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12

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.


12

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 ...


12

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 ...


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

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 ...


8

@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 ...


6

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 ...


5

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 ...


5

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 ...


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 ...


4

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 ...


4

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 ...


3

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.


3

Go with the Option 1 (135mm) as it has bigger light collecting area i.e. diameter of primary mirror. It will enable you to faint objects and it will also help you to see the dim object under greater zoom eyepiece e.g. 4mm or 10mm.. Also dont let you fool yourself with the bigger numbers advertized by telescope vendors like 238X zoom or 300X zoom... First ...


3

No, it is not just a matter of migration. You need to take into account two facts. One is that (as experience shows) Io's own gravity is enough to avoid it breaking by tidal forces. It has been like that through all its history: Io could not have been formed if it started aggregating today, but it was formed at the same time Europa and Ganymede did: they ...


3

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 ...


3

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 ...


2

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".


2

Derived from this paper the interval between March equinoxes for 1989/1990 has been 4 minutes 28 seconds longer than the corresponding interval for 1987/1988. So the length of a year can vary several minutes, e.g. by gravitational effects of other planets. For calendars a mean year is used. Atomic clocks run far more precise than the more or less periodic ...


2

Sometime after 4.5 billion years, the sun will change into a red giant star and expand to about 1 AU. Some people think it will be beyond Earth's orbit. (In any case, Earth's orbit would have changed and likely to have struck the surface of the expanded sun.) The asteroids would experience a stronger solar wind and their orbits would become more elliptical, ...


2

The simple answer is yes, because magnetic fields extend to infinity. Your question should ask if a significant interaction is present. My question would be, what is a significant interaction?


2

In reality, Jupiter doesn't have nearly enough mass to initiate stellar ignition or sustain it if we could somehow start it going. Even the smallest star would require on the order of some 80 to 90 times the mass of Jupiter just to put out a faint red glow. Even to become a brown dwarf proto-star, Jupiter would require a mass increase on the order of at ...


2

Ignoring the impossibility of Jupiter going solar: Assume that Jupiter turns into duplicate of the Sun in terms of energy output. Energy transmitted to the earth follows an inverse-square law. Since Jupiter is, at best, 4 times farther from the Earth than the Sun, Jupiter will supply the Earth with, at most, 1/16 the energy that the Sun supplies, for an ...


2

Is it possible to view Saturn in little yellowish and Mars in little reddish using following telescopes? It is definitely possible to observe the rings of Saturn with telescopes this size. Even the Cassini division should sometimes appear visible, if the instruments are well collimated and seeing is not too bad. In terms of color, Saturn is just a ...


1

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 ...


1

The total mass of the asteroid belt is just about 4% of the mass of our Moon. Even if the asteroids don't collide with other planets in the meanwhile, the mass is too low to form a planet in the sense of the 2006 IAU definition. Even if Ceres would accrete all asteroids in the asteroid belt, its radius wouldn't grow to the double of its present radius, ...


1

It's pretty simple, really. The shadow of Jupiter, just like the shadow of the Earth, is not razor-sharp. There is an intermediate region, called penumbra, where illumination is partial. This is due mostly to the fact that the Sun is not a mere dot, but has a measurable size. The fact that the planet itself does not have a sharp edge also contributes a small ...



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