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27

But why can't Jupiter be a Y Dwarf who is in the binary relationship with the Sun? There are two reasons: One is that Jupiter is too small to have ever undergone fusion of any sort. To qualify as a brown dwarf, an object needs to be large enough to have undergone deuterium fusion in its core. This requires a mass of at least 13 Jupiter masses. The other is ...


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 ...


19

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 ...


18

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. The theory involves the Roche limit - and is that particles that are already within this limit can't accrete into a larger body because of the tidal forces involved. Another theory is that they are formed when a moon ...


17

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.


15

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.


15

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

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, watching ...


12

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. ...


11

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.


11

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 ...


11

...a very blurry, small view of Jupiter with the 4mm and Barlow... Be aware that a 4mm eyepiece and a 3x barlow at the same time will give you a very high magnification - too high! For regular Jupiter viewing I would suggest you stick to 100x or 200x at most, unless the air is exceptionally still. (After a few sessions you'll find out what "Still" air ...


10

@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 ...


10

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 ...


9

Before I start, I'll admit that I've criticized the question based on its improbability; however, I've been persuaded otherwise. I'm going to try to do the calculations based on completely different formulas than I think have been used; I hope you'll stay with me as I work it out. Let's imagine that Lucifer becomes a main-sequence star - in fact, let's call ...


9

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 sides....


9

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 ...


9

How can a planet capture a moon? There are 178 moons in the Solar System, according to the NASA Planetary Fact Sheet, so it seems to be a common event. The following sections will show that moon capture is actually unlikely, but when a planet has one or more moons capture becomes easier. Initial Conditions Starting from the initial conditions, the planet ...


8

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 ...


8

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.


8

Jupiter does not have a "surface" and nor is there anything but an arbitrary division between interplanetary space and where its atmosphere begins. The crushing pressure is its atmospheric pressure. The deeper into the atmosphere you go, the greater the column of gas that lies above you. It is the weight of this column of gas that is responsible for the ...


8

I'll give this one a shot. Correction is welcome. Upper atmosphere temperature. It's not just elements that give a planet color, but the temperature of elements. When we examine what a planet looks like, we're basically talking about reflected sunlight from the planet's surface or atmosphere. With Earth, its atmosphere is transparent enough that its ...


7

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 ...


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 ...


7

No, the galactic magnetic field is very weak, about 0.1nT. It is able to bend the trajectory of highly-energetic charged particles and also to align dust grains across the magnetic field. However, is too weak to affect the rotation of a galaxy. Although the origin of galactic magnetic field is not clear yet, the supermassive black holes do not ...


6

Shoemaker Levy 9 was estimated to have released kinetic energy equivalent to 300 gigatons of TNT. That is 1.255×1021 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 ...


6

Use an orrery that will let you specify a specific epoch and vantage point. There are some quite fancy ones online, for example this Solar System Scope: What you do in this particular tool is click on the calendar bar below and enter date and time of your observation (if you forgot that, there's a good chance your photograph has a time stamp, either of ...


5

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 ...


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 ...



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