroid is 1 Ceres, which alone contains almost a third of the total mass of the whole main asteroid belt. Ceres is large enough to be in hydrostatic equilibrium, i.e. its own gravity is strong enough to pull it into a roughly spherical shape. Since the mass of a spherical planet scales as the cube of the diameter (assuming constant ...


6

I'm not sure I understand your question entirely, but i'll do my best to offer a decent answer. It's true that the composition of Jupiter is very similar to that of the Sun (very similar approx. $H$ and $He$ abundance and pretty similar in density). The problem is that Jupiter is not nearly massive enough to have the internal pressure and temperature to ...


6

It doesn't matter if the body is made of gas, rocks, liquid or plasma, the four states of matter all have mass. So, as we know, mass create a gravitational field, and the more mass the stronger the gravity - and Jupiter has 317x Earth mass.


5

The Sun burns hidrogen, so it is a star. Jupiter does not, so it is not a star. Not even a brown dwarf. Since a non-star body orbits a star, it is a planet, a dwarf planet or an asteroid/comet. Since Jupiter has cleared his orbit, it is a planet. Why do I say that Jupiter orbits a star? This is where I go to the center of your question. The orbit of the ...


5

Yes, stacking Barlow lenses is a common practice to effectively increase focal length by multiplying their individual focal lengths. When I say common, most advanced eyepieces actually have many glass elements and are a type of a Barlow lens themselves, so just by using a single Barlow lens in front of your eyepiece you'd already be, technically, stacking ...


5

According to Newton's Law of Universal Gravitation, you simply need interacting masses in order to generate a gravitational force between them. Gases have mass and they therefore can contribute to gravity. So even if Jupiter is entirely gaseous, it is so incredibly massive besides (so much gas!), that it has a much stronger gravitational pull than Earth. ...


5

Nothing "escapes" a BH - in the sense that a signal originating inside the event horizon remains forever inside. If something is observed moving away from the BH, then it was generated outside the event horizon. If it was generated inside, it would never be observed at all, forever and ever. Gravity itself does not "escape" a BH - and neither does "not ...


5

You only need two formulae. Gravitational field of a spherically symmetric mass distribution is given by $$g = \frac{GM}{R^2},$$ where $M$ is the mass inside a radius $R$. The second formula is the average density of a sphere is its mass divided by its volume, hence $$\rho = \frac{M}{(4/3)\pi R^3}$$ These two formulae can obviously be put together to give ...


5

There are at least two interpretations to this problem: Per Wikipedia, Jupiter's surface gravity is $2.528$ times Earth's. Thus, if the Earth were $2.528$ times denser, it would have the same surface gravity as Jupiter. The Earth's current density is $5.514$ grams per cubic centimeter, so the new density would be $2.528 \times 5.514$, or about $13.9394$ ...


4

No, it is not since Jupiter is not a star. We call the system of a star with its planets surrounding the center of mass a simply "solar System".


4

The StarGazers lounge featured a radio kit article for Jupiter radio astronomy. The same article is also featured over at the Radio Group of BritAstro. It seems that 20.1 MHz is the suitable frequency for amateurs observing Jupiter. I am far from being an expert for radio astronomy, but for a small source such as Jupiter, I would assume that you need a big ...


4

Shoemaker Levy 9 was estimated to have released kinetic energy equivalent to 300 gigatons of TNT. That is 1.255×10^21 J. This release through friction and compression was sufficient to heat the atmosphere to 4000K at first. That in turn should probably be enough to break down the molecular hydrogen and methane, releasing further energy. But that's only my ...


4

Sun-Earth distance: 1AU Earth-Jupiter distance (at the conjunction): 4AU So Lucifer will be four times farther than Sun when it is nearer (six times when it is farthest), and at the same time it is a thousand times smaller. This is approx 40 times more light than full moon concentrated in a tiny point on sky.


4

Jupiter is highly dynamic: Jupiter Animated Video Gallery (be sure to look at storm merger video) Differences Spotted in Jupiter's Big Red Storms Jupiter's New Red Spot Jupiter Loses Big Belt; Great Spot Left Hanging The persistence of Jupiter's Red spot is in fact a bit of a mystery.


4

I won't argue with the wikipedia definition (although the NASA Jupiter fact sheet lists it as the radius at 1 bar), but just to point out that the scale height of the atmosphere of Jupiter is given by, $h \sim kT/m g$, where $T$ is the temperature, $m$ is the mean molecular mass and $g$ is local gravity. Putting in some numbers: $ g \simeq 24.8 m/s^2$, $m ...



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